我国水力侵蚀抽样调查方法

水力侵蚀普查是2010-2012年第1次全国水利普查水土保持情况普查的重要内容之一,抽样调查是本次水力侵蚀普查的主要方法.野外抽样调查单元依据不同侵蚀类型区和各省份实际情况相结合的原则布设:在全国按统一网格布局,按一定密度抽样,获得野外调查单元的位置；以第4层网格(1 km×1 km)为基础,在平原区以1 km×1 km网格、在丘陵区和山区以0.2～3.0 km2的小流域作为野外调查单元.综合分析降雨、地形、土地利用和水土保持措施等影响水力侵蚀的因子,利用中国土壤流失方程来评价水力侵蚀强度,获得水力侵蚀的分布、面积与强度,为国家水土保持与生态建设提供决策依据.水力侵蚀抽样调查方法研究对全面调查和科学评价水力侵蚀现状、发展趋势和预测预报具有重要意义.

Sampling program of water erosion inventory in the first national water resource survey

The water erosion inventory is an important part of the first national water resource survey in 2010-2012.Sampling investigation is the main method of the water erosion inventory.Field sampling units were designed according to erosion types and actual situation of each province： Firstly,the whole country was divided into grids and sampling was complemented according to a certain density to obtain the location of the field survey units;secondly,on the basis of the fourth layer grids,the grid with the area of 1 km×1 km in the plain area or the small watershed with area from 0.2 to 3.0 km2 in the mountainous area was selected for observation.After comprehensive analysis of impact factors including rainfall,terrain,landuse and soil conservation practice the soil erosion intensity was computed by Chinese Soil Loss Equation to evaluate the distribution,area and intensity of water erosion.The evaluation results will provide guidance and decision-making for national water and soil conservation and ecological construction.This sampling method research is of great significance for comprehensive investigation and scientific evaluation of water erosion＇s present situation,trends of development and forecasting.