Baseflow:Potential Pathway Underlying a High Nitrogen Concentra-tion in a Less-rainy WatershedTaking Chaohe River Basin of China as an Example  

作　　者：JIN Zhongtian TANG Shinan LIU Zhuoran CAO Qinyuan CHEN Dadi SHEN Zhenyao ZHAO Ye CHEN Lei 

机构地区：[1]State Key Laboratory of Water Environment Simulation,School of Environment,Beijing Normal University,Beijing 100875,China [2]General Institute of Water Resources and Hydropower Planning and Design,Ministry of Water Resources,Beijing 100120,China [3]Beijing Municipal Research Institute of Eco-Environmental Protection,Beijing 100037,China

出　　处：《Chinese Geographical Science》2024年第6期1032-1044,共13页中国地理科学（英文版）

基　　金：Under the auspices of the National Natural Science Foundation of China(No.52221003,42277044)。

摘　　要：Baseflow is one of the major pathways of runoff in hilly areas,and its contributions to surface water resources and pollutant loads cannot be ignored.In this study,based on water quantity and quality data from 1988 to 2019 in hilly and low rainfall watersheds,we focused on the impact of long-term baseflow on nitrogen load using the load allocation based on the baseflow separation method.We also constructed a nitrogen balance model for the Chaohe River Basin of China from 2012 to 2021 to analyze the nitrogen accumulation in the basin.We used the baseflow nitrogen load lag analysis method to study the lag characteristics of the baseflow discharge process and analyzed the response and periodicity of baseflow nitrogen to precipitation and soil accumulation using time delay analysis.The res-ults showed that the contribution rate of baseflow nitrogen reached 69%and showed a slight increasing trend from 1988 to 2019.The ef-fects of changes in precipitation and nitrogen accumulation on the baseflow contribution was observed after 1-2 and 2 yr,respectively.After nitrogen accumulation,it entered the river channel through baseflow,which was already the main and continuous source of nitro-gen in rivers in hilly areas.

关 键 词：BASEFLOW hilly aera nitrogen load lag response Chaohe River Basin China 

分 类 号：X522[环境科学与工程—环境工程]