The ocean still remains as one of the important natural resource capital of many nations. The numerous benefits (food, climate regulation, nutrients recycling, etc) particularly the quality of life derived from marine and coastal areas have raised global concern for the adoption of sustainable strategies that will ensure the existence of marine and coastal areas in its natural state with less impact caused by externalities.
The natural structure and function of coastal marine ecosystems are faced with a lot of environmental and ecological challenges.
The key issues of coastal marine systems sustainability are discussed below.
Coastal Marine Environmental Degradation
The degree of pollutions is of a greater concern when considering sustainability issues of coastal marine systems. Land-based activities such as agriculture and industries remains the major source of coastal pollution.
Untreated sewage, fertilizer run-off, pesticides, marine transport, plant emissions and industrial effluent contributes to the high nutrient pollution in the ocean causing many lost of habitats in the ocean and water quality. Dumping of waste at sea is still a common practice in coastal regions particularly in developing countries. Two million tons of agricultural, industrial and sewage waste are discharged into the world’s water daily (UN WWAP, 2003). Developing countries account for 70% of industrial untreated wastes disposed into waters which consequently flows into the sea (UN-Water, 2009).
Mechanisation and construction activities involved in the extraction of oil and gas in oceans, mining of other minerals and coastal tourism in fulfilment of economic growth policies by governments posses a threat of coastal pollution.
Unsustainable Marine Resource
Population growth in marine regions and high investment in fishing method has resulted in overexploitation of fish for food and income to meet investment cost. According to the Food and Agriculture Organization of the United Nations, fish stocks overexploited, depleted or those recovering from depletion accounted for about 28 percent in 2007. For instance Taiwan experienced a decline in offshore and coastal fisheries from 370.9 thousand tons in 1990 to 135.4 thousand tons in 2007 (Liu, 2012).
Countries in Asia and West Africa suffer from unsustainable fishing due to illegals fishing lack of monitoring systems among others. The benefits lost to fishing nations amounts to $50 billion per annum (UNCD, 2012). Among such benefits include income from source of employment it creates and food which is the main source protein for coastal communities, drugs tourism and so on.
Minerals located in and around the ocean are also at risk of being depleted as a result of the invasion of more sophisticated technologies.
Ecological and Biodiversity Health
Population growth in coastal regions coupled with urbanisation and industrialization has resulted to land reclamation for developing new cities, construction of habours and...