旱地玉米秸秆还田对土壤肥力的影响

 研究探讨了玉米秸秆还田方式 (直接或过腹还田 )与化肥配施对土壤养分变化的影响。研究表明 ,秸秆过腹还田对提高耕层土壤速效 N贡献较大 ;耕层土壤速效 P含量主要与化肥施用量有关 ;耕层土壤速效 K含量与秸秆直接还田有关。该试验条件下 ,秸秆直接还田和秸秆过腹还田的土壤有机质含量基本保持平衡。产量统计分析表明 ,化肥对提高玉米产量及水分利用效率有明显影响 ,其次为秸秆直接翻压还田。适宜的秸秆直接还田量、秸秆过腹还田量与化肥 N配比 (试验中每公顷用量分别为 60 0 0、1 50 0和 1 0 5kg) ,其产量、水分利用效率和肥料 N的利用效率较高。研究为该区玉米秸秆作为饲源和有机肥源的合理再分配利用 ,秸秆、牛粪与化肥平衡配施 ,以及秸秆还田对土壤肥力的贡献和对作物产量的影响提供了依据。

Effects of Corn Stover Incorporated in Dry Farmland on Soil Fertility

Seven years field experiments on application of corn stover and/or cattle manure combined with chemical fertilizers were carried out in Shouyang Dryland Farming Experimental Station. Results showed that the increased available N in tilth layer was mainly influenced by the application of cattle manure; available P content in tilth layer was mainly influenced by chemical fertilizer; available K in tilth layer was mainly influenced by the incorporation of corn stover. The organic matter content in the soils treated with corn stover or cattle manure were kept in balance under the experimental conditions. Corn yield and water use efficiency were influenced significantly not only by fertilizer N but also by incorporated corn stover. The results suggested that the highest N uptake, yield and water use efficiency could be obtained at rates of 105 kg fertilizer N, 6000 kg corn stover, and 1500 kg cattle manure per hectare. The experiments supply information on nutrient recycling and use of corn stover as sources of fodder and organic fertilizer. This information is also useful for balancing application of organic and inorganic fertilizer, improving soil fertility and increasing crop yield with application of corn stover.