Posted: October 20th, 2022

ONSHORE BALLAST WATER TREATMENT STATIONS: A HARBOUR SPECIFIC VECTOR MANAGEMENT PROPOSITION

ONSHORE BALLAST WATER TREATMENT STATIONS: A HARBOUR
SPECIFIC VECTOR MANAGEMENT PROPOSITION

ABSTRACT
The discharge of Harmful Aquatic Organisms and Pathogens (HAOP) found in ships
ballast water from one port environment to another can have severe ecological,
environmental and economic consequences, especially when they transform into
marine pests. This informs the necessity to investigate treatment options that could
curtail the transfer of these organisms from a source harbour. An alternative to the
conventional Ballast Water Treatment Systems is investigated and proposed in this
study- it entails the onshore treatment of host port water before it is loaded as ballast
water into ships. The study covered sampling of Port Harcourt Harbour water in
Nigeria. The field samples were subjected to laboratory analysis. Inferential statistics
was employed to determine the relationships between the physicochemical properties
of sampling stations and organisms’ density.
Literature on ballast water treatment research were reviewed, and the most viable
treatment options for Port Harcourt Harbour based on the field results obtained were
discovered to be treatment combinations that could remove most of the species found
in the study area, especially; Alexandrium minutum, Acartia clausi, Pseudocalanus
elongatus, Tortanus sp., and Oncaea sp., which are non-indigenous to North
America; one of the Harbour’s leading trading regions in the world.
A three stage shore treatment combination process was therefore, proposed by the
study for employment in the Harbour. The first stage involves filtration of the
harbour’s sea water to remove the larger organisms, mainly zooplankton. It is
followed by a stage of heating of the harbour’s water (>38oC) to remove larger
zooplanktons that have escaped the filtration process. The third stage shall involve
the use of biocides-this entails the application of chemicals like ozone (which has a
strong lethal effect on a lot of phytoplankton and bacteria). And finally, the treated
sea water is pumped into the visiting ship as treated ballast water.
Key words: Ballast Water Treatment, Harmful Aquatic Organisms and Pathogens
(HAOP), Planktons, Ballast Water Exchange (BWE), Ballast Water Performance
Standard, Propagule Pressure (PP).
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TABLE OF CONTENTS
Table of Contents
DECLARATION…………………………………………………………………………………………… ii
ACKNOWLEDGEMENT……………………………………………………………………………… iii
ABSTRACT………………………………………………………………………………………………… iv
TABLE OF CONTENTS………………………………………………………………………………… v
LIST OF TABLES………………………………………………………………………………………… ix
LIST OF FIGURES ………………………………………………………………………………………. ix
LIST OF ACRONYMS ………………………………………………………………………………….. x
CHAPTER ONE……………………………………………………………………………………………. 1
INTRODUCTION …………………………………………………………………………………………. 1
1.1 STUDY AIM AND OBJECTIVE……………………………………………………………. 1
1.2 THE LIMITATION OF THE STUDY …………………………………………………….. 2
1.3 BACKGROUND…………………………………………………………………………………… 2
1.3.1 What is Ballast Water? …………………………………………………………………….. 3
1.3.2 Why is Ballast Water a Problem?………………………………………………………. 4
1.3.3 Invasion Pathway…………………………………………………………………………….. 6
1.3.4 Ballast Water Hazard……………………………………………………………………….. 9
1.3.5 Risk Assessment of HAOP Invasion………………………………………………….. 9
1.3.6 International Efforts……………………………………………………………………….. 13
1.4 PROBLEM STATEMENT …………………………………………………………………… 18
1.4.1 Management of Harmful Aquatic Organisms (HAOP) Invasions ………… 20
CHAPTER TWO…………………………………………………………………………………………. 21
REVIEW OF RELATED RESEARCH…………………………………………………………… 22
2.1 LITERATURE REVIEW OF SOME PHYSICOCHEMICAL PARAMETERS
OF BONNY AND CONTIGUOUS RIVERS IN NIGERIA…………………………… 22
2.1.1 Water Temperature………………………………………………………………………… 23
2.1.2 pH levels………………………………………………………………………………………. 24
2.1.3 Electrical Conductivity…………………………………………………………………… 25
2.1.4 Salinity…………………………………………………………………………………………. 26
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2.1.5 Turbidity………………………………………………………………………………………. 26
2.1.6 Total Dissolved Solids……………………………………………………………………. 27
2.1.7 Dissolved Oxygen (DO)…………………………………………………………………. 27
2.2 USE OF SURROGATE ORGANISMS/ PROXY GROUP ………………………. 29
2.3 REVIEW OF TREATMENT METHODS………………………………………………. 30
2.3.1 Filtration and Physical Separation Systems ………………………………………. 30
2.3.2 Biocides……………………………………………………………………………………….. 31
2.3.3 Other Treatment Methods……………………………………………………………….. 36
2.3.4 Combination of Treatment Methods ………………………………………………… 37
CHAPTER THREE ……………………………………………………………………………………… 40
METHODOLOGY AND DATA COLLECTION ……………………………………………. 40
3.1 DESCRIPTION OF THE STUDY AREA………………………………………………. 40
3.2 THE SCOPE OF THE STUDY …………………………………………………………….. 41
3.3 SAMPLING LOCATION…………………………………………………………………….. 41
3.3.1 Sampling Stations………………………………………………………………………….. 42
3.4 SAMPLE ANALYSIS …………………………………………………………………………. 43
3.4.1 Methodology for Physicochemical Characterization of Study Area ……… 43
3.4.2 Methodology for Biological Characterization of Study Area ………………. 46
3.5 DATA ANALYSIS……………………………………………………………………………… 47
3.5.1 Statistical Analysis ………………………………………………………………………… 47
CHAPTER FOUR………………………………………………………………………………………… 49
ANALYTICAL REVIEW OF FIELD DATA………………………………………………….. 49
4.1 PHYSICOCHEMICAL PROPERTIES OF STUDY AREA……………………… 49
4.1.1 Temperature (oC)…………………………………………………………………………… 49
4.1.2 pH level ……………………………………………………………………………………….. 49
4.1.3 Electrical Conductivity (µscm-1
) ……………………………………………………… 49
4.1.4 Turbidity (Natural Turbidity Units (NTU))……………………………………….. 50
4.1.5 Salinity (PSU)……………………………………………………………………………….. 50
4.1.6 Dissolved Oxygen (mg/l) ……………………………………………………………….. 50
4.1.7 Total Dissolved Solids (mg/l)………………………………………………………….. 50
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4.2 BIOLOGICAL CHARACTERISTICS OF STUDY AREA WATER
SAMPLES……………………………………………………………………………………………….. 51
4.2.1 Composition, Distribution and Relative Dominance of Plankton …………. 51
4.2.2 Biological Differences……………………………………………………………………. 52
CHAPTER FIVE …………………………………………………………………………………………. 57
DISCUSSION……………………………………………………………………………………………… 57
5.1 ONSHORE VERSUS SHIPBOARD TREATMENT SYSTEMS………………. 57
5.2 PROPOSED TREATMENT SYSTEM ………………………………………………….. 61
5.3 HARBOUR RISK MANAGEMENT …………………………………………………….. 65
5.4 STATE RESPONSIBILITY …………………………………………………………………. 67
5.5 MANAGEMENT DECISION FLOW CHARTS …………………………………….. 70
CHAPTER 6 ……………………………………………………………………………………………….. 74
CONCLUSION AND RECOMMENDATIONS ……………………………………………… 74
6.1 CONCLUSION…………………………………………………………………………………… 74
6.2 RECOMMENDATION ……………………………………………………………………….. 75
REFERENCES: …………………………………………………………………………………………… 77
APPENDICES …………………………………………………………………………………………….. 87
Appendix A: PHYSICOCHEMICAL PARAMETERS………………………………….. 87
Appendix B: PHYTOPLANKTON TAXONOMIC LIST ……………………………… 88
Appendix C: ZOOPLANKTON TAXONOMIC LIST…………………………………… 89
Appendix D: SUMMARY OF THE ORIGIN, ECOLOGICAL, ECONOMIC,
AND HEALTH IMPACTS OF SOME HARMFUL AQUATIC ORGANISMS
AND PATHOGENS (HAOP):……………………………………………………………………. 90
Appendix E: SUMMARY OF STATISTICAL ANALYSIS RESULTS OF FIELD
DATA USING GRAPHPAD INSTAT® VERSION 3.10 STATISTICAL
SOFTWARE. …………………………………………………………………………………………… 96
Summary of Statistical Analysis of Physiochemical Properties……………………. 96
Summary of Results of Statistical Analysis of Phytoplankton Data ……………… 96
Summary of Results of Statistical Analysis of Zooplankton Data ………………… 98
Appendix F: FULL TEXT OF IMO AND UN CONVENTIONS MENTIONED IN
THE STUDY………………………………………………………………………………………….. 100
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International Maritime Organization (IMO) Conventions …………………………. 100
United Nations (UN) Conventions…………………………………………………………. 106
Appendix G: GLOSSARY……………………………………………………………………….. 108
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LIST OF TABLES
Table 1 Planktons Identified as Non-indigenous to North America Sampled……….69
LIST OF FIGURES
Figure 1.1 Cross Section of Ship’s Ballast Tanks and Ballast Water Cycle …………… 5
Figure 1.2 Prawn and Clam life-cycles showing Planktonic Stages……………………….6
Figure 1.3 Conceptual Model of HAOP Invasion Pathway…………………………… 7
Figure 1.4 Impacts over time of major Oil Spill versus Aquatic Bio-invasion……….10
Figure 1.5 Illustration of Ballast Water Exchange………………………………….. 15
Figure 1.6 Summary of IMO BWM Performance Standard Requirements………….17
Figure 1.7 Summary of the IMO BWM Convention Implementation Schedule……. 18
Figure 2.1 Ballast Water Management Methods for specific Organism Sizes……… 38
Figure 3.1 Map of Nigeria, West Africa………………………………………………40
Figure 3.2 Maps of Niger-Delta Region of Nigeria and Study Area…………………41
Figure 4.1 Relative Zooplankton Density in Sample………………………………….. 51
Figure 4.2 Relative Phytoplankton Density in Sample……………………………… 52
Figure 4.3 Summary of mean and SD of Phytoplankton Density in Study Area…… 53
Figure 4.4 Total Phytoplankton Density as a function of Salinity………………………54
Figure 4.5 Summary of mean and SD of Zooplankton Density in Study Area……….55
Figure 4.6 Total Zooplankton Density as a function of Salinity……………………….. 55
Figure 5.1 Ballast Water Treatment Options: Onshore and Shipboard ………….…58
Figure 5.2 Proposed Onshore BWTS Stages for Port Harcourt Harbour, Nigeria…. 64
Figure 5.3 Proposed Treatment Sequence and Propagule Pressure…………………66
Figure 5.4 Hypothetical Shipping Trade Route between a port in Nigeria and some
ports in North America……………………………………………………..……….. 68
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Figure 5.5 Risk Impact/Probability Chart for proposed BWTS…………………….. 69
Figure 5.6 Port Authority’s Onshore BWM Decision Flow Chart Model……………71
Figure 5.7 Ship’s Onshore Pre-loading BWM Decision Flow Chart Model…………. 73
LIST OF ACRONYMS
ANOVA Analysis Of Variance
BWE Ballast Water Exchange
BWM Ballast Water Management
BWMC Ballast Water Management Convention
BWMS Ballast Water Management System
BWT Ballast Water Treatment
CBD Convention on Biological Diversity
GI Gastro intestinal
HAOP Harmful Aquatic Organisms and Pathogens
IMF International Monetary Fund
IMO International Maritime Organization
ISAC Invasive Species Advisory Committee
LPOC Last Port of Call
MARPOL International Convention for the Prevention of Pollution from Ships
MEPC Marine Environment Protection Committee
MDF Maritime Dependence Factor
MSC Maritime Safety Committee
NOBOB No Ballast On Board
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NPOC Next Port of Call
NRC National Research Council
UN United Nations
UNCED United Nations Conference on Environment and Development
UNCLOS United Nations Convention on the Law of the Sea
UNEP United Nations Environment Programme
WTO World Trade Organization
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CHAPTER ONE
INTRODUCTION
1.1 STUDY AIM AND OBJECTIVE
The aim and objective of this research is to propose a unique ballast water treatment
procedure that best suits the established characteristics of the study area which is Port
Harcourt Harbour in Nigeria and any port with similar environmental characteristics
and also recommend to the International Maritime Organization (IMO) and member
states how the vector management procedure could be employed to curtail the
menace of Harmful Aquatic Organisms and Pathogens (HAOP) on an international
level. These objectives can be achieved by firstly; identifying qualitatively the most
common planktons (non-indigenous and indigenous) and the physicochemical
characteristics of the harbour from the collected sample of port water to establish a
hypothetical baseline for the harbour (i.e. Port Harcourt Harbour, Nigeria). Secondly,
it will be essential to determine the best mix of shore treatment procedures/systems
for the harbour from the port-specific baseline information of the collected port
ambient water samples and from literature reviewed on ballast water treatment
research. This is because of the expected diversity of aquatic organisms and
differences in physicochemical characteristics of harbours and also the expected
variance in organism’s response to different treatment methods (as established by
research literature). Thirdly, it will be necessary to determine the best sequence to
administer the vector management procedure for the harbour before the transport
vector (i.e. port water) is uploaded as ballast water into the ship.
It is hoped that the achievement of these objectives will significantly minimize the
role of ships and ballast water as vectors of Harmful Aquatic Organisms and
Pathogens (HAOP) without compromising ship safety. It is also envisaged that this
will satisfy the five IMO Regulation D-5.2 requirements of safety, environmental
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acceptability, technical feasibility, practicability, and biological and cost
effectiveness for all treatment systems or technologies (IMO, 2005).
1.2 THE LIMITATION OF THE STUDY
The following limitations were encountered during this study:
1) There is the absence of literature on harbour water baseline for Port Harcourt
Harbour which is located on the Bonny estuary of Nigeria, hence it is difficult to
compare the present results with those from previous investigations.
2) There is a lack of established sampling protocols and methodology on ballast water
research.
3) The absence of a competent scientific laboratory for analysis and tests to quantify
and verify anticipated results is a limitation to the attainment of the objectives of the
study.
4) There is a very limited time frame to conduct more thorough research to establish the
harbour’s baseline, especially for the two prevalent seasons in the study area, i.e. dry
and wet season.
5) There are inherent difficulties in indicator microbes identification and enumeration
as appropriate test equipment were not readily available. Also, traditional pathogen
indicator tests (coliform and E. coli tests) were discovered by Miskowski, Charlie &
Dobranic (2012) not to be effective pathogen indicators because they were not
consistently accurate due to the die-off of the organisms outside the gastrointestinal
(GI) system.
6) The sample site (Port Harcourt Harbour, Nigeria) is remotely located from the World
Maritime University and thus difficult to access.
1.3 BACKGROUND
Shipping is the heart of international trade as most of the world’s trade depends on
shipping. Today more than 90% of all worldwide trade goods are transported on the
ocean and via shipping (IMO, 2009). The Maritime Dependence Factor (MDF) of
Nigeria, for example, is 19% based on 2004 IMF and WTO data (Shuo, 2011)
making the country a relatively high shipping dependent country with ship bornetrade constituting over 80% of the country’s trade.
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In the bid to move cargo, ships tend to transfer around the world’s ocean
approximately 3 to 5 billion tons of water known as Ballast Water each year (IMO,
2001). For ships to travel safely, they must maintain a correct immersion level by
either carrying cargo, ballast or both (Minchin, 1997). Ballast is any material used by
ships or floating objects to maintain balance (GLOBALLAST, 2012). Prior to the
advent of ships that used water to maintain balance, ships/vessels carried solid ballast
that ranged from sand, rocks or even metal for many years. In modern times, ships
use water as ballast because it is much easier to load on and off a ship, and is,
therefore, more efficient and economical than solid ballast (GLOBALLAST, 2012).
1.3.1 What is Ballast Water?
Ballast water is the water used by ships to achieve a correct immersion level and to
maintain balance. Ships use ballast water to provide stability, bouyancy and
manoeuvrability during a voyage and the water is drawn into the vessel by intake
pumps located in the hull, below the waterline. In rough conditions, and when the
ship ballast water is at less than maximum cargo load, either during a transit to pick
up a product, or after dropping off a portion of the cargo before continuing on to the
next port, ballast water is taken on to provide stability and maneuverability for the
ship (Deacutis & Ribb, 2002). The water is taken on at one port when cargo is
unloaded and usually discharged at another port when the ship receives cargo as
illustrated in Figure 1.1.
The propellers of ships carrying little or no cargo could be exposed above water
because the vessel will tend to ride high in the water, making her vulnerable to being
knocked about by heavy weather conditions and increasing the potential for
slamming the bow or stern over high waves and making manoeuvrability impossible.
Therefore, this gives rise to the need to lower the ship to a safer and efficient
immersion level to remedy the potential risk factor.
A typical ballast water tank in a ship could take water that can be between 30 to 50%
of the overall weight of the ship and that represents between 13 to 32 thousand
metric tons of water, depending on the size of the ship (GLOBALLAST, 2012).
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1.3.2 Why is Ballast Water a Problem?
The IMO regards the introduction of Harmful Aquatic Organisms and Pathogens
(HAOP) to new environments via ballast water, as one of the four greatest threats to
the world’s oceans (Xie & Chen, 2004). Harmful Aquatic Organisms and Pathogens
(HAOP) are species that are not native to an ecosystem and cause or are likely to
cause economic or environmental harm or harm to human, animal, or plant health
(Invasive Species Advisory Committee (ISAC), 2006).
Any species removed from its native range and introduced to a new area has the
potential to become an harmful aquatic organism (Veldhuis, Hallers, Riviere, Fuhr,
Finke, Steehouwer, Star & Sloote, 2010).
The problem of HAOP was ranked second only to habitat loss as the major threat to
marine biodiversity by the 2007 Report of the UN Secretary General on Oceans and
the Law of the Sea (Scott, 2008) and their impacts are often irreversible (California
Environmental Protection Agency, 2002). Although other methods have been
identified by which organisms are transferred between geographically separated sea
areas, ballast water discharge from ships appears to have been prominent among
those identified (Rigby & Taylor, 1999; Humphrey, 2008). Ballast water discharges
are known to be the single largest source of introduction of HAOP into new
environments (Amoaka-Atta & Hicks, 2002). It is estimated that more than 3,000
species of animals and plants are transported daily around the world in ballast water
(NRC, 1996). At least one foreign marine species is introduced into a new
environment every nine weeks (Akeh, Udoeka, Ediang & Ediang, 2005).
Ruiz & Carlton (2003) argue that these biological invasions are ‘a potent force of
change’ that is changing Earth’s ecosystems structure and functions. This has created
substantial environmental, health and economic impacts on ports and other water
resources.
The amount of ballast water held on a ship is dependent on the amount of cargo it is
carrying. Figure 1.1 shows a typical ballast water cycle of a ship where the ship loads
ballast water after discharging cargo at the source port or last port of call (LPOC) in
a process known as ballasting and discharges same at the destination port or next port
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of call (NPOC) in a procedure known as deballasting. The end result of these shipsafety procedures (ballasting, reballasting and deballasting) is that when this ballast
water is pumped into the ship it also loads on-board many of the organisms living in
that port.
Figure 1.1: Cross Section of Ships Ballast Tanks and Ballast Water Cycle
(Source: Globallast, 2004).
Microscopic organisms such as fish larvae or eggs are the ideal size to be sucked into
a ballast tank and transported to the next port of call (NPOC) as illustrated in Figure
1.1. Depending on where the ship takes on ballast water, virtually all organisms in
the water column, either swimming or stirred up from bottom sediments, can be
taken into the ships’ ballast tanks (California Environmental Protection Agency,
2002). Often this process will include a wide variety of animals and plants such as
molluscs, shrimp, fish larvae, sea grasses, phytoplankton, zooplankton, viruses,
bacteria, fungi, protozoans, many types of parasites, pathogenic organisms, egg,
cysts, and larvae of various species (California Environmental Protection Agency,
2002).
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These introduced aquatic species are non-indigenous species that are transported and
released during deballasting operations outside of their traditional range (Figure 1.1).
Non-native species in the absence of predators can increase and displace native
species, and ultimately alter the natural ecosystem. Non-indigenous species that
degrade ecosystem function and benefits are referred to as Harmful Aquatic
Organisms and Pathogens (HAOP). HAOP can completely alter aquatic systems by
displacing native species, degrading water quality, altering trophic dynamics, and
restricting beneficial uses (Kazumi, 2007).
Figure 1.2: Prawn & Clam life-cycles showing Planktonic Stages (Source:
California, 2002).
The potential of species transfer is compounded by the fact that all marine species
have planktonic stages in their life-cycle, which may be small enough to pass
through a ship’s ballast water intake ports and pumps (sea chests) (Raaymakers,
2002). This can be seen from the life cycles of both a prawn and a clam as illustrated
in Figure 1.2.
1.3.3 Invasion Pathway
Humphrey (2008) identified the invasion pathway for HAOP as a multi-step process
in which an organism must pass through a series of phases in order to establish itself
in a new environment as illustrated in Figure 1.3.
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The first phase, initial dispersal, requires that an organism utilizes some form of
natural (i.e. currents, winds and animals) or human-mediated (i.e. shipping and
aquaculture) transfer mechanism to move to a habitat outside its native range
(Humphrey, 2008). An organism will move to the second phase of establishment if it
can survive the voyage in the ship’s ballast water tank.
Figure 1.3: Conceptual Model of HAOP Invasion Pathway adopted by
Humphrey (2008) from source: Moyle and Light (1996).
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The second phase (establishment phase) requires that an organism establishes itself
in its new environment and is able to persist through local reproduction and
recruitment (Humphrey, 2008). Whether an organism is able to establish itself,
according to the author will depend on the ecological resistance of the new
environment and this includes: environmental suitability such as temperature or
salinity; biotic resistance such as prey availability, predation, competition, disease
and parasites; and demographic resistance such as numbers or organisms introduced
and reproduction otherwise referred to as propagule pressure.
Propagule pressure (PP) according to Ricciardi, Jones, Kestrup and Ward (2011) is
the most important determinant of establishment success, which means that
establishment is a game of numbers. The propagule pressure theory asserts that the
potential of invasion of species is contingent on the individual number introduced
and the frequency of such introductions into a new environment. This assertion is
supported statistically by the concept of the ‘tens’ rule; this shall be discussed in the
next section, integration.
Integration is the final phase of the invasion pathway; it requires that the newly
introduced species be able to either be self-propelled, or utilize transport vectors to
spread within its new habitat (Humphrey, 2008). The release of non-indigenous
species into a novel environment constitutes their inoculation but not necessarily
their introduction (NRC, 1996) since not all become, ‘invasive’. Some fail to thrive
in their new environment and die off naturally, others survive, but without destroying
or replacing native species (Lovell & Stone, 2005). This phenomenon was explained
succinctly by the ‘tens rule’.
The ‘tens rule’ is a generalization about invaders by Williamson and Fitter (1996)
where they propounded a statistical approach to study the proportion in which
organisms achieve success in new environments. The rule suggests that of the initial
pool of species transported to a new environment, only 10% of these species become
introduced, only 10% of those introduced become established and only 10% of those
established become invasive. Since the ‘tens rule’ have been used in the past to
successfully predict the fate of introduced birds, terrestrial plants and insects, using
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the principle of substantial equivalence, the same rule can also be applied in the
prediction of the fate of introduced aquatic species in a new environment.
1.3.4 Ballast Water Hazard
The introduction of HAOP into a new port environment could constitute a ballast
water hazard. Hazard is the potential of a substance, person, activity or process to
cause harm. According to Jalonen and Salmi (2009), hazard is a condition or
physical situation with a potential for an undesirable consequence, such as harm to
life, environment or property.
The substance here with the potential to cause harm to our coastal environments is
ballast water and the activity is shipping. Hayes (1998) identified two hazard
components of the introduction cycle of HAOP into a port:
a) The taxonomic hazard component-is that set of organisms which is available to
vessels ballasting in a particular port, and are capable of surviving the ballasting
procedure and the vessel’s journey. In this example, the universal set is defined as
the complete floral and faunal assemblage in the donor port.
b) Vector hazard component- consists of those vessels which harbour viable non-native
species. The universal set in this instance consists of all vessels on a given route.
Hayes (1998) here identified aquatic species and ships as hazards or substances that
have the potential to cause harm to a receiver port and environs. Ballast water
treatment or management can, therefore, be said to be a hazard management process.
1.3.5 Risk Assessment of HAOP Invasion
The Risk of an HAOP invasion can be defined as the product of the consequences or
impacts resulting from the invasion of an environment by the HAOP transported in
the ballast water tank of a ship and the probability (i.e. the likelihood) of such an
invasion occurring. The two components in assessing risk, therefore, are
consequences (impacts) and probability (likelihood).
Risk= Probability x Consequence
1.3.5.1 Probability of HAOP Establishment
The probability elements of HAOP establishment in a new environment according to
Orr (2003) are: entrainment potential (i.e. probability of organism being in the ballast
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water), entry potential (i.e. probability of organism surviving the voyage),
colonization potential (i.e. probability of colonizing and maintaining a population)
and spread potential (i.e. probability for natural dispersal).
Some examples of the consequences or impacts of HAOP (economic, environmental
and health), which are necessary components in risk assessment, shall be discussed
in the next section.
1.3.5.2 Consequences or Impacts of HAOP Invasion
The introduction of marine species into new environments by ship’s ballast water
attached to ship’s hulls and via other vectors has been identified as one of the ‘four
greatest threats to the world’s oceans’ by the IMO (GLOBALLAST, 2004; IMO,
2005). The other three are land based sources of marine pollution, overexploitation
of living marine resources and physical alteration/ destruction of marine habitat
(United Nations, 2002; Hillman, Hoedt & Schneide, 2004).
Figure 1.4: Impacts over time of major Oil Spills versus Aquatic Bio-invasions
adopted from Source: Raaymakers (2002).
Unlike other forms of marine pollution, such as oil spills, where ameliorative action
can be taken and from which the environment will eventually recover as illustrated in
Figure 1.4, the impacts of HAOP are most often irreversible (IMO, 2001;
Raaymakers, 2002) and generally increase in severity over time because of their
ability to reproduce.
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Much of this translocation takes place via ships’ ballast water and can lead to very
high economic and environmental costs (Hillman et al., 2004). HAOP, once
established in a new environment, are always very difficult and cost prohibitive to
control and almost impossible to eliminate. There is, therefore, a need for ballast
water management programmes to be established in every port (host port).
Ecological Impacts
Some examples of ecological impacts are: predation (preying on native species),
parasitism, competition (competing with native species for space and food), altering
the food web and the overall ecosystem, introduction of new pathogens, species
shifts/loss of biodiversity-displacing native species, reducing native biodiversity and
even causing local extinction (Deacutis & Ribb, 2002; Raaymakers, 2002).
Economic Impacts:
HAOP invasion could impact negatively on commercial and recreational fishing
through a reduction in fisheries production. This according to Raaymakers (2002)
could be due to competition, predation, or displacement of the native fishery species
by the invading species, or through habitat environmental changes caused by the
invading species. Fouling of ship’s hull by HAOP could lead to a reduction in the
operational efficiency of ships. Fouling of beaches by HAOP such as algae could
result in foul odour from algae bloom which could lead to the closure of recreational
sites such as beaches, damaging the local economy of developing nations.
There are secondary economic impacts from human health impacts of introduced
pathogens and toxic species, including increased monitoring, testing, diagnostic and
treatment costs, and loss of social productivity due to illness or even death in persons
affected (Raaymakers, 2002). Filter feeders like the zebra mussel and the red king
crab, Paralithodes camtschaticus can increase water clarity, thereby increasing the
economic utility of water bodies around recreational sites such as beaches.
Public Health Concerns:
Ballast water has been recognized by the World Health Organization (WHO) as a
vector for disease causing pathogens as well as food poisoning from one region of
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the world to the other. Some examples of the public health concerns from ballast
water are:
1) Risk of Cholera disease: ship ballast can carry the Vibrio cholerae (the bacteria that
causes cholera disease), concealed in plankton, to estuaries around the world from
polluted harbours and bays. Ballast water was perhaps the vector responsible for the
transfer of the cholera strain from Asia to Latin America in 1991, which was then
spread to Mobile Bay, Alabama, USA where it was found in oysters in closed
shellfish bed.
2) Harmful Algal Bloom (HAB)- algal blooms may result due to the transoceanic
introduction of harmful algae through ships’ ballast discharge and this may be
responsible for producing the toxin known as Paralytic Shell Fish Poisoning (PSP)
which causes illness in humans and even death (Deacutis & Ribb, 2002).
Global Impacts of Harmful Aquatic Organisms Pathogens;
Between US$ 750 million and US$ 1 billion was expended between 1989 and 2000
to control the infestation by the European Zebra Mussel Dreissena polymorpha of
over 40% of the internal waterways in the USA (GLOBALLAST, 2004). Between
2000 and 2006, over $7 million was spent to eradicate the Mediterranean green
seaweed (Caulerpa taxifolia) from two embayments in southern California
(Dobroski, Scianni, Gehringer & Falkner, 2009) and approximately $10 million is
spent annually to control the Sea Lamprey (Petromyzon marinus) in the Great Lakes
(Dobroski, et al., 2009). By 2010, over $12 million had been spent in San Francisco
Bay to control the Atlantic cordgrass (Spartina alterniflora) (Dobroski, et al., 2009).
In the Black Sea, the filter-feeding North American jellyfish Mnemiopsis leidyi has
depleted native plankton stocks to such an extent that it has contributed to the
collapse of entire Black Sea commercial fisheries (IMO, 2001; GLOBALLAST,
2004).
In several countries, introduced, microscopic, ‘red-tide’ algae (toxic dinoflagellates)
have been absorbed by filter-feeding shellfish, such as oysters. There were cases of
death that followed the consumption of bivalve molluscs that have filter-fed on toxic
marine microalgae (phytoplankton). The toxic microalgae were recorded in Alaska in
13
2010 and major toxic blooms have occurred in Tasmania, Victoria and South
Australia (IMO, 2001).
Over 200 indigenous fishes were extinct in Lake Victoria as a consequence of
invasion by the Nile Perch (Lates niloticus) since it was introduced in the 1950’s
(Humphrey, 2008).
The financial implication of the menace of HAOP is monumental across the globe. In
the United States of America, for example, the annual cost associated with all
identified HAOP is estimated at over $138 billion (Kazumi, 2007; Dobroski et al.,
2009). This estimate does not include the effects of species’ extinction, losses in
biodiversity, ecosystem functions, and aesthetics, which are difficult to measure
monetarily (Kazumi, 2007).
Nigeria is not exempted from this international problem as the country has had her
fair share of HAOP occurrences. An example is the yearly invasion of the coastal and
navigational water ways by a harmful aquatic organism known as Water Hyacinth
(Eichhornia crassipes), which has, according to Fournier (2004), an ‘aesthetic cost’
because it makes our beaches unattractive to tourists. It also blocks the water ways
for fishing activities and for incoming and outgoing ships resulting in delay to ships
and thereby raising freight costs.
The HAOP list of impacts continues to grow with several examples of major
ecological, economic and human health impacts across the globe (see Appendix D
for list of some impacts).
1.3.6 International Efforts
In response to the threat posed by invasive marine species, the United Nations
Conference on Environment and Development (UNCED) held in Rio de Janeiro in
1992, in its Agenda 21 called on the IMO and other international bodies to take
action to address the transfer of harmful organisms by ships.
Furthermore, on Friday 13 February 2004 at a diplomatic conference in London, the
IMO adopted by consensus ‘The International Convention for the Control and
Management of Ships Ballast Water and Sediments’. In 2005, the Maldives, Nigeria,
St Kitts and Nevis, Spain and Syrian Arab Republic were the first countries to ratify
14
the convention (GLOBALLAST, 2004; Hillman et al., 2004; Kazumi, 2007). By
August 2007, the convention had only been ratified by 10 countries that represent
3.4% of the world shipping tonnage (McMullin, 2007). As at the time for the sixtyfourth session of the MEPC in October, 2012, 36 States, with an aggregate merchant
shipping tonnage of 29.07 per cent of the world total, have ratified the Convention.
35% of world tonnage and 30 national ratifications are required for the convention to
come into force.
This convention requires two management procedures to be employed by ships in
managing and controlling the menace of ballast water discharge around the world;
Ballast Water Exchange Standard (Regulation D-1) and Ballast Water Performance
Standard (Regulation D-2). There is also a stipulated year of implementation for the
various sizes of ballast water tanks and year of construction of ship.
The most widely adopted management procedure is Ballast Water Exchange (BWE)
also known as Mid-Ocean Exchange (MOE). The BWE process entails the
replacement of the biologically rich water of the coastal environment loaded at the
port with the comparatively species and nutrient-poor waters of the mid-ocean
(Dabroski et al., 2009). As a consequence of the difference in biology (competition,
predation, food availability) and oceanography (temperature, salinity, turbidity,
nutrient levels) between coastal and mid-ocean environments, coastal organisms used
to the coastal conditions are not expected to thrive in mid-ocean conditions
(Dabroski et al., 2009). The IMO over the years has recommended BWE as a stopgap
panacea to the problem posed by the translocation of Harmful Aquatic Organisms
and Pathogens (HAOP) (Hillman et al., 2004).
An illustration of a typical BWE is shown in Figure 1.5, where a hypothetical ship
(an oil tanker) leaves position A, the Port of Halifax, in central Nova Scotia, Canada,
travels through the Great Lakes to position B, the Port of Miami, in Florida, United
States, where she discharges her cargo and takes up ballast water prior to crossing the
Atlantic Ocean on a voyage to Nigeria, West Africa. BWE would occur at position C
in the Atlantic Ocean prior to the ship entering Nigeria’s territorial waters to pick up
cargo (crude oil) from position D, Port Harcourt Port, in Nigeria for transport to the
15
receiving port in position E on the Great Lakes that is the Port of Oswego, New
York, in the United States.
Figure 1.5: Illustration of Ballast Water Exchange.
Coastal ballast water is replaced with open ocean water during BWE by one of two
methods: (i) flow-through exchange or (ii) empty-refill.
a) Flow-through exchange means to flush out ballast water in a ballast water
tank by pumping in oceanic water at the bottom of the tank and overflowing
the ballast water tank from the top in other to exchange up to three full
volumes of water, to minimise the number of organisms remaining in the tank
(Waite & Kazumi, 2001a).
b) Empty/refill exchange means to pump out the ballast water taken on in ports,
estuarine or territorial waters until the tank is empty, then refilling it with
mid-ocean water (Waite & Kazumi, 2001a).
Changing ballast water may be an acceptable and effective control method under
certain circumstances, but it is neither universally applicable nor totally effective,
and alternative strategies are needed (NRC, 1996). Research has demonstrated that
the percentage of ballast water exchanged does not necessarily correlate with a
proportional decrease in organism abundance (Dobroski et al., 2009, Ruiz, Smith, &
Systma, 2006). For example, experimental and computational fluid dynamics (CFD)
16
methods used by Wesley, Chang, Verosto, Atsavapranee, Reid and Jenkins (2006) to
examine the flow behaviour inside ballast tanks during BWE and to examine the
exchange efficiency, showed that the predicted exchange efficiency did not meet
IMO’s required 95% replacement after three tank volume exchanges for the
particular tank geometry that was simulated. It was also clear from Wesley et al.
(2006) that perfect mixing assumptions are not valid for exchange efficiency. In
another study by Ruiz and Reid (2007) on commercial oil tankers, no difference was
found between 100% empty-refill and 300% flowthrough BWE in removing coastal
water from ballast tanks, as both methods removed 99% of added dye tracer. The
latter had a lower efficacy in removing coastal zooplankton, as the results were more
variable than observed for empty-refill exchange: however, both methods had
efficacies > 90% on average for coastal zooplankton.
Regulation D-2 or Ballast Water Performance Standard, is a concentration-based
discharge standard for organisms in ballast water adopted by the IMO in 2004. This
regulation requires the introduction of ballast water treatment methods that will meet
the requirements of IMO standards for ballast water discharge. The requirements of
the standard are far more stringent than the requirements of the Ballast Water
Exchange standards and numerically quantitative in nature.
1.3.6.1 Some Ballast Water Management (BWM) Regulations (IMO, 2005).
The two ballast water discharge standards; D-1 (ballast water exchange) and D-2
(ballast water treatment) as defined by the BWM Convention are as follows:
Regulation D-1: Ballast Water Exchange Standard
Regulation D-1 requires performance of ballast water exchange with 95% volumetric
efficiency at a location at least 200 nautical miles offshore and in at least 200 m
depth of water or at a location at least 50 nautical miles offshore and in at least 200
m depth of water.
Regulation D-2: Ballast Water Performance Standard
Regulation D-2 requires ballast water treatment results to have less than 10 viable
organisms per cubic meter for organisms of size greater than or equal to 50 microns
17
and less than 10 viable organisms per milliliter for organisms of size less than 50
microns. Less than one colony-forming unit (cfu) of toxicogenic vibrio cholerae per
100 ml or less than one cfu per gram (wet weight); less than 250 cfu of Escherichia
coli per 100 ml; and less than 100 cfu of intestinal enterococci per 100 ml as
summarized in Figure 1.6.


Figure 1.6: Summary of the IMO Ballast Water Performance Standard
Requirements (Source: adopted from IMO, 2005).
Due to limited biological efficiency as stated earlier, the Exchange Standard (D-1)
is regarded as an interim measure or a stop gap. Compliance with the Performance
Standard (D-2) seems to be achievable only by use of a Ballast Water Treatment
System (BWTS).
Regulation B-3 Ballast Water Management for Ships:
For ships constructed before 2009, D-1 or D-2 must be conducted, while for those
constructed in or after 2009; D-2 must be conducted. For those with ballast water
capacity between 1500 and 5000 m3
, D-2 must be conducted from 2014. 2016 is the
D-2 enforcement year for those with capacity of less than 1500 or greater than 5000
m
3
(IMO, 2005; see also Appendix F for full text of relevant BWM regulations). The
BWM Convention implementation schedule is summarised in Figure 1.7.
18 



Figure 1.7: Summary of the IMO Ballast Water Convention Implementation
Schedule (Source: ABS, 2012 from IMO, 2005).
1.4 PROBLEM STATEMENT
The Convention on Biological Diversity (CBD) recognizes five major threats to
biodiversity: habitat change, loss and fragmentation; harmful aquatic organisms
(bio-invasion); overexploitation; pollution and nutrient loading; and climate change
and global warming (United Nations, 1992a; INTOSAI, 2007).The IMO on the other
hand sees HAOP as one of the four greatest threats to the world’s ocean. According
to Akeh et al. (2004) at least one foreign marine species is introduced into a new
environment every nine weeks, meaning that without effective management systems
in place, about six species will be introduced into that environment in a year.
The IMO has identified ballast water as an important vector for the transfer of
Harmful Aquatic Organisms and Pathogens (HAOP) globally. It acts as an
inoculation mechanism for these nuisance species (NRC, 1996). During sea
transport, millions of animals or plant organisms are transported in the ballast water
and are taken to alien environments. Many of these species according to studies can
survive in the ballast water and sediment even after journeys of several weeks
resulting in the species becoming established and ultimately becoming invasive
which can seriously alter the existing ecological status quo (INTERTANKO, 1997).
19
The potential for ballast water discharge to cause harm has been recognised not only
by the IMO, but also by the World Health Organization (WHO) which is concerned
about the role of ballast water as a medium for the spread of epidemic bacterial
disease (INTERTANKO, 1997; California Environmental Protection Agency, 2002).
When ballast water is discharged into a new environment, the non-native organisms
released during the discharge can survive if the new environment is similar to their
native environment. Non-indigenous species are, therefore, introduced into the local
ecosystem where they can proliferate or mutate unhindered (Hydac, 2008). In the
absence of natural competition or predators, these non-native organisms could thrive
and outgrow the native species.
There are documented facts of these impacts in different parts of the world, some
examples were enumerated earlier. Unfortunately, the same cannot be said about
Nigeria, as the issue of ballast water as a source of marine pollution remains largely
an un-researched and un-documented field of interest.
Although prevention of the spread of HAOP is not possible with the extensive trade
around the world, some practical management measures, if undertaken, will certainly
reduce the overall risk (Minchin, 1997). The IMO has had ballast water issues on its
agenda for some years now. However, to date, limited progress has been made with
regard to the development of processes and procedures for halting the transport of
unwanted species via ships’ ballast.
Regulation D1 as noted earlier has obviously not been satisfactory in minimizing the
transfer of HAOP. Some invasive species have succeeded in slipping through the
cracks in the system, and this has continued the contamination process in new port
environments. There is still no universally applicable option for controlling ballast
water that can totally prevent the unintentional introduction of HAOP (NRC, 1996).
More research on ballast water management (BWM) is, therefore, needed to identify
new methods, systems, management styles or procedures to reduce this menace to a
sustainable level that will satisfy IMO’s requirements for treatment systems in
Regulation D-5.2 for safety, environmental acceptability, technical feasibility,
practicability, biological and cost effectiveness (IMO, 2005). This study’s
20
overarching objective is the identification of such management systems that will
meet most if not all of the requirements of IMO.
1.4.1 Management of Harmful Aquatic Organisms (HAOP) Invasions
According to Mack, Simberloff, Lonsdale, Evans, Clout, and Bazzaz (2000), the
management of aquatic invasions can be divided into four stages:
i) Identification,
ii) Prevention,
iii) Eradication, and
iv) Control.
Identification is recognized by the scientific community as the first step in HAOP
management, largely because of the diversity of species and their different responses
to different treatment methods (Humphrey, 2008). Prevention, according to
Wittenberg and Cock (2005) is the first and most effective defence against HAOP.
This study will focus on the identification and prevention stages of the HAOP
management which are obviously the first lines of defence against HAOP
introduction.
Ballast Water Treatment (BWT), therefore, remains the best available management
procedure that can address the identification and prevention stages and also
outperform ballast water exchange (BWE) and meet the requirements of IMO’s
Performance Standard, provided the range of HAOP in the study area are identified,
as each specie responds to different treatments differently.
Aside from the BWM Convention of the IMO, other international instruments such
as article 8(h) of the Convention on Biological Diversity (CBD) and Article 196 of
the United Nation’s Convention on the Law of the Sea (UNCLOS) also mentioned the
need for parties to prevent and control the introduction of HAOP in their jurisdictions
(see Appendix F for full text of conventions).
In response to this, quite a number of research efforts have been made around the
world on the issue of the translocation of harmful aquatic organisms via ship’s ballast
water and on the treatment options for different species in order to reduce and control
21
their introduction into new environments. A review of some research work on the
subject matter is the objective of the next chapter.

22
CHAPTER TWO
REVIEW OF RELATED RESEARCH

The discharge of ballast water is the single largest known source of introduction of
HAOP into new environments (Amoaka-Atta & Hicks, 2002). The uncontrolled
discharge of ballast water and sediments from ships has led to the transfer of HAOP,
causing injury to public health and damage to property and the environment (Pavliha,
David & Andrijasic , 2003).
According to Waite and Kazumi (2001a), the ballast water issue is ‘an invasive
species problem’. Management focus is on the prevention of invasions by organisms
substantially larger and more biologically complex than bacteria or viruses. This
human-mediated transfer of organisms across the globe according to Ruiz et al.
(2006) is a ‘potent force of change’ and once established, HAOP populations can
become numerically or functionally dominant in invaded communities.
2.1 LITERATURE REVIEW OF SOME PHYSICOCHEMICAL
PARAMETERS OF BONNY AND CONTIGUOUS RIVERS IN NIGERIA.
The study of physical and chemical characteristic of water is very important as they
may directly affect its quality and suitability for utility, and productivity of aquatic
organisms (Swingle, 1969; Moses, 1983). The abundance and distribution of the
organism can be influenced by the physical and chemical qualities of water. Oyewo
and Don Pedro (2003) reported that variability of water quality influences the
toxicity of trace heavy metals on estuarine organisms as it affects the physical and
chemical composition of the ecosystem.
The physicochemical report of Okpoke creek, off Bonny river system of Niger-Delta,
Nigeria (George, 2009 cited in Oyewo & Don Pedro, 2003) revealed that surface
23
water temperature ranges between 28.98oC-29.77oC, pH (6.68-7.03), salinity (4.75-
12.65ppt), DO (3.72-5.10mg/l), BOD (1.97-2.69mg/l) and electrical conductivity
(10788.75-24877.92). Also, Tyokumbur, Okorie and Ugwumba’s (2002) research
results revealed that mean water temperature varied between 25.8oC- 32.5oC, DO
(1.4mg/l-8.0mg/l), Hardness (119.7-100.4mg/l), CO2 (30.0-52.2mg/l) while trace
heavy metal concentrations showed slight variations with the following ranges;
copper (0.29-0.31mg/l), zinc (0.38-0.48mg/l) and lead (0.65-2.03mg/l), all values
were below Nigeria’s National Environmental Standards and Regulations
Enforcement Agency (NESREA) guidelines.
In Bonny River, Niger-Delta, Dublin-Green (1990) gave the results of some physicochemical variables, for surface water in wet and dry seasons as temperature (27.5-
31.2oC), conductivity (30800-45500ms/cm), pH (7.7-7.6), salinity (25%-30%), DO
(6.0-52mg/l), and total alkalinity ( 90.0-12mg/l). It has been stated by some
environmentalists such as NEDECO (1980), Dangana (1985) and Zabbey (2002) that
in the Bonny estuary of the Niger-Delta, the physicochemical parameters such as
electrical conductivity, dissolved oxygen, pH, temperature, salinity and tidal range
vary seasonally. In a study conducted by Mitchell-Innes and Pitcher (1992), changes
in abundance of organisms are related to changes in physicochemical parameters of
the water body.
2.1.1 Water Temperature
In general terms, temperature may be defined as the degree of hotness or coldness in
a body (Lucinda & Martin, 1999). It can also be defined as the condition of a body
which determines the transfer of heat to or from another body. Temperature is
usually measured either by mercury-in-bulb thermometer or thermistor in Celsius
(
oC). Physical, biological and chemical processes in surface and sub-surface water
are influenced by temperature (McNeely, Neimanis, & Dwyer, 1979). A rise in water
temperature may lead to reduction of solubility of oxygen in water thereby increasing
the oxygen demands of fish. Higher temperatures increase the solubility of many
chemical substances and may influence the effect of pollution on the aquatic system.
Boyds reported in 1979 that temperature affects the physical, chemical and biological
24
processes in surface water thereby increasing the concentration of dissolved oxygen
and photosynthetic activity.
Variation of surface water temperature depends on latitude, elevation, season, period
of the day, wind, wave action or water current, depth, cloud/vegetation cover among
others. It is also subject to season. Meanwhile, McKee, Levi, and Movshon (2003)
reported that an increase in water temperature may lead to reduction of aquatic plants
and increase the population of phytoplankton organisms.
Aquatic organisms have both an upper and lower temperature limit for proper
growth, spawning, egg incubation and migration depending on the species. Boyd and
Lichkoppler (1979) reported that the rate of biochemical reactions doubled with
every 10oC rise in temperature. Fish have been reported to grow faster at
temperatures between 25oC- 32oC (Parker & Davis, 1981; Sikoki & Venn, 2004).
High temperature or sudden changes are often dangerous to fish. These limits vary
from species to species. Changes in temperature regime may therefore alter the
distribution and species composition of aquatic communities. Fish had ecologically
been classified according to their ability of tolerance to temperature as stenothermal
“lower” or eurythermal “higher” (Boyds, 1979)
Temperature ranges between 27-31oC were recorded by Hart and Chindah (1998) in
the mangrove swamp of the Bonny estuary, whereas Sikoki and Zabbey (2006)
reported a narrow temperature range of between 26.0-27.8oC. Ademoroti (1996)
reported that water temperature can strongly affect feeding patterns, growth rate and
breeding periods of aquatic organisms. Miserendino (2001) observed that species
richness was positively correlated with temperature and altitude.
2.1.2 pH levels
pH indicates a balance between the acids and base in water. It is a measure of the
hydrogen ion concentration in a solution. The value of pH reflects the solvent ability
of water. The pH values of water are measured on a scale ranging from 0 to 14. The
pH values below 7 are an indication of acidic conditions and values greater than 7
indicate alkaline conditions in water. The range of pH in natural fresh water varies
from 4-9. It is controlled by bi- carbonates in the aquatic system. The general trend
25
of surface water tends to be alkaline, whereas ponds and swamps are more acidic.
The range of pH in fresh water is greater than that of sea water. Sea water values, for
example, range from 8.0 to 8.3 pH units. pH is considered an ecological factor,
which has a strong relationship with the physiology of most aquatic organisms
(Boltovskoy & Wright, 1976; Boyds, 1979).
Water pH is usually measured by the use of an inglass meter with electronic glass
electrode. Boyd and Lichkoppler (1979) observed an increase in surface water pH
during the day and decrease at night due to the temporary removal of bicarbonates by
aquatic macrophytes during photosynthesis. The pH of water may influence the
species composition of an aquatic environment and affect the availability of nutrients
and the relative toxicity of many trace elements. Chindah, Braide and Izundu (2005)
reported pH range from acidic to slightly above neutral for both dry and wet seasons
in the surface brackish water wetland embayment of the Bonny River.
2.1.3 Electrical Conductivity
The conductivity of a water system is an index of the total ionic content of that
water; thus it provides an index of the freshness or ionized electrolytes in water. It is
usually measured in scale and expressed as micro Siemens per centimeter (µscm-1
).
The general trend of conductivity values of 1000µscm-1
indicates fresh water; above
40,000µscm-1
are marine waters while those between the two values indicate
brackish water. Conductivity values can be used to explain productivity of an aquatic
system both chemically and biologically.
Conductivity varies according to season. A conductivity value of 900-15000 for dry
season indicates greater sea influence in the dry season than in the wet season
(Chindah et al., 2005). The values of conductivity recorded by Chindah et al. (2005)
in a brackish wet-land embayment of the Bonny estuary differs significantly between
seasons (P<0.05). Total density of macro-invertebrates in the Andean Ptagonian
River and streams were correlated with conductivity, temperature and altitudes
(Miserendino, 2001).
26
2.1.4 Salinity
Salinity is the total sum of all solid substances in solution contained in 1 kg of water.
It is usually measured and expressed in scale weight of salt per volume of water. The
unit of measurement is grams per liter (gm/l) or parts per thousand (PPT). Similarly,
it could also be measured as parts per million (PPM) or percentage of salt (%).
Salinity is an important factor in the life of aquatic organisms. A slight variation in
salt content of any aquatic ecosystem may subject organisms to serious stress
conditions especially in a situation where the internal fluids of the organisms are not
in balance with the external salinity of the water where they live. The distribution,
abundance and composition of species may be affected or influenced by salinity
(Pombo, Elliot & Rebelo, 2005).
Water with a salinity level between 0.5-30percent had been classified as brackish,
while between 30 and slightly above 34% is referred to as marine water. Romane and
Schlieper (1971) stated that salinity is the major environmental factor restricting the
distribution of marine and lacustine taxa, resulting in pronounced decrease in species
of aquatic organisms in brackish water. Jones (1987) also reported a relationship
between the number of individuals and salinity. He concluded that changes in oxygen
and sediment were of less importance than salinity influencing the benthic
communities of Hawkesbury estuary. Hart and Chindah (1998) recorded a salinity of
12.5-26% in the mangrove swamp of the Bonny estuary.
2.1.5 Turbidity
Turbidity is the measure of the suspended particles such as silt, clay, organic matter,
plankton, and microscopic organisms in the water held in suspension by turbulent
flow and Brownian movement (O’Neill, McKim, Allen & Choate, 1994). It is
determined by comparing the optical interferences of suspended particles to the
transmission of light in water using instruments previously standardized for analysis
of samples for standard turbidity units (USEPA, 1999). The unit of measurement is
usually referred to as Natural Turbidity Unit (NTU) or Jackson Turbidity Unit (JTU).
The amount of solid material suspended in water may result from erosion, wind
action, runoff, algal blooms as well as from human activity. Turbidity values vary
27
according to water type, source and season. Egborge (1994) recorded higher values
of turbidity in all stations sampled in wet season months than in dry season months
along the Bonny estuary. This was attributed to surface water runoff during the wet
season.
High turbidity reduces photosynthesis of benthic plants and algae thereby reducing
plant growth and productivity. Rapid increase in turbidity may affect aquatic
biological communities; therefore, turbidity is an important factor in surface water
(McNeely et al., 1979).
2.1.6 Total Dissolved Solids
Total Dissolved Solids (TDS) is an index of the amount of dissolved substances in
water. The presence of such solutes alters the physical and chemical properties of
water. Natural water ways acquire mineral constituents in dissolved form as
dissolved salts in solution such as sodium, magnesium, sulphate, nitrate, phosphate,
and chloride.
The range of dissolved solids varies in different types of surface water as follows: 0-
1,000mg/l in typical fresh water, 1,001-10,000mg/l in brackish water, 10,001-
100,000mg/l in marine and above 100,000mg/l in brine water. The contributing
factors are natural and anthropogenic sources such as high surface runoff, flooding,
municipal and industrial effluents, and agricultural activities (Odokuma &
Okpokwasili, 1996).
2.1.7 Dissolved Oxygen (DO)
Dissolved oxygen is an important gas that is found in natural surface water. Its
solubility in water is very slow as such; it is a factor that limits the life of aquatic
organisms. The amount of dissolved oxygen in natural waters varies according to the
type of water body and seasons. Concentration of dissolved oxygen is dependent on
some key factors of the environment such as temperature, salinity, turbulence of
water, and atmospheric pressure (decreasing altitude). Dissolved oxygen
concentration subject to diurnal and seasonal fluctuations, is due to variations in
temperature, photosynthetic activities that take place in water and river discharge
(Ministry of Environment, Lands and Parks Land Data BC, 1998).
28
Coimbra, Graca, and Cortes (1996) studied the effects of effluents on the macro
invertebrate community in a Mediterranean river and revealed that the effluent
discharge caused a significant decrease in the dissolved oxygen requirement of the
river water and a significant increase in conductivity, sulphate and nitrate. They
observed further that in reference to sites, four species were abundant, whereas in
effluent discharge areas, most of the organisms were replaced by two different
species.
The composition of organic wastes and oxidation of organic products may reduce the
dissolved oxygen levels to amounts equivalent to zero. Macro invertebrate responses
along a recovery gradient of a regulated river receiving an effluent (Carmago, 1992)
reflected greater diversity and total biomass at a station upstream to the discharge
point than at downstream sampling sites where oxygen depletion was pronounced.
Snowden and Ekweozor (1990) studied the littoral fauna of the Bonny River estuary
and reported low density and biomass of enryhaline species recovered in the middle
reaches. They attributed the reduction in density and biomass to oxygen depletion
due to pollution from oil terminals, and outboard engines. Oxygen depletion as a
consequence of oil spillage in the Niger Delta (Bonny estuary) was further
investigated by Snowden and Ekweozor (1987), and they observed a near to total
elimination of littoral in fauna and a highly significant oyster mortality. Mortality of
macro fauna during oil spills and pollution may be directly due to depletion of
oxygen (asphyxia) which could result in death of organisms or total loss of biodiversity and loss of habitat (Ekweozor, 1989).
Swingle (1969) and Moses (1983) both agreed that these physical and chemical
parameters of water are very important determinants of the abundance and
distribution of organisms in marine environments and hence determinants of the
treatment mechanism to be deployed in treating such water. Therefore, the objective
of this study cannot be successfully achieved without the knowledge of these
important characteristics.
29
2.2 USE OF SURROGATE ORGANISMS/ PROXY GROUP
In research to address the diversity of organisms in ballast water, surrogates or proxy
groups were used as representatives of the different taxa. Surrogates are hardy, least
susceptible to treatment and tolerant across a wide range of conditions, such that if
they succumbed most other organisms would be eliminated as well (Ruiz et al., 2006;
Hillman et al., 2004). In a study by Hillman et al. (2004) the pilot plant largely used
existing technologies: filtration, ultraviolet light and chlorine dioxide dosing. The
authors also agreed with Ruiz et al. (2006) that, potential treatment systems should
be tested on surrogate species which are representative of the likely spectrum of
invader types.
In an effort to standardize results, Dobroski et al. (2009) evaluated any data on
zooplankton abundance as representative of the largest size class of organisms
(greater than 50 μm in size). Phytoplankton abundance was evaluated on par with
organisms in the 10 – 50 μm size class and culturable heterotrophic bacteria were
selected as a proxy for total bacterial count because, unlike total bacteria, according
to the authors, there are reliable, well-accepted standard methods to both enumerate
and assess viability of these organisms.
Hillman et al. (2004) ran tests using primarily the brine shrimp, Artemia salina,
which is readily and cheaply cultured, has a tough, encysted stage as well as a stage
where it represents many planktonic organisms as a particularly useful surrogate for
many of the organisms of concern carried in ballast water. The adult Artemia salina
is commonly used as surrogate in many tests.
Voigt and Gollasch (2001) also carried out a research using the same species where
four different life-stages were used: adults, cysts, developing eggs and nauplii, to
cover most of the trophic levels of the organisms usually found in ballast water tanks.
The authors concluded that the cysts of Artemia salina could be used as a surrogate
for the cysts of any species, where treatment chemicals would have to pass a thick
shell to influence the organisms. Peracetic acid was successful on Artemia cysts
while a 25% solution of glutaraldehyde was not (Voigt et al., 2001).
30
Hillman et al. (2004) also ran tests on a rotifer, Brachionus rotundiformes and the
phytoplankton Nanochloropsis. The researchers found out that filtration using 50
micron screens is 100% effective in removing Artemia cysts and nauplii (the newly
hatched animal) and 85% effective for Brachionus.
2.3 REVIEW OF TREATMENT METHODS
In February 2004 in London, it was decided, through the adoption of the BWM
Convention of the IMO, that the treatment of ballast water on ships will be
compulsory from 2009 (Hydac, 2008) but the deadline had to be extended by
Resolution A.1005 (25) to 1st January 2012 because there were uncertainties
regarding the immediate availability of ballast water treatment technology to ships to
which regulation B-.3.3 would first apply, i.e. ships constructed in 2009 (Globallast,
2012).
Physical treatment methods that remove organisms from ballast water such as
filtration and hydrocyclone may be used as primary treatment to be followed by
additional secondary treatment systems, such as exposure to UV or chemical
treatments, to inactivate the remaining load of organisms in the water.
The Marine Environment Protection Committee (MEPC) of the IMO requires ballast
water treatment options to meet the following criteria: they must be biologically
effective, environmentally acceptable, safe for the crew, and cost effective (IMO,
2005). The following treatment methods have been identified: filtration systems,
oxidizing and nonoxidizing biocides, thermal treatment, electric pulse and pulse
plasma techniques, ultraviolet (UV) treatment, acoustic systems, magnetic fields,
deoxygenation, biological techniques, and anti-fouling coatings. Four of these
treatments according to NRC (1996) were identified to have met the requirements for
safety and effectiveness: filtration, biocides, heat, and electric pulse/pulse plasma
systems, and these will be discussed in the following sections.
2.3.1 Filtration and Physical Separation Systems
Physical separation systems are perhaps the most environmentally friendly methods
for the removal of HAOP from water, as they do not leave any residual effect in the
water, which is not the situation with biocides for example. Physical separation
31
methods like filtration and hydrocyclones have limitations as to the sizes of
organisms they can effectively remove (Kazumi, 2007).
a) Filtration: Philips (2006) noted that filtration can effectively remove
ichthyoplankton, zooplankton, larger phytoplankton and heterotrophic protists,
but it has not been successful in reducing the concentration of most
microorganisms. Hillman et al. (2004) observed that the method will be possibly
effective in removing dinoflagellate cysts but it will not remove most of the
organisms since their specific gravity is very close to that of water.
According to Chase et al. (2000) ballast water can be filtered before it enters the
tanks or while it is being discharged. They observed that the advantage of
filtration is that organisms that are filtered out may be retained in their native
habitat. Media filtration using a sand/anthracite filter according to Kazumi
(2007) can remove particles down to 1µm in size, and this has been achieved in
other water treatment processes. The researcher reported that crumb rubber made
from waste tires may be suitable for potential particle separation. Xie and Chen
(2004) observed that for the sand/anthracite filter, the removal efficiencies for
particles larger than 10 μm and 15 μm was 89.4% and 94.5%, respectively, while
for crumb rubber it was 86.8% and 93.6%, respectively.
b) Hydrocyclone: In a research by Rigby and Taylor (1998), hydrocyclone which is
meant to be a substitute to filtration, gave inconclusive test data in small
prototype cyclones. Parsons and Harkins (2002) discovered that hydrocyclones
was successful in trapping particles in the 50 to 100 μm size range. The
drawback to this method, however, is the difficulty in separating small aquatic
organisms that have similar density to sea water using centrifugation.
2.3.2 Biocides
According to Kazumi (2007), the efficient use of biocides in the removal of HAOP
from ballast water should satisfy both the need for effectiveness in inactivating the
potential HAOP and degradability or removability of any form of residual effect of
the biocides in the discharged water. The following chemicals; chlorine, chlorine
dioxide, hydrogen peroxide, glutaraldehyde, menadione, peracetic acid, phenol, and
32
cationic surfactants (such as C16-alkyltrimethylammonium chloride) according to
the author, showed a satisfactory result against a wide range of organisms in both
marine and freshwater environments. Menadione and phenol are the only biocides
not used to disinfect water systems.
Most oxidizing chemicals used in waste water treatment are effective in destroying
the cell membranes and other organic structures of the organisms they come in
contact with, while non-oxidising biocides, on the other hand, are reported by
Dobroski et al. (2009) to work like pesticides by interfering with neural, reproductive
or metabolic processes of organisms. Biocides (e.g., chlorine dioxide, ozone) used to
treat drinking water according to Philips (2006), can effectively kill microorganisms.
Effectiveness of some biocides like hydrogen peroxide, chlorine, chlorine dioxide,
ozone, gluteraldehyde, copper/silver ion systems on some organisms in the Marine
Target Species List (MTSL) were tested and reported by Rigby et al. (1998). The
outcomes were generally satisfactory, although high concentrations were required in
some of the cases which could pose significant safety, environmental or operational
problems.
Laboratory studies aimed at ballast water treatment by Rigby et al. (1998 & 1999),
Kazumi (2007), Hillman et al. (2004), and Dobroski et al. (2009) have shown various
biocides to be effective against a wide taxonomic range, though none were 100 %
effective in terms of targeted organisms.
For the most part, biocidal effectiveness was reported by Rigby et al. (1998) as LC90,
(lethal concentration required to kill 90 % of the population of test organisms), or
LD50 (lethal dose required to kill 50 % of the population of test organisms) after a set
period of time of usually 24 hours. The findings above cannot be easily evaluated on
the basis of the IMO discharge standard which is based on organism size and number
discharged per quantity of water: however, the effectiveness of the treatment is not in
doubt. For the purpose of this research work (onshore treatment), the finding is very
important. Rigby et al. (1998) concluded that the findings shall provide a basis from
which future efforts on biocidal effectiveness in the context of IMO regulations can
be carried out.
33
Furthermore, for reliable and effective treatment of ballast water with biocides,
Kazumi (2007) concludes that biocide dose vs. contact times must be known. CT
values are used in the treatment of potable water, where C is the residual disinfectant
concentration in mg l-1
and T is the time (in minutes) that water is in contact with the
disinfectant to meet microbial disinfection profiling and benchmarking provisions of
the CT tables of the water boards (Kazumi, 2007). Mortality, therefore, increases
with increased value of CT.
Chick’s Law is the underlying principle whereby municipal water is reliably and
effectively disinfected. Therefore, to inactivate unwanted organisms transported by
ballast water and to meet the requirements of IMO regulation, it is envisioned by
Kazumi (2007) that CT values and tables could be established for use in this
application.
A). Oxidizing Biocides:
(i) Chlorine dioxide: Chlorine dioxide at a concentration of 3 parts per million
according to Hillman et al. (2004) was 97% effective in reducing the hatching rate of
cysts after 40 hours.
(ii) Sodium Hypochlorite: Kazumi (2007) reported that sodium hypochlorite was
effective in freshwater with a 24 h LC90 value of 5 mg l–1
against the oligochaete,
Lumbricus variegatus and the cladoceran, Daphnia magna. Whereas against adult
zebra mussels the author reported that hypochlorite was not as effective with a 24 h
LC90 value of 130 mg l–1
. The ability of adult mussels to close their shell valves
when exposed to toxic substances could account for the low efficacy of the chemical
on the organism.
(iii) Hydrogen Peroxide: Kuzirian, Terry, Bechtel and James (2001) found that 1, 3
and 10ppm of hydrogen peroxide were successful against a wide spectrum of marine
plankton. Depending on the concentration of H2O2, the time for 100 % mortality
ranged between 5 to 35 min according to Kazumi (2007). Gollasch (1997) found that
1% H2O2 was effective against the cysts of phytoplankton as e.g. Gymnodinium
catenatum.
34
(iv) Ozone: Laboratory studies with ozone (O3) by Kazumi (2007) showed that
dosages of 9 mgl
–1
(at pH 7) and 14 mgl–1
(at pH 8.2) and 24 h contact time in
seawater was successful against Bacillus subtilis spores, an indicator organism used
for biocidally resistant spore-forming organisms in ballast water. In a similar
experiment the author stated that for a similar success rate against marine
dinoflagellate cysts, Amphidinium sp., ozone doses of 5 to 11 mg l–1
, and 6 h of
residual contact were needed.
Larger scale studies reported by Gollasch (1997) demonstrated that ozone gas
diffused into a ballast tank for 5 and 10 h inactivated up to 99.99 % of the culturable
bacteria, > 99 % for dinoflagellates and 96 % for zooplankton. Kazumi (2007)
reported that extended contact times of up to a couple of days were needed for
effective treatment of organisms in seawater with ozone. A study by Prince William
Regional Citizens’ Advisory Council (PWSRCAC, 2005) reported that between 5
to10 hours of ballast water ozonation resulted in 71-99% mortality of most marine
phytoplankton, zooplankton, and bacteria. Gollasch (1997) on the other hand had a
more rapid ballast water ozonation outcome than PWSRCAC (2005) at a dosage of
1-2 mg per liter with contact times of just 5 to 10 minutes. The results by Sassi,
Viitasalo, Rytkonen, and Leppakoski (2005) showed mortality rates of 96.10% for
copepods, 98.10% for copepod nauplii and 99.10% for rotifers with ozone dosage of
17 mg/l. At a dosage of 7 mg/l, according to the authors, the results were 95.10% for
copepods, 96.10% for copepod nauplii, 97.10% for rotifers and 99.10% for barnacle
nauplii.
B). Non-Oxidizing Biocides:
(i). Glutaraldehyde: Kuzirian et al. (2001) reported glutaraldehyde to have a variable
biocidal effectiveness against oligochaetes, cladocerans and amphipods. In another
experiment, the researchers reported 90% mortality of organisms when treated with
at least 500 mg l-1
of glutaraldehyde for 24 hours.
(ii) Menadione (vitamin k3): Reports from laboratory studies by Sano, Maupili,
Krueger, Garcia, Gossiaux, Phillips and Landrum (2004) have shown menadione to
35
be effective against a freshwater amphipod, Hyalella azteca and an oligochaete,
Lumbriculus variegates, with an estimated 24 h LC90 for these organisms at less than
2.5 mg l-1
. Kazumi (2007) also reported that menadione was also toxic to eggs of
Brachionus plicatilis (a marine rotifer), Daphnia mendotae (a freshwater
cladoceran), and Artemia sp. (a marine brine shrimp). Daphnia eggs were found by
the researchers to be the least sensitive, with a 24 h LD90 of 8.7mg l-1
.
A laboratory efficacy of 24 h LD50 in the range of 0.11 – 7.62 mg l-1 were reported by
Kazumi (2007) when tests were performed on some ballast water surrogate
organisms from different trophic levels (bacteria, dinoflagellates, green algae, and
larvae of crustaceans and mollusks) using menadione nicotinamide bisulphite (MNB)
which is a highly water soluble and extremely photodegradable chemical, with a
half-life of < 6 h.
(iii) A combination of Peracetic acid and Hydrogen peroxide has been reported by
Kazumi (2007) to be effective in the killing marine organisms. The main bioreactive
component in the combination is peroxyacetic acid (PAA), with hydrogen peroxide
(H2O2) as the secondary active ingredient that acts as a weak biocide for bacteria.
C). Ultraviolet (UV) Light:
UV light is effective against pathogens (Waite & Kazumi, 2001a), it is low
maintenance, and no residuals are formed as in chemical biocide applications. Its
effectiveness is lowered by turbidity and colour (Hillman, et al., 2004; Chase, et al.,
2000), so ballast water may need to be filtered before treatment. It is currently used
in hospitals, homeless shelters, and prisons to kill microorganisms and prevent the
spread of disease (Hillman et al., 2004). Ultraviolet treatment works to achieve
sterilization by exposing target organisms to ultraviolet light (UV) energy waves
(California Environmental Protection Agency, 2002). The technology inactivates
microorganisms by disrupting the DNA within cells, thereby prohibiting their
replication (Dobroski et al., 2009; Kuzirian et al., 2007). Between 97-99%
inactivation was achieved when different bacteria and viruses were irradiated with
20-MW/cm2
/sec dose (California Environmental Protection Agency, 2002).
36
2.3.3 Other Treatment Methods
(a) Deoxygenation: Deoxygenation involves the displacement of oxygen with inert
gas such as nitrogen or carbon dioxide. Most aquatic organisms require oxygen for
survival: therefore, any treatment method that can deprive the organisms of oxygen
might suffice as a good treatment method. Deoxygenation as a treatment method
basically uses oxygen deprivation to kill HAOP contained in ballast water. Current
research by PWSRCAC (2005) revealed that lowering the level of oxygen to less
than 3 milligrams per liter will result in effective kill rates for HAOP.
In the laboratory, as reported by Kazumi (2007), researchers exposed three invasive
invertebrates (Ficopomatus enigmaticus, a polychaete;Carcinus maenas, the
European green shore crab; and Dreissena polymorpha, the zebra mussel) to hypoxic
conditions (O2 levels of 0.8 mg l-1
) for 2 to 3 days, and observed that there was 20 %
survival of the polychaete and the zebra mussel.
Deoxygenation, while mainly a physical process also has a chemical component. The
component is the addition of carbon dioxide which produces a reduction in pH that
enhances killing efficacy (Dobroski, et al., 2009).
According to Hillman et al. (2004) deoxygenation or hypoxia could remove many
organisms of interest, and may also stimulate corrosive anaerobes, which is an
important disadvantage of this method. Also Kazumi (2007) reported that
deoxygenation kills metazoans (i.e., all animals except protozoans and sponges), but
not bacteria or protists. These outcomes were also supported by the outcome of
research by Tamburri, Wasson, and Matsuda (2001).
To prove that aquatic organisms are sensitive to oxygen levels, the experiment by
Tamburri et al. (2001) explored the effect of nitrogen ballast water treatment as a
deterrent to non-native species introductions. They examined the oxygen tolerance of
larvae from three known nuisance invasive species now found in U.S. waters—an
Australian tubeworm, European green crab, and European zebra mussel. The low
oxygen condition created was toxic to all of the larvae after only two to three days.
(b) Thermal treatment: Rigby et al. (1999) based on microscopic observation of
heated ballasted water concluded that temperatures of 38 °C for several days could
37
kill all zooplankton and a greater percentage of phytoplankton. Gollasch (1997)
reported that temperatures of 40 to 45oC on the Vessel, IRON WHYALLA
effectively killed both phytoplankton and zooplankton and exposure to temperatures
of 36 to 38oC over a period of 2 to 6 hours was sufficient to kill zebra mussels in
pipes.
Chase et al. (2000) in another study reported that temperatures between 35oC (95o
F)
and 45oC (113o
F) maintained for a long enough period of time is effective at killing
larger organisms, such as fish, but not as effective at killing microorganisms as
shown in Figure 2.1. The author also reported a study in Australia where most
organisms were destroyed as ship ballast water reached temperatures of close to 40oC
(104o
F).
(c) Advanced Oxidation Technologies: Tamburri et al. (2001) reported that when
dissolved hydroxyl concentration was 0.63 mg l-1
, the kill efficiencies of bacteria,
phytoplankton and protozoans reached 100 % within 2.67s.
2.3.4 Combination of Treatment Methods
With many treatment methods under investigation, researchers have not as yet
discovered any method that could singly achieve satisfactorily the IMO’s treatment
systems objectives of safety, environmental acceptability, technical feasibility,
practicability, and cost effectiveness. Some treatments may need to be accompanied
by another treatment that covers another category of organism.
Figure 2.1 shows the organism sizes covered by the various methods. The primary
treatment, as the first line of defence in the treatment system, first removes the larger
organisms and particles like zooplankton and turbidity. Afterwards, the water is
subjected to secondary treatment such as UV or biocidal treatments to remove
smaller organisms like bacteria and phytoplankton. Although BWE can remove
organisms of all classes, it is short of meeting the IMO Performance Standards
requirements.
In an experiment conducted with water from Biscayne Bay (FL), USA using either
hydrocyclone or filtration as a primary treatment stage, Waite and Kazumi (2001b)
reported that hydrocyclonic treatment was ineffective, while a 50μm screen removed
38
most of the zooplankton. Secondary treatment with UV showed an initial reduction
in the viable counts of microorganisms, but bacterial regrowth was observed after 18
hours.
In a study where hydrocyclone, screen and biocides were combined, Kazumi (2007)
reported that the treated water was found to comply with IMO performance standard.
These and other study results have given credence to the notion that no single
treatment system can satisfactorily achieve IMO’s performance standard, a
combination of treatment systems is therefore required.
Figure 2.1: Ballast Water Management Methods for specific Organism Sizes
(adopted from Chase et al., 2000).
In view of the fact that BWE as a stop gap option has failed to satisfactorily address
the issue of HAOP translocation via ballast water, ballast water treatment has
remained the only available viable option for the maritime industry. This chapter
reviewed literature on research related to ballast water management or treatment
which is the general theme of this study. There are a lot of research done and a lot
more in progress on treatment methods from which selection can be made for the
most appropriate method for the study area. The next chapter shall look at the
39
methodology deployed to collect and analyze both the samples and the data in this
study.

40
CHAPTER THREE
METHODOLOGY AND DATA COLLECTION
3.1 DESCRIPTION OF THE STUDY AREA
The study area is the Port Harcourt Harbour General Cargo Terminal and the Oil
Terminal (also known as Okrika Jetty). Both are located in the mangrove swamp
vegetation belt of Nigeria’s Niger-delta, along the Bonny estuary which drains into
the Gulf of Guinea in the Atlantic ocean (see Figure 3.1). The General Cargo
Terminal lies between latitude 4
o
46’17’’ and 4
o
45’33’’N and between longitude
7
o
00’21’’ and 7o
00’13’’E. The Terminal has a total of ten berthing spaces covering a
total length of 2.55km (1.59 miles), whereas the Okrika Oil Terminal lies between
4
o
45’11’’ and 4o
44’48’’N and between longitude 7o
00’10’’ and 7o
00’08’’E. It has a
total of 4 berthing spaces covering a total length of 0.57km.
Figure 3.1: Map of Nigeria, West Africa. Source: https://monkessays.com/write-my-essay/waado.org.
41
Figure 3.2: Map of the Niger-delta Region of Nigeria (left) and a zoomed Map of
the Study Area showing Sampling Stations; General Cargo Terminal (NP1 &
NP2) and Oil Terminal (OK1 & OK2), in Port Harcourt Harbour (encircled in
red) on the Bonny Estuary (right). Source: Google maps.
3.2 THE SCOPE OF THE STUDY
The data used for this study were collected by direct field measurements. The study
covered sampling of the surface water marine environment of Port Harcourt Harbour
(General Cargo Terminal and Okrika Oil Export Terminal). Each terminal had two
sampling locations; NP1 and NP2 for the General Cargo Terminal and OK1 and OK2
for the Oil Terminal (see Figure 3.2). The samples were subjected to taxonomic
laboratory analysis, and different classes of planktonic organisms were identified. As
a result, a more ideal treatment procedure was eventually proposed by this study for
Port Harcourt Harbour, based on the ballast water treatment research literature
reviewed in the course of this study.
3.3 SAMPLING LOCATION
The sampling locations for this research were situated at the Port Harcourt Harbour.
The Harbour has both a General Cargo Terminal consisting of ten (10) berths, and an
oil terminal consisting of four (4) terminals. The export terminals are centers of
42
contamination from other ports around the world as they are basically loading
terminals, where ballasted water is discharged in order to load cargo (petroleum
products). The General Cargo Terminals are basically import terminals where ballast
water is loaded from the port after cargo discharge, making them sources of
contamination for other ports.
On the basis of the expected difference in both biological and physicochemical
characteristics of different harbours around the world, it would be expected that the
treatment facilities in different regions of the world should have different treatment
processes. Treatment plant in a port in West Africa for example, should not be
expected to be exactly the same with that of a port in Sweden.
3.3.1 Sampling Stations
Four (4) sampling stations were established along the stretch of the study area (Port
Harcourt Harbour); two each at both the General Cargo Terminal and Okrika Oil
Terminal. The sampling locations were selected because they are situated in some of
the major import and export terminals along the Bonny estuary.
Port Harcourt Harbour
General Cargo Terminal:
Station I referred to as NP1 (Upstream) -Samples of the General Cargo Terminal
ambient surface water were collected at berth 8 in the following position;
4
o
46’12.20’’N, 7o
00’14.09’’E and at elevation of 3 meters above sea level.
Station II referred to as NP2 (Downstream) -Sample was collected at the General
Cargo Terminal at position 4
o
45’38.41’’N, 7o
00’16.04’’E and at elevation of 2
meters above sea level.
Okrika Oil Terminal
Station III referred to as OK1 (Upstream) -Sample of the Oil Terminal ambient water
was collected at the following position; 4o
45’03.29’’N, 7o
00’07.72’’E and at
elevation of 3 meters above sea level. This sampling was done further towards the
bank of the river. This accounts for the higher elevation above sea level in Station III
than Station II.
43
Station IV referred to as OK2 (Downstream) -Sample was collected at position
4
o
44’51.69’’N, 7o
00’08.43’’E and at elevation of 1meter above sea level.
Collection of port ambient surface water samples was carried out between 3rd
January 2012 and 6th January 2012. The harbour or ambient water samples were
collected using two methods; scooping the nets through the harbour water and also
by filtering collected harbour water through the nets. The net types used were 63µm
plankton net for phytoplankton and 100µm plankton net for zooplankton.
3.4 SAMPLE ANALYSIS
3.4.1 Methodology for Physicochemical Characterization of Study Area
The physical and chemical quality of water according to Swingle (1969) has a direct
effect on the quality and suitability for utility, productivity and distribution of aquatic
organisms. Oyewo and Don Pedro (2003) also reported that the toxicity of trace
heavy metals on estuarine organisms is controlled by the variability of water quality
and this determines the physical and chemical composition of the ecosystem. This
makes the study of the physical and chemical characteristics of the water in the study
area very essential to this research.
The physical and chemical parameters that have been studied in this research are;
temperature, hydrogen ion concentration (pH), electrical conductivity, salinity,
turbidity, and dissolved oxygen (DO). The methods described by APHA: Standard
Methods for the Examination of Water and Waste Water (1998) were employed
(APHA, 1998).
3.4.1.1 Temperature
The water temperature was measured in-situ in the field using mercury in glass
thermometers (0-50oC) graduated at 0-01oC intervals. The sensitive part of the
thermometer was immersed directly into the water and the instrument was allowed to
stabilize. At stability, the temperature value was read. Three instrument readings
were measured and the mean value of the three was calculated and recorded as the
surface water temperature for the station. The same procedure was repeated in all the
sampling stations.
44
3.4.1.2 pH levels
The water hydrogen ion concentration pH was measured in-situ directly in the field
using a multiple-parameter Horiba water checker (model U-10µ). The instrument
was first calibrated with the standard Horiba solution; the measurement for pH was
done as soon as possible by dipping the probe into the water. The switch button was
put on while the arrow key moved to pH command displaying the values. After the
value stabilized, the reading was taken. This was repeated three times and the
average recorded. The same was done for all sampling stations.
3.4.1.3 Electrical Conductivity
The electrical conductivity of the sample at the four stations was measured in-situ
instrumentally using the same Horiba multimeter. The same procedure was adopted
as in pH but the arrow key was positioned on electrical conductivity parameter.
When the instrument stabilization was completed, the value was taken and recorded
and then the calculation of the mean value was recorded.
3.4.1.4 Total Dissolved Solids (TDS)
The TDS for each sample at the four stations was calculated by multiplying the
electrical conductivity (EC) of each station sampled by a factor of 0.7 as the
conversion factor. Standard formula for TDS= 0.7 x EC.
3.4.1.5 Salinity
Salinity of the water sample from each of the three stations was determined similar to
that of electrical conductivity. The measurements were done in-situ in the field by
the use of the same instrument (Horiba). The instrument was rinsed properly several
times with distilled water at each station before measurement was taken; this was to
ensure accurate readings. The instrument was allowed to standardize for about 20
minutes before salinity values were taken, calculated and recorded.
3.4.1.6 Turbidity
Turbidity of the water in each of the sampled stations was carefully measured with
the multi-meter (Horiba) in-situ in the field, after the instrument had been
standardized with reagent and distilled water. It was then rinsed with the harbour
45
water sample of the station at which the sample was collected. The probe was dipped
directly into the water and allowed to stabilize at turbidity parameter before the value
was taken and recorded.
3.4.1.7 Dissolved Oxygen (DO)
Surface water samples for the measurement of dissolved oxygen (DO) were collected
and determined according to the modified Azide or Winkler’s method (APHA,
1998). A well labeled clean 70ml DO bottle initially rinsed with a water sample from
the station was dipped below the water surface and allowed to fill to overflow in
order to completely remove trapped air bubbles. In the bottle filled with the sample,
0.5ml manganous sulphate (Winkler-I) solution and fixed with 0.5ml alkali-iodide
azide reagent (Winkler-II) were added, stopper placed (excluding air bubbles) and
mixed with several inversions. The sample was allowed to stand for few minutes and
was packed in a cool box containing ice blocks for onward transportation to the
laboratory for further analysis.
Winkler titration methods were used to carry out the determination of DO
concentration as recommended by the standard methods for the examination of water
and wastewater 20th edition APHA-AWWA-WPC, Washington DC (APHA, 1998).
To the DO sample in the laboratory previously treated with Winkler I and II was
added 0.5ml concentration of H2SO4, stopper placed and mixed for complete
dissolution of precipitate.
A 50ml portion of the sample was placed in an Erlenmeyer flask, 5 drops of freshly
prepared starch solution were added and titrated with 0.025N Na2SO4 (Sodium
thiosulphate) solution. The titration was continued to the first disappearance of the
blue colour. DO in mg/l was calculated using:
V×N×8000
ml of sample
Where V is volume of sample in ml and N is normality of sodium thiosulphate
solution used in the titration.
A table summary of all the physicochemical results for the samples is found in
Appendix A.
46
3.4.2 Methodology for Biological Characterization of Study Area
3.4.2.1 Phytoplankton
A plankton net (mesh aperture = 63 µm) was used for the quantitative (10 liters)
filter-sampling of the phytoplankton. The phytoplanktons on the sides of the net
were washed down into the collection bottle with the water from the outside.
Samples were put in a 250 ml labeled container and preserved with 5% neutral
formalin and kept in the dark. The samples were later filtered through a 0.45μm
membrane filter paper (with a vacuum of less than 0.5 atm) and preserved with 70%
ethanol in the laboratory. Volume was made up to 100 ml. The size of the subsample was 1/100.
3.4.2.2 Zooplankton
A simple conical filter-net (mesh aperture = 100 µm) was used for the quantitative
(10 liters) filter – sampling of the plankton. The zooplankton on the sides of the net
was also washed down into the collection bottle. Samples were put into a 250 ml
labeled container and preserved with 5% ethanol and kept in the dark. In the
laboratory the samples were concentrated immediately and preserved with 70%
ethanol (5% glycerin also added) and volume made up to 100ml. The size of the subsample was 1/100 and the estimated volume sampled per station was 7 m
3
.
The plankton (zooplankton and phytoplankton) population was enumerated using a
counting chamber {Sedgwick – Rafter (S-R) counting cell} which limits the volume
and area for the ready calculation of population densities (Verma & Agarwal, 2006;
APHA, AWWA, & WPCF, 1976; Newell & Newell, 1977). The tally system was
also adopted in this method. After counting, the number of cell per ml was then
multiplied by a correction factor so as to adjust for dilution of the sample. The
organisms were identified using standard bench references and reported as number of
individuals per ml (APHA, AWWA, & WPCF, 1976). The individual organisms
were identified with the aid of a Ziess binocular microscope at x40/100x, a standard
bench reference (Newell & Newell, 1977; APHA, AWWA, & WPCF, 1976) and
CD–ROM from the Intergovernmental Oceanographic Commission of U.N.E.S.C.O.
47
A table summary of the plankton taxonomic count results for all the samples can be
found in Appendices B and C.
3.5 DATA ANALYSIS
The relative dominance (RDO) of species was calculated using Excel Descriptive
Statistical Tools (see Appendices B & C). Densities of the abundant species were
analyzed for each of the sampled stations as follows:
Density= Total number of species ………………… (1)
Area of sampling unit
3.5.1 Statistical Analysis
All statistical analyses in this study were performed using GraphPad Instat® version
3.10 statistical software created July 10th 2009 (see Appendix E). Where necessary,
group variances were tested to assure homogeneity (Bartlett’s test) and the residual
were examined for normality using the Kolmogorov-Smirnov test (Motulsky, 2007;
Humphrey, 2008; see also Appendix E). Plankton density was heterogenous across
factor levels. In an effort to normalize and equalize the variances and enhance the
power of the parametric statistical tests, plankton densities were reciprocal (1/x)
transformed and in other cases log (log x) transformed prior to statistical analysis of
sampling stations relationship. In this case the skewness of the data was reduced, but
did not always satisfactorily homogenize the variances.
The important factors of interest in this study are the sampling stations which are
located in the General Cargo Terminal (NP1 and NP2) and the Oil Terminal (OK1
and OK2). The terminals could not be sampled across the predominant seasons in
Nigeria, i.e. dry and rainy season. Samples were collected during only one season;
dry season, due to time constraints.
Regression and correlation analysis and one-way Analysis Of Variance (ANOVA)
with Tukey’s posttest were performed using GraphPad Instat® version 3.10 for
Windows, GraphPad Software, San Diego California, USA, www.graphpad.com.
One-way ANOVA’s were used to test for differences in plankton densities as a
function of water temperature, pH, TDS, DO, electrical conductivity, turbidity and
salinity between sampling stations. It was assumed that an effect of any test was
48
significant using an a priori α level of 0.05. If ANOVA models proved to be
significant, unplanned multiple comparisons (Tukey test) were used to distinguish
group differences (Motulsky, 2007; Humphrey, 2008; Chiplonkar & Rao, 2007).
The next chapter shall consider a review and statistical analysis of the data obtained
from the field study to see how the identified characteristics of the study area interact
with each other to give an overall characteristic of the study area (harbour) and hence
determine the appropriate treatment system.

49

CHAPTER FOUR
ANALYTICAL REVIEW OF FIELD DATA
Eight samples were collected from Port Harcourt Harbourr surface water, four each
from the General Cargo Terminal and Okrika Oil Terminal. All water samples
collected were filtered through 63µm plankton net for phytoplankton and 100µm
plankton net for zooplankton.
4.1 PHYSICOCHEMICAL PROPERTIES OF STUDY AREA
A one sample t-test to determine the mean, the standard error of mean (SEM) and
the 95% confidence interval (CI) of the physicochemical parameters of sampled
stations was performed using GraphPad Instat 3 for Windows, GraphPad Software,
San Diego California, USA, www.graphpad.com (see Appendix E). The following is
the outcome of the one sample t-test:
4.1.1 Temperature (
oC)
On station by station, spatial water temperature had maximum value at NP2
(29.200±0.041
oC) while lowest was at OK2 (29.000±0.041
oC). Confidence interval
ranges between 28.970±0.041 oC and 29.230±0.041 oC.
4.1.2 pH level
The pH of sampled water was slightly alkaline between 7.510 and 7.730 across the
stations (Appendix A). The highest value (7.730) was recorded at NP2, while the
lowest pH value (7.510) was in NP1. The mean pH value was 7.6275 and the 95%
confidence interval recorded ranged between 7.771±0.045 and 7.484 ±0.045.
4.1.3 Electrical Conductivity (µscm-1
)
Values observed ranged between 33600 µscm-1
and 34900 µscm-1
in NP1 and OK2
respectively. The conductivity values confidence interval recorded varied from
50
33169±324.04 µscm-1
to 35231±324.04 µscm-1
across the stations thus,
characterizing the water as brackish (Appendix A).
4.1.4 Turbidity (Natural Turbidity Units (NTU))
The range of turbidity was between 1.00 and 3.00 NTU (Appendix A) with
confidence interval varying between 0.1629±0.5774 to 3.837±0.5774 NTU across the
stations (Appendix A).
4.1.5 Salinity (PSU)
It was observed that the highest salinity value was obtained at OK2
(22.100±0.2213psu) and the lowest at NP1 (21.200±0.2213psu). The confidence
interval was between 20.921±0.221 and 22.329±0.221psu.
4.1.6 Dissolved Oxygen (mg/l)
The results of dissolved oxygen values are shown in Appendix A. The values ranged
between 6.600mg/l and 7.700mg/l. The lowest values were recorded at NP2 while
the highest values were observed at both OK1 and OK2. The Confidence Interval of
the dissolved oxygen was between 6.208±0.3038mg/l and 8.142±0.3038mg/l across
the stations (Appendix A).
4.1.7 Total Dissolved Solids (mg/l)
The result of TDS has 23520mg/l at NP1 as the lowest and 24430 mg/l at OK2 as the
highest. The mean was 23940mg/l: the lower 95% confidence limit was at
23218±226.83 and the upper 95% confidence limit was at 24662±226.83 across the
stations.
As determinants of the quality and suitability for utility, productivity and distribution
of aquatic organisms, the physical and chemical characteristics of the Port Harcourt
Harbour water as established by the results above and from the literature studied in
Chapter two have characterized the harbour water as brackish (with range of
salinity=21.20-22.10psu, conductivity=33600-34900µscm-1
and TDS=23520-
24430mg/l); slightly alkaline (with range of pH=7.51-7.73); and rich in nutrients or
rich in planktons (with range of temperature=29.00-29.20oC),
51
4.2 BIOLOGICAL CHARACTERISTICS OF STUDY AREA WATER
SAMPLES
4.2.1 Composition, Distribution and Relative Dominance of Plankton
A total of 29 species were identified, 15 were zooplanktons and 14 were
phytoplankton. Quantitative analysis of all water samples revealed that the subclass
calanoid copepod numerically dominated the zooplankton community (see Figure 4.1
and Appendix C).
Figure 4.1 Relative Zooplankton Density in Sample.
The subclass calanoid copepod represented 89.4% of the entire zooplankton
communities sampled; cyclopoda copepod 4.6% and total crustacean larva were
relatively numerically rare with 6% of observed taxa. Paracalanus pygmaeus and
Calanus finmarchicus with numerical abundance of 34.3% and 20.1% respectively
and both belonging to the subclass calanoid copepode are the two most abundant
zooplankton species sampled from all the stations in terms of numerical abundance,
relative dominance and density (see Appendix C).
Based on relative abundance, relative dominance and density, the subclass centricae,
predominates in the phytoplankton community with 34.0%, with Cosinodiscus
lineatus as the most numerically abundant species in the subclass (see Appendix B
and Figure 4.2). The subclass pennatae makes up 32.3%, desmidiaceae 18.1% and
52
harmful dinoflagellates make up the remaining 15.6% of the total phytoplankton
sampled in the four stations (Figure 4.2).
On a species bases, the harmful dinoflagellates cyst, Alexandrium minutum
responsible for red tides which cause paralytic shell fish poisoning (PSP) is the most
numerically abundant phytoplankton species sampled (see Appendix B).
Figure 4.2 Relative Phytoplankton Density in Sample.
4.2.2 Biological Differences
Differences in relative plankton abundance existed between sampling stations. Oneway ANOVA’s were used to test for the differences in plankton densities between
the sampling stations OK1, OK2, NP1 and NP2. Since ANOVA assumes that
samples are drawn from populations that are Gaussian and with equal SDs, to
achieve a Gaussian distribution species density data were, therefore, in some cases
either reciprocal transformed (1/x) or log transformed (log x), where x is number of
organisms/ml. On an a priori α level of 0.05, any test is assumed to be significant.
4.2.2.1 Difference in Phytoplankton Abundance between Stations.
A very significant difference exists between the phytoplankton densities of the
stations sampled (Figure 4.3; ANOVA, Fcalc=6.650; df= 3,52; p=0.0007; see also
Appendix E). ANOVA always assumes that the data are sampled from populations
with identical standard deviation (SD). This assumption was tested using the method
53
of Bartlett. Bartlett’s test suggests that the differences among the SDs is very
significant (Bartlett’s test p=0.0110).
Mean and Standard Deviation
Column
A B C D
0.01
0.009
0.008
0.008
0.007
0.006
0.006
0.005
0.004
0.004
0.003
0.003
0.002
0.001
0.001
0
Figure 4.3: Summary of Mean and SD of Phytoplankton Density in General
Cargo Terminal (NP 1 & NP 2) and Oil Terminal (OK 1 & OK 2) of Port
Harcourt Harbour.
Using Tukey-Kramer Multiple Comparisons Test, significantly higher phytoplankton
densities (p<0.01) were observed in the sample from OK2 (downstream) than in
samples from both NP1 and NP2 (upstream of OK2) (see Figure 4.3 and Appendix
E). This phenomenon could be as a consequence of nutrient enrichment of the water
or acquired mineral constituents in dissolved form as dissolved salts in solution from
high surface runoff, flooding, municipal and industrial effluents and agricultural
activities downstream between OK1 and OK2. A lot of the domestic and industrial
effluents around that precinct are discharged into the main stream of the estuary
somewhere between OK1 and OK2. This conclusion is also supported by the positive
correlation of phytoplankton density with salinity, conductivity and TDS which will
be discussed next.
The relationship between phytoplankton density (no of org/ml) and salinity (psu) is
very significant. A strong positive correlation exists between density and salinity
(Figure 4.4; regression analysis, r2
= 0.9034, df=3, p= 0.0495). Conductivity and total
dissolved solids (TDS) both also have a positive correlation with organism density
54
(log (mg/l)) (linear regression, r2
= 0.9196, p= 0.0411). This means that salinity,
conductivity and TDS are all individual determinants of phytoplankton density in the
sampling stations (p<0.05) with organism density increasing with an increase in the
value of each parameter. It therefore means that as we move seaward away from the
harbour, phytoplankton density should be expected to increase, since from the data
and logically as expected, salinity, conductivity and TDS should increase seaward,
which also agrees with the Tukey-Kramer’s test result (see Appendix E).
21.217 21.258 21.299 21.34 21.381 21.422 21.463 21.504 21.545 21.586 21.627 21.668 21.709 21.75 21.791 21.832 21.873 21.914 21.955 21.996 22.036 22.077
4
Figure 4.4: Total Phytoplankton Density log(mg/l) as a function of Salinity.
Linear regression analysis shows that the relationship between the density of
phytoplankton and DO is not quite significant (p=0.0555). The other measured
physicochemical parameters; temperature, pH, and turbidity do not show any
significant relationship with phytoplankton density (p>0.05).
4.2.2.2 Difference in Zooplankton Abundance between Stations.
There were no significant differences between densities of zooplankton in the
samples from all the stations (Figure 4.5; ANOVA, Fcalc= 0.4094, df=3,56, p>0.05;
see also Appendix E).
No statistically significant relationship was established also between zooplankton
densities and all the measured physicochemical parameters (temperature, dissolved
oxygen, TDS, conductivity, pH and turbidity) when they were subjected to the
correlation test (Figure 4.6; p>0.05).
55
Mean and Standard Deviation
Column
A B C D
0.008
0.007
0.006
0.006
0.005
0.004
0.004
0.003
0.003
0.002
0.001
0.001
0
Figure 4.5: Summary of Mean and SD of Zooplankton Density in General
Cargo Terminal (NP 1 & NP 2) and Oil Terminal (OK 1 & OK 2) of Port
Harcourt Harbour.
It therefore means that none of these physicochemical parameters is a factor in
determining zooplankton density in the sampling stations.
21.217 21.258 21.299 21.34 21.381 21.422 21.463 21.504 21.545 21.586 21.627 21.668 21.709 21.75 21.791 21.832 21.873 21.914 21.955 21.996 22.036 22.077
45,000
40,000
35,000
30,000
25,000
20,000
15,000
10,000
5,000
0
-5,000
-10,000
Figure 4.6: Total Zooplankton Density (mg/l) as a function of Salinity.
The study of the physical and chemical characteristics of the sampling stations and
how they influence the biological characteristics (plankton densities) of the stations
was the main objective of this chapter. From the physicochemical results, the study
56
area water is characterized based on observed salinity and electrical conductivity
(EC) as brackish (see 2.1.3 & 2.1.4), slightly alkaline based on the observed pH (see
2.1.2) and based on the temperature (see 2.1.1) as supporting an abundance of
aquatic organisms, which is predominated by the zooplankton taxa; calanoid copepod
and phytoplankton taxa; centricae, pennatae, desmidiaceae and harmful
dinoflagellates.
The study of these characteristics is not necessary unless the knowledge acquired can
aid in achieving the main objective of this study, which is to propose a unique
treatment system that best suits the established characteristics of the study area,
which is Port Harcourt Harbour in Nigeria and any port with similar environmental
characteristics.
The next chapter shall discuss the different ballast water treatment options, the
advantages of the proposed system over the traditional systems, how to manage the
risk of HAOP introduction from the host harbour and the responsibilities of States to
put in place a management procedure to minimise the potential risk of HAOP
introduction from their ports and how the knowledge of the physical, chemical and
biological characteristics of the study area is a necessary tool in determining the
uniqueness or specificity of the treatment system for the harbour.
57

CHAPTER FIVE
DISCUSSION
5.1 ONSHORE VERSUS SHIPBOARD TREATMENT SYSTEMS
The goal of every ballast water management programme is to control the spread of
HAOP from one region of the world to another. BWE (Regulation D-1) as a
management method has been unable to satisfactorily minimise species introduction
and transfer. Various treatment methods were therefore, introduced as alternatives
(Lafontaine, Despatie & Wiley, 2008; NRC, 1996). The performance standard
(Regulation D-2) as a management procedure for ballast water management has a
primary target of reduction of taxa densities in transported ballast. Total annihilation
of HAOP is not economically feasible, but according to NRC (1996) implementing a
system of ballast water management and controls reduces the probability of HAOP
introduction. Four treatment methods that have the potential of satisfying IMO’s
criteria for safety, environmental acceptability, technical feasibility, practicability,
and cost effectiveness while achieving the set goal of organism density reduction
were identified by NRC (1996). These treatment methods are: filtration, biocides,
heat and electrical pulse/pulse plasma system. Out of these four methods, the first
three are the most feasible and practicable for Port Harcourt Harbour considering the
harbour’s physical, chemical and biological characteristics identified by this study as
well as the financial and technical constraints of such a project in a developing
economy as Nigeria.
Treatment of ballast water can be carried out either onboard a ship or onshore in a
port. Figure 5.1 shows three types of ballast water treatment options; pre-loading,
shipboard and post-loading treatment systems. Shipboard and post-loading are
already in use around the world by ships and some harbours respectively. Shipboard
58
treatment is a ballast water treatment system (BWTS) where the treatment equipment
and procedure are wholly or partially situated onboard the ship.
The requirements of Regulation D-1 (ballast water exchange) and D-2 (performance
standards) in the BWM convention were meant to be strictly addressed onboard
ships. The entire convention according to Donner (2010a) has placed all operational
obligations for ballast water management on the ship rather than the ports, a situation
he referred to as “the solution of least resistance”.
Figure 5.1: Ballast Water Treatment Options: Onshore (proposed and existing)
and Shipboard Treatment Systems.
There is no mention anywhere in the convention of onshore treatment except onshore
reception facilities for sediments in Article 5. In fairness to the convention however,
there are provisions in Regulation B-3.7 and Article 4.2 for alternative ballast water
management methods and permission for parties to develop programmes for Ballast
Water Management in their ports and waters that promote the attainment of the
objectives of the convention. This is an obvious authorization by the IMO for
researchers to think outside the box, to explore and design management methods not
necessarily confined to shipboard. To encourage this, an exemption from regulation
D-2 for five years was given in regulation D-4 for ships participating in programmes
to develop prototype ballast water technologies.
Onshore treatment is a BWTS where the treatment equipment and procedures are
wholly or partially situated onshore in the harbour. The system is considered by this
59
study to have the capacity to satisfactorily meet IMO’s requirements in Regulation
D-2 as well as the criteria for safety, environmental acceptability, technical
feasibility, practicability, and cost effectiveness, and there are a number of reasons to
support this assertion. Personnel in the treatment facility, for example, are employed
by the port authority and not shipping companies, reducing financial pressures on
shipping companies. The treatment system is under the control of the port authority,
which allows for better control of both the treatment system and the training of the
operators. The relative spatial advantage a harbour has over a ship allows for the
application of more comprehensive treatment steps in a harbour than on a ship.
Figure 5.1 shows two of the onshore treatment options (pre-loading and postloading) both having more treatment steps or hazard barriers than the shipboard
treatment model. Also there is the advantage of greater storage availability for water
and chemicals in a harbour than onboard a ship.
The requirement for safety of the crew is also guaranteed by the onshore treatment
system as no ship crew is involved in the operation of the system because it is
operated onshore by trained port authority operators or approved contractors. Donner
(2010a) mentioned improved operational expertise as one of the advantages of shore
treatment over shipboard treatment. The number of operators will be adequate and
will receive training to be proficient in operating the treatment facility as their core
job function unlike in the case of a ship where that function is just one of the many
functions handled by a few crew members. According to Donner (2010a), the crew
will lack expertise in the optimal use of the facility if it is onboard a ship. Regulation
B-6 of the convention requires officers and crew on duty to be familiar with the
ship’s BWM plan, but that will not be likely especially in an industry like shipping
where there is a multicultural mix on board most ships and some crew members
might not be able to understand clearly the safety procedures associated with, for
example, the use of hazardous materials, if they are written in another language.
Also, mobility of labour is a tradition in the shipping industry. Ship’s crews are
always on a constant move to different ships or companies, and different ships have
different treatment equipment from perhaps different suppliers and therefore
60
different management plans. This however, is not the case for onshore treatment,
where there exists one treatment facility, one management plan, operated by the
same personnel (well trained) and serving many ships visiting the harbour affording
the facility the advantages of economies of scale, a fact also noted by Donner
(2010a).
The system will bring about a reduction in the quantum of paper work onboard ships
which has definitely resulted in additional workload on the ship’s crew; a factor
identified by researchers on the MARTOB project as contributory to fatigue and
unsafe conditions onboard ships (MARTOB, 2004). Most of the ballast water
management related paper work will now be the responsibility of port authorities and
not ships. Monitoring and verification of treatment results in onshore facility
according to Donner (2010b) could be a mere routine procedure, which is not the
case for shipboard where a more detailed and conscientious monitoring is required.
This is so because of the dubious “magic pipes” installed to by-pass the oily-water
separator of some ships discovered by some port state control inspectors monitoring
MARPOL regulation compliance of ships.
Donner (2010a) mentioned the financial commitment required to install the system as
one of the reasons states are often not interested in investing on the system. Looking
at the big picture, the system is quite affordable considering the fact that almost
every community in the world where a port is situated has a municipal water
treatment plant installed and operated by that community. Such communities should
be encouraged to install and operate BWTS’s for their harbours as well.
Alternatively, they could designate the responsibility to private entities and recover
their investments over time. The knowledge gained in municipal water treatment,
which is a very efficient water treatment technology, can be transferred into the
onshore ballast water treatment system.
Primary treatment (filtration) which should be a mandatory aspect of this system, can
filter back into the host environment organisms that could not go through the
filtration process, allowing them to be retained in their original environment, making
the system a more environmentally friendly system.
61
The facility can be self-sustaining, as the cost for maintenance could be paid by ships
or shipping companies in the form of environmental levies for such services rendered
by the ports. This levy should cover part of the cost for the installation and running
of the facility, this view is also corroborated by Donner (2010a).
Treatment methods requiring heat or biocides often require extended time frames for
optimal effectiveness. Onshore treatment has that time advantage over shipboard
treatment. Onshore treatment also provides the opportunity to easily plug any
available hole in the defense barriers or treatment steps in the system. This could
come in the form of an additional treatment stage or just an improvement in some
aspects of the treatment system (see Figure 5.1). This will lead to improvements in
the performance of the system, thus ensuring an effective BWTS.
Also, when for example, the IMO or a regional maritime organization sees a need to
introduce new regulations as a result of say a discovery of a new and better method
of treatment that will enhance the entire global ballast water treatment practice,
which will require retrofitting the existing treatment systems around the world or in a
region, it will comparatively be easier, less time consuming and cheaper to retrofit an
onshore treatment facility that can serve several ships in a harbour than retrofitting
each of the nearly 100, 000 global ship fleet. This view was also discussed
extensively and analyzed by Donner (2010b).
From the points stated so far, it is obvious that onshore ballast water management
practice has, potentially, the capacity for feasibility as well as the potential to ensure
that greater harm than it prevents does not result from its deployment in any harbour,
thus satisfying the requirement of Article 2.7 of the BWM convention (see Appendix
F for full text of Article).
5.2 PROPOSED TREATMENT SYSTEM
The conventional onshore treatment style discussed above is a post-loading treatment
system or a Next Port of Call (NPOC) solution. In this system, ballast water
treatment is carried out at the end of a ship’s voyage. The ship arrives at berth inballast to load cargo and discharges its ballast water content (deballast) into a port
62
reception facility where it is treated before it is discharged into the surrounding port
environment.
This study, however, is proposing a different kind of onshore treatment system
known as a harbour specific pre-loading treatment system, which is a Last Port of
Call (LPOC) solution (Figure 5.1a). It is a preventative treatment option and it allows
for the treatment of the harbour water of the port before it is uploaded as ballast
water into a ship. Guiding principle 2 of UNEP (1999) recognizes prevention as far
more cost effective and environmentally desirable than measures taken after
introduction of HAOP. Why a harbour specific treatment is needed is because the
conditions of the host port (referred to in this study as last port of call or LPOC) is
relatively stable and the biological, chemical and physical characteristics of the port
are well known to the port authority. The system, therefore, is aimed at removing
planktons that are characteristically native or resident in that port aquatic
environment before the water is loaded as ballast into the ballast water tank of the
ship. This system is quite novel, and certainly has some advantages over the postloading system.
The concern expressed by Pereira, Botter, Brinati and Trevis (2010), for example
about onshore treatment increasing ships turnaround time and congestion in ports as
a consequence of ballast water collection and storage processes, should be resolved
in the harbour specific pre-loading treatment style. Resident time constraints (i.e.
maximum time available to treat ballast water) imposed by voyage time will be
greatly cut down by this method, because by the time the ship arrives at the next port
of call (NPOC), there will be treated port water ready for loading as ballast water.
The possible insufficient capacity in many harbours to receive, store and treat ballast
water, which was noted as a potential disadvantage of the onshore treatment facility
by Donner (2010b) should not be an issue with the pre-loading onshore treatment
system, especially in a case where the ship’s ballast water has already been treated
from the last port of call (LPOC). Ships involved in pre-loading treatment do not
need to queue in port in order to discharge their ballast water tank contents into the
port’s reception facility; they can simply discharge it into the harbour environment
63
since their ballast water has already been treated from the last port of call (Figure
5.1a).
The system will further shorten the turnaround time of ships because most port state
control functions regarding ballast water management onboard ships might no longer
be necessary. The discharge of ballast water into surrounding water by ships either as
a result of an accident or for safety reasons will no longer present any danger to the
environment as the discharged water has already being treated. Also, the treated
ballast water can be used as a source of potable water for communities that have
problems with water. This of course will depend on the electrical conductivity of the
water (<1000µscm-1 means fresh water) and also on the level of treatment the water
is subjected to.
Port Harcourt Harbour shows a predominance of copepods in the zooplankton class
(see Figure 4.1 and Appendix C) and Alexandrium minutum as the most predominant
phytoplankton species (see Figure 4.2 and Appendix B). A unique combination of
three out of the four treatment methods identified by NRC (1996) as treatment
procedure for Port Harcourt Harbour can effectively remove these organisms from
the harbour. These methods are filtration, temperature and biocides in that order
(Figure 5.2).
The literature reviewed on ballast water treatment in chapter two showed the
following outcomes: Filtration using sand/anthracite as a filter was successful in
removing 89.4% and 94.5% of particles larger than 10µm and 15µm, respectively.
Using crumb rubber as a filter has 86.8% and 93.6% success for the same particle
sizes. Using biocides such as chlorine dioxide reduces hatching rate of cysts by 97%
after 40 hours. Ozone gas gave over 99% and 96% inactivation for dinoflagellates
and zooplanktons respectively after 5 to 10 hours. 96.10% and 98.10% mortality
were measured for copepods and copepod nauplii respectively when treated with
17mg/l of ozone. 1% ozone was also recorded to destroy phytoplankton cysts.
Heating to temperature of 38 °C for several days was discovered to kill all
zooplankton and a major portion of the phytoplankton. Filtration with 50µm material
as well as heating to temperature above 35oC could remove larger organisms (i.e.
64
zooplanktons). 96.10% of copepods and 99% of harmful dinoflagellates similar to
the ones found in Port Harcourt Harbour were destroyed by ozone.
Figure 5.2: Proposed Onshore Ballast Water Treatment System Stages for Port
Harcourt Harbour, Nigeria.
On the basis of this evidence, the most feasible, economical (i.e. affordable) and
effective BWTS for Port Harcourt Harbour therefore, should follow the order;
filtration, temperature and then biocides as shown in Figure 5.2. The Figure shows
propagule pressure (discussed in chapter one) reducing with every treatment
procedure in the proposed ballast water treatment system for Port Harcourt Harbour.
At the end of the treatment cycle, the water loaded as ballast unto a visiting ship in
the harbour will have a relatively reduced propagule pressure, which should be
sufficiently killed by the harsh conditions within a typical ballast water tank (Figure
5.2). The ship’s ballast water tank can be said to be a treatment system in its own
right, since studies have reported high levels of organism mortality inside the ballast
water tank. Humphrey (2008) reported significant reduction in plankton densities
within the ballast tank with longer voyages. Gollasch, Lenz, Dammer, and Andres
(2000) reported about 90% reduction within the first 4 days of a voyage. Wonham,
Walton, Ruiz, Frese, and Galil (2001) on the other hand reported a 99% reduction in
a ballast water tank after sixteen days. It is expected, therefore, that the residual
propagule pressure in the ballast water tank after the onshore (harbour) treatment
65
should be reduced to insignificance; a level where a release will not result in eventual
invasion. This is because the release of HAOP according to NRC (1996) constitutes
their inoculation and not necessarily their introduction.
5.3 HARBOUR RISK MANAGEMENT
Risk in a harbour as defined in chapter one has to do with the likelihood and
magnitude of an HAOP invasion. Risk management according to Orr (2003) is the
pragmatic decision-making process concerned with what to do about the risk (of an
HAOP invasion).
Based on the literature on ship mediated HAOP invasions, this study presumes there
is a risk in every ballast water translocation and discharge, until proven otherwise.
The precautionary approach set out in Principle 15 of the Rio Declaration and
Principle 1 in the UNEP guiding principles for the prevention, introduction and
mitigation of impacts of HAOP supports this presumption of risk. The precautionary
approach requires that preventative action be taken to prevent HAOP introduction
even when there is scientific uncertainty about the environmental risk posed by the
HAOP (United Nations, 1992b; UNEP, 1999). It is on the basis of this burden of
proof that the harbour specific onshore pre-loading BWTS is proposed by this study
to manage the potential risks of invasions by HAOP from the host or source port.
Orr (2003) mentioned entrainment potential, entry potential, colonization potential
and spread potential as the probability elements in HAOP establishment. To
effectively manage the risk of HAOP translocation from Port Harcourt Harbour (host
harbour) therefore, the first two elements should be checked by the proposed onshore
BWTS. The elements are thus;
1) Entrainment potential –this refers to the likelihood of any of the organisms found in
Port Harcourt Harbour slipping through the protective treatment barriers into the
ballast tank and
2) Entry potential- is the likelihood of entrained organisms surviving the voyage.
The probability of entrainment of HAOP from the harbour into the ballast tank of a
visiting ship should be the most essential element the harbour’s Ballast Water
Treatment System (BWTS) should curtail. The BWTS curtails this by introducing
66
barriers to the risk in the form of treatment methods (Figure 5.3). The second
element which is entry potential or the probability of entrained organisms surviving
the voyage will be determined by how effective the pre-loading onshore BWTS is.
Addressing the last two elements (colonization and spread potential) may not be
necessary as long as the first two elements have been curtailed by the BWTS at the
Last Port of Call (LPOC) or source port, which in the case of this study is Port
Harcourt Harbour.
The entrainment potential of HAOP will be greatly undermined by the three
treatment stages proposed by this study. Since invasibility is a game of numbers and
frequency, as explained earlier by the propagule pressure concept, the treatment
barrier arrangements (filtration, temperature and biocides) in Figure 5.3 will reduce
the possible number and density of organisms that can be uploaded into the ballast
tank, thereby greatly undermining the potential of HAOP entrainment.
Figure 5.3 shows the probability of HAOP establishment and the propagule pressure
of potential HAOP invasion reducing with every treatment stage. The probability of
taxon invasion depends on propagule pressure (Rejmanek, Richardson, Higgins,
Pitcairn & Grokopp, 2005).
Figure 5.3: Relationship between proposed treatment sequence for the Study
Area and Propagule Pressure /Probability of HAOP Invasion.
67
Each treatment stage is targeted at different classes of organisms as illustrated in
Figure 5.3. For example filtration is effective in removing all sizes of organism
especially larger organisms of size 10µm and above. The use of temperature is also
effective in removing larger organisms but not the smaller ones. The application of
chemicals (biocides) is effective in removing the smaller organisms that have
escaped the first two layers of treatment. By the end of the treatment procedure (in
Figure 5.3), the propagule pressure which is a major determinant of invasion risk and
the probability of establishment of the organisms would have been minimised to the
extent that the likelihood of the organisms that have survived the treatment process
and are eventually uploaded into the ballast tank surviving the voyage is crippled.
Research mentioned earlier in this chapter has shown 90% and 99% mortality for
organisms in ballast tanks on voyages of 4 and 16 days respectively. Following the
logic of the ‘tens’ rule, it therefore means that only 1/1000th of those that survive the
treatment and voyage will eventually get to the stage of becoming invasive or
pestiferous in a new environment, thus making the likelihood of invasion negligible.
5.4 STATE RESPONSIBILITY
Guiding principle four of the UNEP guiding principles for the prevention,
introduction and mitigation of impacts of HAOP, require States to “recognize the risk
that they may pose to other States as a potential source of alien invasive species
(Harmful Aquatic Organisms and Pathogens), and should take appropriate actions to
minimize that risk” (UNEP, 1999). This notion is also corroborated by both Article 3
of the Convention on Biological Diversity (United Nations, 1992a) and principle 2 of
the 1992 Rio Declaration on Environment and Development (United Nations,
1992b).
Figure 5.4 shows the transportation pathway and destination for HAOP entrained in
the ballast water tank of a hypothetical ship which has not undergone port specific
pre-loading ballast water treatment. The ship was involved in a trade between Port
Harcourt Harbour in Nigeria, located in the South Atlantic and Port of Halifax in
Canada and the Ports of Miami and Oswego both in the United States. These ports
are located in the North Atlantic, one of Port Harcourt Harbour’s leading trading
68
regions in the world. This scenario is from the hypothetical trade route mentioned
and illustrated in Figure 1.5 earlier in Chapter one of this study.
Figure 5.4: Hypothetical Shipping Trade Route between a port in Nigeria and
some ports in North America.
From the results of the surface water samples collected in this study (see Figure 4.1
and 4.2; see also Appendices B and C), 29 planktonic species were identified, 5
were nonindigenous to the Great Lakes, and 2 each were nonindigenous to Atlantic
and Pacific North America as shown in Table 1. Port Harcourt Harbour serving as a
donor port in this hypothetical case could be a potential source of HAOP to the
mentioned ports in North America with the harmful dinoflagellates, Alexandrium
minutum as the most predominant phytoplankton species sampled in the harbour and
also the following zooplankton species of copepod; Acartia clausi, Pseudocalanus
elongatus, Tortanus sp. and Oncaea sp. (a cyclopoida) which are non-indigenous to
the North American aquatic clime (Table 1). The contamination could hypothetically
be via any ship that has not undergone a ballast water management procedure such as
the pre-loading treatment. Many studies have already shown that BWE is not
sufficiently effective in stopping the HAOP menace.
69
Table 1: Planktons Identified as Non-indigenous to North America Sampled in
Port Harcourt Harbour.
ATLANTIC
N/AMERICA
GREAT
LAKES
PACIFIC
N/AMERICA
ZOOPLANKTON Acartia clausi Nonindigenous
Nonindigenous
Pseudocalanus
elongatus
Nonindigenous
Nonindigenous
Tortanus sp. Nonindigenous
Oncaea sp. Nonindigenous
PHYTOPLANKTON Alexandrium
minutum
Nonindigenous
Nonindigenous
Nonindigenous
Nigeria as a State party according to guiding principle four of UNEP (1999) is
required to take ‘appropriate actions to minimise that risk’ of contamination. The
proposed management procedure for Port Harcourt Harbour could serve as that
‘appropriate action’ to lower the risk of HAOP invasion from Port Harcourt Harbour
as illustrated in Figure 5.5.
Figure 5.5: Risk Impact/Probability Chart for Proposed BWTS.
70
The proposed treatment arrangement (filtration, temperature and biocides) as
illustrated in Figure 5.5 is shown to lower the risk of invasion further from high to
low risk by reducing the organism’s density and their probability of entrainment.
Conversely, Port Harcourt Harbour when serving as a receiver port could also be
contaminated by ships visiting from any of the ports in North America if they also do
not have a harbour specific onshore pre-loading treatment system or an ‘appropriate
action’ or a viable ballast water management process that is substantially equivalent
to an “ appropriate action”.
5.5 MANAGEMENT DECISION FLOW CHARTS
The decision as to the type of treatment system a port should have should ultimately
be the responsibility of the port authority. Risk analysis according to NRC (1996)
can be used as a strategic decision aid to help decision makers in the port authority in
choosing the appropriate treatment system for their port. Proper risk assessment of a
harbour cannot be carried out without a good and up to date scientific baseline
dataset of the harbour.
Guiding principle five of UNEP (1999) on Research and Monitoring, require States
to undertake research and monitoring of HAOP in order to address the problem.
Scientific baselines according to Andow (2005) are criteria used to set a presumption
of risk for alien introductions or harbour to harbour contamination (in the case of this
study). The basic scientific baseline information about the port should be on the
physical, chemical and biological characteristics of the port. For example, a slight
change in the study area which, as stated earlier, is located along the Bonny estuary
in Nigeria (Figure 3.2) was observed. On account of the physicochemical parameter
data obtained from this study (see Chapter four) and those reviewed from previous
research on the Bonny estuary in chapter two, there is an observed shift in some
physicochemical characteristics of the estuary. The average temperature,
conductivity and pH recorded during this study were observed to be higher than
those recorded along the estuary by researchers in 1998, 2003 and 2006. This
underscores the importance of continuous environmental monitoring of the harbour
to update the baseline information.
71
Figure 5.6: Port Authority’s (Port of call) Onshore Ballast Water Management
Decision Flowchart Model.
Figure 5.6 shows a proposed conceptual management decision flow chart model for
Port Harcourt Harbour which is also applicable to any port that has an onshore pre-
72
loading BWTS. The port authority decides the type of treatment system A to be
installed in the port that is based on the specific baseline information on the port. For
example, Figure 4.1 and 4.2 showed copepods and harmful dinoflagellates
predominance and Figure 4.6 shows a strong positive correlation between plankton
density and salinity, TDS and conductivity in the samples collected from Port
Harcourt Harbour (p<0.05).
This unique baseline information should guide the port authority in deciding whether
to go for a single treatment system C or a combination of systems B and what kind of
combination is appropriate for the harbour. In the case of this study the appropriate
decision, considering the Harbour’s unique physical, chemical and biological
characteristics as well as its financial capacity, is to go for a combination of
treatment methods (filtration, temperature and biocides) which is treatment system B
from the flow chart (Figure 5.6).
Figure 5.7 is a proposed onshore ballast water management decision flowchart model
for ships visiting Port Harcourt Harbour. If a ship arrives in the harbour in-ballast to
load cargo and she is from a port operating the pre-loading treatment system, from
the flow chart, the decision will be to discharge the treated ballasted water into the
harbour environment or to a potable water reception facility if it is available in the
harbour as illustrated in the flowchart. But where the ballast water is untreated, it is
discharged into a port reception facility for treatment before it is discharged into the
harbour environment or to a potable water reception facility if the treated water is
meant for human consumption or other domestic uses that need more stringent
treatment requirements. This is economically feasible only in cases where the water
is from a fresh water harbour which means having a conductivity of less than
100µscm-1
.
73
Figure 5.7: Ship’s Onshore Preloading Ballast Water Management Decision
Flowchart Model.

74

CHAPTER 6
CONCLUSION AND RECOMMENDATIONS
6.1 CONCLUSION
Risk reduction for Port Harcourt Harbour as stated earlier can be achieved through
filtration of harbour water, application of temperature of above 35oC to the water
being treated and the introduction of biocides (ozone is recommended by this study)
into the water. This was shown from literature to achieve an over 95% kill rate for
all identified planktons sampled in Port Harcourt Harbour in this study.
A harbour that possesses similar physicochemical characteristic with the study area
should be expected to harbour organisms with similar environmental tolerance and,
therefore, similar treatment systems can be applicable to both. Survivability of
marine organisms in any environment is determined by the suitability of that
environment to support the organisms. Suitability is a function of the physical,
chemical and biological (presence of predators, and competitors) characteristics of
that environment.
This proposal does not claim to have found the answers to the global menace of
HAOP, but rather it is suggesting another angle for consideration in tackling the
issue. The proposal has its inherent draw backs. The system does come with its own
unique need for retrofitting ships with special ducts to upload the treated ballast
water from the treatment plant and also some unique piping systems need to be
installed in the harbours, resulting in both ships and harbours incurring costs for new
infrastructure. The use of biocides in the system could leave some residual effect in
the water which portents greater harm to the environment than it may resolve
especially when proper dosage and disposal requirements are not followed. The
system might also not completely eliminate the menace of ballasted HAOP, because
75
safety requires that ballast water should be taken by ships in these cases; when the
ship needs to clear a bridge and when she needs to compensate for weight lost as a
result of fuel and water usage. It is considered, however, that ballast water taken at
sea to compensate for weight loss is not as species rich as coastal water taken from a
harbour. The system still has the potential to significantly reduce the menace,
perhaps much more than all other alternative systems before it, as all the other
possible alternatives have a number of inherent problems.
In conclusion, because only dry season samples and four stations were sampled,
conclusive generalizations about the characteristics of Port Harcourt Harbour are not
expected to be made based on this study’s outcome alone.
6.2 RECOMMENDATION
Further studies should be encouraged by the authorities in Nigeria to establish a more
detailed and reliable baseline data for Port Harcourt Harbour and the other harbours
in the country. This will enable researchers and the port authorities in the country to
make decisions regarding the design of a harbour treatment system more accurately.
It is also recommended that periodic studies of Port Harcourt Harbour’s marine
environment to identify environmental changes overtime should be carried out by the
Port Authority as part of the harbour risk analysis.
It is envisaged by this study that in the future, ballast water treatment could shift
from shipboard to onshore treatment in view of the potential for success in onshore
treatment. This study is, therefore, proposing to the IMO for consideration, the
adoption of an amendment to the BWM Convention to clearly include regulations on
onshore treatment systems because of the system’s potential to compliment or even
substitute for shipboard treatment.
This study recommends that strong trading partner nations should be encouraged to
cooperate amongst themselves (in line with Article 2.4 of BWM Convention on
cooperation) to have pre-loading treatment systems in their ports thereby exempting
their ships from the requirements of regulation D-2 until perhaps the year 2020
(according to regulation D-4.2 on exemption) within which period the proposal of the
co-operating parties to the IMO for amendment to the convention in accordance with
76
Article 19 would have been considered for global or regional applicability. Ships
coming from ports that do not have a pre-loading BWTS can still employ either
regulation D-1 or D-2, whichever is most applicable to their ships. But ships trading
between ports with treatment systems can continue to enjoy the inherent benefits the
system affords.
Finally, it is recommended also that further research to validate and establish the
applicability in the maritime industry of this hypothetical conclusion on the
effectiveness of the proposed treatment method should be undertaken by ballast
water management researchers.
.
77
REFERENCES:
ABS, American Bureau of Shipping, (2012). Ballast water treatment advisory. Retrieved
from website: https://monkessays.com/write-my-essay/eagle.org/eagleExternalPortalWEB/ShowProperty/BEA
Repository/References/ABS Advisories/BWTreatmentAdv.
Ademoroti, C.M.A. (1996). Standard method for water and effluents analysis. Foludex press
Ltd, Ibadan pp.22-23, 44-54, 111-112.
Akeh, L. E., Udoeka, E., Ediang, O. A., & Ediang, A. A. (2005). In G Pitcher
(Chair). Ballast water management and climate change in the coastline of nigeria:
Paranomic view. In Andersen,D.;Graneli,G.;Zhou,M.;Allen,J.I.;Burford,M.
(Eds.), HABs and Eutrophication (pp. 18-19). Retrieved from https://monkessays.com/write-my-essay/scorint.org/ProgramBook.pdf
Amoaka-Atta, S., & Hicks, D. (2002). Gis decision support-system for prevention of ballast
water borne specie introduction. Retrieved from
http://proceedings.esri.com/library/userconf/proc04/docs/pap1534.pdf
Andow, D. A. (2005). Characterizing ecological risks of introductions and invasions. In H.
Mooney, R. Mack, J. McNeely, L. Neville & P. Schei (Eds.), Invasive alien species
(pp. 84-103). Washington, D.C 20009: Island Press.
APHA , AWWA , & WPCF (1976 ) . Plankton: In – Standard Methods For the Examination
of Water and Wastewater, 14th ed., pp 1009-1029.
APHA. (1998). Standard methods for the examination of waste water (20th Ed.) American
Public Health Association, New York, pp. 1193.
Boltovskoy, E., & Wright, R. (1976). Recent foraminifera, (Junk. The Hague), (pp .515).
Boyd, C. E., & Lichkoppler. F. (1979). Water quality management in pond fish culture.
Auburn univ, Alabama, International for aquaculture. Agric. EXP. Station Research
and Development series, 22: 30
Boyds, C.E. (1979). Biology of Fishes. W.B. Sanders Coy. London (pp514).
California Environmental Protection Agency. State Water Resources Control Board,
(2002). Assessment of ballast water treatment technology for control of aquatic nonindigenous organisms. Retrieved from website:
https://monkessays.com/write-my-essay/calepa.ca.gov/publications/Reports/Mandated/2002/BallastWater.pdf
Carmago, J. A. (1992). Macro-invertebrates responses along the recovery gradient of a
regulated river (Spain) receiving an industrial effluent. Arch. Environ. Contam.
Toxicol. 23(pp324-332).
78
Chase, C., Reilly, C., & Pederson, J. (2000). Marine bioinvasions fact sheet: Ballast water
treatment options. Retrieved from Sea Grant website:
https://monkessays.com/write-my-essay/dongahusa.com/new/images/stories/ballast-treat.pdf
Chindah, A. C., Braide, S.A., & Izundu, E. 2005. Treatment of municipal wastewater quality
using sunlight. Caderno de Pesquisa. Ser. Bio. (Santa Cruz do Sul) 17 (2).(pp27-45).
Chiplonkar, S. A., & Rao, K. V. (2007). Analysis of variance. In K. Rao (Ed.), Biostatistics
(2nd ed., pp. 226-260). New Delhi, India: Jaypee Brothers Medical Publishers.
Coimbra, C. N., Graca, M.A.S., & Cortes, R.M. (1996). The effects of a basic effluent on
macroinvertebrate community structure in a temporary Mediteranean River. Environ.
Poll. 94 (3): (pp301-307).
Dangana, L.B. (1985). Hydro geomorphological controls of the mangrove environment in
parts of Rivers State. Proceedings of the mangrove ecosystem of the Niger-Delta
workshop. Eds. B.H.R. Wilcox and C.B. Powell. Pp6-23.
Deacutis, C.F., & Ribb, R. C. (2002). Ballast water and introduced species: Management
Options for Narragansett Bay and Rhode Island. Prepared to fulfill the requirements
of Chapter 46-17.3 of the Rhode Island General Laws Related to Ballast Water.
Dobroski, N., Scianni, C., Gehringer, D., & Falkner, M. California State L, Marine Facilities
Division. (2009). 2009 assessment of the efficacy, availability and environmental
impacts of ballast water treatment syatems for use in california waters. Retrieved
from website:
https://monkessays.com/write-my-essay/slc.ca.gov/spec_pub/mfd/ballast_water/documents/2009cslctechreportfin
al.pdf
Donner, P. (2010b). Is there a case for shore-based ballast water treatment facilities? In
Proceeding of the 5th International Conference & Exhibition: Ballast Water
Treatment 2010, 1-4 November 2010, Singapore.
Donner, P. (2010a). Ballast water treatment ashore brings more benefits. In Bellefontaine,
N.; Haag, F.; Linden, O. and Matheickal, J. (Eds.), Emerging ballast water
management systems (pp. 97-105). Malmo, Sweden: WMU Publications.
Dublin-Green, C.O. (1990). Seasonal variation in some physicochemical parameters of the
Bonny Estuary, Niger Delta, NIOMR Tech. paper 59 pp.21-25.
Egborge, A.M.B. (1994). Water pollution in Nigeria: Biodiversity and Chemistry of Warri
River. Ben Miller Books, Benin City, Nigeria.
Ekweozor, I.K.E. (1989). A review of the effect of oil pollution in West African
environment. Discovery and Innovation, (3). Pp27-37.
Fournier, C.(2004). Analysis of implementation of compulsory ballast water treatment for
the prevention of aquatic nuisance species, pp14.
79
GLOBALLAST. (2004). Ballast water treatment R & D directory. 2nd Edition.
International Maritime Organization. London. http://globallast.IMO.org. pp15.
GLOBBALLAST. (2012). Invasive aquatic species. Retrieved from
http://globallast.imo.org/index.asp
Gollasch, S. (1997).Removal of barriers to the effective implementation of ballast water
control and management measures in developing countries. pp195.
Gollasch, S., Lenz, J., Dammer, M., & Andres, H.G. (2000). Survival of tropical ballast
water organisms during a cruise from the Indian Ocean to the North Sea. Journal of
Plankton Research 22(5) 923-937. Retrieved from
http://plankt.oxfordjournals.org/content/22/5/923.full.pdf+html.
Hart, A.I., & Chindah, A.C. (1998). Preliminary study on the benthic macrofauna associated
with different microhabitats in mangrove forest of the Bonny estuary, Nigeria. Arch.
Hydrobiol. 40:pp9-15.
Hayes, K.R., and Hewitt, C. L. (1998). Risk assessment framework for ballast water
introductions. Centre for Research on Introduced Marine Pests. Technical Report
No.14. CSIRO Marine Laboratories, Hobert. pp81.
Hillman, S., Hoedt, F., & Schneide, P. CRC Reef Research Centre, (2004). The australian
pilot project for the treatment of ships’ ballast water . Retrieved from Final Report
for the Australian Government Department of the Environment and Heritage
website:
https://monkessays.com/write-my-essay/environment.gov.au/coasts/imps/publications/ballast/pubs/ballast.pdf
Humphrey, D. (2008). Characterization of ballast water as a vector for nonindigenous
zooplankton transport.Thesis Submitted to the University of British Colombia,
Canada for the Award of a Master of Science Degree, Retrieved from
https://circle.ubc.ca/bitstream/handle/2429/2391/ubc_2008_fall_humphrey_donald.p
df?sequence=1
Hydac International.(2008). Automatic pre-filtration in the treatment of ballast water.pp8.
International Maritime Organization (IMO). (2001).Stopping the ballast water stowaways.
Global Ballast Water Management Programme.
International Maritime Organization (IMO). (2005). International convention for the control
and management of ships’ ballast water and sediments. London.
International Maritime Organization (IMO). (2007, July 30). Report of the Marine
Environment Protection Committee on its fifty-sixth session (MEPC 56/23). London.
http://docs.imo.org/.
80
International Maritime Organization (IMO). (2008a, April 4). Report of the Marine
Environment Protection Committee on its fifty-seventh session (MEPC 57/21).
London. http://docs.imo.org/.
International Maritime Organization (IMO). (2008b, August 28). International Convention
for the control and management of ships’ ballast water and sediments, 2004.
Communication received from the Administration of the United Kingdom on behalf
of the contracting parties of the OSPAR and Helsinki Conventions (BWM.2/Circ.14).
London. http://docs.imo.org/.
International Maritime Organization (IMO). (2009). Guidelines for national ballast water
status assessments. Globallast Monograph Series No. 17.pp35.
INTERTANKO and International Chamber of Shipping. (1997). Model ballast water
management plan. Guidelines for the Control and Management of Ships’ Ballast
Water to Minimise the Transfer of Harmful Aquatic Organisms and Pathogens. pp42.
INTOSAI, Working Group on Environmental Auditing. (2007). Auditing biodiversity:
Guidance for Supreme Audit Institutions. pp129.
Invasive Species Advisory Committee (ISAC). National Invasive Species Council (NISC).
(2006). Invasive species definition clarification and guidance white paper . Retrieved
from website: https://monkessays.com/write-my-essay/invasivespeciesinfo.gov/docs/council/isacdef.pdf
Jalonen, R., & Salmi, K. (2009). Safety performance indicators for maritime safety
management: Literature review. Helsinki: Retrieved from
http://appmech.aalto.fi/fi/julkaisut/TKK-AM-9.pdf/
Jones, A.R. (1987). Temporal pattern in macrobenthic communities of the Hawkesbury
estuary, New South Wales. Aus. J. Mar. Fresh W. Res. 38:pp607-624.
Kazumi, J. (2007). Ballast water treatment technologies and their application for vessels
entering the great lakes via the st. lawrence seaway. Transportation Research Board
Special Report 291, 1-19. Retrieved from http://onlinepubs.trb.org
Kuzirian, A. M., Terry, E. C. S., Bechtel, D. L., & James, P. L. (2001). Hydrogen peroxide:
An effective treatment for ballast water. Biol. Bull. ,201, 297–299. Retrieved from
https://monkessays.com/write-my-essay/biolbull.org/content/201/2/297.full.pdf html.
Lafontaine, Y. D., Despatie, S., & Wiley, C. (2008). Effectiveness and potential
toxicological impact of the peracleans. Ecotoxicology and Environmental Safety,
(71), 355-369. Retrieved from www.elsevier.com/locate/ecoenv.
Lovell, S. J., & Stone, S. F. (2005) U.S Environmental Protection Agency. The economic
impacts of aquatic invasive species: A review of the literature. Retrieved from
National Centre for Environmental Economics website:
https://monkessays.com/write-my-essay/epa.gov/economics
81
Lucinda, C., & Martin, N. (1999). Oxford English mini-dictionary. Oxford Univ. Press Inc.
New York. pp200-535.
Mack, R. N., Simberloff, D., Lonsdale, W. M., Evans, H., Clout, M., & Bazzaz, F.
(2000). Biotic invasions: Causes, epidemiology, global consequences and control.
Ecological Applications 10,689–710. Retrieved from website: http://max2.ese.upsud.fr/epc/conservation/PDFs/BiolReviews.pdf
MARTOB Final report, (2004). Final publishable report. Retrieved from MRATOB
website: http://martob.ncl.ac.uk/public docs/ES-WP6/Final Publishable Report.pdf.
McKee, S. P., Levi, D. M., & Movshon, J. A. (2003). The nature and variety of visual
deficits in amblyopia. Journal of Vision, 3, 380–405.
McMullin, J.K., & Drew, D. (2007). Port of Milwaukee onshore ballast water treatment.
Feasibility Study Report. Prepared for Wisconsin Department of Natural Resources,
Milwaukee, Wisconsin. pp114.
McNeely, R. N., Neimanis, V.P., & Dwyer, L. (1979). Environmental Canada: Water quality
sourcebook- A guide to water quality parameters. pp112.
Minchin, D. (1997). Options available for the management of marine exotic species.
Retrieved from website:
https://monkessays.com/write-my-essay/dwaf.gov.za/wfw/Docs/Papers/options_available.pdf
Ministry of Environment, Lands and Parks Land Data BC. Land Use Task Force Resources
Inventory Committee. (1998). Guidelines for interpreting water quality data.
Retrieved from Resources Inventory Committee website:
https://monkessays.com/write-my-essay/ilmb.gov.bc.ca/risc/pubs/aquatic/interp/index.htm.
Miserendino, M. L. (2001). Macroinvertebrate assemblages in Andean Patagonian rivers and
streams. Hydrobiologia 444: 147–158.
Miskowski, D., Charlie, Q., & Dobranic, J. (2012).Bacteroides. Retrieved from
https://monkessays.com/write-my-essay/emsl.com/index.cfm?nav=Pages&ID=434.
Mitchell-Innes, B.A., & Pitcher, G.C (1992). Hydrographic parameters as indicatorsof the
suitability of phytoplankton populations as food herbivores copepods. In: Paynes,
A.I., Mann, K.H. and Hilborn, R. (eds). Benguala, South Africa Journal of Marine
Science. 12:pp355-365.
Moses, B.S. (1983). Introduction to tropical fisheries. Ibadan University
Press.UNESCO/ICSU Parts. pp102-105.
Motulsky, H.J, (2007). Prism 5 Statistics Guide, 2007- Statistical analyses for laboratory
and clinical researchers. GraphPad Software Inc., San Diego CA,
www.graphpad.com.
82
NEDECO, (1980). The water of the Niger Delta: Report of an investigation by NEDECO
(Netherlands engineering Consultants). The Hague. pp210-228.
Newell, G.E., & Newell, R.C (1977). Marine Plankton (a practical guide). Hutchinson,
London, 244pp. ISBN 009 131 871 8.
NRC, National Research Council. (1996). Stemming the tide: Controlling introductions of
nonindigenous species by ships\\. Washington, DC: National Academy of Sciences.
Odokuma, L.O., & Okpokwasili, G.C. (1996). Tolerance of nitrobacter to toxicity of
hydrocarbon fuels. Journal of petroleum science and engineering 16, pp89-93.
O’Neill, H. J., McKim, M., Allen, J., & Choate, J. (1994). Environment Canada. Monitoring
of surface water quality: A guide for citizens, students and communities in atlantic
canada. Retrieved from Canada-New Brunswick Water/Economy Arrangement
website:. https://monkessays.com/write-my-essay/ec.gc.ca/Publications/98126669-2E4D-4E2E-9273-
DC23FD59F452waterquality_e.pdf.
Orr, R. (2003). Generic nonindigenous aquatic organisms risk analysis review process. In G.
Ruiz & J. Carlton (Eds.), Invasive Species: Vectors and Management Strategies (pp.
415-431). Washington: Island Press.
Oyewo, E.O., & Don-Pedro, K.N. (2003). Influence of salinity variability on heavy metal
toxicity of three estuarine organisms. J. Nigeria Envi. Sci. 1(2), pp141-155.
Parker, N.C., & Davis, K.B. (1981). Requirements of warm water fish. In: proceedings of
the Bioengineering Symposium for fish culture. FCS Pub. 1:pp21-28.
Parsons, M.G., & Harkins R. W. (2002). Full-Scale Particle Removal Performance of Three
Types of Mechanical Separation Devices for the Primary Treatment of Ballast Water.
Marine Technology, 39:211-222.
Pavliha, M., David, M., & Andrijasic, A. (2003). Ballast water management- Legislative
Review. Faculty of Maritime Studies and Transportation, University of Ljubljana,
Slovenia.
Pereira, N.N., Botter, R.C., Brinati, H.L., & Trevis, E.F. (2010). In B Kjerve (Chair). Ballast
water treatment ashore brings more benefits. In Bellefontaine, N.; Haag, F.; Linden,
O. and Matheickal, J. (Eds.), Emerging ballast water management systems (pp. 97-
105). Malmo, Sweden: WMU Publications.
Philips, S. (2006). Pacific States Marine Fisheries Commission Portland, Oregon. Ballast
water issue paper. Retrieved from website:
https://monkessays.com/write-my-essay/aquaticnuisance.org/wordpress/wpcontent/uploads/2009/01/ballast_water_i
ssue_paper.pdf.
83
Pombo, L., Elliot, M., & Rebelo, J. E. (2005). Environmental influences on fish assemblage
distribution of an estuarine coastal lagoon, Ria de Aveiro (Portugal). Scientia
Marina, 69(1), 143-159.
PSWRCAC. Prince William Sound Regional Citizens Advisory Council (2005). Ballast
water treatment methods. Fact Sheets
Raaymakers, S. (2002, December). The ballast water problem: Global ecological, economic
and human health impacts. Paper presented at the RECSO/IMO Joint Seminar on
Tanker Ballast Water Management and Technologies Global ballast water
management programme. Retrieved from
https://monkessays.com/write-my-essay/imo.org/blast/blastDataHelper.asp?data_id=8595&filename=Raaymakers
GlobalImpactsPaper.pdf
Rejmanek, M, Richardson, D.M., Higgins, S.I., Pitcairn, M.J., & Grotkopp, E. (2005).
Ecology of invasive plants: State of the art. In H. Mooney, R. Mack, J. McNeely, L.
Neville & P. Schei (Eds.), Invasive alien species (pp. 104-161). Washington, D.C
20009: Island Press.
Ricciardi , A., Jones, L. A., Kestrup, A. M., & Ward, J. M. (2011). Expanding the propagule
pressure concept to understand the impact of biological invasions. Fifty years of
invasion ecology: The legacy of Charles Elton, (1), 225-235. Retrieved from
http://redpath-staff.mcgill.ca/ricciardi/Ricciardi_Elton_C17.pdf.
Rigby, G., & Taylor, A. (1998). Ballast water treatment to minimise the risks of introducing
nonidigenous marine organisms into Australian Ports. Review of Current
Technologies and Comparative Indicative Costs of Practical Options. pp86.
Rigby, G., & Taylor, A. (1999). Progress in the management and treatment of ships’ ballast
water to minimize the risks of translocating harmful nonindigenous aquatic
organisms.
Romane, A., & Schlieper, C. (1971). Biology of Brackish Water. Wiley. pp211.
Ruiz, G., & Carlton, J. T. (2003). Invasion vectors: A conceptual framework for
management. In G. Ruiz & J. Carlton (Eds.), Invasive Species: Vectors and
Management Strategies (pp. 459-504). Washington: Island Press.
Ruiz, G., & Reid, D. F., (2007). Current state of understanding about the effectiveness of
ballast water exchange (BWE) in reducing aquatic nonindigenous species (ANS)
introductions to the great lakes basin and Chesapeake bay, USA: Synthesis and
analysis of existing information . NOAA Technical Memorandum GLERL-142
Retrieved from website:
https://monkessays.com/write-my-essay/klgates.com/fcwsite/ballast_water/technical/noaa_understanding.pdf
Ruiz, G., Smith, G. E., & Systma, M. (2006). Workshop report on testing of ballast water
treatment systems: General Guidelines and Step-wise Strategy Toward Shipboard
Testing (June 14-16 2005, Portland, Oregon).pp30.
84
Sano, L.L., Maupili, M.A., Krueger, A., Garcia, E., Gossiaux, D., Phillips, K., & Landrum,
P.F. (2004). Comparative efficacy of potential chemical disinfectants for treating
unballasted vessels. J. Great Lakes Res. 30:201–216.
Sassi, J., Viitasalo, S., Rytkonen, J., & Leppakoski, E. (2005). Experiments with ultraviolet
light, ultrasound and ozone technologies for onboard ballast water treatment.pp86.
Scott, K. (2008). Managing alien invasive species under the 2004 ballast water convention- a
new zealand perspective. The Journal of International Maritime Law, 14, 307-330.
Shuo, M. (2011). Maritime economics. (pp. 13-14). Malmo, Sweden: World Maritime
University.
Sikoki, F .D., & Zabbey, N. ( 2006). Environmental gradients and Benthic community of the
middle reaches of Imo River, Sout h – Eastern Nigeria . Environ . Ecol., 24 (1):32-
36.
Sikoki, F.D., & Veen, J.V. (2004). Aspects of water quality and the potential for fish
production of Shiroro Reservior, Nigeria, Liv Sys. Dev. pp2-7.
Snowden, R.J., & Ekweozor, I.K.E (1990). Littoral Infauna of a West African estuary: An
Oil Pollution Baseline Survey. Mar. Biol. 105:pp51-57.
Snowden, R.J., & Ekweozor, I.K.E. 1987. The impact of a minor oil spillage in the Estuarine
Niger Delta. Mar. Pollut. Bull. 18(11): 595–599.
Swingle, H.S. (1969). Methods of analysis for waters, organic matter and pond bottom soils
used in fisheries research, Auburn University, Auburn, Alabama. pp119.
Tamburri, M. N.,Wasson, K., & Matsuda, M. (2001).Ballast water deoxygenation can
prevent aquatic introductions while reducing ship corrosion. Journal of Biological
Conservation 103 (2002) pp331–341.
Tyokumbur, E.T., Okorie, E.T., & Ugwumba, O.A. (2002). Limnological assessment of the
effects of effluents on macroinvertebrate fauna in Awba stream and Reservoir,
Ibadan, Nigeria. The Zoologist, 1(2): 59-62.
UNCLOS. (1982). United nations convention on the law of the sea. Retrieved from United
Nations website:
https://monkessays.com/write-my-essay/un.org/depts/los/convention_agreements/texts/unclos/unclos_e.pdf
UNEP. United Nations Environment Programme, (1999). Alien species: Guiding principle
for the prevention, introduction and mitigation of impacts. Retrieved from website:
https://monkessays.com/write-my-essay/cbd.int/doc/meetings/sbstta/sbstta-05/official/sbstta-05-05-en.pdf
United Nations. (1992b, June 14). The Rio Declaration on Environment and Development.
https://monkessays.com/write-my-essay/unescap.org/esd/environment/rio20/pages/Download/Rio_DeclarationE.pdf
85
United Nations. (1992a, May 22). Convention on Biological Diversity.
https://monkessays.com/write-my-essay/cbd.int/convention/text/
United Nations. (2002, September). Report of the world summit on sustainable development.
Johannesburg, South Africa, 26 August- 4 September 2002 Earth summit,
Johannesburg, South Africa. Retrieved from
https://monkessays.com/write-my-essay/johannesburgsummit.org/html/documents/summit_docs/131302_wssd_re
port_reissued.pdf.
USEPA. US Environmental Protection Agency, (1999). Turbidity standard method guidance
manual. Retrieved from website:
water.epa.gov/lawsregs/rulesregs/sdwa/mdbp/../app_c.doc.
Veldhuis, M., Hallers, C., Riviere, E. B., Fuhr, F., Finke, J., Steehouwer, P. P., Star, I., &
Sloote, C. (2010). In B Kjerve (Chair). Ballast water treatment ashore brings more
benefits. In Bellefontaine, N.; Haag, F.; Linden, O. and Matheickal, J.
(Eds.), Emerging ballast water management systems (pp. 97-105). Malmo, Sweden:
WMU Publications.
Verma, P.S., & Agarwal , V.K , ( 2006 ) . Ecology : In Cell Biology , Genetics , Molecular
Biology , Evolution and Ecology . 14th ed. ( Multicolor) , S . Chard and Company
Ltd, Ram Nagar , New Delhi, pp1 – 294.
Voigt, M., & Gollasch, S. (2001). Proposed standards for evaluating ballast water treatment
options. Proceedings of the First International Ballast Water Treatment Standards
Workshop. IMO, London. 28-30 March 2001, pp 35-43.
Waite, T. D., & Kazumi, J. (2001a). Possible ballast water treatment standards: An
engineering perspective. Proceedings of the First International Ballast Water
Treatment Standards Workshop. IMO, London. 28-30 March 2001, pp.17-22.
Waite, T.D., & Kazumi, J. (2001b). Ballast water treatment standards: Concept and Issues.
Proceedings of the Second International Conference on Marine Bioinvasions, New
Orleans, La., April 9-11, 2001, pp. 143-144.
Wesley, W., Chang, P., Verosto, S., Atsavapranee, P., Reid, D. F., & Jenkins, P. T. (2006).
Computational and experimental analysis of ballast water exchange . Naval
Engineering Journal, 3, 25-36.
Williamson, M., & Fitter, A. (1996). The varying success of invaders. Ecology, 77(6), 1662-
1666. Retrieved from
https://monkessays.com/write-my-essay/planta.cn/forum/files_planta/the_varying_success_of_invaders_923.pdf.
Wittenberg, R., & Cock, M.J. (2005). Best practices for the prevention and management of
invasive alien species. In H. Mooney, R. Mack, J. McNeely, L. Neville & P. Schei
(Eds.), Invasive alien species (pp. 209-232). Washington, D.C 20009: Island Press.
86
Wonham, M.J., Walton, W., Ruiz, G.M., Frese, A.M., & Galil, B.S. (2001). Going to the
source: role of the invasion pathway in determining potential invaders. Mar. Ecol.
Prog. Ser. 215: 1-12. Retrieved from https://monkessays.com/write-my-essay/intres.com/articles/meps/215/m215p001.pdf.
Xie, Y., & Chen, P. (2004). Crumb rubber filtration for ballast water treatment: A
preliminary study . , Singapore. Retrieved from http://water.usgs.gov/wrri/02-
03grants_new/prog-compl-reports/2003PA11B.pdf
Zabbey, N. (2002). An ecological survey of benthic macro invertebrates of Woji Creek, off
the Bonny River System Rivers State. M.Sc. Thesis, University of Port Harcourt, pp:
102.
Zabbey, N., & Hart, A.Z. (2006). Influence of some physicochemical parameters on the
composition and distribution of benthic fauna in Woji Creek, Niger Delta, Nigeria.
Global J. Pure Appl. Sci., 12(1): 1-5.
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APPENDICES
Appendix A: PHYSICOCHEMICAL PARAMETERS
Using Multi Parameter Water Checker (Horiba), Spec: U-10 µ
Date of sample collection: Tue 3rd January 2012 and Fri 6th January 2012
Port Harcourt Harbour, Nigeria
S
/
N
STATION
CODE
PARAMETERS
PH COND
(µscm1
)
TURB
(NTU)
TEMPT
(
oC)
SALINITY
(0/00)
DO
(mg/l)
TDS
(mg/l)
1 NP1 7.5
1
33600 3.0 29.1 21.2 6.7 23520
2 NP2 7.7
3
33700 3.0 29.2 21.3 6.6 23590
3 OK1 7.6
3
34600 1.0 29.1 21.9 7.7 24220
4 OK2 7.6
4
34900 1.0 29.0 22.1 7.7 24430
KEY:
NP1: Main Harbour (Upstream), Port Harcourt, Nigeria
NP2: Main Harbour (downstream), Port Harcourt, Nigeria
OK1: Okrika Oil Terminal (upstream), Port Harcourt, Nigeria
OK2: Okrika Oil Terminal (downstream), Port Harcourt, Nigeria
88
Appendix B: PHYTOPLANKTON TAXONOMIC LIST
Table 1: The Phytoplankton taxonomic list and the number of individuals in the different stations
within the study area [ No. of individual organisms / mL ] in Dry season .
STATION
OK1 OK2 NP1 NP2 TOTAL
BACILLARIOPHYCEAE (C)
CENTRICAE (Sc)
Cosinodiscus lineatus 200 3000 100 500 3800
Cosinodiscus radiatus 1000 400 100 100 1600
Cyclotella sp., 0 0 500 100 600
Cyclotella meneglunii 500 1500 200 300 2500
Hyalodiscus subtilis 200 1000 100 0 1300
TOTAL CENTRICAE 1900 5900 1000 1000 9800
PENNATAE (Sc)
Gyrosigma acuminatum 1300 1000 300 500 3100
Hydrosira triquetra 400 1000 100 200 1700
Navicula sp., 0 0 0 0 0
Nitzschia hungarica 500 300 200 100 1100
Pinnularia microstauron 0 0 0 0 0
Pinnularia sp., 0 0 0 0 0
Stauroneis sp., 0 0 0 0 0
Surirella sp., 0 0 0 0 0
Synedra acus 100 200 500 100 900
Synedra ulna 500 1000 200 100 1800
Synedra sp. 100 300 100 200 700
TOTAL PENNATAE 2900 3800 1400 120 0 9300
CYANOPHYCEAE
Anabaena sp., 0 0 0 0 0
Spirulina sp., 0 0 0 0 0
TOTAL CYANOPHYCEAE 0 0 0 0 0
DESMIDIACEAE
Closterium sp. 1200 1000 200 100 2500
Closterium ehrenbergii 1700 600 100 300 2700
TOTAL DESMIDIACEAE 2900 1600 300 400 5200
HARMFUL DINOFLAGELLATES
Alexandrium minutum – Cyst (Lebour) Balech 500 1000 2000 1000 4500
TOTAL HARMFUL DINOFLAGELATES 500 1000 2000 1000 4500
Phytoplanktons 8200 12300 4700 3600 28800
No. of ocurring Species 13 13 14 13
Note :Class (C); Subclass (Sc); R.A-Relative Abundance; RDO-Relative Dominance (Cover);DDensity OK=Okrika Oil Jetty NP= General Cargo Terminal
89
Appendix C: ZOOPLANKTON TAXONOMIC LIST
Table 2: Zooplankton taxonomic list and the number of individuals in the different stations
within the study area (No. of individual organisms/mL ) in Dry season .
STATION
OK1 OK2 NP1 NP2 TOTAL D RDO
TAXA
PROTOZOA
CRUSTACEA (C)
CALANOID COPEPODA (Sc)
Acartia clausii 500 100 3000 1000 4600 1150.0 6.9
Calanus sp. 1000 700 1300 600 3600 900.0 5.4
Calanus finmarchicus 3000 500 9000 1000 13500 3375.0 20.1
Candacia pachydactyla 500 100 1000 600 2200 550.0 3.3
Eucalanus sp. 4000 200 800 1000 6000 1500.0 8.9
Microcalanus pusillus 200 1000 200 100 1500 375.0 2.2
Paracalanus pygmaeus 3000 5000 10,000 5000 23000 5750.0 34.3
Pseudocalanus elongatus 1000 300 100 200 1600 400.0 2.4
Temora turbinate 300 0 0 2000 2300 575.0 3.4
Tortanus sp., 100 100 500 1000 1700 425.0 2.5
Total Calanoid Copepod 13600 8000 25900 12500 60000 15000.0 89.4
CYCLOPODA COPEPOD
Oncaea sp., 3000 0 100 0 3100 775.0 4.6
Total Cyclopoda 3000 0 100 0 3100 775.0 4.6
CRUSTACEAN Larva
Nauplius larva 1000 100 0 500 1600 400.0 2.4
Ostracod larva 400 0 300 100 800 200.0 1.2
Cirripede cypris larva 100 200 0 200 500 125.0 0.7
Penaeid nauplius 500 200 300 100 1100 275.0 1.6
Total Crustacean Larva 2000 500 600 900 4000 1000.0 6.0
Total Zooplanktons 18600 8500 26600 13400 67100 16775.0 100.0
No. of species 15 12 12 14
Note ;Phylum (P) ;Subphylum (Sp) ; Class (C); Subclass (Sc);
Suborder (So) ;Order (O): D- Density: RDO-Relative Dominance
(Cover)
OKJ=Okrika Oil Jetty
NP= General Cargo Terminal
90
Appendix D: SUMMARY OF THE ORIGIN, ECOLOGICAL, ECONOMIC,
AND HEALTH IMPACTS OF SOME HARMFUL AQUATIC ORGANISMS
AND PATHOGENS (HAOP):
POLYGENY EXOTIC
SPECIES
ECOLOGICAL
IMPACT
ECONOMI
C IMPACT
OTHERS COMMON
NAMES
ORIGIN
MOLLUSC Dreissena
polymorpha
They compete
with zooplankton
for food, thus
affecting natural
food webs. They
also interfere
with the
ecological
functions of
native molluscs.
cause great
economic
damage
Zebra mussels native to the
Caspian and
Black Seas
Euglandina
rosea
It’s a biological
control agent.
Many Partulid
tree snails have
been lost already
and today the
survivors exist in
zoos and in the
world’s first
wildlife reserves
for snails. This
invasion by a
biological
control agent
has caused a
significant loss
of biodiversity
a biological
control agent
for another
alien species,
the giant
African snail
(Achatina
fulica) and the
the Partulid tree
snails
cannibal
snail, rosy
wolf snail
Native to
the
southeaster
n United
States
Mytilus
galloprovincialis
It has succeeded
in establishing
itself at widely
distributed points
around the globe,
with nearly all
introductions
occurring in
temperate regions
and at localities
where there are
large shipping
ports (Branch and
Stephanni 2004).
Ship hull fouling
and transport of
ballast water have
been implicated in
its spread and its
impact on native
communities and
native mussels has
been suggested by
a number of
studies and
observations
bay mussel,
blue mussel,
Mediterranea
n mussel
native to the
Mediterrane
an coast
and the
Black and
Adriatic
Seas
Pomacea
canaliculata
poses a serious
threat to many
wetlands around
a freshwater
snail with a
voracious
apple snail,
channeled
apple snail,
native South
America
91
the world
through
potential habitat
modification and
competition with
native species.
appetite for
water plants
including
lotus, water
chestnut, taro
and rice , it
is a major
crop pest in
south east
Asia
(primarily in
rice) and
Hawaii (taro)
golden apple
snail, miracle
snail
Corbula
amurensis
it has been
designated as a
major bilogical
disturbance with
significant
ecological
consequences in
the San
Francisco Bay
area of
California where
large
populations have
become
established.
Amur river
clam, Amur
river corbula,
Asian bivalve,
Asian clam,
brackishwater corbula,
Chinese clam,
marine clam
native to
Japan,
China and
Korea
FISH
Clarias
batrachus
C. batrachus has
been described
as a benthic,
nocturnal, tactile
omnivore that
consumes
detritus and
opportunistically
forages on large
aquatic insects,
tadpoles, and
fish.
During a
drought large
numbers of
walking
catfish may
congregate in
isolated
pools and
consume
other species.
They are
known to
have invaded
aquaculture
farms,
entering
ponds where
they prey on
fish stocks
is an
opportunistic
feeder and can
go for months
without food
clarias
catfish,
climbing
perch,
freshwater
catfish,
Thailand
catfish,
walking
catfish,
native to
southeaster
n Asia
Cyprinus carpio It is considered a
pest because of
its abundance
and its tendency
to destroy and
uproot the
aquatic
vegetation used
as habitat by a
variety of
species.
Reduces water
clarity
Common
carp, scale
carp, grass
carp, wild
carp, German
carp,
European
carp.
Native of
Western
Europe.
92
Gambusia affinis It has become a
pest in many
waterways
around the
world following
initial
introductions
early last
century as a
biological
control of
mosquito.
Mosquito fish
are difficult to
eliminate once
established,
The highly
predatory
mosquito fish
eats the eggs
of
economically
desirable fish
and preys on
and
endangers
rare
indigenous
fish and
invertebrate
species.
Live-bearing
tooth-carp,
Mosquito fish,
Topminnow,
western
mosquitofish,
Western
mosquitofish
a small fish
native to the
fresh waters
of the
eastern and
southern
United
States
Micropterus
salmoides
places
introduced
Micropterus
salmoides have
affected
populations of
small native fish
through
predation,
sometimes
resulting in the
their decline or
extinction
Its diet
includes fish,
crayfish,
amphibians
and insects.
American
black bass,
black
bass,green
bass,
largemouth
bass,
largemouth
black bass
has been
widely
introduced
throughout
the world
due to its
appeal as a
sport fish
and for its
tasty flesh
Salmo trutta It is blamed for
reducing native
fish populations,
especially other
salmonids,
through
predation,
displacement
and food
competition
It is a popular
angling fish.
brook trout,
brown trout,
orange fin,
peal, salmon
trout, sea
trout, whiting
Salmo trutta
has been
introduced
around the
world for
aquaculture
and stocked
for sport
fisheries
CRUSTACEAN
Carcinus maenas in some
locations of its
introduced range
it has caused the
decline of other
crab and bivalve
species
It is a
voracious
food
generalist
European
shore crab,
green crab
is native to
Europe and
northern
Africa
Cercopagis
pengoi
Cercopagis
pengoi is a
voracious
predator and
may compete
with other
planktivorous
invertebrates
and vertebrates.
Through this
competition,
Cercopagis
pengoi has
the potential
to affect the
abundance
and condition
of
zooplanktivor
ous fish and
fish larvae. It
fishhook
waterfle
is a water
flea native
to the
PontoAraloCaspian
basin in
South
Eastern
Europe, at
the meeting
point of the
93
also
interferes
with fisheries
by clogging
nets and
fishing gear.
Middle
East,
Europe and
Asia
Eriocheir
sinensis
It contributes to
the local
extinction of
native
invertebrates
and modifies
habitats
the crab may
cost fisheries
and
aquaculture
industries
several of
hundreds of
thousands of
dollars per
year by
stealing bait
and feeding
on trapped
fish.
has invaded
Europe and,
more recently,
North America,
causing erosion
by its intensive
burrowing
activity,
Chinese
freshwater
edible crab,
Chinese
mitten crab
Chinese
ALGAE
Caulerpa
taxifolia
Caulerpa
taxifolia forms
dense
monocultures
that prevent the
establishment of
native seaweeds
excludes
almost all
marine life,
affecting the
livelihoods of
local
fishermen.
widely used as a
decorative plant
in aquaria
killer alga,
sea weed
French
Undaria
pinnatifida
It is an
opportunistic
weed which
spreads mainly
by fouling ship
hulls. It forms
dense
underwater
forests, resulting
in competition
for light and
space which may
lead to the
exclusion or
displacement of
native plant and
animal species.
it is cultivated
for human
consumption.
apron-ribbon
vegetable,
Asian kelp,
Japanese kelp
The kelp
(Undaria
pinnatifida)
is native to
Japan
FUNGUS
Aphanomyces
astaci
The parasitic
fungus A. astaci
was introduced
into Europe by
imports of North
American
species of
crayfish. Native
European
crayfish
populations are
not resistant to
the fungus.
It has since
devastated
native
crayfish
stocks
throughout
the continent.
is commonly
referred to as
crayfish
plague
This fungus
is endemic
of North
America
and it is
carried by
North
American
species, i.e.
signal
crayfish
Pacifastacu
s
94
leniusculus,
Procambaru
s clarkii and
Orconectes
limosus.
AQUATIC
PLANT
Eichhornia
crassipes
Water hyacinth
also prevents
sunlight and
oxygen from
reaching the
water column
and submerged
plants. Its
shading and
crowding of
native aquatic
plants
dramatically
reduces
biological
diversity in
aquatic
ecosystems.
Water
hyacinth is a
very fast
growing
plant, with
populations
known to
double in as
little as 12
days.
Infestations
of this weed
block
waterways,
limiting boat
traffic,
swimming
and fishing
Eichhornia
crassipes is one
of the worst
aquatic weeds
in the world. Its
beautiful, large
purple and
violet flowers
make it a
popular
ornamental
plant for ponds.
It is now found
in more than 50
countries on five
continents
floating water
hyacinth,
water
hyacinth,
water orchid
Originally
from South
America
COMB JELLY
Mnemiopsis
leidyi
The ctenophore,
Mnemiopsis
ledyi, is a major
carnivorous
predator of
edible
zooplankton
(including
meroplankton),
pelagic fish eggs
and larvae.
In the early
1980s, it was
accidentally
introduced via
the ballast water
of ships to the
Black Sea, where
it had a
catastrophic
effect on the
entire ecosystem
is associated
with fishery
crashes
American
comb jelly,
comb jelly,
comb jellyfish,
sea
gooseberry,
sea walnut,
Venus’ girdle,
warty comb
jelly
it is
indigenous
to
temperate,
subtropical
estuaries
along the
Atlantic
coast of
North and
South
America.
AMPHIBIAN
Rana
catesbeiana
Primary
concerns are
competition
with, and
predation upon,
native
herpetofauna.
has been widely
distributed via
aquaculture and
the aquarium
trade. It is one
of the most
frequently
cultivated edible
frogs worldwide
bullfrog,
North
American
bullfrog
North
American
SEA STAR
95
Asterias
amurensis
The seastar will
eat a wide range
of prey and has
the potential for
ecological harm.
The seastar
will eat a
wide range of
prey and has
the potential
for economic
harm in its
introduced
range
Flatbottom
seastar,
Japanese
Seastar,
Japanese
starfish,North
Pacific
seastar,
northern
Pacific
seastar,
purple-orange
seastar
Originally
found in far
north
Pacific
waters and
areas
surrounding
Japan,
Russia,
North
China, and
Korea,
96
Appendix E: SUMMARY OF STATISTICAL ANALYSIS RESULTS OF
FIELD DATA USING GRAPHPAD INSTAT® VERSION 3.10 STATISTICAL
SOFTWARE.
Summary of Statistical Analysis of Physiochemical Properties

T-test (one sample T-test)

Number Standard
of Standard Error of
Group Points Mean Deviation Mean Median
=============== ====== ======== ========= ======== ========
PH 4 7.628 0.09032 0.04516 7.635
COND 4 34200 648.07 324.04 34150
TURB 4 2.000 1.155 0.5774 2.000
TEMPT 4 29.100 0.08165 0.04082 29.100
SALINITY 4 21.625 0.4425 0.2213 21.600
DO 4 7.175 0.6076 0.3038 7.200
TDS 4 23940 453.65 226.83 23905
95% Confidence Interval
Group Minimum Maximum From To
=============== ======== ======== ========== ==========
PH 7.510 7.730 7.484 7.771
COND 33600 34900 33169 35231
TURB 1.000 3.000 0.1629 3.837
TEMPT 29.000 29.200 28.970 29.230
SALINITY 21.200 22.100 20.921 22.329
DO 6.600 7.700 6.208 8.142
TDS 23520 24430 23218 24662

Summary of Results of Statistical Analysis of Phytoplankton Data
One-way Analysis of Variance (ANOVA)
The P value is 0.0007, considered extremely significant.
Variation among column means is significantly greater than expected by chance.
Tukey-Kramer Multiple Comparisons Test
If the value of q is greater than 3.759 then the P value is less than 0.05.
Mean
Comparison Difference q P value
================================== ========== ======= ===========
OK1 vs OK2 0.001494 1.739 ns P>0.05
OK1 vs NP1 -0.003151 3.667 ns P>0.05
OK1 vs NP2 -0.002708 3.151 ns P>0.05
OK2 vs NP1 -0.004645 5.406 ** P<0.01
OK2 vs NP2 -0.004202 4.890 ** P<0.01
NP1 vs NP2 0.0004429 0.5154 ns P>0.05
97
Mean 95% Confidence Interval
Difference Difference From To
================================== ========== ======= =======
OK1 – OK2 0.001494 -0.001735 0.004724
OK1 – NP1 -0.003151 -0.006380 7.906E-05
OK1 – NP2 -0.002708 -0.005938 0.0005219
OK2 – NP1 -0.004645 -0.007875 -0.001415
OK2 – NP2 -0.004202 -0.007432 -0.0009724
NP1 – NP2 0.0004429 -0.002787 0.003673
Assumption test:: Are the standard deviations of the groups equal?
ANOVA assumes that the data are sampled from populations with identical SDs. This assumption is
tested using the method of Bartlett.
Bartlett statistic (corrected) = 12.452
The P value is 0.0060.
Bartlett’s test suggests that the differences among the SDs are very significant.
Since ANOVA assumes populations with equal SDs, you should consider transforming your data
(reciprocal or log) or selecting a nonparametric test.
Assumption test:: Are the data sampled from Gaussian distributions?
ANOVA assumes that the data are sampled from populations that follow Gaussian distributions. This
assumption is tested using the method Kolmogorov and Smirnov:
Group KS P Value Passed normality test?
=============== ====== ======== =======================
OK1 0.2897 0.0023 No
OK2 0.3160 0.0005 No
NP1 0.2784 0.0043 No
NP2 0.2817 0.0036 No
At least one column failed the normality test with P<0.05.
Consider using a nonparametric test or transforming the data (i.e. converting to logarithms or
reciprocals).
Intermediate calculations. ANOVA table
Source of Degrees of Sum of Mean
Variation freedom squares square
============================ ========== ======== ========
Treatments (between columns) 3 0.0002062 6.874E-05
Residuals (within columns) 52 0.0005376 1.033E-05
—————————- ———- ——–
Total 55 0.0007438
F = 6.650 =(MStreatment/MSresidual)
98
Summary of Data
Number Standard
of Standard Error of
Group Points Mean Deviation Mean Median
=============== ====== ======== ========= ======== ========
OK1 14 0.003121 0.003264 0.0008725 0.002000
OK2 14 0.001626 0.001396 0.0003732 0.001000
NP1 14 0.006271 0.003600 0.0009622 0.005000
NP2 14 0.005829 0.003973 0.001062 0.005000
95% Confidence Interval
Group Minimum Maximum From To
=============== ======== ======== ========== ==========
OK1 0.000 0.01000 0.001236 0.005005
OK2 0.000 0.005000 0.0008204 0.002432
NP1 0.0005000 0.01000 0.004193 0.008350
NP2 0.000 0.01000 0.003535 0.008122
* * *

Summary of Results of Statistical Analysis of Zooplankton Data
One-way Analysis of Variance (ANOVA)
The P value is 0.7468, considered not significant.
Variation among column means is not significantly greater than expected by chance.
Post tests
Post tests were not calculated because the P value was greater than 0.05.
Assumption test: Are the standard deviations of the groups equal?
ANOVA assumes that the data are sampled from populations with identical SDs. This assumption is
tested using the method of Bartlett.
Bartlett statistic (corrected) = 0.7438
The P value is 0.8628.
Bartlett’s test suggests that the differences among the SDs is not significant.
Assumption test: Are the data sampled from Gaussian distributions?
ANOVA assumes that the data are sampled from populations that follow Gaussian distributions. This
assumption is tested using the method
Kolmogorov and Smirnov:
Group KS P Value Passed normality test?
99
=============== ====== ======== =======================
NP1 0.2625 0.0065 No
NP2 0.1910 >0.10 Yes
OK1 0.2218 0.0455 No
OK2 0.3058 0.0005 No
At least one column failed the normality test with P<0.05.
Consider using a nonparametric test or transforming the data (i.e. converting to logarithms or
reciprocals).
Intermediate calculations. ANOVA table
Source of Degrees of Sum of Mean
variation freedom squares square
============================ ========== ======== ========
Treatments (between columns) 3 1.706E-05 5.685E-06
Residuals (within columns) 56 0.0007776 1.388E-05
—————————- ———- ——–
Total 59 0.0007946
F = 0.4094 =(MStreatment/MSresidual)
Summary of Data
Number Standard
of Standard Error of
Group Points Mean Deviation Mean Median
=============== ====== ======== ========= ======== ========
NP1 15 0.002736 0.003221 0.0008316 0.002000
NP2 15 0.004195 0.004044 0.001044 0.003300
OK1 15 0.003137 0.003840 0.0009914 0.001250
OK2 15 0.003336 0.003751 0.0009684 0.001670
95% Confidence Interval
Group Minimum Maximum From To
=============== ======== ======== ========== ==========
NP1 0.0002500 0.01000 0.0009521 0.004520
NP2 0.000 0.01000 0.001956 0.006435
OK1 0.000 0.01000 0.001011 0.005264
OK2 0.000 0.01000 0.001259 0.005413
* * *
100
Appendix F: FULL TEXT OF IMO AND UN CONVENTIONS MENTIONED
IN THE STUDY
International Maritime Organization (IMO) Conventions
Ballast Water Management Convention (BWMC)
Regulation D-1: Ballast Water Exchange (BWE)
Regulation D-1 requires ballast water exchange with 95% volumetric efficiency, which is
assumed to be achieved after a throughput of three times the ballast water volume.
The regulation stipulates also that, whenever possible, ballast water exchange must
occur at least 200 nautical miles offshore and in at least 200 m depth of water. If this
is not possible due to the ship’s route, exchange must occur at least 50 nautical miles
offshore and in at least 200 m depth of water. Port States are required also by this
regulation to designate “exchange zones” with a lesser distance and depth.
Regulation D-2: Ballast Water Performance Standard
Regulation D-2 requires ballast water treatment results to have less than 10 viable organisms
per cubic meter for organisms of size greater than or equal to 50 microns. It also
requires ballast water treatment to result in less than 10 viable organisms per
milliliter for organisms of size less than 50 microns as summarized in Figure 1.6.
The regulation sets three indicator micron discharge limits (human health standard): Less
than one colony-forming unit (cfu) of toxicogenic vibrio cholerae per 100 ml or less
than one cfu per gram (wet weight); less than 250 cfu of Escherichia coli per 100 ml;
and less than 100 cfu of intestinal enterococci per 100 ml (Figure 1.6).
Regulation B-3 Ballast Water Management for Ships
1 A ship constructed before 2009:
.1 with a Ballast Water Capacity of between 1,500 and 5,000 cubic metres, inclusive, shall
conduct Ballast Water Management that at least meets the standard described in
regulation D-1 or regulation D-2 until 2014, after which time it shall at least meet the
standard described in regulation D-2;
.2 with a Ballast Water Capacity of less than 1,500 or greater than 5,000 cubic metres shall
conduct Ballast Water Management that at least meets the standard described in
regulation D-1 or regulation D-2 until 2016, after which time it shall at least meet the
standard described in regulation D-2.
101
2 A ship to which paragraph 1 applies shall comply with paragraph 1 not later than the first
intermediate or renewal survey, whichever occurs first, after the anniversary date of
delivery of the ship in the year of compliance with the standard applicable to the
ship.
3 A ship constructed in or after 2009 with a Ballast Water Capacity of less than 5,000 cubic
metres shall conduct Ballast Water Management that at least meets the standard
described in regulation D-2.
4 A ship constructed in or after 2009, but before 2012, with a Ballast Water Capacity of
5,000 cubic metres or more shall conduct Ballast Water Management in accordance
with paragraph 1.2.
5 A ship constructed in or after 2012 with a Ballast Water Capacity of 5000 cubic metres or
more shall conduct Ballast Water Management that at least meets the standard
described in regulation D-2.
6 The requirements of this regulation do not apply to ships that discharge Ballast Water to a
reception facility designed taking into account the Guidelines developed by the
Organization for such facilities.
7 Other methods of Ballast Water Management may also be accepted as alternatives to the
requirements described in paragraphs 1 to 5, provided that such methods ensure at
least the same level of protection to the environment, human health, property or
resources, and are approved in principle by the Committee.
Regulation D-4 Prototype Ballast Water Treatment Technologies
1 For any ship that, prior to the date that the standard in regulation D-2 would otherwise
become effective for it, participates in a programme approved by the Administration
to test and evaluate promising Ballast Water treatment technologies, the standard in
regulation D-2 shall not apply to that ship until five years from the date on which the
ship would otherwise be required to comply with such standard.
2 For any ship that, after the date on which the standard in regulation D-2 has become
effective for it, participates in a programme approved by the Administration, taking
into account Guidelines developed by the Organization, to test and evaluate
promising Ballast Water technologies with the potential to result in treatment
technologies achieving a standard higher than that in regulation D-2, the standard in
regulation D-2 shall cease to apply to that ship for five years from the date of
installation of such technology.
102
3 In establishing and carrying out any programme to test and evaluate promising Ballast
Water technologies, Parties shall:
.1 take into account Guidelines developed by the Organization, and
.2 allow participation only by the minimum number of ships necessary to effectively test
such technologies.
4 Throughout the test and Assessment period, the treatment system must be operated
consistently and as designed.
Regulation D-5 Review of Standards by the Organization
1 At a meeting of the Committee held no later than three years before the earliest effective
date of the standard set forth in regulation D-2, the Committee shall undertake a
review which includes a determination of whether appropriate technologies are
available to achieve the standard, an assessment of the criteria in paragraph 2, and an
assessment of the socio-economic effect(s) specifically in relation to the
developmental needs of developing countries, particularly small island developing
States. The Committee shall also undertake periodic reviews, as appropriate, to
examine the applicable requirements for ships described in regulation B-3.1 as well
as any other aspect of Ballast Water Management addressed in this Annex, including
any Guidelines developed by the Organization.
2 Such reviews of appropriate technologies shall also take into account:
.1 safety considerations relating to the ship and the crew;
.2 environmental acceptability, i.e., not causing more or greater environmental
impacts than they solve;
.3 practicability, i.e., compatibility with ship design and operations;
.4 cost effectiveness, i.e., economics; and
.5 biological effectiveness in terms of removing, or otherwise rendering not viable,
Harmful Aquatic Organisms and Pathogens in Ballast Water.
3 The Committee may form a group or groups to conduct the review(s) described in
paragraph 1. The Committee shall determine the composition, terms of reference and
specific issues to be addressed by any such group formed. Such groups may develop
and recommend proposals for amendment of this Annex for consideration by the
Parties. Only Parties may participate in the formulation of recommendations and
amendment decisions taken by the Committee.
103
4 If, based on the reviews described in this regulation, the Parties decide to adopt
amendments to this Annex, such amendments shall be adopted and enter into force in
accordance with the procedures contained in Article 19 of this Convention.
Article 2 General Obligations
1 Parties undertake to give full and complete effect to the provisions of this Convention and
the Annex thereto in order to prevent, minimize and ultimately eliminate the transfer
of Harmful Aquatic Organisms and Pathogens through the control and management
of ships‘ Ballast Water and Sediments.
2 The Annex forms an integral part of this Convention. Unless expressly provided otherwise,
a reference to this Convention constitutes at the same time a reference to the Annex.
3 Nothing in this Convention shall be interpreted as preventing a Party from taking,
individually or jointly with other Parties, more stringent measures with respect to the
prevention, reduction or elimination of the transfer of Harmful Aquatic Organisms
and Pathogens through the control and management of ships‘ Ballast Water and
Sediments, consistent with international law.
4 Parties shall endeavour to co-operate for the purpose of effective implementation,
compliance and enforcement of this Convention.
5 Parties undertake to encourage the continued development of Ballast Water Management
and standards to prevent, minimize and ultimately eliminate the transfer of Harmful
Aquatic Organisms and Pathogens through the control and management of ships‘
Ballast Water and Sediments.
6 Parties taking action pursuant to this Convention shall endeavour not to impair or damage
their environment, human health, property or resources, or those of other States.
7 Parties should ensure that Ballast Water Management practices used to comply with this
Convention do not cause greater harm than they prevent to their environment, human
health, property or resources, or those of other States.
8 Parties shall encourage ships entitled to fly their flag, and to which this Convention
applies, to avoid, as far as practicable, the uptake of Ballast Water with potentially
Harmful Aquatic Organisms and Pathogens, as well as Sediments that may contain
such organisms, including promoting the adequate implementation of
recommendations developed by the Organization.
9 Parties shall endeavour to co-operate under the auspices of the Organization to address
threats and risks to sensitive, vulnerable or threatened marine ecosystems and
104
biodiversity in areas beyond the limits of national jurisdiction in relation to Ballast
Water Management.
Article 4 Control of the Transfer of Harmful Aquatic Organisms and Pathogens Through
Ships‘ Ballast Water and Sediments
1 Each Party shall require that ships to which this Convention applies and which are entitled
to fly its flag or operating under its authority comply with the requirements set forth
in this Convention, including the applicable standards and requirements in the
Annex, and shall take effective measures to ensure that those ships comply with
those requirements.
2 Each Party shall, with due regard to its particular conditions and capabilities, develop
national policies, strategies or programmes for Ballast Water Management in its
ports and waters under its jurisdiction that accord with, and promote the attainment
of the objectives of this Convention.
Article 5 Sediment Reception Facilities
1 Each Party undertakes to ensure that, in ports and terminals designated by that Party where
cleaning or repair of ballast tanks occurs, adequate facilities are provided for the
reception of Sediments, taking into account the Guidelines developed by the
Organization. Such reception facilities shall operate without causing undue delay to
ships and shall provide for the safe disposal of such Sediments that does not impair
or damage their environment, human health, property or resources or those of other
States.
2 Each Party shall notify the Organization for transmission to the other Parties concerned of
all cases where the facilities provided under paragraph 1 are alleged to be inadequate.
Article 19 Amendments
1 This Convention may be amended by either of the procedures specified in the following
paragraphs.
2 Amendments after consideration within the Organization:
(a) Any Party may propose an amendment to this Convention. A proposed amendment shall
be submitted to the Secretary-General, who shall then circulate it to the Parties and
Members of the Organization at least six months prior to its consideration.
(b) An amendment proposed and circulated as above shall be referred to the Committee for
consideration. Parties, whether or not Members of the Organization, shall be entitled
105
to participate in the proceedings of the Committee for consideration and adoption of
the amendment.
(c) Amendments shall be adopted by a two-thirds majority of the Parties present and voting
in the Committee, on condition that at least one-third of the Parties shall be present at
the time of voting.
(d) Amendments adopted in accordance with subparagraph (c) shall be communicated by the
Secretary-General to the Parties for acceptance.
(e) An amendment shall be deemed to have been accepted in the following circumstances:
(i) An amendment to an article of this Convention shall be deemed to have been accepted on
the date on which two-thirds of the Parties have notified the Secretary-General of
their acceptance of it.
(ii) An amendment to the Annex shall be deemed to have been accepted at the end of twelve
months after the date of adoption or such other date as determined by the Committee.
However, if by that date more than one-third of the Parties notify the SecretaryGeneral that they object to the amendment, it shall be deemed not to have been
accepted.
(f) An amendment shall enter into force under the following conditions:
(i) An amendment to an article of this Convention shall enter into force for those Parties that
have declared that they have accepted it six months after the date on which it is
deemed to have been accepted in accordance with subparagraph (e)(i).
(ii) An amendment to the Annex shall enter into force with respect to all Parties six months
after the date on which it is deemed to have been accepted, except for any Party that
has:
(1) notified its objection to the amendment in accordance with subparagraph (e)(ii) and that
has not withdrawn such objection; or
(2) notified the Secretary-General, prior to the entry into force of such amendment, that the
amendment shall enter into force for it only after a subsequent notification of its
acceptance.
(g) (i) A Party that has notified an objection under subparagraph (f)(ii)(1) may subsequently
notify the Secretary-General that it accepts the amendment. Such amendment shall
enter into force for such Party six months after the date of its notification of
106
acceptance, or the date on which the amendment enters into force, whichever is the
later date.
(ii) If a Party that has made a notification referred to in subparagraph (f)(ii)(2) notifies the
Secretary-General of its acceptance with respect to an amendment, such amendment
shall enter into force for such Party six months after the date of its notification of
acceptance, or the date on which the amendment enters into force, whichever is the
later date.
3 Amendment by a Conference:
(a) Upon the request of a Party concurred in by at least one-third of the Parties, the
Organization shall convene a Conference of Parties to consider amendments to this
Convention.
(b) An amendment adopted by such a Conference by a two-thirds majority of the Parties
present and voting shall be communicated by the Secretary-General to all Parties for
acceptance.
(c) Unless the Conference decides otherwise, the amendment shall be deemed to have been
accepted and shall enter into force in accordance with the procedures specified in
paragraphs 2(e) and (f) respectively.
4 Any Party that has declined to accept an amendment to the Annex shall be treated as a
non-Party only for the purpose of application of that amendment.
5 Any notification under this Article shall be made in writing to the Secretary-General.
6 The Secretary-General shall inform the Parties and Members of the Organization of:
(a) any amendment that enters into force and the date of its entry into force generally and for
each Party; and
(b) any notification made under this Article.
United Nations (UN) Conventions
The United Nation’s Convention on the Law of the Sea (UNCLOS)
The United Nation’s Convention on the Law of the Sea (UNCLOS); Article 196 paragraph 1
provides that:
“States shall take all measures necessary to prevent, reduce and control . . . the intentional or
accidental introduction of species, alien or new, to a particular part of the marine
107
environment, which may cause significant and harmful changes thereto” (UNCLOS,
1982).
United Nation’s Environment Programme (UNEP):
Guiding principle 5: Research and monitoring (UNEP)
In order to develop an adequate knowledge base to address the problem,
States should undertake appropriate research on and monitoring of alien invasive species.
This should document the history of invasions (origin, pathways and time-period),
characteristics of the alien invasive species, ecology of the invasion, and the
associated ecological and economic impacts and how they change over time.
Monitoring is the key to early detection of new alien species. It requires targeted and
general surveys which can benefit from the involvement of local communities.
Convention on Biological Diversity (CBD):
The Convention on Biological Diversity (CBD); Article 8(h) requires Parties:
“As far as possible and appropriate, (to) prevent the introduction of, control or
eradicate those alien species which threaten ecosystems, habitats or species”
(IMO, 2009).
108
Appendix G: GLOSSARY
“Active Substance” means a substance or organism, including a virus or a fungus that has a
general or specific action on or against harmful aquatic organisms and pathogens
(IMO, 2008a).
“Ballast” any solid or liquid weight placed in a ship to increase the draft, to change the trim,
or to regulate the stability (NRC, 1996).
“Ballast tank” a water tight enclosure that may be used to carry liquid ballast (NRC, 1996).
“Ballast Water Management System” means any system which processes ballast water such
that it meets or exceeds the ballast water performance standard. This system includes
ballast water treatment equipment, all associated control equipment, monitoring
equipment and sampling facilities (IMO, 2008b).
“Biodiversity” the variety of different types of organisms living in a given area (NRC,
1996).
“Biological diversity” means the variability among living organisms from all sources
including, inter alia, terrestrial, marine and other aquatic ecosystems and the
ecological complexes of which they are part ; this includes diversity within species,
between species and of ecosystems (United Nations, 1992b).
“Bow” the forward end of a vessel (NRC,1996).
“Copepod” small crustacean of the order Copepoda
“Deballasting” releasing ballast by gravity or pumping from a vessel
“Diatom” microscopic autotrophic organism of the algae class Bacillariophyceae
“Dinoflagellate” microscopic organism of the order Dinoflagellata
“Dispersal vector” mechanism that transports organisms from one region to another (NRC,
1996)
“Estuary” a partially enclosed coastal embayment where fresh water and sea water meet and
mix (NRC, 1996).
“Euryhaline” an organism able to live in an environment of widely varying salinity (NRC,
1996).
“Euryhaline” species are organisms able to tolerate a wide range of salinities (IMO, 2007).
109
“Eurythermal” species are organisms able to tolerate a wide range of temperatures (IMO,
2007).
“General cargo” goods to be transported in a mixture of forms, but usually packaged in some
way other than container boxes (NRC, 1996).
“Non-indigenous species” is any species outside its native range, whether transported
intentionally or accidentally by humans or transported through natural processes
(IMO, 2007).
“In ballast” the condition in which a vessel is operating with ballast and no cargo (NRC,
1996)
“Inoculation” release of an organism in a new environment.
“Introduction” establishment of a reproducing population of an organism in a novel
environment.
“Maritime Dependence Factor” is an index to measure the reliance of a country’s economy
on sea-borne trade.
“Meroplankton” planktonic organisms that spend only part of their life cycles in the
plankton stage and the other as benthic or other forms.
“Nonindigenous” non- native to an area.
“NOBOB” No Ballast On Board
“Phytoplankton” planktonic plants.
“Plankton” otherwise non as drifters because they are that are free-floating or drifting in
water whose movements are determined primarily by water motion.
“Plankton net” fine mesh conical nets dragged in the water to collect plankton during
sampling.
“Port state” a nation in whose port a vessel enters, as contrasted to a flag state, which is the
nation in which the vessel is registered (NRC, 1996).
“Potable” fit for drinking.
“Propagule Pressure” refers to the potential for invasion of a novel environment by nonnative species. This potential is a function of the number and density of species
introduced.
110
“Propeller” revolving screw like device used for propelling ships through water (NRC,
1996).
“Protists” eukaryotic organisms comprised of a single cell (NRC,1996).
“Reballast” to load water ballast back on a vessel after deballasting (NRC, 1996).
“Red tide” refers to massive dinoflagellates blooms where the water changes colour and
toxic.
“Salinity” amount of salt dissolved in water.
“Sea chest” an enclosure attached to the inside of the shell plating and open to the sea,
providing the connection of a piping system to overboard (NRC,1996).
“Slamming” heavy impact resulting from a vessel’s bottom near the bow making sudden
contact with the sea surface after having risen above the surface due to relative
motion (NRC, 1996).
“Stability” the condition to which a body will move back to a condition of equilibrium when
given a small initial movement away from this condition (NRC, 1996).
“Stern” the after end of a ship
“Strain” deformation resulting from stress on a body (NRC, 1996).
“Stress” force per unit section area producing deformation in a body (NRC, 1996).
“Tanker” a cargo vessel designed for carriage of liquid cargo in bulk.
“Tens Rule” states that in the event of a bio-invasion, only 10% of invading species become
introduced, only 10% of those introduced become established and only 10% of those
established become invasive.
“Trim” the difference between the drafts: the after draft minus the forward draft (NRC,
1996).
“Turbidity” amount of light-reflecting material in suspension in water.
“Zooplankton” planktonic animals.
111

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