为了拓宽年内展布计算法的适用范围, 针对我国北方河道季节性明显的特点, 对该方法进行改进。在原方法 的基础上, 将同期均值比修改为特枯年( P= 90% ) 河道年径流量与多年平均径流量的比值, 结合多年月均径流量进 行河道内基本生态需水量计算。以弥河谭家坊水文断面为例, 计算河道内基本生态需水量, 并与 T ennant 法标准及 我国常用的水文学方法以及改进前的年内展布计算法作对比。结果表明, 在一般用水期和鱼类产卵育幼期, 改进的 年内展布计算法结果都能够满足维持河道基本生态功能的要求, 更为合理, 证实该方法既继承了原方法能够体现河 道年内径流总体过程和变化特征的特点, 又能够适用于季节性明显的河道, 适用于河道内基本生态需水量的计算。

In or der t o broaden the applicability o f the dynamic calculatio n method, w e impro ved the method in v iew of the obvious seasonality of northern riv ers in China. On the basis of the o rig inal method, w e substituted the percent o f the av erag e flow in the same periods w ith t he rat io of the annua l runo ff in ex treme droug ht y ea rs ( P= 90% ) to the multi2year aver age runoff, and used the mult i2year averag e mo nthly runoff for calculation of the instr eam basic ecolog ical w ater demand. Taking the hydrolog ical sectio n of T anjiafang as a case study, w e calculated the basic ecolog ical water demand in the river and compared the metho d with the T ennant met ho d and other methods. The results show ed that the calculation results o f the improv ed metho d wer e r easo nable and could meet the r equir ement of mainta ining the basic ecolo gica l function of t he river in the general w ater using period and the spaw ning and nursing period. This method has inherited the strengt hs of t he o rig inal method in show ing the ov erall r unoff pr ocess and the chang ing char acteristics of the river co urse during a y ear. It can be applied to riv ers w ith o bv ious seasonalit y. This metho d is suitable fo r the calculat ion of instr eam basic ecolo g ical w ater demand.

‘十二五’ 国家科技支撑计划项目( 2015BAB07B02) ; 山东省重大水利科研与技术推广专项资助项目( SDS LKY201501; SDSLKY201222)