不同土地利用方式对高原喀斯特洼地土壤主要特性的影响

目的]研究不同土地利用方式对高原喀斯特洼地土壤主要特性的影响。方法]通过1∶10000地形图对特定高原喀斯特洼地不同土地利用方式进行划分与归类,分层取样分析土壤剖面特性、理化性质变化。结果]土层（A＋B层）厚度的变化趋势为坡耕（退耕林）地〉天然林地〉人工林地〉灌木林地,土壤剖面特征、水源涵养、颗粒组成、土壤肥力与肥力有效性的相关指标在不同利用方式间发生了相似或相异的规律性变化。土壤综合质量指数的变化趋势为耕地〉退耕林地〉坡耕地、天然林地〉人工林地。耕地土壤综合质量最高,是自然成土和人为经营的结果。3～5年的退耕林地土壤综合质量高于坡耕地,表明造林措施是改善喀斯特洼地坡耕地土壤质量的有效手段。天然林土壤综合质量高于人工林地,这为利用＂近自然经营＂技术改善喀斯特洼地土壤质量提供了依据。结论]该研究可为喀斯特地区石漠化的生物治理、土壤质量演化的生物学控制技术提供理论依据。

Study on Influences of Different Land Use Types on Soil Qualities in Plateau Karst Depression

Objective] The aim was to study influences of different land use ways on soil qualities in plateau karst depression.Method]Different land use types were divided by topographic map of 1∶10 000 scales and soil properties of physics and chemistry were analyzed.Result]The results showed that the variation trend of soil depth (A+B stratum) was slope plough (include returning farm to forest) land >natural forest land>planted forest land>shrub forest land,and relative indexes changing regularities of soil sections,soil water conservation,soil particle composition,soil fertility and soil fertility effectives in different land use types were studied.Change trend of soil synthetic quality was cultivated land>returning farm to forest land>slope plough land,natural forest land>planted forest land.High soil synthetic quality of cultivated land was result of natural soil-forming and human managing processes,soil synthetic quality of returning farm to forest land in 3-5 year was higher than that of slope plough land indicated a effective method to improve slope plough soil quality in karst depression,and soil synthetic quality of natural forest land was higher than that of planted forest land provided an evidence to use near-nature manage technology to improve soil quality in karst depression.Conclusion]The study will provide theoretical basis for bioremediation of rocky desertification and biological control technology of soil quality evolution.