花岗岩风化壳土地退化及其危害

Land Degradation in Granite Weathering Crust Region and Its Negative Effects

土地退化是持续发展中的重要环境问题之一。该文讨论了花岗岩风化壳土地退化特点、成因及危害，给出了退化土地评价指标。

Land degradation,an important sustainable development issue,is defined as this:the diminution or destruc-tion of the biological or economic potential caused by one or a combination of processes actiong on t he la nd.Theprocesses include water erosion,wind erosion,and longterm reduction in the amount of natural regetation.There is severe water erosion in the granite weathering crust area in southern China. As a result of water ero-sion,desert-like landscape appears in the place such as badlands,deterioration of soil properties and vegetationdegradation. For example,27%of total area in Wuhua county,Guangdong Province,has suffered from badlands.In consideration of the badlands that are mainly landscape in the process of degradation,in which vegetation cover.age,density of gully and weathering layer condition as well as erosion type can be regards as the indicator to assessIand degradation,Finally,this paper discusses the negative effects of land degradation on social and environment.They include destruction of land resource,silation of reservoirs and reducement of plant grouth etc。