5.3.2. Effects of Water Pollution

1. Effects on aquatic ecosystem:

i ) Polluted water reduces Dissolved Oxygen (DO) content, thereby, eliminates sensitive organisms like plankton, molluscs and fish etc.

However a few tolerant species like Tubifex (annelid worm) and some insect larvae may survive in highly polluted water with low DO content. Such species are recognised as indicator species for polluted water.

i i) Biocides, polychlorinated biphenyls (PCBs) and heavy metals directly eliminate sensitive aquatic organisms.

i ii) Hot waters discharged from industries, when added to water bodies, lowers its DO content.