Construction Land And The Cultivated Land Quantity Space-time Evolution Pattern And Interactive Mechanism Research

The development of towns depends on the expansion of urban construction land, and the expansion of construction land is bound to take up a lot of land, which is based on arable land. As a big country, China has paid much attention to the grain problem, and the protection of arable land is the important prerequisite for food production. To coordinate the expansion of urban construction land and farmland protection, and to adjust the existing disorderly and inefficient expansion mode of the existing urban construction land is the key problem to be solved. The main city of Chongqing is one of the most developed metropolitan areas in Western China, the population resource is highly concentrated, the construction land is tense, the contradiction is outstanding. Analysis, analytic construction land and farmland in the spatial and temporal patterns of variation of this paper selects the main urban area of Chongqing city as the research object, in 1985-2013 for the study period, from 1985,1996,2000,2007 and 2013, five periods of remote sensing images get basic data, the use of construction land expansion index, the expansion intensity index, expansion coefficient, cultivated land dynamic degree, offset of center of gravity and relative rate of change etc. method of the urban district of Chongqing city construction land, cultivated land. Finally, using the correlation model of construction land and cultivated land of correlation analysis, the construction of interpretation of the interaction mechanism with the change of the cultivated land, and puts forward urban district of Chongqing city construction land expansion and arable land protection coordinated development policy. The conclusions are as follows:1、Construction land expansion speed of the main city of Chongqing has experienced the process of low speed expansion, slow expansion and rapid expansion of the S-change process.;the urban construction land expansion intensity showing to the city center for the origin, characteristics gradually descending to the surrounding area; the construction of Chongqing city land expansion and population growth rationality is low; the construction of Chongqing city in all directions are expansion, and the expansion area, speed has obvious difference, spatial pattern "around," spillover "jump" and "filled" as the main space expansion mode; correlation degree calculation of the social economic factors and the construction land expansion by using the correlation analysis method, the calculated results show that the urban total population, GDP, unit construction land two or three industrial output and total investment in fixed assets and construction there was a significant positive correlation, the density of population and construction land area showed significant negative correlation;2、The area of cultivated land in Chongqing city in the overall downward trend, and in different stages of different decline; urban area land transfer matrix analysis shows that the construction land occupation of cultivated land is the main reason for the decrease of cultivated land area; cultivated land center coordinate changes show that changes 07 years ago is not the center of cultivated land, after 07 years of construction land occupation of cultivated land area increased the center of cultivated land to cultivated land force in eastern region offset more; four stage urban area of cultivated land were -0.37,0.02,-0.72 and -3.47, changes of cultivated land area decreased slowly to sharply reduce the change from urban districts; relative change rate of cultivated land and urban area is consistent, and the internal differences; correlation degree calculation of the society economic factors and land use correlation analysis method, the calculated results show that at the end of the total population, cultivated land and urban population density, urbanization rate, the traditional GDP, the whole society investment in fixed assets, per capita income of farmers was significantly negatively correlated with the proportion of the first industry, there was a significant positive correlation;3、Construction and cultivated land change in correlation analysis showed that the construction land, urban construction land are arable land and was significantly negatively related to construction land, especially the urban construction land is arable land caused a decrease in the main reason; construction land of cultivated land has double effects, cultivated land to construction land play feedback effect.Finally based on the above research suggests fine arrangement of construction land expansion, intensive use of land; construction land try not accounted for or less of arable land, and earnestly protect cultivated land; strengthen land consolidation and reclamation of land, cultivated land dynamic "requisition compensation balance; raise the level of agricultural production, ease of construction land and farmland contradiction etc. countermeasures and suggestions.