全国不同区域河流生态基流达标现状与不达标原因EI北大核心CSCD

为系统认识我国不同区域河流生态基流达标现状,针对全国各大流域90个已确定生态基流目标的主要河流控制断面,基于2009—2018年实测流量资料,综合月均流量、日均流量2种不同达标评估方法,对断面生态基流达标现状进行了评估,并初步剖析了不同区域不达标原因,提出了调控保障建议。结果表明:按照月均流量达标评价,全国主要河流断面生态基流达标率为73.3%;采用日均流量达标评价方法,全国主要河流断面生态基流达标率显著下降,仅为26.7%。东北、西南地区生态基流达标率好于其他区域,黄淮海地区的淮河水系、沂沭泗水系及东南沿海地区的西江水系为本次评价中生态基流达标率最差的3个水系。全国层面,取用水总量高、取用水季节性冲突、水利工程不合理调度等人为因素是生态基流不达标的主要原因,占比62.3%。

Current situation of compliance of river ecological base flow and noncompliance reasons in different regions of China

In order to systematically understand the current situation of river ecological base flow in different regions of China, two different compliance assessment methods of monthly average flow and daily average flow were used to evaluate the current situation of the ecological base flow of river cross-sections, and the noncompliance reasons in different regions were preliminarily analyzed based on 90 main river cross-sections with established ecological base flow targets and the flow data in the period from 2009 to 2018. Regulation and guarantee measures were put forward. The results showed that the ecological base flow compliance rate of main river cross-sections in China was 73. 3% when the monthly average flow was taken as the evaluation unit. The rate dropped significantly to only 26. 7% when the daily average flow was taken as the evaluation unit. The compliance rates of ecological base flow in the northeastern and southwestern regions were better than other regions. The Huaihe River system and Yi-Shu-Si River system from the Huang-Huai-Hai Region, and the Xijiang River system from the Southeast coastal region were the three river systems with the worst ecological base flow compliance rates in the evaluation. Human activities, including high total water withdrawal, seasonal conflicts in water withdrawal, and irrational dispatch of water conservancy projects, were the main noncompliance reasons, accounting for 62. 3%.