雨强和土地利用类型对豫西南山区产流产沙的影响

Effects of rainfall intensity and land use on flow volume and sediment yield in Southwest Coteau of Henan Province

为掌握雨强和土地利用方式对丹江口水库水源区水土流失的影响,采用室内人工模拟降雨试验,采集豫西南山区5种常见土地利用类型的表层土壤,研究其在6种雨强下的水土流失规律,结果表明:雨强对不同土地利用类型的产流产沙影响显著,5种土地利用类型土壤中的产流产沙量与雨强均呈幂函数增加,说明雨强越大,相应的产流产沙量也越多;6种雨强的平均产流量、产沙量均为坡耕地>梯田>荒草地>乔木林>灌草地,这是因为林地和灌草地土壤具有良好的保水保土效果,其产流产沙量都小于其他土地类型.结论:在豫西南山区有必要开展坡改梯和退耕还林还草工程,以减少用地中的水土流失,确保丹江口水库水质.

Artificial rainfall experiments were adopted to master the effects of rainfall intensity and land use on soil and water loss in Danjiangkou reservoir catchment areas and five kinds of common land use types of topsoil were collected to study the rule of soil erosion under six kinds of rainfall intensity. The results show that the rainfall intensity significantly influences the runoff and sediment yield in different land use types, either average flow or sediment yield in the five kinds of soils was power function with rainfall in- tensity, which explained the greater of rainfall intensity the more flow and sediment yield correspondingly. The order of average flow and sediment yield were both slope cropland〉terrace〉waste grassland〉arbor woodland〉shrubby grassland because of good effects of soil and water conservation for woodland and shrubby grassland. It＇s necessary to carry out the policy of terracing of cultivated sloping land and retur- ning farmland to forest and grass to reduce water and soil loss of land use, so as to ensure the water quality of Danjiangkou Reservoir.