A Wetland Network Design for Water Allocation Based on Environmental Flow Requirements

Abstract

Excessive water use with economic development has led to the shortage of environmental flow requirements (EFRs) for different wetlands in the past years, a number of wetlands become degraded or disappeared. A suitable water allocation used for wetland restoration has become focus in the field. This article presents a wetland network design approach to achieve the objective of water allocation. First, a wetland network was designed by linking linear wetlands (as edges) and patch wetlands (as nodes), the EFRs were then calculated for restoration of wetlands under three scenarios (normal years, dry years, and extremely dry years) defined by annual precipitation; second, the water trade-off between human use and wetland network was determined, and after that water allocation was arranged within the designed wetland network based on certain priorities. Finally, the satisfaction proportion of EFRs, flood-control capacity, and connectivity for the designed wetland network were assessed by two functional indicators and one structural indicator. The results showed that the designed network with three new patch wetlands and water trade-off scenarios made additional water available to wetlands. This additional water amount ranges from 56.1 to 79.4millionm 3 in different scenarios. The three assessment indicators reflect the improved performance of the designed wetland network. This article can promote the understanding of wetland network and serve as water management tool that goes beyond conservation of individual wetland. A wetland network was designed by linking the existing and constructed patch wetlands, and the linear ones to store stormwater and alleviate water shortages. The results show that the performance of the designed wetland network was better and more effective than that of the existing network. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.