Oceanic "dead zones" why more and more?

Dead zone "refers to the ocean is almost without oxygen. There, the vast majority of sea creatures can't survive.

A recent issue of science, published a research report pointed out that climate change caused by using fossil fuels, is leading to ocean temperatures rise. And the higher the temperature, the lower the oxygen content. Fertilisers and sewage from the land into the sea, also appeared many "dead zones" along the coastal area. According to statistics, since 1950, nearly oxygen-free "dead zone" in the ocean area has increased by three times, the number of Marine dead zones along the coast of the from of less than 50, 1950 to the present at least 500. Ocean's overall oxygen also continued to decline, has decreased by 2%, equivalent to 77 billion tons of oxygen. Long, this can provoke the Marine biological extinction, brought hundreds of millions of people have lived on the sea.

The sea is more than 500 million people of the world's food sources, and provide jobs for 350 million people. According to the report, the water of the sea lack of oxygen, can affect the growth and reproduction of Marine organisms, and make them more susceptible.

Marine oxygen reduction, could also exacerbate climate warming. Survival of Marine microorganisms in hypoxia environment will produce a large number of nitrous oxide, a greenhouse gas carbon dioxide, the intensity is about 300 times.

【返回列表】