Where and how to restore wetland by utilizing storm water at the regional scale: A case study of Fangshan, China

Wetlands have multiple functions such as biodiversity protection, hydrological regime reduction, pollution sediment filtration, and tourism service etc., though wetland areas have been shrunken and fragmented largely recently, especially where nearby cities. A great application significance can be offered by the application of stormwater resources to wetland landscape restoration, which gives help to deal with the challenge of global precipitation fluctuation, and to build a sustainable and harmonious society between human and nature. In this study, the Priority Index for Wetland Restoration model (PIWR model) and the Stormwater Resources Richness Index model (SRRI model) were established based on 1 km grid unit by taking a typical county scale in northern China as the study area. On this basis, three optimal areas with the PIWR values over 0.43 were evaluated as the targeted areas to receive local stormwater resources, while two areas with the richest stormwater resources of SRRI values over 0.65 were selected as the best water supply areas for the wetland restoration activity. Finally, the optimal and scientific approach was presented based on the proposed accessibility method for utilizing the potential stormwater resources to the planed restore wetland sites at the regional scale. The evaluation framework was supported by proximity analysis and spatial coupling analysis of hydrology and geomorphology based on the suggested multiple ecohydrological indicator matrix. This study presented a useful method framework to help wetland restoration by reducing regional flood disaster with a linkage between an ecological matrix and a hydrological matrix at the regional scale, which can be applied for those regions with a quick loss of wetlands due to the ecological water shortage, while challenged by more and more flooding disasters caused by the coming global climate change.