基于改进的Tennant法的大凌河生态基流计算

Calculation of Ecological Base Flow in Dalinghe River Based on Improved Tennant Method

针对传统的Tennant法计算河流生态基流不能反映河流水量季节性变化的问题,提出引入季节修正系数并利用中位数代替平均数计算多年平均流量的改进Tennant法,避免了极端数据对统计数据的影响,在水文数据选取中舍弃了人为影响较大年份的数据资料,减小了人类活动对计算结果的干扰。以大凌河生态基流计算为例,改进的Tennant法与传统方法相比,所计算的河流生态基流小于后者,与实际情况更为接近。

In order to solve the problem that calculation of river ecological base flow with traditional Tennant method can not reflect the seasonal variation of river water yield, an improved Tennant method is proposed to calculate average annual discharge by introducing seasonal correction coefficient and using median instead of mean value. The proposed method has some advantages, such as avoiding the influence of extreme data on the statistical data, abandoning artificial influence year＇s data in selection of hydrological data, and reducing the interference of human activities on the calculation results. Taking ecological base flow calculation in Dalinghe River as an example, the calculation of river ecological base flow with improved Tennant method is less than that of the traditional method, which is more consistent with the actual situation.