岩溶山区不同土地利用方式下土壤质量指标响应

探讨了岩溶山区不同土地利用方式与土壤质量指标之间的响应关系.对重庆市北碚岩溶山区土壤肥力指标进行主因子分析的结果表明,原有22个土壤质量指标可归为4 类,分别以有机质,有效含水量,通气孔隙度,细菌、真菌数量百分比为代表,这4类因子基本反映了土壤质量随土地利用变化的综合变化状况.通径分析表明,不同土地利用方式下土壤持水性能主要与有机质、＞0.25 mm水稳性团聚体有关,二者的效应均大于黏粒.在土地利用方式变化过程中,土壤质量变化体现在有机质含量、土壤供持水能力、土壤结构状况和土壤微生物特性的变化上.

Response of Soil Quality Indexes to Land Use of Different Patterns in Karst Mountains

Responses of soil quality indexes to land use of different patterns were explored.Results show that by using the Main Factor Analysis Method the 22 soil quality indexes in the Beibei karst mountain region of Chongqing could be sorted into 4 categories represented,respectively,by organic matter,available soil water,aeration porosity,and percentage of bacteria. The 4 categories reflect basically comprehensive conditions of soil quality.Path analysis shows that soil water holding(capacity) under different patterns of land use is mainly correlated with organic matter,and >0.25 mm water stable aggregates,and their effects are higher than that of clay.When land use patterns changed,changes in soil quality were embodied in content of organic matter,soil water holding and supplying capacity,soil structure and soil microbial characteristics.