Nitrification

when animals and plants die, the proteins in them are converted into ammonium compounds by the putrefying bacteria and fungi (decorposers) found in the soil. this process is called as amonification we can define ammonification as conversation of complex organic compounds like proteins into ammonia.

ammonium salt in the soil s converted into nitrites by nitrosomanas bacteria. the nitrites are then converted into nitrates by nitrobacter bacteria. these bacteria are called nitrifying bacteria. the nitrates, so formed in the soil, can once again be absorbed by the plants. this process Is called nitrification so, the conversion of ammonia into nitrates are called nitrification.

some of the nitrates are absorbed by the plants. rest of the nitrates in the soil are converted by pseudomonas bacteria into nitrogen gas which escapes into the atmosphere. the conversation of nitrates into free nitrogen gas by denitrifying bacteri (Pseudomonas) is called denitrification

Thus, the nitrogen cycle maintains the percentage of the nitrogen present in the atmosphere more or less constant.