chidi ibe

The Guinea Current Large Marine Ecosystem extending from Guinea Bissau to Angola and covering sixteen countries in West and Central Africa and characterized by distinctive bathymetry, hydrography, chemistry, and trophodynamics with the Guinea Current as the unifying feature has remained a sources of global interest. With openness to the Atlantic Ocean and watercourses with access to the sea such as the Congo and Niger Rivers, the GCLME embodies some of the major coastal upwelling sub-ecosystems of the world and is an important center of marine biodiversity and marine food production ranked among the most productive coastal and offshore waters in the world. However, pollution from domestic and industry sources, over-exploitation of fisheries and poorly planned and managed coastal developments and near-shore activities are resulting in a rapid degradation of vulnerable coastal and offshore habitats and shared living marine resources of the GCLME putting the economies and health of the populace at risk. The deterioration in water quality (chronic and catastrophic) from land and sea-based activities (especially industrial, agricultural, urban and domestic sewage run-off and mining activities including the oil and gas sector), eutrophication and harmful algal blooms have been identified as a major transboundary environmental problem by the countries in the adopted Transboundary Diagnostic Analysis (TDA). Arising from the results of the various environmental and socio-economic studies and assessments conducted over the years as documented in the Transboundary Diagnostic Analysis (TDA), the countries resolved to adopt a holistic, multi-sectoral and regional approach embodied in the large marine ecosystem concept for transboundary pollution management in the region. The agreed management actions to be undertaken jointly by the sixteen countries are encapsulated in the adopted Strategic Action Programme to be implemented by the Interim Guinea Current Commission (and later the Guinea Current Commission), established by the countries as an intergovernmental consultation and coordination body, with the technical assistance and co-funding of the Global Environment Facility (GEF), the United Nations Industrial Development Organization (UNIDO), United Nations Development Programme (UNDP) and United Nations Environment Programme (UNEP).

Analyses of recent carbonate sediments of a wide variety of textural types reveal organic carbon content of 0.98–5.23 wt.% which are well above the 0.3 wt.% minimum requirement for carbonate sediments to be considered potential source deposits.The organic facies consist dominantly of autochthonous marine organic matter, both particulate and dissolved, which is highly pyrolysis-degradable. Under the correct conditions of burial, temperature and probably catalysis (despite the general absence of clays), commercially-significant hydrocarbons would be generated and would accumulate as petroleum in those rocks that possess the necessary effective porosity.This concept of the origin of petroleum in carbonate rocks affords an explanation for the exceptionally rich petroleum accumulations in porous carbonate rocks; it is also consistent with the stratigraphic habitats of most hydrocarbon pools in carbonate petroliferous provinces.

This study is a first step towards valuing the Guinea Current Large Marine Ecosystem (GCLME), one of the five world's most productive marine areas that are rich in fishery resources, petroleum production, and an important global region of marine biological diversity. The area is highly degraded and thus demands urgent attention to recover and sustain depleted fisheries; restore degraded habitats; and reduce land and ship-based pollutions. Achieving this goal would be a mirage if the actual value of the ecosystem's contribution to the society is not known. Valuation can help identify the main beneficiaries of conservation and the magnitude of benefits they receive, and help design measures to capture some of these benefits and contribute to financing of conservation. Hence this study used the direct output approach to estimate the value of relevant marine activities in the area. The result shows that the total value of output in GCLME when some outputs namely, marine fishery, offshore oil production, NTFP (periwinkle) and mining, are considered as $49,941.4 million. Among these uses, offshore oil production has the highest value accounting for 59.79% of the total estimate. These estimates provides sufficient evidence to show that GCLME provide enormous value and should be managed appropriately to sustain the gains if the economic development would be guaranteed especially considering that most countries in the GCLM depend on natural resources for their survival. Evolving a well defined property rights regime and an efficient governance system for management is recommended.

The Gulf of Guinea is situated in the narrow protrusion of eastern Equatorial Atlantic between latitudes 2°S and 5°N and longitudes 8°W to 12°E, spanning a coastline length of approximately 130 nautical miles. The dominant feature of this shallow ocean off the coast of countries in Western Africa is the Guinea Current. The distinctive bathymetry, hydrography, productivity and trophodynamics of this shallow ocean qualify it as a large marine ecosystem (LME) and is indeed recognized as the number 28 of the 64 delineated LMEs globally. This area is one of the world’s productive marine areas that is rich in fishery resources, oil and gas reserves, precious minerals and an important global reservoir of marine biological diversity. Unfortunately, pollution from residential and industrial sources has affected the waters of the Gulf of Guinea resulting in habitat degradation, loss of biological diversity and productivity, and degenerating human health. In reversing this trend of marine environmental degradation, the countries of the region adopted an integrated and holistic approach using the LME concept to sustainably manage the environmental and living resources of the region. The concept is predicated on the fact that marine environmental pollution and living resources respect no political or geographical boundaries and so require a holistic and regional approach for its management. The Gulf of Guinea countries through the Global Environment facility funded regional/communal project on water pollution control and biodiversity conservation achieved a paradigm shift in living resources and environmental management in the region using the LME concept.

Published data from an organic geochemical study of Recent oolites from the Bahamas and teh kPersian Gulf suggest that petroleum-bearing oolites may be the source, as well as the reservoir, of the hydrocarbons they contain. This paper advances a scheme for the generation of leached oolites with oomodic porosity, petroleum-bearing oolites could be viewed as integrated source-resrvoir rocks.

In Part I, (Journ. Petrol. Geol. 7 (3) 267–276) a scheme for the in situ generation and accumulation of hydrocarbons was presented. It was concluded that the indigenous origin of petroleum in oolites, which preculdes a long and wasteful primary migration process, affords another explanation for the exceptionally rich petroleum accumulations which characterise oolite reservoirs. The present paper now tests the validity of that proposal by a selected case study.For an unequivocal discussion of an oolite reservoir productive of petroleum generated in situ, it would be necessary to describe in some detail those formations either underlying, overlying or lateral to the formation of interest which, because of their hydrocarbon content in the general region, might perhaps be supposed to have been the original source of the petroleum now found in the oolites. such an account would be more detailed than space permits. The need arises, therefore, for the selection of an example which allows the least number of alternative possibilities. This was the guiding principle behind the choice of the prolific Arab Formation (Upper Jurassic) of Saudi Arabia as a case study (Fig. 1)

The Guinea Current Large Marine Ecosystem (GCLME) extending from Bissagos Island (Guinea Bissau) in the north to Cabinda (Angola) in the south defines the shared transboundary waters off the coast of western Africa, which embodies some of the major coastal upwelling sub-ecosystems of the world and is an important centre of marine biodiversity and marine food production. The GCLME is characterized by distinctive bathymetry, hydrography, chemistry, and trophodynamics and represents the number 28 Large Marine Ecosystem (LME) ranked among the most productive coastal and offshore waters in the world with rich fishery resources. However, over-exploitation of fisheries, pollution from domestic and industry sources, habitat destruction and poorly planned and managed coastal developments and near-shore activities are resulting in a rapid depletion of the rich fisheries resources and degradation of vulnerable coastal and offshore habitats putting the economies, productivity and health of the populace at risk. Recognizing the urgency of the fisheries decline and the environmental and socio-economic consequences for the region, the 16 countries bordering the ecosystem have mobilized complementary resources to the funding from the Global Environment Facility and United Nations Industrial Development Organization to implement priority management actions agreed in the preliminary Strategic Action Programme for the recovery of depleted fish stocks and restoration of degraded habitats for the advancement of the achievement of the World Summit on Sustainable Development (WSSD) Johannesburg Plan of Implementation targets for recovery of fish stocks.

A fundamental requirement in collaborative monitoring programmes in marine pollution studies is the intercomparability of data obtained from participating laboratories irrespective of the country of origin. This demands that the data be ‘true’. The production of ‘true’ data requires that laboratories adopt good field and laboratory procedures as part and parcel of a Quality Assurance/Quality Control (QA/QC) regime. This includes the selection of internationally-validated methodologies for sampling and analysis, mandatory use of reference materials (certified reference materials, whenever possible) and participation in ‘blind’ international intercomparison exercises. Under the IOC/UNEP/IMO Programme of Global Investigation of Pollution in the Marine Environment (GIPME) and its operational, regionally-based Marine Pollution Monitoring System (MARPOLMON), the steadfast pursuit of data of appropriate quality from participating laboratories in different regions of the world ocean is underpinned by the activities of the three GIPME Groups of Experts—on Methods, Standards and Intercalibration (GEMSI); on Effects of Pollutants (GEEP); and on Standards and Reference Materials (GESREM) which is additionally co-sponsored by IAEA. Experience gained by these groups over the years qualify GIPME as a credible mechanism for the generation of precise and accurate data upon which global, regional and national regulatory actions for the protection of the coastal and marine environment can be based.

Recent oolites from the Bahama Banks are shown to contain 1.23–4.13 wt% organic carbon of algal origin, chiefly in the form of proto-kerogen. Characterization of the ogranic matter by routine optical and chemical means revealed that, although it is immature, it has a very high potential for generating petroleum hydrocarbons.It is suggested that with rise in temperature due to burial, and perhaps to catalytic influence of the host sediments, this proto-kerogen of algal-amorphous facies would, through time, generate significant amounts of hydrocarbons. In those oolite deposits with adequate porosity, the hydrocarbons could accumulate as petroleum.

Environmental pollution in the Gulf of Guinea (GOG) coastal zone has caused eutrophication and oxygen depletion in the lagoon systems, particularly around the urban centres, resulting in decreased fish (reproduction) levels and waterborne diseases. A pollution sources assessment was undertaken by six countries in the region as a first step in defining a region-wide Environmental Management Plan. Results show that households produce 90% of solid waste. Industry, however, is responsible for substantial amounts of hazardous waste, specifically the Nigerian petroleum industry. The latter is also responsible for the spilling of large amounts of oil. BOD load from industrial effluents is slightly larger than domestic loads in the industrialised coastal zone. Wastewater treatment systems are either absent or inadequate. Apart from large-scale gas flaring in Nigeria, air pollution, in terms of and SO2 emissions, is contributed mainly by traffic. Particulates, originate mainly from industries and domestic biomass burning.