片麻岩山地土壤团聚体分布及养分特征

Distribution and Nutrient Charicteristics of Soil Aggregates in Gneiss Mountainous Region

为了探明太行山片麻岩山地土壤团聚体的分布及养分特征,以河北省平山县为试验地,研究了土壤团聚体分布、土壤养分特征以及各粒级土壤团聚体的养分贡献率。结果表明,风化层、半风化层土壤团聚体均以0.5~1mm粒级为主,2~5mm粒级次之,1~2mm粒级团聚体含量最少。有机质、全氮、碱解氮、全磷、有效磷、全钾、速效钾含量在团聚体中的分布存在一定差异。其中有机质、碱解氮含量均随着团聚体粒径的增大而升高;有效磷含量随团聚体粒径的增大呈现先增大后减小的趋势;全氮、全钾、速效钾含量在团聚体中的分布相对较均匀;而全磷含量在〉5 mm粒级团聚体中最高,在其他粒径团聚体中分布均匀。不同粒级团聚体对土壤主要养分的贡献率有所不同,其变化趋势与土壤团聚体含量分布一致。总体来看,土壤团聚体中的养分约90%来自〉0.25mm粒级的团聚体。

In order to explore the distribution and nutrient characteristics of soil aggregates in gneiss mountainous area of Taihang Mountains,we established sample plots in Pingshan county,Hebei province,to study the distribution of soil aggregates,soil nutrient characteristics and nutrient contribution rates of soil aggregates of different particle sizes.The results showed that in half-weathering and weathering layer,the particle sizes of soil aggregates were mainly within 0.5~1mm,and then in 2~5mm,while the proportion of 1~2mm soil aggregates was the lowest.The distribution patterns of soil organic matter,total nitrogen,available nitrogen,total phosphorus,available phosphorus,total potassium,and available potassium in different sizes of soil aggregates were different.The contents of soil organic matter and available nitrogen increased with the increasing particle size of soil aggregates,while the content of available phosphorus increased at first and then decreased with the increasing particle size.Total nitrogen,total potassium,and available potassium uniformly distributed in different particle sizes of soil aggregates.The content of total phosphorus was the highest in 〉5mm aggregates,while uniformly distributed in aggregates of other particle sizes.The nutrient contribution rate changed a lot among different particle sizes of soil aggregates,showing a similar variation trend with soil aggregate content.Overall,about 90% of nutrient content in soil aggregates came from 〉0.25 mm aggregates.