【摘要】 通过8年定位试验,研究了秸秆还田对潮褐土及其微团聚体磷素吸附与解吸特性的影响,从各级微团聚体磷素吸附与解吸储量角度探讨了不同施肥制度下土壤磷素吸附与解吸性能的变化实质。结果表明:麦秸和玉米秸直接还田配施常量NPK化肥主要是通过降低<10μm粒级微团聚体的吸附储量(减少13.7～14.8 g·kg-1)和提高大粒级,特别是10～50μm粒级微团聚体磷的解吸储量(增加2.1～2.8 g·kg-1),使土壤的供磷能力得到改善;不施肥和单施常量NPK化肥则主要是由于<10μm粒级对磷的吸附储量增加(分别上升47.7 g.kg-1和12.3 g·kg-1)和大粒级的解吸储量降低(10～50μm粒级分别减少2.1g·kg-1和0.9g·kg-1),造成全土的吸附性能下降。土壤磷吸附性能与有机碳含量和微团聚体组成关系密切。更多还原

【Abstract】 Eight years’ location experiment was conducted in meadow cinnamon soil in Hebei Province to study the effect of returning straw into field on characteristics of absorbed and desorbed P in soil and micro-aggregates,the changes of P absorption and desorption capacity under different fertilizer regimes from the view points of the storage of P in various micro-aggregates.The results showed that application of wheat straw and maize straw combined with constant NPK fertilizer mainly decreased P absorption capacity in <10μm micro-aggregates(a decrease of 13.7～14.8 g·kg-1) and increased the storage of desorbed P in bigger,especially in 10～50μm micro-aggregates(an increase of 2.1～2.8 g·kg-1),and improved soil P supplying capacity.While no fertilization and application of constant NPK fertilizer mainly increased the storage of absorbed P in <10μm micro-aggregates(an increase of 47.7g·kg-1and 12.3g·kg-1,respectively),and decreased P desorption capacity in bigger micro-aggregates(a decrease of 2.1g·kg-1and 0.9g·kg-1 in 10～50μm micro-aggregates,respectively),and resulted in the decrease of soil P absorption.Soil P absorption capacity was in close relation with the content of organic C and the composition of micro-aggregates.更多还原