1, denitrification is carried out in soil. Denitrification refers to the process of reducing nitrate and nitrite to gaseous nitrogen and nitrogen by microorganisms under anoxic conditions. The return of active nitrogen to the atmosphere in the form of nitrogen is the main biological process. There are 24 characteristics of microorganisms that can remove nitrogen in soil. Most denitrifying bacteria are heterotrophic bacteria, and a few autotrophic bacteria such as Thiobacillus denitrificans.

2. In rivers, lakes and seas. The conditions of denitrification are: denitrifying microorganisms. Suitable electron donors such as organic carbides and reduced sulfides. Anaerobic conditions. Nitrogen oxides.