西吉县黄土丘陵沟壑区小流域土壤流失量预报方程

木文在实地测量水库、塘坝淤积量和全面调查影响因子的基础上,利用计算机对获得的大量资料进行了统计分析,建立了黄土丘陵沟壑区小流域土壤侵蚀数学模型。研究结果表明:根据影响土壤侵蚀的主导因子建立的小流域年土壤流失量预报方程,具有较高的精度。预报方程比较客观地反映了各个影响因子对小流域土壤侵蚀的综合作用,它不仅能够根据给定的条件,估算流域内过去和现在的年土壤流失量,而且能够预报未来某一降雨水平的年土壤流失量,同时利用本方程对流域土壤流失量及其影响因子进行定量分析,这对于判定小流域治理总体规划、布设各项治理措施、进行流域管理以及有效地控制土壤侵蚀等提供了可靠依据。 本文研究的结果,已在西吉县防护林工程建设和全县水土流失综合治理中广泛应用,并被 WFP/FAO 中期评价组有关国外专家所采用。

PREDICTION EQUATION OF SMALL WATERSHED SOIL EROSION ON THE LOESSAL GULLY HILL AREA

Based on the silt measure of reservoirs and ponds and the investigation ot all factors concerned, after the statistical analyses of all informations, this paper presents a mathematical erosion model used for the small watershed in the loess areas. The research results show: the prediction equation for annual soil loss in a small watershed which is based on the analyses of the leading factors has a higher precision. The equation objectively reflects the comprehensive roles between the concerned factors. It not only calculates, according to the given-data, both previous and present soil loss each year, but predicts the annual soil loss at a certain rainfall level in .the future. In the meantime, this paper more comprehensively makes quantitative analyses of soil erosion law in the loess hill area and indicates the interactions and relationships between the factors influencing soil loss. So it gives the reliable functions to establish a watershed management plan and to control soil erosion with the different efforts.The research results have been applied to the local areas and adopted by the foreign specialists of WEP/FAO evaluation mission.