水溶性有机物对水田土壤中水溶性氮磷含量及其利用率的影响

Effects of water-soluble organic materials on nitrogen and phosphorus content and use efficiency in a paddy soil.

采用田间微区试验,研究了施用有机物料对土壤氮磷的变化动态及活性的影响。结果表明,水稻生长过程中土壤溶液中水溶性氮(铵态氮、硝态氮)及磷的含量都随着时间的延长而下降,且氮、磷含量的变化与施入的化学肥料量以及溶液中DOC含量有关;有机物料施用增加了水稻的生物量和对氮、磷的吸收利用;15N示踪显示,与对照的化肥处理相比,施用有机物料处理的微区氮肥利用率及土壤残留率明显增加,同时减少了土壤氮磷的损失。

With micro-plot experiment, this paper studied the effects of applying organic materials on the dynamics of nitrogen and phosphorus, and their availability in paddy soil. The results showed that during rice growth period, the nitrogen （ammonia-N and nitrate-N） and phosphorus contents in soil solution were decreased with time, and significantly correlated with the dosage of chemical fertilizers and the DOC content in soil solution. Organic materials application could not only increase rice biomass, but also increase the use efficiency of nitrogen and phosphorus fertilizers. ^15N tracer indicated that compared with applying chemical fertilizers, organic materials application could significantly increase the availability and maintenance of soil nitrogen, which in turn decreased soil nitrogen loss.