不同氮肥运筹下水稻秸秆腐解特征及对稻茬小麦产量和土壤养分的影响

Effects of Different Nitrogen Application Rates on Rice Straw Decomposition,Rice-after Wheat Yield and Soil Nutrient

于2014~2015年在稻茬小麦栽培条件下,研究了不同氮肥运筹对水稻秸秆腐解特征、小麦产量、氮肥利用率及土壤养分含量的影响。结果表明:高氮(375 kg/hm2)投入能加速水稻秸秆的腐解速度;中氮(300 kg/hm2)施用有利于小麦形成协调的产量结构和较高的经济产量;水稻秸秆还田能够增加麦田土壤钾素及有机质含量。结论:在水稻秸秆全量还田条件下,在中氮水平的基础上适当增加氮素的投入,更有利于水稻秸秆的腐解、小麦氮素利用率和产量的提高。

Under the condition of wheat cultivation after rice harvest during 2014 - 2015, the effects of different nitrogen fer- tilizer application rates on the decomposition characteristics of rice straw, the grain yield and nitrogen use efficiency of wheat, and the soil nutrient content in wheat field were studied. The results indicated that： the application of high nitrogen （375 kg/hm2） could accelerate the decomposition of rice straw; the application of moderate nitrogen （ 300 kg/hm2） could harmonize the yield structure of wheat and obtain higher economic yield; returning rice straw to the field could increase the contents of potassium and organic matter in wheat field soil. The following conclusion is obtained： under the condition of returning whole rice straw to the field, the application rate of nitrogen should be properly increased on the basis of moderate nitrogen （ 300 kg/hm2 ） , which is more advantageous to the decomposition of rice straw, and the improvement of wheat yield and nitrogen use efficiency.