鲁中南山地丘陵区土壤侵蚀强度景观格局的动态变化

Dynamic changes of landscape pattern of soil erosion intensity in hilly area of central-south Shandong Province, China

以鲁中南山地丘陵区为研究区,以TM影像和地形图为源数据,借助GIS和RS技术,获取1986、1995和2004年土壤侵蚀强度数据,分析鲁中南山地丘陵区近20年来土壤侵蚀强度景观格局动态变化。结果表明:微度和轻度土壤侵蚀面积增加,而中度以上土壤侵蚀面积具有明显减小的趋势,其中轻度、强度、极强度和剧烈4种土壤侵蚀类型的面积变化比较显著;较低级别(微度、轻度和中度)土壤侵蚀强度转移率较小,较高级别(强度、极强度和剧烈)的土壤侵蚀强度转移程度较大;在景观水平上,1986—1995年斑块数量和景观形状指数增加,蔓延度指数下降,表明这期间斑块破碎度增加,连接度降低,形状变得更为复杂;而1995—2004年各指数变化趋势恰好相反。

By using Landsat TM images and topographic maps as the data sources, and with the supports of GIS and RS techniques, the data of soil erosion intensity in hilly area of central-south Shandong Province in 1986, 1995, and 2004 were collected, and the recent 20 years dynamic changes of the landscape pattern of soil erosion intensity in this area were analyzed. In the study area, the areas with minute and slight soil erosion increased, while those with moderate to severe soil erosion had an obvious decreasing trend, in which, slight, intense, very intense, and severe soil erosion areas had significant changes. The transfer rate of lower level （minimal, slight, and moderate） soil erosion intensity was relatively low, but the higher level （intense, very intense, and severe） soil erosion intensity transferred greatly. At landscape level, the patch number and landscape shape index from 1986 to 1995 increased while the contagion index decreased, which indicated that in this period, the patch fragmentation was increased but the connection degree was decreased, and the shape became more complex. From 1995 to 2004, an opposite trend was observed.