摘要： 经8年田间定位试验,研究了不同施肥制度下褐土及其微团聚体碳、氮分布规律,从各级微团聚体组成变化及碳、氮储量角度探讨了不同施肥制度下土壤肥力的变化实质。结果表明,不同施肥制度下土壤微团聚体组成变化各异,不施肥和单施常量NPK化肥主要是由于10~50μm粒级碳、氮储量降低而造成土壤肥力下降;增量NPK化肥可保持肥力不降低,但投入较高;有机肥(物)料配施常量NPK化肥则主要通过增加大粒级特别是10~50μm粒级碳、氮储量而使土壤肥力水平得到提高。采用有机肥(物)料配施常量NPK化肥是改善褐土肥力的有效措施。

关键词: 施肥制度, 褐土, 微团聚体, 碳、氮分布, 储量变化

Abstract: Eight years 'location experiment was conducted in cinnamon soil in Hebei province to study the distribu- tions of organic carbon and nitrogen in soil and its micro-aggregates,and to study the changes of the soil organic carbon and nitrogen fertility under different fertilization regimes from the view points of the storage of organic carbon and total N in various micro-aggregates. The results showed that the composition of soil micro-aggregates is different under different fertilization regimes. No fertilization and application the constant NPK fertilizers mainly decrease the storage of organic carbon and nitrogen in 10- 50 μ m, and resulted in soil fertility decrease. Application the increment NPK fertilizers can maintain the soil fertility,but the input ishigh. Application organic manure combined with constant NPK fertilizers mainly decreases the storage of organic carbon and nitrogen in bigger sizes,especially in 10-50 μ m micro-aggregates,and im- proves soil fertility. And it is the most effective way to improve soil fertility.

Key words: Fertilization regimes, Cinnamon soil, Micro-aggregates, Distribution of organic carbon and nitrogen, Stor-age change

中图分类号: 

• S158.5