暴雨径流对流域不同土地利用土壤氮磷流失的影响  

An Experiment on Influence of Storm on Nitrogen Loss and Phosphorus Loss under Different Land Use in River Basin

作　　者：陈志良[1,2] 程炯[1] 刘平[1] 彭晓春[2] 许振成[2] 吴志峰[1] 

机构地区：[1]广东省生态环境与土壤研究所,广州510650 [2]环境保护部华南环境科学研究所,广州510655

出　　处：《水土保持学报》2008年第5期30-33,共4页Journal of Soil and Water Conservation

基　　金：国家自然科学基金项目(40571164)

摘　　要：以广州流溪河流域内土地利用类型齐全、相对闭合的小流域——新田小流域为例,分析了不同暴雨径流过程与土地利用对氮、磷流失的影响,结果表明:(1)林地氮磷的流失较少,说明植被覆盖可以有效减少土壤侵蚀、总磷和总氮的流失;而坡耕地是氮磷流失的重要策源地,说明人类活动对土壤氮磷的干扰很大。(2)流域径流中氮、磷的流失形态分为可溶态和颗粒态,径流中流失是以颗粒态形式流失,即氮磷是以泥沙结合形式流失的;径流中氮素主要是以可溶态氮流失的。(3)氮磷浓度在降雨初期与末期最大。(4)降雨径流是引起土壤氮磷损失的重要原因,但不同的土地利用方式是造成土壤氮磷流失的本质因素,因此在降雨前应特别注意减少和避免那些会加剧土壤侵蚀和磷流失的农事活动。Land use and storm are key roles of soil erosion, which is an important source of nonpomt pollution. Different intensity of storm and land use pattern may be great impacted on losses of nitrogen and phospheres. This paper was illustrated the relation between different intensity of storm and land use pattern influences on nitrogen and phosphorus losses. We selected a representative and relatively closed watershed with all kinds of land use pattern in Liuxihe river basin to conduct the present study. From May to September of 2006, series of water samples were collected in the study area-watershed monitor spots in each storm event, at the same time, flow rate and water depth were also measured. Six indicators of water quality were measured, such as total dissolved phosphorus （TDP）, total nitrogen （TP）, chemical oxygen demand （COD）, ammonia nitrogen （NH4^＋ -N）, total nitrogen （TN） and nitrate nitrogen. The results are as follow： ① The nitrogen and phosphorus loss of forest is least, which indicated that vegetation can suspend the soil erosion and nitrogen and phosphorus loss effectively. However, slope farmland was an important source of nonpoint pollution, this phenomenon suggests that human activity be a key role on nitrogen and phosphorus loss, in the investigation, we found that many farmers plant crop on slope land and fertilize with amount of nitrogenous and phosporus fertilizer. ② We can assort solid and dissolved form of nitrogenous and phosporus, and most loss of nitrogenous is as dissolved form,while most loss of phosphorus is as solid. ③ The highest concentration of TP and TN appear at the time of beginning and end of storm, which is different from other studies. ④ Human being acts as an important role to impact on the nitrogenous and phosporus loss, while, storm places a premium on these. So, in order to prevent nonpoint pollution, it is necessary to reduce the human interferes before rain.

关 键 词：暴雨径流 土地利用 氮流失 磷流失 新田小流域 

分 类 号：S151.9[农业科学—土壤学]