Research Of Spatio-Temporal Expansion Characteristics And Influencing Factors Of Built-Up Areas In Hejin City,Shanxi Province

The current shortage of arable land resources, decreasing arable land per capita,expanding the scale of urban and rural construction land, lots of farmland for construction projects and other phenomenon disappear so frequently, under the rigid constraints of the natural supply of land resources, the supply-demand contradiction is more intensive with the rapid development of urbanization and industrialization,urban sprawl inefficiently and the phenomenon of extensive utilization of urban land is growing. Therefore, improving the efficiency of urban and rural construction,minimizing the supply of land for new construction and vigorously promoting the construction land of economical and intensive use is arable production capacity and achieving food security; protecting construction land and ensuring economic development; protecting ecological environment, ensuring resources. The three strategic objectives are inevitable choice of security of land country.Hejin City in Shanxi Province was selected as the study area, choosing 2005-2012 maps of land use present situation and GIS technology, based on socio-economic statistics, some indexes including built-up area density, expansion intensity index and so on were chosen to analyze the spatio-temporal characteristics,spacial differentiation and morphological changes of urban and rural built-up area in Hejin City in time and space angle.Using the combination of quantitative and qualitative analysis method, the influence factors of affecting the construction land expansion were analyzed.Finally,we made suggestions of promoting construction Land reasonable expansion. Conclusions of this study were as follows:(1) Conclusion of the temporal evolution of urban and rural construction land:The built-up area expansion rate in Hejin City showed decreasing trends, there were obvious stages, the average annual growth rate from2005 to 2009 is1.7%,and the average annual growth rate from2009 to 2012 is 0.62%. Rural residential area accounts for the largest proportion of construction land. The population elasticity index was 3.15 during 2005 to 2009, showing that the urban construction land expanded faster than the demanding of population growth.The population elasticity index was 0.76 in the period of 2009-2012,which was close to fair coefficient. Citi resiliency index was always less than l,and showed a decreasing trend,which meant a high Intensive utilization.(2) Conclusion of the spatial evolution of urban and rural construction land:First,in the study period, the high-density area of urban and rural areas increased year by year,which meant that the built-up area scale developed to cluster scale.The low density area decreased obviously.The increased area and expansion speed of built-up area were evidently greater in rural area than in urban area.Second, the built-up area expanded faster from2005 to2009 than from 2009 to 2012.High speed expansion had mainly concentrated in urban area,and it was developing towards to rural area after 2011. Finally, we analyzed the relationship between the distance from the city center and the construction land expansion intensity,the results showed that the farther the distance from the city center.the weaker the built-up area expanded.(3)Conclusion of the influence factor of the evolution of urban and rural construction land:Policy planning played a very important guiding role,which performed in the role of wind indicator;Pillar industry and the investment in fixed assets forced the expansion of the built-up area primarily.Residents living standards is subsequent power,Traffic built the framework of the expansion of the built-up area in Hejin;Natural geographical environment restricted the construction land expansion.(4) Recommendation of the rational use of urban and rural construction land:Overall planning about urban and rural development configurations,promoting industrial restructuring and deepening reform of the system,these were three aspects of countermeasures and suggestions due to promoting the rational distribution of urban and rural construction land, in order to achieve sustainable socio-economic development.