why the quality of ocean water is decreasing?

Answer 1

Because the rivers that carry water to the sea themselves are polluted and this polluted water is added to the sea.Secondly the remains of dead sea animlas and the sea plant debris accumulate in course of time leading to the deterioting condition of the water in the oceans.During evaporation, only pure water is evaporated continuously,leaving behind the waste products in the ocean itself.

Answer 2

It is a result of simple mathematics. If you look at what is going in, what is going out and what is happening in between' you see that:
1. More and more pollution is being discharged into the sea all over the world. This means there is more work for the marine ecosystem to degrade this stuff.
2. Overfishing, and also pollution kill or extract from the sea many species, some of which have an important role in cleaning up the ocean. So the ocean can process/clean less and less as we exploit it.
3. As somebody said, evaporation takes up clean water (mostly) leaving all the pollution behind.

In short, we overload the system while at the same time taking out important pieces in the marine environment. So it has to do more with less. The end result is obvious and answers your question.

Answer 3

evaporation of d water increses day 2 day
half of d sea is filled with waste products which pollutes it n also cause harmful 2 ur health

Answer 4

sewage, chemical, rubbish dumping (sometimes illegaly)

polution

Dead degrading matter like Big whales/fish/ some times even humans

oil spills

Answer 5

pollution