Study On Development Security Of The Reserve Resources Of Cultivated Land In Arid Oasis

The arable land reserve resources are major supplementary source of cultivated land, also affected the sustainable development and stability of oasis'agricultural and ecological environment in arid and semiarid areas. To study the spatial differentiation of arable land reserve resources, and monitor its dynamic changes, which is very important to master the security of the reserve resources of cultivated land, make the arable land reserve resources use policies and measures reasonably, implement sustainable development of oasis'agricultural and so on.This study selected the delta oasis of Weigan and Kuqa River as the typical research area of the reserve resources of cultivated land, which has been researched long-term in Xinjiang's arid area. We used spatial information technology (RS, GIS, GPS), took three period's (1989,2001, and 2007) satellite data as the basic data sources, extracted the distribution of the reserve resources of cultivated land quantitatively and did classification; analyzed the spatial and temporal change of the reserve resources of cultivated land; and built indicator system which contained 21 indicators ,including quantity suitability, quality suitability, ecological suitability and economic suitability, was set up to evaluate the security of development of the reserve resources of cultivated land from 2000 to 2007; implemented the visualization of comprehensive security of development of the arable land reserve resources; put forward control measures of developing the reserve resources of cultivated land.Major conclusions:(1) From aspect of area convertible situation, we found that the reserve resources of cultivated land constantly changed to cultivated land, the cultivated land higher maintain formerly kind, at the same time, large area of forests and fields of weeds were developed to increase the quantity of the cultivated land, besides, little of field of sand, saline alkali land, uncovered land, shoal, water land, wetland and marsh, were exploited to be cultivated land, but there were many problems in the process of development, each kind transferred large area to saline alkali land, vegetation cover ratio was decreased, the development of the reserve resources of cultivated land was not safe.(2) From the space dynamic change, from 1989 to 2007, the changing amount in earlier stage is quicker, the comprehensive speed that the the reserve resources of cultivated land utilizes degree was increased; From the space dynamic change of area, field of weeds and undeveloped land developed towards the direction of increased scale; the annual growth speed of undeveloped land is faster than field of weeds; uncovered land, saline alkali land, shoal, wetland and marsh, soil land developed toward direction of reduce scale; and the reduce speed was quickly in order; at the side of spatial dynamic change degree, spatial dynamic change of undeveloped land is the biggest one, and waste land is the smallest one.(3) From 2000 to 2007, the development of the reserve resources of cultivated land in 2000 was security, which was belonged to more safety condition, and also was 2002. From the overall analysis, the development of the reserve resources of cultivated land was totally decreased, turned to dangerous condition, but after 2001, the security condition of development the reserve resources of cultivated land was slowly improved, after than, the security values were kept nearly 0.4, which was belonged to sensitive condition, the situation of security quickly decreased to dangerous condition in 2006.(4) High security region of the reserve resources of cultivated land in oasis mainly distributed in central agricultural area, and security region, noteworthy region, dangerous region, and highly dangerous region, successively distributed out of central agricultural area; as the area of central agricultural grew larger, the coverage area of most security region became larger, too. Security region almost distributed between oasis and desert interlaces; and expanded from oasis and desert interlaces, all were belonged to dangerous region of the reserve resources of cultivated land, which concluded desert interlaces and ecologically fragile areas in Tarim Basin. From the totally analysis, the area of noteworthy region almost was very large, and dangerous region became larger, but the range of highly dangerous region changed little.(5) Overlay comprehensive security level distribution in 2007 with figure of town, get conclusion as following: see from security level of development, highly dangerous region all distributed in Kuche; dangerous region mainly distributed in Shaya and Kuche, little region of this level distributed in Xinhe ; see from conties, most areas of Kuche were belonged to highly dangerous level and noteworthy level; most areas of Shaya were belonged to dangerous level and noteworthy level; most areas of Xinhe were belonged to noteworthy level and dangerous level.