Environmental pollution occurs in cases where contaminants are introduced into the environment. In most cases, pollution is often man made. This imply that anthropogenic activities often occur due to exploration for resources. Pollutants originate from a number of sources resulting in different kinds of hazards. Such hazards may contaminate the soil, water and air quality. In whichever way pollution may occur, the impact is always more on environmental resources. Usually, where pollution occurs, it affects habitats thereby lowering survival of various forms of life. This trend leads to loss of biodiversity. Biodiversity is the availability of various specie organisms such as plants, animals, microorganisms and by extension, all animate things present in any ecosystem (Australian Museum, 2015).1. Marine biodiversity on the other hand connotes various specie organisms found in fresh water bodies, estuaries, swamps, mangroves, oceans as the case may be. Due to high level pollution, loss of biodiversity is acute in marine life within the Niger Delta of Nigeria.
Marine life simply put is all living things found within the water environment (oceans and seas). Marine life requires a healthy water body for the flourishing of various forms of lives. Living things found within it and near coastal areas consist of highly valuable and diverse species. The richness of this marine life has survived centuries of exploration activities seeing people fishing from it as well as deriving other forms of livelihoods from it. Marine resources such as sea food over the years have predominantly serve as major sources of protein to coastal communities in the Niger Delta. Apart from this, marine resources have supplemented as sources of income for fishing communities who depend exclusively on such items for local economy. Various forms of marine life such as plants, animals and organisms that live in the salt water of the sea or ocean, or the brackish water of coastal estuaries (http://en.wikipedia.org/wiki/Marine_life)2 are always the first target of destruction in any case of marine pollution.
Characterization of marine life
Marine life basically can best be characterized into any of the following three species:
Benthos are organisms that live in and on the bottom of the ocean floor. They include worms, clams, crabs, lobsters, sponges and other tiny organisms that live in the bottom sediments (Woke, 2015)3. Nektons are swimming animals such as fishes that move independently of water currents. Planktons are small floating organisms that are carried along by the currents. Examples are phytoplankton (plant-like) and zooplankton (animal-like). Common causes of pollution in the Niger Delta marine environment include plastics, industrial wastes, oil spills etc.
The largest factor affecting the oceans is plastic wastes disposal directly into ocean bodies (www.alternet.org/environment/how-ocean-pollution-impacts-marine-life-and-all-of-us)4, of which 80 per cent of marine debris is plastic. Discarded plastic bags, six pack rings and other forms of plastic waste which often finish up in the ocean present danger to aquatic life. Aquatic life can be threatened through entanglement, suffocation and ingestion. Plastics present a major hazard to seabird, fish and other marine creatures. For example, plastic fishing lines and other debris can strangle and choke fish. (This is sometimes called ghost fishing). Sea creatures that are killed by plastics readily decompose but the plastic does not. It remains in the ecosystem to kill again and again (Woke, 2015). Over the last decade, we have produced more plastic than we have in the last 100 years. This sharp increase in plastic entering our waters harm not only marine life but also humanity.
One of the sources of damage to coastal living resources is thermal pollution. Industries and factories discharge effluents and hot water into the sea; this is causing thermal pollution. Heat is an important form of energy that impacts on the aquatic environment. The waste heat often gets released into the aquatic environment leading to a term called thermal pollution. Rampant discharge of hot effluents into coastal environment is quite common off the coasts of major industrialized towns of the Niger Delta region such as Warri and Port Harcourt. When the temperature of the water changes, metabolism of marine animals are inadvertently altered. Thermal pollution also causes mass fish kills and forced migration of fish species to other regions.
Oil spill is a major contributor to environmental pollution in the Niger Delta. Oil can be spilled on the water body through exploration activities, engines of sea vehicles, inadequate equipment and accidents. Crude oil lasts for years on the sea and is extremely toxic to marine life. Ingestion of oil causes dehydration and impaired digestion (G.N.Woke, 2015) in marine organisms. Oil spilled in the ocean could get to the gills of marine organisms, causing difficulty in their respiration. Oil spills into ocean bodies may hamper such important activities from taking place. More so, it may prevent sunlight from reaching the marine plants as it floats on the surface of the water and alters photosynthesis.
Ship can also pollute waterways and oceans in many ways, also creating noise pollution that disturbs natural wildlife. Pollution reduces the amount of oxygen in the ocean. It also increases the biological oxygen demand and as a result, marine organisms like crustaceans and other seafood reducing their abundance in the Niger Delta. Most of those species are becoming endangered and may be on their way to extinction. Plastic debris could possibly cause the deaths of up to a million seabirds every year. The impact of environmental pollution in the Niger Delta is not only seen on marine life alone but on people as well in terms of loss of livelihoods. Most people are predominantly fisher men so diminishing fish content in the region is resulting in high cost of living for those dependent on such means of livelihood. The protein from fishes and other seafood can no longer be sourced easily since seafood is disappearing. Apart from the direct impact on living resources, marine pollutants tend to adversely alter or degrade the environment to extreme conditions that are beyond the tolerant or adaptation limits of the living resources therein.
Marine pollution is totally unavoidable due to global population explosion and technological innovations by man. However, it was asserted that the problem could be minimized through careful management (Elenwo and Akankali, 2015)6.
To solve this overwhelming issue in the Niger Delta, effort must be put in place by authorities, individuals and industries to mitigate the effect of pollution in the region. That will require both social and political will together with a shift in awareness so more people respect the environment and are less disposed to abusing it. At an operational level, regulations must be put in place to mitigate impact of marine pollution. Secondly, there is need for international cooperation by various trans national governments in marine sanitation and control of sea disposal. Environmental laws should be enacted and the marine environment should not be left out, to prevent further damage, as environmental laws will make it tougher for people to pollute the marine environment (Woke, 2015). Balanced information on the sources and harmful effects of marine pollution need to become part of general public awareness as a way of reducing impact.
On the part of communities around the near coast areas, there is need for adequate sensitization on how they can be mindful of their activities. They should be taught on how to go about their fishing activities in a sustainable manner. The use of chemicals for fishing should also be discouraged as all these will help conserve fish species. Industries should also be mindful of their activities. There should be a law banning industries from disposing directly into water bodies; rather they should encourage reduce, reuse, and recycling of wastes to curb marine pollution.
Most importantly, efforts need to be put in place to clean up the affected environment to restore it to a more favourable state for marine organisms to thrive. Other measures recommended to the government and other agencies include: aggressive enlightenment and sensitization in coastal communities, economic empowerment of residents of coastal communities, strict enforcement of relevant laws concerning the abuse of the seas and setting up scientific committees which will collaborate with such international committees to solve localized problems in the affected areas.
1 Australian Museum (2015). What is Biodiversity? Retrieved from https://australianmuseum.net.au/what-is-biodiversity1.
2 Woke, G.N.(2015). Hydrobiology
5 Elenwo, E.I. and Akankali, J.A. (2015). The effects of marine pollution on Nigerian. Coastal resources. Journal of Sustainable Development Studies
7 https://oceanservice.noaa.gov/facts/pollution.what-is-the-biggest-source-of-pollution-in-the-ocean? (2015-11-22)
8 www.bluevoices.org/the-effects-of-ocean-pollution-on-marine-mammals- Bob Bohle