土壤与养分流失综合监测方法在密云水库流域的应用

土壤与养分流失综合监测方法是根据通用流失方程的基本原理，在对我国中东部南北不同环境条件下大量周年实测数据的统计、分析基础上建立的适合我国南北地区的水土流失与面源污染一体化定量监测方法。本研究采用该方法对密云水库流域2001年度的土壤和氮素养分流失的空间分布，不同土地利用方式对土壤和氮素养分流失的影响，以及泥沙、养分的入库量进行了系统的监测，且利用水文站的实测数据对监测结果进行检验。结果显示，该监测方法对土壤和氮素流失监测的相对误差分别为2.75%~19.63%和-18.78%，监测效果较好。该监测方法具有技术先进、方便、实用、可更新性强和效果好的诸多特点，在我国现有相关资料积累条件下，适用范围较广。随着相关研究的进一步深入，该监测方法可通过改进满足更高时空监测需求，具有较好的应用前景。

Application of Integrated Method to Assessment of Soil and Nutrient Losses in Miyun Reservoir Basin

Based on the universal soil loss equation(USLE) and the revised universal soil loss equation ( RUSLE), integrated monitoring method for assessment of soil and nutrients losses has been calibrated by statistics of the data from runoff experiment plots and hydrological monitoring stations in the provinces of Shandong, Jiangsu, Fujian, Jiangxi and Hebe in China an area of more than 200 thousand km2. In this paper, the method was used for the assessment of soil and nitrogen losses in 2001in Miyun Reservoir Basin(115°25′E~117°35′E , 40°20′N~41°37′N), which possess an area of 15 365 km2 and is located in Hebei province. The spatial distribution of soil and nitrogen losses was calculated by GIS,RS and GPS technology and models, and the sand and nitrogen delivering ratios were also calculated. The accuracy of the monitoring method was tested by comparing the simulated values with that observed by hydrological monitoring station for the sediment and nitrogen delivered out off the catchment. The total simulated soil and nitrogen loss of Miyun Reservoir basin in 2001 was 14 617 782.10 t/a and 19 527.90 t/a respectively, and the sediment and nitrogen delivered into the reservoir was 634 332.80 t/a and 612.97 t/a respectively. The test showed the relative error of the simulated values with that observed by hydrological monitoring station was 2.75%~19.63% and 18.78% for sediment and nitrogen delivered into the reservoir in 2001 respectively. Because of its preferable accuracy, convenience, timesaving, easy for updating, the integrated monitoring method for the assessment of soil and nutrients losses is prospective for application in the erosive regions. 