Evaluation Of Land Resource Security In Changwu County

Land resource is the carrier of the national economy development, and land security is concerned with food security, social security, and ecological security. Study on regional land resources security is not only benefitial to the implementation of national land conservation polocies, but also to provide useful reference for regional eco-friendly land use patterns. In this thesis, on the basis of entensive access to domestic and foreign literature on land resource security, the land resource security issues in Changwu County are analyzed. The data is derived from Statistical Yearbook of Changwu County, soil experiment and land use change investigation maps. With the help of the methodologies and theories of land quality evaluation, pressure index of arable land, value of land ecological services function and ecological footprint, the current status of land resource utilization, dynamic spatial variation, land ecological security risks are analyzed. Then the land resources security in Changwu County is evaluated from the following aspects: soil quality status, dynamic temporal and spatial variation of regional arable land-population-grain system and calculation of land ecological footprint. It aims at the understanding of the extent of land resource security and the develop trend. The results of this study are listed as below:(1) On the basis of GIS, soil quality is evaluate with the help of the improved Analytic Hierarchy Process combined with the method of fuzzy mathematics theory to determine the index weight and the synthetic index. In addition, regarding soil organic matter as an example, the temporal variability is analyzed. The results show that, the soil quality in the area is in the middle level and seriously affected by terrain and the soil quality in orchard is better than that in arable land. The level of soil organic matter content is increasing year by year.(2) Using minimum arable land per capita, arable land resources pressure index and regression analysis, the status of arable land area, grain production and population quantity are analyzed and predicted. The results show that the arable land area is decreasing continuously and the grain production per capita is rising. The minimum arable land area per capita is decreasing year by year and the overall arable land pressure has decreased. The obvious increase of grain production is the main factor that could ease arable land pressure effectively in the county.(3) Based on the modification of the previous calculation model of the value of land resource ecological service function, the current land utilization status is analyzed. Data is derived from the land use changing and other related social economic data in the year 1996 and 2006. The research shows that: A. the value of the land ecological service function of Changwu district increased 673.1 million Yuan from 1996 to 2006 and the forest land contribution ratio to the increase reached up to 73.61%; B. the land use changed obviously in this area and there is a large gap between the increasing rate of ecosystem service function vale and GDP.(4) Using improved Ecological Footprint Model (IEFM), the ecological sustainability of Changwu County is calculated and analyzed. The results show that: A Ecological footprint per capita of Changwu county is 0.289 hm2, and ecological carrying capacity per capita is 1.27 hm2, thus the ecological surplus per capital is 0.984 hm2; B Ecological optimum population is 7.481×105 with the proportion to actual population is 0.227, Ecological efficiency (EE) per ten thousand yuan is 0.646 hm2; C Arable land and fossil energy land of Changwu county make up 83% of ecological footprint per capita; Forestry and pasturage land make up 16% of ecological footprint per capita; Built-up land,electric power land,water area and other land make up 1.2% of ecological footprint per capita. The results show that, the pressure to natural ecosystems in Changwu County is within the ecological capacity, the ecological system of Changwu County is relatively in sustainable development situation. IEFM can effectively improve the accuracy and reasonableness of ecological sustainability, and it has extensive applicability in sustainable research, evaluation of optimum population and EE.