Environmental flow process for the habitat demands of finless porpoise in the Tongling section of Yangtze River
Yangtze finless porpoise is an important species for indicating the health of the Yangtze River aquatic ecosystem.The environmental flow process based on habitat demands is key to study the environmental flows in the Yangtze River mainstream.In order to obtain environmental flows for the suitable habitat of Yangtze finless,the indicators of hydrologic alteration and range of variability approach were used to quantitatively evaluate the hydrological regimes changes of the Tongling section of Yangtze River.Using water depth and flow velocity as limiting factors,the optimal environmental flows for Yangtze finless porpoise was calculated by habitat simulation model.And the monthly environmental flow schemes were recommended combined the results of hydrologic methods.To comprehensively determine the environmental flow process,a high flow pulse from April to September was designed by considering the flow component characteristics during the breeding period.The results showed that the overall degree of hydrological alternation of the Tongling section has reached moderate change(49.74%),environmental flows components mainly include low flows and high pulse flows,and environmental flow events tended to be homogeneous.The optimal environmental flows for the Yangtze finless porpoise habitat were 19000～31100 m3/s,especially with the optimum values from 22500 to 28500 m3/s in dry season;while in range of 27000～31000 m3/s,35000～45000 m3/s,and 60000～62000 m3/s in wet season.When the flow value was higher than 39100 m3/s,its duration of at least 3 days was regarded as a high flow pulse event,and the initial value of small flood occurs when the upper limit of high flow pulse peak Q = 48000 m3/s.The results of this study can provide scientific data support for the habitat protection and ecological regulation of the Yangtze River finless porpoise,and provide technical support for effectively promoting the protection of the Yangtze River.
Environmental flowsYangtze finless porpoise protectionhydrological approachhabitat simulation approachTongling section of Yangtze River mainstream
万方数据
维普
