喀斯特石漠化的研究现状与存在的问题

喀斯特石漠化是土地荒漠化的主要类型之一。喀斯特生态系统的脆弱性决定了喀斯特生态系统的易损性和退化喀斯特生态系统的难恢复性,但它与发生石漠化并没必然的联系,喀斯特石漠化是岩溶生态系统退化的结果,而不是喀斯特生态系统脆弱性的必然表现。故所指的喀斯特石漠化,特指人为加速的石漠化,属于人为荒漠化的一种类型,但强调喀斯特石漠化的人为成因性,并不是否定自然背景对喀斯特生态系统的制约作用。石漠化土地的分类既要能反映出石漠化发生的严重程度,也要能体现石漠化土地的成因和岩性地貌等地质背景对生态学过程的影响,因此,作者提出以“土地利用类型+植被+岩性+地貌+石漠化程度”对人为加速石漠化过程中石漠化土地进行类型划分,以正确评价石漠化土地的生态环境价值。

RESEARCH DEVELOPMENT AND PROBLEMS OF KARST ROCKY DESERTIFICATION

Karst rocky desertification is a major kind of land desertification.The vulnerability of karst ecosystem determines the sensitivity to damage and the difficulty to restore the karst ecosystem,but there is no intrinsic relation between karst ecosystem vulnerability and the occurrence of karst rocky desertification.Karst rocky desertification is the effect of degradation of the karst ecosystem other than the absolute behaves of vulnerable karst ecosystem.Therefore,the karst rocky desertification should be artificially accelerating rocky desertification,and a kind of man-made desertification,but it is not neglectful of the control of natural conditions over karst ecosystem.The classification of rocky desertification land should indicate the seriousness,the origin of rocky desertification and the influence of geological conditions such as rock type and topography on karst ecological processes.Hence,the authors suggest that land-use patterns,vegetation,rock,soil,topography and rock-desertification degree should be taken as indicators to divide rock desertification land resulting from artificially accelerating rock desertification so as to evaluate the eco-environment value of rocky desertification land correctly.