有机肥替代对土壤养分的影响

为探寻肥料的合理施用方法,并对有机替代的可行性提供佐证,运用大田定位试验方法,研究连续3季有机肥部分替代无机肥料对土壤养分全氮、全磷、速效钾、有效磷、有机质含量的影响,及在各养分土壤剖面中的分布和迁移特征。结果表明,连续3季施用不同类型肥料后,各处理土壤全氮、全磷、有机质、有效磷主要积累在0~20 cm土层,随着土层深度的增加而降低。添加20%干猪粪的处理前期效果不显著,后期养分含量显著增加。20%M处理（20%减量施肥+商品有机肥）在0~20、20~40 cm土层各养分含量都高于NPK处理（农民习惯）,全氮、全磷、有效磷、有机质能发生明显迁移,在20~40 cm土层固定累积向下淋溶损失小。结果表明,化肥减量添加商品有机肥能平衡养分分布,提升土壤综合肥力,具有培肥地力的作用。

Organic Fertilizer Substitution: Effects on Soil Nutrients

To explore the reasonable fertilization way and provide evidence for the feasibility of organic fertilizer substitution, the authors conducted the partially substitution of inorganic fertilizer by organic fertilizer in three consecutive seasons and studied the effects on the content of total nitrogen, total phosphorus, available potassium, available phosphorus and organic matter in soil, as well as the distribution and migration characteristics of nutrients in each soil profile. The results showed that the total nitrogen, total phosphorus, organic matter and available phosphorus in soil were mainly accumulated in the 0-20 cm soil layer and decreased with the soil depth after the treatment of different types of fertilizers for three consecutive cropping seasons. The effect of 20% dried pig manure substitution was not significant in the early stage, but the nutrients’ content increased significantly in the later stage. The nutrient contents of 20% treatment (20% reduced fertilization + commercial organic fertilizer) in 0-20 and 20-40 cm soil layers were higher than those of NPK treatment (farmer conventional). The total nitrogen, total phosphorus, available phosphorus and organic matter obviously migrated, and the accumulated leaching loss in 20-40 cm soil layer was slight. In conclusion, the substitution of inorganic fertilizer by commercial organic fertilizer could balance the nutrients’ distribution, improve the comprehensive fertility of soil and play a role in soil fertility cultivation.