The oceans are exploited for salts and oils, while coastal regions are exploited for their reefs and for tourism activities. This is leading to exploitation of ocean resources and as a result they are constantly under threat from overutilization.
Aquatic ecosystems are home to rare species. Excessive fishing in and around aquatic ecosystems is disrupting the natural food cycle as well as causing fish species like Bluefin Tuna, Vaquita and the Mexican Walking Fish to become nearly extinct.
3. Oil spills:
The continuous oil exploration on the seas leads to spillage of oil on the waters. As oil is lighter than water, it spreads over the surface of the seawater, as a result of which supply of oxygen to the marine environment gets stopped. For miles, seawater becomes unsuitable for sea animals and birds. Oil blocks the respiratory organs of fish and other sea animals. Many oceanic species are disappearing because of oil spills.
4. Destruction of habitat:
The natural habitats for numerous aqua-marine species are being disturbed. This is leading to a threat of existence for species of fishes, frogs and reptiles. With more and more industries being set up near oceans, the natural habitat is being spoilt.
5. Nuclear wastes:
With the establishment of more nuclear power plants and laboratories for scientific research, nuclear wastes that are released into the oceans every year are rising. Such dumping of radioactive waste into the oceans is harming ocean environments.
6. Reclamation of land:
As population rises and urban areas expand, the need for more space arises. While cities and towns are moving towards the forests on the one side, they are moving to the coastal lines on the other. Shore regions are being reclaimed to turn them into residential as well as office areas. This is also affecting the existing marine life.
7. Extensive tourism:
Tourism is supposed to help develop regions that are remote but beautiful. But haphazard tourism in many areas, particularly on the sea shores, is resulting in rare ecosystems being destroyed. Scuba diving, fishing and boating activities turn these ecosystems into garbage bins.
As the vegetation cover on land decreases, more soil along with nutrients flows off with rainwater into streams and rivers and finally reaches the oceans. When these nutrients are released into the sea, they promote growth of algae, which harms aquatic ecosystems. This process is termed as eutrophication.