Question

what organic matter discharge into water bodies uses up substantial dissolve in water

Answer 1

Organic material discharged in water cause a fertility increase which promotes algal blooms.
The excess algae consumes oxygen in water , which result in oxygen depletion and dead zone where fish and other water creatures cannot suvvive

Answer 2

An algal bloom in the water bodies use all the substantial dissolved in water.

Explanation:

When water is rich in organic matter , it promotes the growth of algae in it . When algae grow in large amount, it uses all the oxygen present in the water body. Due to which the animals living in that habitat will face oxygen shortage as the cover of algae on the water surface will prohibit the exchange of gases between atmosphere and water body .

Thus the presence of excess organic matter in water will have adverse effect on the life present in it.

This process is called Eutrophication.