山地森林/干旱河谷交错带不同植被条件下土壤团聚体及其腐殖质分布特征

Distribution of Soil Aggregates and Its Humus Under Different Vegetation Types in Mountain Forests-Arid Valley Ecotone

采用野外调查和室内分析相结合的方法,立足于山地森林/干旱河谷交错带,对不同植被条件下土壤团聚体及其腐殖质分布特征进行研究。结果表明：不同植被条件下土壤团聚体的组成均以〉2mm粒径团聚体为主,占团聚体组成的60%左右。土壤团聚体中腐殖质及其组分分布存在一定差异,随团聚体粒径的减小无明显规律,整体表现为〈1mm粒径团聚体中腐殖质及其组分的含量高于〉1mm粒径团聚体。各粒径团聚体对腐殖质及其组分的贡献率约46%～60%来自〉2mm粒径团聚体,这与〉2mm粒径团聚体的含量较大有关。

By used field investigation and laboratory analysis methods,based on the mountain forests-arid valley ecotone,distribution characteristics of soil aggregates and its humus under different vegetation types were studied.The results showed that：The contents of soil aggregates were dominated by 〉2mm（nearly60%）.The distribution characteristics of humus and it＇s components in soil aggregates had the discrepancy under different vegetation types,with the reducing of aggregate size it does not show obvious regularity,the contents of humus and its components in 〈1mm aggregates were higher than that in〉1mm aggregates.Each particle size aggregates on soil humus and it＇s component contribution rate about 46%～60%come from〉2mm aggregates,this mainly due to the contents of〉2mm aggregates were the largest.