Whether placement of nitrogen fertilizer below the layer of crop residue will reduce nitrogenimmobilization is not clear.
对于把氮肥施在植物残体覆盖层以下是否会减少氮的固定，这个问题目前尚不清楚。
2
The nitrogen mineralization - immobilization turnover(MIT) process in soil is closely connected with the capacity of nitrogen supply to plant and the loss of nitrogen to environment .
土壤氮矿化-固持周转（MIT）过程与土壤供氮力及氮素损失间存在密切关系。
3
Methods Porous ceramics were used as immobilization carrier. Optimum conditions for nitrate-nitrogen removal of downflow fixed-bed bioreactor were studied.