典型喀斯特地区土壤退化机理探讨：不同土地利用类型土壤水分性能比较  

Mechanisms of soil degradation in southwest karst area of China: Characteris- tics of soil water properties of different land use types

作　　者：赵中秋[1] 蔡运龙[2] 付梅臣[1] 白中科[1] 

机构地区：[1]中国地质大学(北京)土地科学技术学院,北京100083 [2]北京大学环境学院资源环境与地理学系,北京100871

出　　处：《生态环境》2008年第1期393-396,共4页Ecology and Environmnet

基　　金：国家自然科学基金重点项目(40335046);中国地质大学(北京)“土地利用创新团队”项目;中国地质大学(北京)科学技术基金(200702)

摘　　要：我国西南喀斯特生态脆弱区以土壤退化为核心的环境退化形势严峻。揭示土壤退化过程和退化机理,是认识喀斯特这个特殊环境的土地生态系统诸多环境退化问题的一个重要途径。本文选择黔中猫跳河流域上游长顺县广顺乡典型喀斯特景观为研究区,通过野外采样和实验室分析,对不同土地利用类型的土壤水分性能进行了比较研究,以探讨喀斯特地区土壤退化的过程与机理。结果表明,与基本无退化的本底林地相比较,草地土壤的水分性能明显变劣,表现为:土壤的持水能力下降,田间持水量和毛管持水量分别下降49.5%和56.2%;土壤供水能力降低,总有效含水量下降56.4%;土壤渗透性能减弱,150min饱和渗水量减少70.1%。土壤的这些水分特征与土壤发生的强度和速度都有着非常密切的关系,草地土壤水分性能的这种退化将加剧土壤的侵蚀。可以认为,在西南典型喀斯特地区,土壤的水分退化是土壤退化的一个关键过程和因素。The eco-environmental problems characterized with soil degradation in the southwest karst area of China are severe due to the increasing conflict between land and population. It＇s considered that research on the machanisms of soil degradation may be an important way to understand many of the problems about the degradation of this special ecosystem. The characteristics of soil water properties of two different land use types, forest land and grass land, in typical karst area in middle-Guizhou, southwest of China, were investigated. The results showed that, compared to the forest land, the soil water properties of grass land were in degradation： the natural water content was low comparatively; the soil water holding capacity were reduced significantly （field capacity reduced by 49.5% and capillary capacity reduced by 56.2%, respectively）, and the total available water capacity were reduced by 56.4%; the soil water permeabifity also declined significantly, with 150 min＇s filtrated water content decreased by 70.1%. All of the soil water properties analyzed above are closely related to the intensity and rate of soil erosion. Accordingly, the degradation of soil water properties of grass land as showed in the above results necessarily accelerates soil erosion. And it can be considered that, for the special eco-environment in southwest karst area of China, the degradation of soil water properties may be one of the key processes or factors of soil degradation.

关 键 词：喀斯特地区 土壤退化 土壤水分性能 

分 类 号：X144[环境科学与工程—环境科学]