Question

Which among the following improves soil fertility and plant growth without causing water pollution?

• A. Azotobacter
• B. Potassium nitrate
• C. Ammonium sulphate
• D. Superphosphate

Answer 1

The correct option is A Azotobacter

$\bullet$ Biofertilisers are micro-organisms used in order to add up the nutrients and help to build up the fertility of the soil without causing water pollution. Among the given options, Azotobacter is a biofertiliser that helps to increase the nitrogen level in the soil.
$\bullet$ Ammonium sulphate, superphosphate and potassium nitrate are examples of chemical fertilisers. Excessive use of these can lead to soil infertility and environmental pollution. Water pollution results from runoff of these chemicals into surface waters or from infiltration of these chemicals into groundwater.