Question

Question 26 Why are non-point sources of water pollution harder to control then point sources? Give an example of a point source and an example of a non-point source of water pollution.  Describe with details how the dead zone in the Gulf of Mexico forms. .

Answer 1

Point source of pollution means that the pollution is caused by a single source or a single source is responsible for the pollution.

Non-point source means that the pollution is not cause by a single point,which means there are multiple sources of pollution.

So it is harder to find out the sources and then controllig the pollution in case of non-point sources of water pollution than the point sources water pollution

Now in case of the dead zone in the Gulf of Mexico evry summer marine life starts to die,the reason is far away from the ocean due to non-point source because the agricultural land on the side of the Mississippi river fertilizer rich water flows to the river water and when this fertilizer filled river water reaches the ocean sudden algea bloom occurs and then die and sink into the bottom of the ocean and then this algea is naturally digested by the bacteria and the bacteria uses oxygen during the digestion of the algea,so the sea water runs out of dissolved oxygen and the marine life dies without oxygen,This is the cause of the dead zone in the Gulf of Mexico.