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为了确定南四湖区农田合理的氮磷肥投入量,减轻氮磷流失风险,对不同氮磷水平下稻田的稻谷产量及肥料吸收利用情况进行研究。结果表明,不施氮磷肥使耕层土壤氮磷含量明显下降,稻谷产量显著降低;减施30%氮磷肥显著提高了氮磷肥利用率,降低了稻谷产量。过量施用氮磷肥处理对稻谷产量无显著效果,且显著提高了耕层土壤硝态氮含量,明显降低了氮磷肥利用率,促进了水稻对氮素的积累,对水稻磷素积累无显著效果。稻谷氮磷累积量明显高于稻草,稻谷和稻草含氮量均随氮磷肥施用量的增加而增大。氮磷肥利用率随氮磷肥施用量的增加而降低。减施15%氮磷肥对土壤氮磷含量和稻谷产量均影响不大,显著提高了氮磷肥利用效率,降低了经济成本,减轻了氮磷素流失风险,是南四湖区稻田较好的氮磷肥施用模式。
In order to determine the reasonable inputs of N and P in farmland in Nansi Lake and reduce the risk of N and P losses, the yield and fertilizer use efficiency of paddy fields under different levels of N and P were studied. The results showed that N and P fertilizers significantly decreased soil nitrogen and phosphorus contents, and significantly reduced the grain yield of paddy soils. The application of 30% N and P fertilizers significantly increased the N and P fertilizer use rates and reduced the grain yield. Over-application of N and P fertilizer had no significant effect on paddy grain yield, and significantly increased the nitrate nitrogen content of topsoil, significantly reduced the utilization of N and P, promoted the accumulation of nitrogen in rice and had no significant effect on phosphorus accumulation in rice. The accumulation of nitrogen and phosphorus in rice was significantly higher than that in straw, and the nitrogen content in rice and straw increased with the increase of nitrogen and phosphorus fertilizer application. Nitrogen and phosphorus use efficiency decreased with the application of nitrogen and phosphorus fertilizer. Nitrogen and phosphorus fertilizers reduced 15% of the soil N and P content and rice yield have little effect, significantly improve the N and P use efficiency, reduce economic costs and reduce the risk of nitrogen and phosphorus loss, rice fields in Nansi Lake better nitrogen and phosphorus fertilizer Application mode.