三峡库区紫色土坡地典型暴雨径流氮磷流失特征  

Characteristics of Typical Rainstorm-runoff Nitrogen and Phosphorus Loss on Purple Soil Slope in Three Gorges Reservoir Area

作　　者：王甜 肖文发[1,2] 黄志霖[1,2] 曾立雄[1,2] WANG Tian;XIAO Wen-fa;HUANG Zhi-lin;ZENG Li-xiong(Institute of Forest Ecology,Environment and Nature Conservation,Chinese Academy of Forestry/Key Laboratory of Forest Ecology and Environment of National Forestry and Grass Land Administration,Beijing 100091,China;Co-innovation Center for Sustainable For-estry in Southern China,Nanjing Forestry University,Nanjing 210037,China)

机构地区：[1]中国林业科学研究院森林生态环境与自然保护研究所/国家林业和草原局森林生态环境重点实验室,北京100091 [2]南京林业大学南方现代林业协同创新中心,江苏南京210037

出　　处：《生态与农村环境学报》2022年第3期367-374,共8页Journal of Ecology and Rural Environment

基　　金：国家重点研发计划(2017YFC0505301-1);国家自然科学基金(32171877)。

摘　　要：为研究暴雨径流过程中紫色土坡地土壤氮磷的迁移规律,利用坡地试验小区对三峡库区兰陵溪小流域2019年雨季降雨径流过程进行监测,选取6月22日(长历时均匀降雨)和8月3日(短历时强降雨)两场典型暴雨,分析暴雨特征对地表径流和壤中流以及随径流流失的氮磷的影响。结果表明:(1)两场暴雨事件中,受降雨特征影响,其径流量、径流历时、峰值流量和径流率都存在明显差异,且降雨过程中峰值雨强出现的时间对壤中流的产流时间有决定作用。(2)不同暴雨条件下地表径流和壤中流中氮磷浓度差异较大,主要受降雨量和峰值雨强影响,但与同时段降雨量呈负相关关系,与同时段径流量呈显著正相关关系。(3)土壤养分径流流失以TN流失为主,且氮磷流失量与径流流失量呈现显著正相关关系。6月22日和8月3日TN流失量分别为4.03和8.49 kg·hm^(-2),其中,壤中流贡献率分别为88.59%和85.51%;TP流失量分别为0.11和0.33 kg·hm^(-2),其中,以颗粒态形式流失占比分别为54.55%和60.61%。上述结果表明,短历时强降雨会造成更大的水土流失和养分流失,这为三峡库区农业面源污染的防控工作提供了参考依据。To study the movement of nitrogen(N) and phosphorus(P) on a purple soil slope during rainstorm runoff,the rainfall runoff process of Lanlingxi watershed in Three Gorges Reservoir Area was monitored in 2019 using a slope plot.Two rainstorms,typical of long-term uniform rainfall(June 22) and short-term heavy rainfall(August 3),were selected to analyze the impact of rainstorm characteristics on surface flow,interflow and N and P loss with runoff.The results show that:(1) there were significant differences in runoff,runoff duration,peak flow and runoff rate between the two rainstorm events.The time of peak rainfall intensity had a decisive effect on the interflow generation time.(2) Under different rainstorm conditions,the concentration of N and P in surface flow and interflow were significantly different.This was mainly affected by rainfall and peak rainfall intensity.The concentrations of N and P in runoff were negatively correlated with rainfall in the same period,and positively correlated with runoff in the same period.(3) Total N(TN) was the main form of soil nutrient runoff loss,and there was a significant positive correlation between N and P loss and runoff loss.On June 22 and August 3,TN loss was 4.03 and 8.49 kg·hm^(-2),respectively,in which the contribution rate of interflow was 88.59% and 85.51%,respectively.The total P(TP) loss was 0.11 and 0.33 kg·hm^(-2),respectively,of which the loss in granular form accounted for 54.55% and 60.61%,respectively.The results show that short-duration heavy rainfall caused greater soil erosion and nutrient loss.This provides a reference for the prevention and control of agricultural non-point source pollution in the Three Gorges Reservoir Area.

关 键 词：三峡库区 紫色土 暴雨类型 地表径流 壤中流 氮 磷 

分 类 号：X52[环境科学与工程—环境工程] S157.1[农业科学—土壤学]