| Cultivated land is an important resource for mankind to survive and develop. With economic development and population increase, cultivated land resources has become a very shortage of resources. Songshan District is the national important commodity grain base and demonstration area of pollution-free vegetable production base, which is Sloping land of more than 52.51% of cultivated land. therefore, it has important theoretical value and practical significance to carry out the research on cultivated land evolution rule, evaluation of productivity and evolution simulation in Songshan District in Chifeng City to promote rational allocation of cultivated land resources and optimize production structure of planting industry. This thesis is based on RS and GIS technology, the LUCC theory and landscape ecology theory and applies statistical analysis and mathematical model to conduct the systematic research for cultivated land evolution rule and mechanism of Songshan district 20 years, and build the evaluation system to carry out productivity evaluation for existing cultivated land of Songshan district. Based on the CA- Markov model, this thesis simulates the evolution of arable land of Songshan district in the future, and presents cultivated land utilization pattern. The main results are as follows:1. Based on LUCC, a research on space-time evolution and transfer characteristics of Cultivated Land in Songshan district, and this thesis studies the correlation of cultivated land evolution each the administrative unit by applying the spatial autocorrelation analysis method and analyzes the evolution process from landscape levels and terrain aspects based on ecology theory and orographic factor. The last, this thesis studies the driving mechanism of evolution using the principal component analysis method. The result shows:(1) The result indicates that land use types mainly consist of forestland, grassland and cultivated land in Songshan district, whereas cultivated land space has an obvious distribution. There is obvious difference of spatial structure feature of land use degree between Villages and towns of Songshan district, so the efficiency of land use needs to be improved. Overall development of land is low.(2) The total area of cultivated land in Songshan district has a increasing trend constantly as a whole after going through a process from dramatical increase to increase, but cultivated land of suburb area has a decreasing trend. the spatial difference of cultivated land evolution is obvious, which is divided into the decrease region of cultivated area, the slow increase region of cultivated area and the fast increase region of cultivated area. The change of cultivated area between villages and towns has a significant difference, compared with the whole district. In study period, the main flow direction of the decrease cultivated land is construction land and forestland, the main source of cultivated land increase is grassland and unused land. The change of Global Moran’s index value indicates that cultivated land area changes on agglomerating situation of the spatial distribution in Songshan district increasingly strengthen, and the accumulation situation is transferred from villages and towns of the east to the south central.(3) In landscape level, degree of landscape fragmentation of overall land use is intensifying in Songshan district, landscape types of land use tend to be more complicated and diverse, and the proportion of various patch types area is more and more balanced; the research on changes of cultivated land landscape pattern shows that the scope of cultivated land reclamation is constantly expanding, which leads to the number of cultivated land patches is growing, but the connectivity is reducing, complexity and irregularity of cultivated land patch shape are strengthening, stability of cultivated land spatial pattern is gradually decreasing, and the interference degree of human activities on the cultivated land landscape pattern is bigger.(4) Vertical distribution of cultivated land spatial pattern has significant correlation with elevation, gradient and slope direction, and its characteristics is that with the increase of the height, the relative quantity of cultivated land in the elevation area has a trend firstly increases then decreases; cultivated land conversion has some differences in different terrain area. Low terrain area is the the most active area where cultivated land transfers into construction land. in the region of the high terrain, cultivated land mainly tranfers into grassland and woodland; With the increase of gradient, the number of cultivated land shows a decrease trend, whereas, the selectivity of gradient is higher, so cultivated land is mainly distributed in the half cloudy slope and the half sunny slope, and cultivated land in cloudy slope and the half cloudy slope presents a decrease trend.(5) Social and economic factor and the development of science and technology play a dominant role in the evolution process of cultivated land. This thesis adopts principal component analysis to extract the economic factor and agricultural production efficiency. This thesis adopts multiple linear regression model to reveals the linear relationship between cultivated land quantity and each driving factor, and establishes the driver model.2. Based on GIS technology and fuzzy comprehensive evaluation method, this paper makes a productivity evaluation on existing cultivated land of Songshan district, the result indicates:(1) On the basis of characteristics of cultivated land use in research area, which constructs the evaluation index system of cultivated land productivity and adopts AHP to determine the weight of evaluation factors, at the same time, uses fuzzy comprehensive evaluation method to make the evaluation of cultivated land productivity. Because a variety of organic methods are combined, the evaluation process achieves the basic quantitative. Evaluation results show enough the spatial difference of cultivated land productivity in the study area.(2) Evaluation of cultivated land productivity is divided into five grades, the proportion of high quality cultivated land is lower, and a significant difference was found in the space of cultivated land productivity. Level I of cultivated land is mainly concentrated in the middle-east, level 4 and level 5 are concentrated in the west, the overall level of cultivated land productivity in Songshan area is low3. Based on CA- Markov model, this paper simulates cultivated land evolution of Songshan district, the result shows that land conversion rules being made are feasible, and precision of simulation results of CA- Markov model is higher, which can reflect the general trend of cultivated land evolution in the future. Simulation results show that the cultivated land in the next 10 years is still on the rise, but increase speed is obviously slow, at the same time, the complexity and irregularity of the cultivated land patch shape are still weakening and stability of the spatial pattern of the cultivated land is gradually strengthening.4. This thesis reveals the limiting factor of potential productivity and high efficient utilization of cultivated land, through change and productivity evaluation of cultivated land. This thesis proposes a model of effective utilization of cultivated land in many ways. |
PDF Full Text Request