Optimization of settlement pattern of Honghe Hani terrace based on surface farming radius and MaxENT model

Rural settlements are the main place for human production and life, and their distribution pattern is a reflection of natural, social, economic and historical development. The current rapid urbanization and the decline of traditional agricultural status have made the rural settlements face a crisis of hollowing out or even disappearing. Therefore, the optimization of rural settlement pattern has become a hot issue in global rural research. Optimization of rural settlement pattern is an important work in land consolidation, which is of great significance in alleviating regional conflicts between human and land, solving the problems of “agriculture, rural areas and farmers” and realizing regional sustainability. We took Honghe Hani Terraces World Heritage as the study area, which is located in Yuanyang County of Yunnan province. Firstly, we calculated the distance between settlements and farmland by surface distance method, calculated the overlap degree of farmland by landscape connectivity and buffer method, and then combined the two above with cultivation commuting time to confirm the optimum cultivation radius. Secondly, we identified the planning area of settlement pattern through optimum cultivation radius and the protection regulations of world heritage. Finally, the planning scheme of settlement pattern was proposed based on the potential habitable area that were calculated through eleven physical and human indicators (such as DEM, slope, population) within ecological MAXENT model. The results showed that: 1) The optimum cultivation radius was 1041m. Within its range, the farmland accounted for 75%, the increase of overlap farmland was less than that of farmland, and the cultivation commuting time was less than 20 minutes. 2) Planning area included world heritage area, Xiaoxinjie town and low-density settlements area in the south and north of Yuanyang County. In the world heritage area, population growth of 63.2% from 2005 to 2016 required housing expansion, but it limited strictly by world heritage regulations. In the Xiaoxinjie town, the maximum kernel density of settlements was 1.1 and the overlap farmland area accounted for 7.5% of the county. In the low-density settlements area, the buildings were scattered, the infrastructure was not complete, and the management was unreasonable. Generally, the problems of housing, farmland and management in the planning area need to be specific solved. 3) In the world heritage area that included core area and buffer was 18.42 km2. The settlements in the core area should be entirely preserved according to world heritage regulations and the new populations should be relocated to potential habitable area of heritage buffer or Salatuo. In Xiaoxinjie town, the potential cultivable area was 9.26 km2, which was suitable for settlement and reclamation of farmland. In the low-density settlements area, the potential cultivable area was 92.26 km2. The scattered buildings can be gathered into 2-3 settlements, which were convenient for management and infrastructure construction. The original settlements and farmland could convert into forest and grass. The paper can provide scientific planning suggestions for the reconstruction of farmland and settlements and the protection of world heritage in Yuanyang County.