Determining the Ecologically Sustainable River Flow Using the Multiple Species Habitat Suitability Model

【Objective】 The ecological functions of a river are manifold; and how to determine river flow rates which are ecologically sustainable is important but not trivial. In this paper, we proposed a new approach to model river habitat. 【Method】 The model is based on multiple indicator species and considers their competition as well as the consequence for growth of individual species. The model is constructed based on the fuzzy logic method to establish the quantitative relationship between river habitat quality and runoff conditions. We applied the model to the Xinyang section of the Shihe River. 【Result】 The sustainable ecological water flow in this section of the river calculated by the model is 160~260 m3/s, and the minimum ecological flow rate is 60 m3/s. The result interval is stricter than that calculated from the single indicator species model using crucian carp as the indicator. 【Conclusion】 Multiple indicator species model we proposed for determining ecologically sustainable river flow is robust and accurate. It can be used for designing sustainable development and utilization of river water resources.