An RP-MCE-SOP Framework for China's County-Level Three-Space and Three-Line PlanningAn Integration of Rational Planning, Multi-Criteria Evaluation, and Spatial Optimization

Three-space (including agricultural space, urban and rural construction space, and ecological space) and three-line (including urban development boundary, prime farmland control line, basic ecological control line) planning has been regarded as an essential measure for China's city and county level multiple-plan integration. It handles the multiple planning objectives of development management, agricultural land preservation, and ecological resource protection. This article proposes a rational planning with multi-criteria evaluation and spatial optimization (RP-MCE-SOP) framework for China's county-level three-space and three-line planning by following the rational planning (RP) model and taking advantages of multi-criteria evaluation (MCE) and spatial optimization (SOP) techniques. The framework includes five steps of building the SOP model, land suitability evaluation with MCE, optimization problem solving, post-processing of land allocation solutions, and applying post-processed solutions to three-space and three-line planning. The framework was implemented in Dongxihu District of Wuhan City with the Boolean aggregation and analytical hierarchy analysis (AHP) MCE techniques and the patch-based Non-dominated Genetic Algorithm (NSGA-II) SOP algorithm. The case study shows: (1) The framework is feasible and useful for assisting decision making in three-space and three-line planning. (2) The planning solutions protect ecologically sensitive spaces and high-quality agricultural land and plan future construction in the urban peripheral area or transportation convenient areas. (3) The solutions are useful for planning the hard boundaries for ecological resource protection and prime farmland preservation and setting both hard and soft boundaries for urban growth.