论文部分内容阅读
坝系土壤粒径均以粉粒为主，含量占土壤的６６％～７０％。各土壤间粉粒含量差异很小，所不同的是，坝地富粘层粗粉粒少细粉粒多，砂粒少粘粒多，坝、坡轻壤层反之。土壤ＯＭ、ＴＮ主要集中在粘粒中，其浓度在粗细颗粒中差别悬殊。ＴＰ及ＴＫ在粗细颗粒中这种差别就较小。土壤中各形态锌均随着土壤颗粒变细而浓度增加，在＜０．００５ｍｍ粒径中浓度陡然提高。故坝地富粘层中ＯＭ、ＴＮ、ＡＺｎ的含量最丰。上述粒径及养分分布特点，揭示了在泥沙迁移淤积过程中，坝地不同部位土壤养分差异的内在原因。
The grain size of the dam system is dominated by silt, accounting for 66% ~ 70% of the soil. Differences in the content of powder between the soil is very small, the difference is that the thick clay-rich coarse grain less fine sand and more sand and less clay, dam, slope light soil layer on the contrary. Soil OM, TN mainly concentrated in the clay, the concentration of the difference in the thickness of the particles. TP and TK in the thickness of the particles in this difference is smaller. All forms of zinc in the soil with the soil particles become thinner and the concentration increased in the <0.005mm particle size increased sharply. Therefore, the rich clay in the dam OM, TN, AZn content of the most abundant. The above characteristics of particle size and nutrient distribution reveal the inherent causes of soil nutrient differences in different parts of the dam during the process of sediment migration and sedimentation.