Suitability Research Of Reserved Arable Land Cultivation In Arid Oasis

Land-utilization pattern directly impacts the ecological stability and social-economy development of oases. Adequate exploit towards suitable land is considered an effective way to balance the quantity and quality of arable land, improving the oasis ecological system, so as to ensure the sustainable development of oases. Economic growth in arid oases has led to growth on population, accompanies with land utilization pressure; blind exploit on land resources has resulted in the decline of arable land quality, ahead with severe impacts towards desertification in the edges of oases and further deterioration of land use structure. In order to ensure the quantity of reserved arable land, and to keep the dynamic equilibrium of arable land, the policy"balance between land consumption and supply"has been put forward and adopted. However, the limit of land resources and the vulnerability of the ecology system in arid area have increased the difficulty of keep the land supplement; determination of reserved arable land with capability of sustainable development has been a key task on land researches at the current stage.This paper focuses on Ugan-Kuqa Rivers delta oasis, a typical arid zone, as the target. Based on"3S"technology, under the support of sufficient fieldwork observation, land utilization data and satellite images, this paper analyses the current land utilization patterns and characteristics; extracts 17 evaluation indicators in natural, ecological and social aspects that are applicable for reserved arable land cultivation suitability; establishes a suitability assessment model based on natural suitability sub-system, taking ecological suitability and social suitability sub-systems as cooperative references, with geo-statistical and mathematical methods such as spatial interpolation, multiple regression analysis, neural network modeling and AHP; assesses and analyses the suitability of reserved arable land cultivation in Ugan-Kuqa Rivers delta; classifies different suitability zones of reserved land cultivation. Conclusions are drawn as follows:(1) Both natural, ecological and social suitability in the study area are moderate, which declines gradually towards east and west from the current oasis zone.(2) Most of assessment units with higher suitability are located within the delta area between Ugan River– Kuqa River - Tarim River. Under the condition of ecological environment safety being ensured, this area is expected to become the main concentration in future reserved arable land cultivation.(3) The total area of reserved arable land assessed"suitable"or"preferred"are 257901.56hm2. Given the condition of sufficient water supply and capital support, the full cultivation is expected to bring over 20000.00hm2 net increase of arable land area. The remaining part of the study area should concentrate on maintenance and enhancement of the current quality of arable land, keeping the stability of the ecological environment.(4) Taking counties concerned, Kuqa county and Xaya county achieves higher scores on both 4 types of suitability, with more distribution of suitable reserved arable land. Suitability index of Kuqa county is slightly over Xaya county. Cultivation of reserved arable land resources in Toksu county should be restrained because of a lower natural suitability index. It is necessary for the counties of Kuqa, Xaya and Toksu to set up strategies of mutual cooperation and harmonious development, attempt to explore a more adequate land utilization pattern and resource allocation, in order to avoid the situation of isolation and repeat construction.(5) Future works of reserved arable land cultivation in the study area should focus on Kuqa county and Xaya county, mainly along the line Hongqi– Hanikatam - Xinken Farm between Kuqa and Xaya. In Toksu, efforts should be focused on enhancing the quality of current arable land, filling the blanks between current agricultural areas, in order to achieve a major breakthrough on both quality and quantity of arable land. It is necessary to pay attention to the prevention of secondary salinization, sand and other ecological threatens. Resources should be reasonably allocated; construction on forest system, irrigation and drainage facilities should be done, to ensure the sustainable development in the study area.