黄土高原草地植被土壤团聚体特征与可蚀性分析  

Study on Soil Aggregate Stability and Soil Erodibility in the Grassland Vegetation of the Loess Plateau Region

作　　者：曾全超 李娅芸 刘雷[3] 安韶山[1,3] 

机构地区：[1]中国科学院教育部水土保持与生态环境研究中心黄土高原土壤侵蚀与旱地农业国家重点实验室,陕西杨陵712100 [2]中国科学院大学,北京100049 [3]西北农林科技大学资源环境学院,陕西杨陵712100

出　　处：《草地学报》2014年第4期743-749,共7页Acta Agrestia Sinica

基　　金：国家自然科学基金(41030532)(41171226);新世纪优秀人才支持计划(NCET-12-0473);西北农林科技大学"优秀人才科研专项"(QN2011049)资助

摘　　要：通过对黄土高原典型草地不同植被类型的土壤团聚体分布特征以及土壤可蚀性的分析,探讨了不同立地条件下土壤团聚体特征与土壤可蚀性之间的关系,以期为防止土壤侵蚀提供理论依据.结果表明：Le Bissonais法的3种处理,慢速湿润处理（SW）后土壤团聚体粒径主要为＞2 mm的大团聚体颗粒,预湿后扰动处理（WS）和快速湿润处理（FW）后团聚体粒径分布较均匀,＜0.2 mm粒径的团聚体颗粒占主要优势.土壤团聚体平均质量直径表现为SW＞WS＞FW,土壤可蚀性值K表现为WS＞ FW＞ SW,表明黄土丘陵区草地植被土壤团聚体破碎的机制主要是消散和机械破坏.不同立地条件下,对于慢速湿润处理,0～10 cm土层阴梁峁坡、阴沟坡、阳沟坡的土壤团聚体平均质量直径显著高于梁峁顶和阳梁峁坡,阳梁峁坡和梁峁顶的土壤可蚀性值K显著低于阴梁峁坡、阴沟坡和阳沟坡,10～20 cm也表现出相似的变化规律.阳梁峁坡和梁峁顶的土壤团聚体稳定性较低,土壤抗蚀性差,阴梁峁坡、阴沟坡和阳沟坡土壤的团聚体稳定性较好,土壤抗侵蚀能力较好.Soil aggregate stability is a key indicator of soil quality evaluation.Soil samples under different plant communities and site conditions were collected in Gaojiagou watersheds located on the hilly gullied Loess Plateau of northern Shaanxi.Soil water stable aggregate were measured by using Le Bissonnais （LB） method.The mean weight diameter （MWD） and soil erodibility （K value） of soil aggregates were calculated.The results show that the MWDs of three treatments （fast wetting-FW,slow wetting SW,and wet stirring-WS） are ordered as SW 〉 WS〉 FW,and the K values of treatments were ordered as FW〉 WS〉 SW.The MWDs are also ordered as shady ridge slope〉 shady gully slope〉 sunny gully slope〉 ridge top〉 sunny ridge slope,the K values are ordered as sunny ridge slope〉 ridge top〉 sunny gully slope〉 ridge slope〉 shady gully slope.The MWDs of shady ridge slope,shady gully slope and sunny gully slope are significantly higher than that of ridge top and sunny ridge slope.Soil erosion has easily taken place in the ridge top and sunny ridge slope.

关 键 词：草地植被 Le Bissonais法 土壤团聚体 土壤可蚀性 黄土高原区 

分 类 号：S152.4[农业科学—土壤学] S157[农业科学—农业基础科学]