应用ARC／INFO预测芋子沟小流域土壤侵蚀量的研究

依据实地调查资料及相关图形资料 ,建立了芋子沟小流域地理数据库。在地理信息系统 ARC/ INFO支持下 ,根据通用土壤流失方程式 ( USL E)对数据库实施运算操作 ,预测了芋子沟小流域土壤侵蚀量。结果表明 ,芋子沟小流域年平均输沙模数为 3 893 .3 8t/ km2 ,侵蚀强度属中度 ;占流域面积 2 9.4 8%的坡耕地产沙量占流域总产沙量的 81.98% ,占流域面积 69.5 2 %的其它地类对流域土壤侵蚀量的贡献率仅为 18.0 2 % ,坡耕地年均土壤侵蚀量为 10 82 6.5 4 t/ km2 ,属于极强度侵蚀。坡耕地是芋子沟小流域水土流失的策源地 ,小流域水土流失治理的关键是实现流域内坡耕地的合理利用。

Supplying Geographical Information System ARC/INFO to Predict Soil Erosion of Watershed

The method of supplying geographical information system ARC/INFO to predict soi l erosion amount of watershed was probed. Based on the field survey,the geograp hical data base of Yuzigou small watershed was builded and the method of calcula ting the value of factors of USLE was studied. By the support of ARC/INFO ge ographical information system and integration of GIS and USLE,the soil erosion amount of Yuzigou small watershed was predicted. Results showed that the annua l average soil erosion amount was 3 893.38 t/km~2 and it belonged to middle deg ree erosion in Yuzigou small watershed;but the erosion amount of sloping land whose area accounted for 29.48% of the total area accounted for 81.98% of the total soil erosion amount of Yuzigou small watershed;the annual average soil er osion amount of sloping land was 10 826.54 t/km~2 and belonged to extremely st rong erosion. Results made clear that sloping land was the source of soil and w ater loss in Yuzigou small watershed and the key of harnessing soil and water l oss in watershed was that sloping land was rationally utilized.