Layout optimization for rural settlements consolidation based on extended break-point model

Abstract: The objective of the research was to optimize the combination of rural settlement along with land consolidation implementation. The result could be used for decision making associated with planning of land use and rural settlement spatial pattern.Based on central place theory, this study analyzed external and internal influencing factors of comprehensive influence (RSPCI) for rural settlement patch to build evaluation indicator system of comprehensive influence for rural settlement patches. The indicator system weights of RSPCI was evaluated by applying AHP, and the value of RSPCI for each rural settlement patch was calculated by applying unit score weighting. Then, the rural settlement patches and identified optimization strategies were classified according to Jenks natural breaks classification method. Finally, spatial impact range of core at village level based on extended break-point model of weighted Voronoi diagram and the direction of migration of rural settlements were determined in order to optimize the spatial pattern of rural settlements.The results showed that the indicator systems of RSPCI in Zhulin town included four factors: location, residential settlement, natural resources and economics. The weight for each of them was 0.11, 0.31, 0.28 and 0.30 respectively. The rural settlements were divided into four levels based on value of RSPCI including central village, core village, natural village and scattered village levels. The hierarchical structures for different levels of rural settlement were obvious in terms of size and the number. Four kinds of optimization strategies including priority development, restrictive development, combined migration and retention policies should be used to optimize spatial pattern and layout of rural settlement. Among 466 rural settlement patches in the town, 28 were given with full priority to develop, 193 were given with limited priority to develop, 244 were combined and migrated, and 1 was reserved. The migration direction of 244 patches was given by extended break point model of weighted Voronoi diagram. Therefore, rural settlement patches for different levels showed different influences on scope. As a result, different spatial layout optimization strategies should be employed for different rural settlement patches. In order to maintain a stable structure for residential settlement patches, rural settlement patches with low comprehensive influence should be migrated to those with high comprehensive influence during rural settlement consolidation. The results above proposed tools for officers of land management departments in government to make informed decisions for implementing new land use and planning policies.