QuestionEnvironment / thermal pollution
Thermal pollution which involves release of excessive amounts of heated water in aquatic systems is harmful. It is because hot water:
- (a) kills aquatic plants.
- (b) causes oxygen starvation.
- (c) kills aquatic microbes.
- (d) causes CO₂ depletion.
Answer: (b) causes oxygen starvation.
Solubility of O₂ falls as water temperature rises, while metabolic rate of aquatic animals rises. Result: oxygen starvation (low DO), fish kills. Heat may harm plants and microbes too, but the basic harm is loss of dissolved oxygen.