江西兴国土壤侵蚀动态的研究

Soil erosion in Xingguo County of Jiangxi Province

利用遥感、GIS和灰色预测模型研究了中国南方典型区土壤侵蚀的状况 .结果表明 ,从 1958— 1988年 ,兴国县的水土流失面积和侵蚀量分别下降了 19 0 9%和 43 0 5% ;灰色预测显示无明显侵蚀区水土流失面积由 1988年的818 0 4km达到 1995年的 12 76 69km2 ;总侵蚀量由 60 7 2 1× 10 4 t a下降到 472 12× 10 4 t a .比较不同土地利用类型的产沙模数显示 ,林地的产沙模数最小 ,为 177 16～ 187 75t (km2 ·a) ,裸地最大 ,为 10 62 6 76～ 112 65 48t (km2 ·a) .由此证明 ,高覆盖植被可以减低水土流失 。

The soil erosion in typical areas of south China was studied based on remote sensing, GIS and gray forecasting model. The results of survey on Xingguo Count y showed that the soil erosion area and annual soil erosion amount decreased by 19 09% and 43 05% respectively from 1958 to 1988. The results of gray forecastin g model revealed that the soil and water loss area increased from 818 04 km 2 in 1988 to 1 276 69 km 2 in 1995 in non-erosion areas, in the meantime, total soil erosion amount decre ased from 607 21×10 4 t/a in 1988 to 472 12×10 4 t/a in 1995. Compared wit h the different landuse types, the soil loss modulus of forest was the lowest ( 1 77 16～187 75 t/(km 2·a)); on the contrary,that of the bare land was the hig hest ( 10 626 76 ～ 11 265 48 t/(km 2·a)). Thus it indicated that high vegetation coverage can decrease the soil and water loss,and the biological mea sure is the ef fective method to control soil erosion.