紫色土无机—有机肥配施下作物生物效应及土体NO_3^-N运移特点

Movement of nitrate under mixed application of inorganic and organic fertilizers in purple soil

本文研究了无机—有机肥配施下紫色土土壤NO-3 N在剖面的运移特征,同时对作物N吸收、N肥利用率及各施肥处理的产量效应进行了分析。结果表明,分蘖期和成熟期土壤剖面NO-3 N含量分布差异显著,各处理NO-3 N向下移动量顺序为:纯化肥>鸡粪+化肥>猪粪+化肥>秸秆+化肥处理;各施肥处理对土壤NO-3 N累积的影响则明显的反映了纯化肥处理土壤NO-3 N移动较快,鸡粪矿化强烈、释放快,猪粪释放缓慢特点,秸秆与化肥配施处理对NO-3 N的滞留作用较为显著,证实了某些有机肥的施用对NO-3 N的淋失有一定的固持作用,阻碍了NO-3 N向下迁移;结合N肥的利用率、产量和农艺性状等特点分析,建议当地采用秸秆或猪粪的有机+无机施肥制度。

Nitrate movement and accumulation in the profile of purple soil under mixed application of several inorganic-organic fertilizers were studied in this paper. Meanwhile,nitrogen absorbed by plant,nitrogen recovery,yield and biological effects were analyzed. The results showed that the distribution of soil nitrate in the profile behaved as quite different during tillering stage and mature period. The quantity of nitrate moved downward in the profile as follow: chemical fertilizer >chicken manure +chemical fertilizer >pig manure +chemical fertilizer > straw +chemical fertilizer. Under the pure chemical fertilizer treatment,soil nitrate moved quickly. The mineralization of chicken manure was strong, however,mineral N release from pig manure treatment was slow.The retaining effect under mixed application of straw and chemical fertilizer was obvious. The results showed that soil nitrate leaching was kept by some manure to some degree. With comprehensive comparison of nitrogen recovery, production and agronomy properties,fertilizer management techniques with mixed application of pig manure or straw and chemical fertilizer was proposed in this paper.