3.
Draw a diagram to show the nitrogen cycle
and explain the process of nitrification and
denitrification.
Answers
Answer:
It is there in std 9 text book its briefly explain ✌️✌️✌️
Explanation:
Nitrification
The conversion of ammonium to nitrate is performed primarily by soil-living bacteria and other nitrifying bacteria. In the primary stage of nitrification, the oxidation of ammonium (NH+
4) is performed by bacteria such as the Nitrosomonas species, which converts ammonia to nitrites (NO−
2). Other bacterial species such as Nitrobacter, are responsible for the oxidation of the nitrites (NO−
2) into nitrates (NO−
3). It is important for the ammonia (NH
3) to be converted to nitrates or nitrites because ammonia gas is toxic to plants.
Denitrification
Denitrification is the reduction of nitrates back into nitrogen gas (N2), completing the nitrogen cycle. This process is performed by bacterial species such as Pseudomonas and Paracoccus, under anaerobic conditions. They use the nitrate as an electron acceptor in the place of oxygen during respiration. These facultatively (meaning optionally) anaerobic bacteria can also live in aerobic conditions. Denitrification happens in anaerobic conditions e.g. waterlogged soils. The denitrifying bacteria use nitrates in the soil to carry out respiration and consequently produce nitrogen gas, which is inert and unavailable to plants.
