Selecting reservoir reconstruction schemes from an ecological-economic trade-off perspective: Model building and case study

Abstract

Ecosystem service is the medium of interaction between humans and ecosystems. Reservoirs supply seasonal water to water-scarce areas and have been an important part of the regional ecosystem for their ecological impacts, also providing ecosystem services as an artificial ecosystem. The design and modification of reservoirs can affect the function of the reservoir itself and indirectly change its ecological benefits. In past studies, the selection of reconstruction options only considered the reservoir system, ignoring the long-term interaction within the regional ecosystems and socio-economic systems. To better evaluate the combined effects of schemes, this paper proposes a selection framework based on ecosystem service theory. The ecosystem services value and regional benefits of the reservoir are assessed, the long-term effect is simulated by constructing a dynamic model based on water flow, and the appropriate scheme is certified by the evaluation indicators. The framework is carried out in a case application for Datun reservoir in Shandong Province, China. It is found that: The ecosystem services value of Datun grows from 130.01 to 236.49 M RMB during 2014–2020. The level of ecological benefits is expected to decrease gradually after 2043 because of leakage and evaporation losses. Reconstruction can improve Datun's ability to serve the area, but the ecological and economic trade-offs between the different technology options vary widely. The main contribution of this paper is to weigh the continuous ecological benefits and inputs of different reconstruction schemes from a sustainable, systematic perspective, which is conducive to realizing the healthy operation of reservoirs and promoting regional development.