Question

A lake which is rich in organic waste may result in 

(a) increased population of aquatic organisms due to minerals

(b) drying of the lake due to algal bloom

(c) increased population of fish due to lots of nutrients

(d) mortality of fish due to lack of oxygen

Answer 1

Correct option (d) mortality of fish due to lack of oxygen

Explanation

Umen much of organic matter is present in lake, lots of microbial activity takes place ln 1ts decomposition process. So, demand for oxygen increases. This increased O₂ demand depletes the dissolved oxygen in water at faster rates. This adversely affects the living conditions for other organisms like fishes, etc. ultimately causing their death.