【摘要】 【目的】评估秸秆还田过程中不同因素对农田土壤氮素水平的影响。【方法】基于Meta分析，在中国知网、Web of Science及Science of Direct搜集秸秆还田文献42篇，共得到314对数据，量化秸秆种类、土壤初始条件、秸秆还田方式、秸秆还田量、氮肥配施量以及秸秆还田年限对土壤氮素水平的影响。【结果】不同种类秸秆还田均能够提高土壤总氮量；相比黏土，秸秆还田更有利于促进砂土和壤土的氮素积累；在碱性土壤条件下进行秸秆还田，土壤固氮效果较好；秸秆还田后土壤氮素提升率随土壤碳氮比的增加而下降；采用翻耕、旋耕和免耕进行秸秆还田分别提升了9.11%、7.84%、5.34%的土壤总氮量；秸秆还田过程中少量（≤150 kg/hm~2）和中量（150～250 kg/hm~2）配施氮肥条件下的土壤固氮效果较为接近，氮肥施用量?250 kg/hm~2时，土壤氮素积累效果显著提升；长期秸秆还田（?10 a）与短期秸秆还田（1～4 a）取得的土壤增氮效果接近。【结论】碱性、低碳氮比的非黏性土壤更有利于秸秆腐解及氮素释放，为促进土壤氮素积累，建议在合理配施氮肥条件下将秸秆以翻耕的方式进行中短期（≤10 a）还田。更多还原

【Abstract】 【Objective】Straw return not only improves soil fertility but also soil structure and soil health. In this paper we systematically analyze the effects of different biotic and abiotic factors on effect of straw return on soil nitrogen.【Method】The meta-analysis was based on 42 papers indexed by CNKI, Web of Science and Science of Direct, in where there were 314 pairs of data that compared nitrogen change in soils with and without straw return.Other factors considered include straw types, soil conditions prior to straw return, straw return methods, straw return amount, nitrogen fertilization, years after inception of straw return.【Result】Regardless of straw types, straw return increased total soil nitrogen content. Straw return promoted nitrogen accumulation in sandy and loam soil more than in clay soils. In alkaline soils, straw return improved nitrogen fixation. The efficacy of straw return in increasing soil nitrogen decreased with the increase in carbon-nitrogen ratio of organic matter in soil. Compared to soil without straw return, straw return combined with plowing, rotary tillage, and no-tillage increased soil total nitrogen content by 9.11%, 7.84% and 5.34%, respectively. Straw return also increased soil nitrogen accumulation, but the increase was not significantly dependent on straw amount. Applying less than 150 kg/hm~2 of straw improved soil nitrogen fixation at the same level as applying 150-250 kg/hm~2 of straw. When nitrogen fertilization exceeded 250 kg/hm~2,straw return significantly increased soil nitrogen accumulation. The length of period over which straw return was implemented did not affect soil nitrogen significantly, and the effect of long-term straw return application(>10 a)and short-term straw return application(1-4 a) on soil nitrogen change was approximately the same.【Conclusion】Coarse alkaline soils with low C/N ratio facilitate straw decomposition and nitrogen mineralization. Our results show that combining straw return with tillage and rational nitrogen fertilization was effective in improving soil nitrogen accumulation in soils where straw return application had been implemented for less than 10 years.更多还原