为探讨贵州威宁草海在不同土地资源利用方式下土壤理化性质的差异,选择草海流域6种不同土地利用类型(草地、耕地、茶叶林、杉木林、滇杨林、针阔混交林)的不同土层(0~20 cm,20~40 cm,40~60 cm)土壤为研究对象,分别对土壤物理性质及养分含量进行测定与分析,探究土地资源利用方式差异对土壤理化性质的影响。结果表明:1)草海流域土壤全量养分及有机碳含量处于全国的中低水平,速效养分含量表现为N低P高K中等,土壤养分含量不均衡,且主要受限于N元素。2)土地利用方式的不同导致土壤结构及养分含量具有一定差异,草地的土壤容重均值最大,针阔混交林最小;滇杨林的土壤孔性最好,草地和耕地最差;茶叶林的全量养分含量均高于其他立地土壤,针阔混交林的有机碳、有效磷及速效钾的平均含量最高,草地的碱解氮含量最高。3)Pearson相关性分析表明,土壤有机碳含量与土壤物理结构及N,P,K元素含量均具有不同程度的相关性,表明有机质的添加有利于改良土壤理化性质。4)从土壤质量恢复的角度看,乔、灌木林分有利于提高土壤质量。

In order to explore the differences in physiochemical properties of soil of different land resource utilization modes in Chaohai,Weining in Guizhou Province,the soils in different soil layers(0-20 cm,20-40 cm,40-60 cm) under six different land use types(grassland,farmland,Camellia sinensis shrub,Cunninghamia lanceolata forest,Populus yunnanensis forest and conifer-broadleaf forest) were chosen as the research objects.The effects of different land use types on soil quality were studied by measuring and analyzing physical structure and nutrient content of soil.The results showed that:1) The total nutrient and organic carbon contents of soil in Caohai watershed were at a medium-low level in China,the available nutrient contents were low in nitrogen,high in phosphorus,and medium in potassium,the soil nutrient contents were unbalanced and mainly limited by nitrogen.2) The structure and nutrient content of soil were different due to different land use patterns.The average soil bulk density of the grassland was the largest and the conifer-broadleaf forest was the smallest.The porosity of Populus yunnanensis forest was the largest and that of grassland and farmland was the smallest.The total nutrient content of Camellia sinensis shrub was higher than that of other sites soil,the soil organic carbon,available phosphorus and available potassium content of conifer and broadleaf mixed forest was the highest,the content of alkali-hydrolysable nitrogen in grassland was the highest.3) The organic carbon content of soil was related to the physical structure and the content of nitrogen,phosphorus and potassium soil on the basis of Pearson coefficients analysis,indicating that the addition of organic matter is conducive to improving soil physical and chemical properties.4) From the perspective of soil quality recovery,the arbor and shrub stands are beneficial to improve soil quality.