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目前我国水土流失分布面积尚无准确的数字,土壤侵蚀强度分级还缺少统一的标准,而河流输沙量方面的观测资料比较系统。由于河流输沙量与流域内的水土流失成正相关,所以,我们根据河流输沙量的变化情况,来进行水土流失趋势预测。在多雨年和少雨年,年输沙量相差悬殊,单纯根据年输沙量的大小,很难准确判断出流域内水土流失的变化趋势。为此,我们建立了河流输沙量与流域内影响水土流失各主要因素之间的相关方程,用以进行水土流失趋势预测。根据近年来水土保持工作快速发展的形势预测出,从现在起到2000年,我国水土流失有减弱的趋势,并提出水土保持对策。
At present, there is still no accurate figure for the distribution of soil and water loss in our country, and there is a lack of uniform standards for the classification of soil erosion intensity. The observation data on river sediment discharge is relatively systematic. Because of the positive correlation between the amount of sediment and the amount of soil and water loss in the river basin, we make a prediction of the trend of soil and water loss based on the change of sediment discharge. In the rainy years and the years when there is a great difference in annual sediment discharge, it is difficult to accurately determine the trend of soil and water loss in the basin based on the annual sediment discharge. To this end, we have established a correlation equation between the amount of sediment discharged from the river and the major factors influencing water and soil loss in the basin, which are used to predict the trend of soil and water loss. According to the rapid development of soil and water conservation in recent years, it predicts that from now on to 2000, soil erosion in China will have a tendency of weakening and the countermeasures for soil and water conservation will be put forward.