| Nowadays, land use/cover change has become the core field of global environmental change research. Land use change research was focused on the quantitative analysis of quantity and structure change of land use in the past. However, at present, changes of land use spatial pattern get widely attention in order to better understand the process and mechanism of land use change and achieve the sustainable use of land resources by adjusting human activities. Land use change model, one of the main research directions of land use/land cover change, has also been paid much attention. CA-Markov model combines the ability of simulating spatial change for complex system of CA model, and the advantage of long-term predication of Markov model, which can improve the predication accuracy of the transformation of land use and effectively stimulate the temporal and spatial change of land use. It has been the widely used to simulate the change of land use spatial pattern.Chongqing, located in the West of China, is a big city with wide countryside, large mountain area, large reservoir and many ethnic minorities. There is a big gap between the urban and rural areas and unbalanced development among different regions. From the establishment of "national urban and rural comprehensive reform pilot area" Chongqing has made exploration and reform on rural household registration, employment, education, health care, endowment insurance, public rental housing, residential land and contracted land. Less attention, however, is paid to land use change of the remote mountainous area after the migration of a large number of surplus rural labor force to the urban area. The Southeast part in Chongqing is a typical poor mountainous area. Recent years, the rapid economic development and the acceleration of urbanization led to the occupation of a large amount of cultivated land and the migration of rural labor force to urban areas, and land use changed significantly, which has become a rare sample for scientific research. Therefore, in this paper, we take Youyang County as the study area and use the land use status data in1996,2005and2011to analyze and simulate the change and developmental trend of the temporal and spatial pattern of land use. The conclusions are as follows: (1) From1996to2011, land use pattern has changed greatly. Generally speaking, construction land, woodland, water land and grassland increase but cultivated land and unused land decrease. Under the influence of policy and natural conditions, unused land°was mainly converted into woodland and grassland. Cultivated land was changed into woodland, grassland and construction land. The key supplements of cultivated land were the exploitation of grassland and the adjustment of construction land. During this period, the landscape was fragmented and the spatial configuration tended to briefness. These changes result from the increasing interference of human activities on land use change of this area.(2) The terrain in Youyang has a major impact on its land use change. Calculated with terrain slope distribution index, cultivated land and construction land are distributed in slope0to25areas. Under the influence of farmland converted into land for ecological preservation, the distribution index of woodland and grassland tends to increase along with the rising of the terrain slope. Comparing the different levels of buffer zones between transportation lines and administrative center of Youyang County, we find that the two have strong spatial attracting effect on construction land. The nearer the transportation lines are, the larger the cultivated land are and away from the administrative center, the cultivated land tends to increase. Besides, economic policy has a significant and far-reaching impact on the spatial pattern of land use.(3) We use CA-Markov model to simulate land use pattern in2020and compare it with the2011data of land use. The finding is that human activities will further accelerate the land use change in Youyang County. Cultivated land continues to decline; woodland, grassland and construction land increase; unused land and water land will not obviously change and the degree of landscape fragmentation deepens. Compared with the plan for overall land use in2020, cultivated land has far exceeded the planning indicator, ecological land has far beyond its planning indicator and the indicator of construction land is adequate, which indicates that ecological environment in the future will be improved gradually but the protection work of cultivated land will face with stern situation in Youyang County. |
PDF Full Text Request