Water Pollution and its Control

A factory drains its waste water into the nearby lake. It has caused algal bloom. The phenomenon responsible for its cause is:

Drinking mineral water with very low level of pesticides (0.02ppm) for long periods may

Biological Oxygen Demand (BOD) is a measure of

Which of the following is biodegradable pollutant?

Which method in sewage treatment, removes suspended solids? Is it primary treatment or secondary treatment?

A river with an inflow of domestic sewage rich in organic waste may result in death of fish due to lack of oxygen.

Algal blooms make water unfit for human consumption but cause the enormous growth of fish. 

Which ONE of the following can NOT cause eutrophication of lakes?

The maximum concentration of harmful chemicals is expected to be found in organisms

The biomagnification of which pollutant causes a decline in the bird population?

A food chain in a polluted aquatic ecosystem is given. Observe it and answer the following question.

Fresh water → Algae → Fishes → Birds.

This ecosystem will be destroyed gradually due to biomagnification because

A food chain in a polluted aquatic ecosystem is given. Observe it and answer the question.

Freshwater → Algae → Fishes → Birds.

Which organisms are disturbed more due to biomagnification?

The sewage water decreases the biological oxygen demand.

Water prevention and control of pollution act was implemented in the year of

The term used for the excessive growth of algae, plants and animals in water bodies due to the nutrient enrichment particularly with nitrogen and phosphorus is

The electric power plants cause _____(thermal/air/noise) pollution.

DDT and mercury undergo biomagnification in the food chains.

In the treatment of waste water discharge, which treatment stage involves biological treatment?