Today the coastal areas of the world are intensively used. They supply the bulk of the world’s wild-caught fish. In fact, 90 per cent of global fishery takes place in coastal waters. Another use of great economic significance is the drilling of natural gas and oil in coastal areas.In the past few years, coastal waters have become increasingly attractive sites for the harnessing of wind energy to generate electricity. Another resource supplied by coasts are mineral raw materials, particularly sand and gravel, which are used in concrete manufacturing, as filling sand on building sites, or for hydraulic filling to create new port or industrial sites on the coast. In many places, human use of the coasts is exceeding their carrying capacity. The sources of pressure on these habitats are multifarious. High levels of nutrients are discharged into the sea from untreated effluents, from intensively fertilized agricultural lands or from aquaculture. This leads to eutrophication and to severe algal blooms. Pollutants from industrial processes that seep into coastal waters also pose a threat. These include heavy-metal compounds or persistent chemical substances that accumulate in the food chain and can give rise to illnesses like cancer. 

Added to these problems caused locally or regionally by human activities in coastal areas are those which are driven by the global phenomenon of climate change: ocean warming, ocean acidification and sea-level rise. How severely these consequences of climate change will affect coastal habitats depends to a great extent on how much carbon dioxide (CO2) is released into the Earth’s atmosphere in future.Besides this, coasts are exposed to natural hazards such as earthquakes, landslides or tsunamis

World Ocean Review 2017