摘要
在小麦盆栽试验后的１５Ｎ标记土壤上，研究了水稻生长过程中土壤微生物量Ｃ、Ｎ和土壤固定态铵的变化及其有机无机肥料残留Ｎ的有效性。结果表明，土壤微生物量Ｃ随着水稻生长而逐渐增加，到收获时达到１３７８．６～１７９０．５ｍｇ／ｋｇ土；土壤微生物量Ｎ的变化与水稻吸收Ｎ素有关，开始时由于淹水使得土壤微生物量Ｎ有所下降，但随后又有所增加；随着水稻对Ｎ的吸收增加，生物量Ｎ又下降，直到水稻成熟期又有所恢复。在整个水稻生长季节中，土壤固定态铵的含量变化不大，但其中的一些１５Ｎ仍与外界土壤中矿质Ｎ发生了交换，表明这些固定态铵对水稻仍有较高的有效性。
Pot experiments were carried out on the 15N-lablled soil after winter wheat to study the changes of soil microbial biomass C,N and soil fixed ammonium during rice growth. The results showed that soil microbial biomass C increased with the rice growing and reached the highest at the harvesting stage.The soil microbial biomass N decreased a little bit at the beginning of experiment and then rose to the highest at the tillering stage, after which it decreased again with the increase of N absorption by rice. The content of soil fixed ammonium changed little during the rice growing, but some of the 15N fixed by soil clay minerals exchanged with the soil mineral N, showing that the fixed ammonium in last crop was also effective to rice at the second cropping.
出处
《土壤学报》
CAS
CSCD
北大核心
2000年第3期330-338,共9页
Acta Pedologica Sinica
基金
国家自然科学基金!(编号:39830220)
