赣江下游河道适宜生态需水量计算

Calculation of suitable ecological flow requirement in the lower reaches of Ganjiang river

受气候变化及人类活动的影响,赣江下游河道生产生活与生态用水的矛盾日益增加。本研究采用Tennant法和生态流量阈值法分别计算外洲断面生态需水量,并采用基于四大家鱼为生态保护目标的湿周法进行筛选比对,确定赣江下游适宜和较适宜的生态需水过程。结果表明:Tennant法和生态流量阈值法计算得到的年均适宜生态需水量分别为845.44m3/s、1041.30m3/s,占外洲断面多年平均径流的40%左右;年均较适宜生态需水量为626.60m3/s、561.16m3/s,占外洲断面多年平均径流的27%左右,为赣江下游适宜生态需水量的预留提供依据。

Under the influence of climate change and human activities,the contradiction between production and living and ecological water consumption in the lower reaches of Ganjiang river is increasing day by day.In this study,the Tennant method and ecological flow threshold method were used to calculate the ecological water requirement of the outer continent section,and wetted perimeter method based on the ecological protection objective of four fish was used for screening and comparison to determine the appropriate and relative appropriate ecological water requirement process in the lower reaches of Ganjiang river.The results show that the average annual optimum ecological water requirement calculated by Tennant method and ecological flow threshold method is 845.44 m3/s and 1041.30m3/s respectively,accounting for about 40%of the annual average runoff for years in the outer continent section.The average annual optimum ecological water requirements are 626.60 m3/s and 561.16 m3/s calculated by those two methods respectively,accounting for about 27%of the annual average runoff for years in the outer continental section.It provides a basis for the reservation of the optimum ecological water requirements in the lower reaches of Ganjiang river.