作者于八十年代中期实地考察了新安江上游的环境质量。本文对该流域的水土流失程度和形成原因进行了初步探讨。该流域存在有四种形成水土流失的潜在因素即地形地貌特殊,降雨集中且强度大、土垠质地低劣、温差变动幅度大。近三十几年来,该流域水土流失日益加剧,这主要是流域的植被、土垠、水分三个生态因子失去了动态平衡,生态环境遭到了严重的破坏。 In the mid-1980s, the author inspected the environmental quality in the upper reaches of Xin’anjiang River. In this paper, the extent of soil and water loss and the reasons for its formation in this basin are discussed. There are four potential causes of water and soil loss in the basin, that is, the topography is special, the rainfall is concentrated and strong, the texture of soil is poor, and the variation range of temperature is large. In the recent three decades, the soil and water loss in the basin has been aggravating day by day. This is mainly due to the loss of the dynamic balance of the three ecological factors such as vegetation, soil eave and water in the watershed and the serious damage to the ecological environment.