Mode decision of renovation of rural residential area in post-disaster reconstruction district

Abstract: In recent years, land supply and demand contradiction is increasingly outstanding in China. The land base of rural residential areas is experiencing a reverse development trend of "population decrease but land increase". The main reason is that the rural residential areas have been in a disordered development state with a chaotic layout for a long time. Under the platform of the new round of land renovation planning, rural settlement remediation is being launched all over the country. Estimation of land-renovation potential and determination of the mode of rural residential areas is an important constituent part of land renovation planning. The study area belongs to the "5.12" earthquake disaster area, an earthquake that caused great damage to residents' production and life. According to the phenomenon that the dumped rural residential area could not be reclaimed timely, the thesis divided the renovation potential of the rural residential area of Mianzhu City into two components: intensive farmer reclamation potential and scattered farmer renovation potential; and the renovation potential estimation of the rural residential area was performed by combining the fact-finding data with the average for each household construction land standard method and regarding the administrative village as the unit. On this basis, 15 typical indexes affecting the renovation mode of the reconstruction area were selected in four aspects as follows: physical geography condition, social and economic conditions, infrastructure conditions, and village development direction. The space analysis function of the geographic information system software ArcGIS was utilized to process the present land-use map, the DEM（digital elevation model）to obtain the quantized values of road conditions and elevation of residential areas; and the land-use alteration data were used to calculate the degree of landscape dispersion. Whether the village was regarded as a central village and whether the village had characteristic tourism culture sites were determined by combining the research on the overall plan of new village contraction with the overall plan of the tourism development of the city area. Meanwhile, combining the statistical yearbook data and the renovation potential of the Mianzhu City, six main component factors were extracted from the 15 quantized indexes by utilizing the main component analysis method in SPSS（Statistical Product and Service Solutions）of the multivariate statistical analysis software. The orientations of the main components were determined respectively based on the load of the main components on each variable; then 155 administrative villages were divided into 3-5 types through an agglomerative hierarchical clustering method. Finally, the classification results were compared to obtain 5 kinds of rural residential area renovation modes. The main conclusion is as follows: the renovation potential of the rural residential area of Mianzhu city is 1763.23 hm2; there are 81 villages which are suitable for reformation and improving mode, 15 villages which are suitable for special renovation mode, 16 villages which are suitable for mode of movement and merger of villages, 28 villages which are suitable for gathering and extending mode and 15 villages which are suitable for ecological migration mode. The achievements provide a theoretical support and practice guidance for both the land renovation plan and the decision of the renovation modes of rural residential area in post-disaster reconstruction district.