中国南方典型喀斯特区石漠化与水土流失的空间耦合性:以关岭县为例

Spatial Coupling between Rocky Desertification and Soil Erosion in Guanling County,a Typical Karst Area in Southern China

为探明不同坡度下石漠化与水土流失的空间耦合性,为南方典型喀斯特区水土流失以及石漠化的生态治理提供科学依据,以关岭县2010年的水土流失及石漠化数据为基础,运用ARCGIS中的耦合性分析模型,获取各坡度等级下水土流失与石漠化的分布情况。结果表明:坡度<35°时,石漠化主要发生在水土流失微度侵蚀与轻度侵蚀区,水土流失主要发生在无石漠化与轻度石漠化区;坡度>35°时,石漠化主要发生在水土流失微度侵蚀与中度侵蚀区,水土流失主要发生在潜在石漠化与轻度石漠化区。在不同坡度下,喀斯特区石漠化等级(水土流失等级)的变化并不一定呈现相应的水土流失等级(石漠化等级)的变化,石漠化发生存在明显的滞后性。

The distribution of soil erosion and rocky desertification under different slopes was analyzed by the coupling model in AGCGIS based on the data of soil erosion and rocky desertification in Guanling County in 2010 to explore the spatial coupling between rocky desertification and soil erosion under different slopes and provide the scientific basis for ecological control of soil erosion and rocky desertification in the typical karst area in Southern China. Results： Rocky desertification occurs mainly in soil erosion areas with mired and mild erosion degree and soil erosion occurs in the areas without rocky desertification and with mild rocky desertification mainly when the slope is less than 35°. Rocky desertification occurs mainly in soil erosion areas with mired and moderate erosion degree and soil erosion occurs in the areas with potential and mild rocky desertification mainly when the slope is more than 35°. The variation of rocky desertification grade （soil erosion grade） is not in accordance with the corresponding variation of soil erosion grade （rocky desertification grade） in karst areas sometimes under different slopes, which indicates that the occurrence of rocky desertification is of obvious lagging behind.