Nitrogen in atmosphere(N2) Plants Assimilation Denitrifying bacteria Nitrogen-fixing Nitrates bacteria in root (No3) nodules of Decomposers(aerobic legumes and anaerobic bacteria and fungi) Nitrifying Ammonification bacteria Nitrification Ammonium(NH : e3). Nitrites( No2) Nitrogen-fixing soil bacteria Nitrifying bacteria Microbes in nitrogen cycleMicrobes in nitrogen cycle