黄河北岸灌区内河流天然文岩渠生态流量探讨

Study on Ecological Flow of the Tianran-Wenyan Channel in the Irrigation Area in the North Bank of the Yellow River

以河南省北部引黄灌区内天然文岩渠为研究对象,通过分析对比国内外有关河道内生态需水量的研究方法,采用较适宜表现河流年内丰枯变化过程的改进逐月频率法,计算逐月不同保证率（50%、70%、75%、80%、85%、90%）条件下的河流生态流量,同时采用Tennant 法、90%保证率最枯连续7 日平均流量法（7Q10 法）、逐月最小生态径流计算法以及多年逐月平均流量法进行对比.使用Tennant 生态环境状况评价等级标准对多种计算结果进行评价,得出年内逐月最小生态流量：天然文岩渠丰水期（6-10 月）最小生态流量为多年同期平均流量的65% ～80%;枯水期（11 月一次年5 月）最小生态流量为多年同期平均流量的40% ～50%.

Selecting Tianran-Wenyan channel of the Yellow River irrigation area in the north of Henan Province as study site,through comparing and analyzing the research methods of rivers ecological water demand at home and abroad,this paper adopted improved monthly frequency computation method that a suitable method to better reflect rivers flow changes during the year to calculate the river ecological flow under the different guarantee rates( 50%,70%,75%,80%,85% and 90%). At the same time,it adopted calculation results of Tennant method,the minimum average monthly flow in the last ten years method( 7Q10 method),the month-by-month minimum ecological flow calculation method and the month-by-month average flow for years to compare and reference. According to the Tennant ecological environment evaluation grade standard to evaluate all kinds of calculation results,it revised the value of the month-by-month minimum ecological flow.The results show that the minimum ecological flow of the Tianran-Wenyan Channel is 65% to 80% from June to October and 40% to 50%from November to following May of the average flow in the same period.