Consolidating the layout of rural settlements using system dynamics and the multi-agent system

Abstract The Chinese government has emphasized the consolidation of rural settlements because of their extensive use and hollowing-out in the hope that agricultural land losses can be mitigated nationally, the ecological environment can be protected, and improvements can be made to agricultural production and rural livelihoods. Rural settlement consolidation, however, necessitates a complex optimization approach that involves multiple aspects including rural development policies as well as the evaluation and classification of settlement layout, the land-use decision-making behaviors of villagers, and spatial layout optimization models. Current rural settlement consolidation methods lack these respective modules and have therefore led to unsatisfactory results. We therefore coupled a spatial layout evaluation module, system dynamics (SD) models, and the multi-agent system (MAS) to establish the rural settlement consolidation model (RSCM), an approach which can comprehensively consider all these aspects. This model was then applied in Jizhou District, Tianjin, using the three policy scenarios of ecology priority, coordinated ecology and economic development, and economy priority. The results of this analysis show that, in the first place, given an optimized rural settlement layout, the average suitability value and degree of average spatial compactness increased by 3.23% and 96.68% respectively. These outcomes indicate that the model can improve land-use suitability and solve the village hollowing-out issue. Data also show that landscape pattern indices including average plaque density, average patch shape index, and average fractal dimension all decreased by 54.17%, 26.20, and 4.60%, respectively, while average plaque area increased by 117.22%. These outcomes indicate that the use of this model can reduce rural settlement complexity and alleviate the pressure on the landscape matrix. Secondly, results show that the consolidation of rural settlements leads to clear socioeconomic and ecological benefits within the study area as well as improvements in agricultural production and rural livelihoods because of spatial layout adjustments. Third, ecological and economic policy priorities reduce the effectiveness of rural settlement consolidation, hinder economic development, and can even exacerbate the hollowing-out of villages. Rural development policies must therefore strike a balance between environmental protection and economic development.