在陇东黄土高原较为贫瘠的土壤依托定位试验，研究不同秸秆还田年限对土壤理化特性及微生物的影响。结果表明，秸秆还田能够显著提升土壤的贮水能力，降低土壤容重及增加土壤孔隙度，改善土壤的结构，同时还能增加土壤有机碳的含量，对较深耕层土壤有良好的改良效果。秸秆还田能增加0～30 cm耕层土壤的微生物数量，且随着还田年限的增加，显著改善土壤微生物群落结构。

The effects of different straw returning years on soil physical and chemical properties and microorganism were studied in the lean soil of the loess plateau in East Gansu. The results showed that straw returning can significantly improve soil water storage capacity， decrease soil bulk density， increase soil porosity， improve soil structure， and increase soil organic carbon content， which has a good effect on deep surface soil. Straw returning can increase the microbial population of surface soil by 0~30 cm， and significantly improve the microbial community structure in soil with the increase of the years of returning.

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