Evaluation And Analysis Of Potential Of The Reserved Arable Land Resources In Xinjiang Based On GIS

Arable land is the essence of the land and plays an irreplaceable and fundamental role in agricultural production. With the population increasing and social economy developing, greater and greater demands of various fields have been created for common crops and economic crops. As the great supplement for arable land, arable land reserve resources have become the vitally necessary strategic reserve for safeguarding the national food security.The paper, under such a spectacular background, is intended to specify the theory basis and the evaluating principles through defining the potential of exploiting untouched arable land scientifically; with the aid of geographical information system and remote sensing technology etc., to analyze the theoretical framework of the evaluation comprehensively based on the funder mental multi-source fusion; from the standpoint of suitability, construct the evaluation system of untouched arable land resources in Xinjiang; by conducting five grades land suitability evaluation, to acquire the quantity, quality and the spatial pattern of untouched arable land resources in study area. On that basis, under the constrained condition that the supply and demand in water resource should be balanced, the study improves the spatial distribution of reserve arable land in the unit of river basin. The practical significance of the evaluation and analysis of the potential for arable land reserve resource in study area can be finally represented.Firstly, combining the typical characteristics of the study area,4 suitability indicators (topography, climate, soil and extremely arid factor) and 10 assessment factors (altitude, grade of terrain, accumulated temperature, dryness, soil thickness, soil salinization and etc.) have been chosen to evaluate. By combining analytic hierarchy process with Delphi ensure the proportions of assessment factors. And then using the index sum method to evaluate the land suitability, finally form the comprehensive evaluation indicator system and model based on raster data structure which is 100×100m2, and calculate the suitability class of the land resources in study area for cultivation.Secondly, by extracting and classifying the RS land using data in 2008, the spatial distribution pattern of oasis in Xinjiang can be acquired. The existing cultivated land (10.4 million-mu) are mostly distributed in plain area, among them 96% are plain dry land. At the same time, according to the China 1:1000000 digital topography data, compare the single evaluation indicator models and establish the membership functions of all evaluation indicators for the uniqueness of the landform, finally conduct the analysis of the suitability class of the land resources in study area for cultivation. The evaluation results indicate that the results from the comprehensive evaluation indicator model and the single evaluation indicator model, which are about the land resources for cultivation and the untouched arable land resources, are in good agreement in quantity and overlapped in coverage, this effectively proves the evaluation method and ensures the quality of weighting of different index and the accuracy of suitability grades.Finally, due to the study area belonging to typical temperate continental Arid and Semi-arid Areas, taking the great importance of the water resources to the agriculture into consideration and combining with the Xinjiang Uygur Autonomous Region's strategic decision, which ensures the quantity of land for cultivation according to the water resources, the study regionalizes the river basin. And with the aids of DTW of GIS, applying the geo-statistical method and taking advantages of the spatial analysis model, water resources utilization, the present status of the arable land utilization and the quantity of arable land reserve resources in Xinjiang was analyzed and calculated quantitively and qualitatively based on the data from China Water Resources Announcement and RS land using data in 2008. The water-soil balance index of 30 river basins and the concrete residual quantity for developing can be obtained. In that way the suitability for exploiting untouched arable land resources can be ensured and the appropriate timing for developing can also be arranged scientifically.The evaluation and analysis of potential of the arable land reserve resources for in Xinjiang provides a scientific and theoretical base for adjusting and optimizing the land utilization structure and framing rational land utilization planning. At the same time, it also provides the strategic support for national arable land security and food security timely.