Comprehensive Evaluation of Scenario Schemes for Multi-objective Decision-making in River Ecological Restoration by Artificially Recharging River

Abstract

Worldwide, many rivers experience serious water deficiency to such a degree that artificial water recharge is the only option for their ecological restoration. In this contribution, we present a framework for comprehensively evaluating multi-objective scenarios to support decision-making for effective river ecological restoration by artificial recharge. First, we developed an evaluation index system, comprising eight typical evaluation indices, to allow a comprehensive assessment of river ecological restoration. A multi-level and stepwise weighting method was then proposed to determine the final weights of those different evaluation indices for calculating and achieving the overall objective of river ecological restoration. Finally, a comprehensive framework was developed in two steps. First, we integrated the proposed index system and the weighting method using a principal component projection approach. We then tested the proposed framework in a case study to support decision-making for the ecological restoration of the Yongding River using artificially recharged and recycled water. The case study demonstrated that the comprehensive evaluation index system was rational, and verified the advantages and feasibility of the proposed weighting method. In particular, it indicated that the proposed framework was reasonable and effective for evaluating river ecological restoration with artificial river recharge. It was also capable of identifying optimal restoration scenarios from a range of scenarios generated by the newly developed decision-support system.