SAORES: a spatially explicit assessment and optimization tool for regional ecosystem services

The concept of ecosystem services (ES) has become mainstreamed in environmental planning and management recently, and with that various tools for quantifying ecosystem services have emerged. However, designing the tools for integrated assessment and optimization of multiple ES has become a challenging task. In order to promote the efficiency of ecosystem planning and management, we develop a spatial decision support tool named SAORES, which provides a platform for exploratory scenario analysis and optimal planning design, rather than ES assessment. SAORES is formed with four modules: the scenario development module, the integrated ecosystem service model base, the ecosystem service trade-off analysis module, and the multi-objective spatial optimization module based on NSGA-II. Using SAORES, we make a case study on the Yangou catchment of the Loess Plateau, China. Based on impact assessment of the Grain to green program (GTGP), we optimize the farmland retiring planning, involving multiple objectives which include the eco-compensation and the key ES. The integrated assessment shows that, the aim of the GTGP, the water and soil retention are prominent improved. Optimization for GTGP provides a series of optimal solutions, which are better than other single optimized solutions, and are twice the cost-effectiveness of the actual situation. SAORES, as a decision support tool, can improve the scenario analysis and multi-objective optimal planning design for ecosystem management and planning. The case study demonstrates the potential and effectiveness of SAORES and spatial multi-objective optimization model for ecosystem service management, especially in the Loess Plateau.