作物秸杆还田对土壤养分含量的影响

农业生产中大量使用化肥等造成利用率降低、环境污染严重。农作物秸秆中含有大量氮、磷、钾及其他微量元素。秸秆还田可以提高土壤有机质、改善土壤结构、增加土壤肥力，但不同作物品种不同产量水平条件下秸秆还田对土壤肥力产生的作用有所不同。通过两年试验得出棉花、小麦、玉米不同产量水平条件下的经济系数、秸杆还田量、秸杆养分还田量及秸杆还田后土壤养分含量的变化情况，为精准施肥、培肥地力提供理论依据。

The Effect on Soil Fertilization of Crop Stalk Returning to Fields

The massive use of chemical fertilizer in agriculture cuts down the usage percentage of barnyard fertilizer and makes the environmental pollution more serious. The crops straw stalks contain lots of nitrogen, phosphorus, potassium and other trace elements. Reuse of the straw stalk can enhance the ulmin in soil, improve soil structure and increase soil fertility. But under the different crop assortment and different production level condition, the functions of the straw stalk give the soil fertility different interferences. After two years experiment, including cotton, wheat and corn, we have got the economical coefficient, the reuse rate of the straw stalk, the reuse rate of straw nutrient and the situation of the soil nutrient in different output condition. All the results provide the theoretical basis for well fertilization of the soil.