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在Arc Gis 10.0平台下,构建了鄱阳湖生态经济区小流域土壤侵蚀SWAT模型。利用潭口和渡峰坑水文站的逐日径流、泥沙实测数据对模型进行了校准及验证,并分析了土壤侵蚀的时空分布特征。模型适用性评价结果(月径流:0.886 2≤R2≤0.967 6,0.81≤NSE≤0.87;月泥沙:0.837 4≤R2≤0.911,0.68≤NSE≤0.76)显示了良好的精度,表明建立的Arc SWAT2009模型适宜研究区的土壤侵蚀模拟。土壤侵蚀时空分布特征显示,1983-2012年汛期(4-8月)土壤侵蚀为全年的83.2%,说明强降雨是形成土壤侵蚀的主要原因;其中,87.3%的研究区面积处于微度或轻度侵蚀级别;且农业发达和城镇密集的地区土壤侵蚀强度较高,其侵蚀模数居前两位,表明人为活动可能是土壤侵蚀的重要因子之一。
Under the Arc Gis 10.0 platform, SWAT model of soil erosion in a small watershed of Poyang Lake Ecological Economic Zone was constructed. The model was calibrated and validated by daily runoff and sediment data from the mouth and the Shuifengkeng hydrological station, and the spatio-temporal distribution of soil erosion was analyzed. The results of model suitability evaluation (monthly runoff: 0.886 2≤R2≤0.967 6, 0.81≤NSE≤0.87; monthly sediment: 0.837 4≤R2≤0.911, 0.68≤NSE≤0.76) showed good accuracy, indicating that the established Arc SWAT2009 model is suitable for simulating soil erosion in the study area. The temporal and spatial distribution of soil erosion showed that soil erosion in flood season (April-August) from 1983 to 2012 was 83.2% of the annual total, indicating that heavy rainfall is the main reason for soil erosion. Among them, 87.3% Mild erosion level. In addition, the soil erosion intensity of developed areas and densely populated areas in urban areas is higher, and the top two erosion modes show that human activities may be one of the important factors of soil erosion.