基于小流域产流特征的磷流失关键源区识别

发布时间：2018-05-24 06:48

本文选题：流域 + 磷　；参考：《农业工程学报》2017年20期

【摘要】：以密云区石匣小流域为研究区,根据不同降雨类型,采用超渗产流机制的径流曲线模型(SCS-CN)和蓄满产流机制的变源曲线模型(CN-VSA)进行产流特征分析,并利用磷指数模型识别不同产流机制下石匣小流域的磷流失关键源区。结果表明:1)中雨量、高雨强的降雨类型导致的超渗产流机制,使流域的东部、南部土壤较为湿润的区域以及流域的东北部和西部的易产流的耕地区域产流量较高,产流量介于15~30 mm,产流面积约占整个流域面积的14.2%;北部林地区域产流量较低,产流量低于15 mm,产流面积约占整个流域面积的85.8%;2)低雨量、低雨强的降雨类型导致的蓄满产流机制,使流域几乎所有区域不出现产流,产流量低于15 mm的区域面积占比达99.9%;高雨量、中雨强降雨类型导致的蓄满产流机制,使水库及流域水系周围产流量最高,产流量高于30 mm,其区域面积占14.6%、产流量介于15~30 mm之间的区域面积占17.7%、产流量低于15 mm的区域面积占67.7%;3)该研究区土壤侵蚀程度较弱,部分地区产流量较高,存在较高产流风险;4)超渗产流机制下,石匣小流域南部有磷流失风险,约占1.4%的面积;蓄满产流机制下,石匣小流域南部及北部有磷流失风险,约占2.3%的面积,蓄满产流机制下的磷流失风险较大。总体来说,石匣小流域磷流失风险较低,研究区域的南部靠近密云水库附近的区域为磷流失关键源区,需重点治理。
[Abstract]:According to the different rainfall types, the runoff curve model of superosmotic runoff mechanism (SCS-CNN) and the variable source curve model (CN-VSA-CN-VSA) were used to analyze the runoff characteristics of Shixai small watershed in Miyun area. Phosphorus index model was used to identify the key sources of phosphorus loss in Shixia small watershed under different runoff mechanisms. The results show that the mechanism of overosmotic runoff caused by moderate rainfall and heavy rainfall makes the runoff yield higher in the eastern part of the basin, the humid area in the southern part of the basin, and the easy runoff producing cultivated land in the northeast and west of the basin. The runoff yield is between 1530 mm and about 14.2mm of the whole watershed area, and the runoff production rate is lower in the northern woodland area, which is less than 15mm, and the runoff area accounts for 85.8 mm of the whole basin area. So that almost all areas of the basin do not produce runoff, the area of the area with output less than 15 mm accounts for 99.9% of Prida, and the mechanism of runoff accumulation caused by the type of high rainfall, moderate rain and strong rainfall makes the maximum yield and discharge around the reservoir and the river system in the basin. The area of yield and discharge is higher than 30 mm, the area is 14.6mm, the area of production flow is between 1530 mm and 17.7 mm, and the area with yield less than 15 mm accounts for 67.7%) the degree of soil erosion in this study area is relatively weak, and the yield and discharge in some areas are relatively high. The risk of phosphorus loss is 1.4% in the south of Shixia small watershed, and about 2.3% in the south and north of the small basin under the mechanism of high runoff yield. The risk of phosphorus loss is 1.4% in the south of Shixia small watershed, and about 1.4% in the south of Shijiao small watershed, and the risk of phosphorus loss in the south and north of Shijiao small watershed is about 2.3% under the mechanism of overflowing. The risk of phosphorus loss is higher under the mechanism of full runoff storage. In general, the risk of phosphorus loss in Shixai small watershed is low, and the area near Miyun Reservoir in the south of the study area is the key source area of phosphorus loss.
【作者单位】：首都师范大学资源环境与旅游学院;
【基金】：国家自然科学基金项目(41271495) 英国牛顿基金项目(BB/N013484/1) 首都师范大学研究生学术创新重点项目
【分类号】：S157.1

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