基于水文学法的小流域生态流量研究

Study on Ecological Flow of Small Watershed Based on Hydrological Method

为评估确定小流域适宜的生态流量,以珠江流域清水河为例,通过Tennant法、Texas法、频率曲线法等6种水文学方法计算逐月生态流量,并进一步结合水文节律及生态流量保障率,对比枯、汛两个时期6种方法的优劣程度,获得最适宜小流域的生态流量计算方法来确定生态流量。结果表明,红旗水库断面生态流量在0.12~1.52 m^(3)/s之间,普者黑断面生态流量在0.30~4.95 m^(3)/s之间;水文节律拟合系数分别为0.993、0.998,生态流量保障率均处于良好水平,生态流量选取结果合理。研究结果可为类似全国小流域选取适宜计算方法确定生态流量提供参考。

To determine the appropriate ecological flow for small watershed assessment,taking Qingshui River in Pearl River Basin as an example,the monthly ecological flow was calculated by using six hydrological methods such as Tennant method,Texas method and frequency curve method.Furthermore,combined with hydrological rhythm and ecological flow guarantee rate,the advantages and disadvantages of the six methods were compared and analyzed in the dry and flood periods,and the most suitable ecological flow calculation method for small watershed was obtained to determine the ecological flow.The results show that the ecological flow of Hongqi Reservoir section is between 0.12-1.52 m^(3)/s,and the ecological flow of Puzhehei section is between 0.30-4.95 m^(3)/s.The fitting coefficients of hydrological rhythm are 0.993 and 0.998,respectively.The ecological flow guarantee rate is at a good level,and the ecological flow selection result is reasonable.The results can provide a reference for similar national small watersheds to select appropriate calculation method to determine the ecological flow.