| Arid areas of northwest China ecological environment is extremely fragile, Minqin oasis as a barrier of the Badain Jaran and the Tengger desert to stop it merger is very important. In recent years, with the continuing impact of human activities in Minqin oasis ecological environment continued to deteriorate, mainly for a large number of land reclamation caused the destruction of natural vegetation which led to the desertification and pay attention Irrigation but ignore Drain led to soil Salinization. land use/cover change (LUCC) is intuitive show of ecological environment change in Minqin oasis. In this study, by20years of LUCC analysis between1991-2010revealed the source of the Minqin oasis ecological environment problem. TM and SPOT Image fusion based on wavelet theory to extract high-precision land-use classification data; Reveals the Minqin oasis spatial and temporal Rules and Features of land use changing by using of remote sensing and GIS technology and a variety of land use dynamic change parameters; Explore the socio-economic factors and reason that caused the land-use spatial and temporal changing by using principal component the analysis and multivariate statistical regression. Predict the future trend of evolution in Minqin oasis land use and spatial pattern by using modeling and simulation techniques. The results of this study provide a theoretical basis for "policy-making that prevent the Minqin become second Lop Nur.The main conclusions of this study as follows:Both arable land, unused land and saline land conversion frequent between1991to2000; The rate of change of arable land the highest in variety of land types, its mainly focus on Dam area before2000but focus on Lakes area after2000. Dynamic degree of land changing focus on Lakes region before2000, but concentrate on Dam area after2000meantime its Continue increasing in lakes region. The year2000, composite index of the land use degree (human activities affect degree) is very obvious in the dam area and relatively weak in Lakes area before2000, in addition to the continues to strengthen in Dam, Lake area increased significantly after2000. Lakes diversity of land-use type is higher than dam area; space center of gravity of land use type was scattered trend, Arable land moving direct to Lake and unused land and residents moving to county direction. The diversity, fragmentation and irregular increased in Minqin oasis in the view of variety of Landscape index, so these changes seriously affect the security of Minqin oasis land use and ecological environment. Overall, Minqin oasis affected by human activities is very significant from the point to the surface gradually extended since1991. Land cover changes in further deterioration of the fragile ecological environment is growing. Use44digitized socio-economic indicators as a candidate driving factors, calculated four principal component driving factors that affect land use change by use of correlation analysis and principal component analysis, these are economic development, technological advances in agriculture, rich or poor condition, the population changed. Quantitative analyze the reason that cause the change in land use by multiple regression model, it Positively associated with Economic development the progress of agricultural technology and population change, and negatively correlated with wealth status. By the calculate of driving factor basis is found that rivers, deserts, roads and urban have certain affect on arable land change, spatial factors is significant reason that caused the land use change.Developed Matlab gray-Markov program based on Mathematical modeling, test results by the actual data analysis showed that the number of simulation error rate was small, fully comply with the requirements of the simulation accuracy. Take advantage of Autologistic autocorrelation driving force analysis, combined with the CLUE-S model to simulate the2010land use and spatial pattern make the1991land use as the initial data. Further analysis revealed that the newly constructed hybrid model simulation results not only improve the simulation accuracy, the location of the simulation results differences was declined, the number of consistent rate was increased, it significantly improved the simulation results.Analyzed three kinds of scenario simulation of land use/cover change result in2030based on the Application of Improved Gray-Markov combination of CLUE-S model.to continue the development of the mode and speed in1991to2010, arable land further increase of6.5×104ha, unused land further reduced;2) the implementation of the policy of Close motor-pumped well and reduce arable land. a certain increase of woodland and grassland, a certain reduction in the trend of salinization, but the settlements continues to grow, without use of change to flatten;3) Reforestation:woodland and grassland will be a significant increase in arable land dropped significantly, the use of land and saline significant trend. Under Scenario1, due to the instability of the arable land, a lot of arable land will result in extremely serious ecological consequences and disaster, be sure to arouse the attention of the government departments. Under Scenario2than the first scenario, the trend toward ecological deterioration containment and improve eco-environmental improvement efforts. Under Scenario3, the trend towards an improvement of ecological environment has clearly improved. |
PDF Full Text Request