西北干旱区玛纳斯河流域土地宜耕性评价

目的]立足西北干旱区土地开垦与弃耕频繁的土地利用现象,揭示西北干旱区耕地后备资源与不稳定耕地之间的相互联系,以玛纳斯河流域为案例区进行研究,为西北干旱区内陆河流域土地利用与生态保护提供建议。方法]文章运用层次分析法构建评价指标体系,采用综合因子得分法与限制性因子结合法进行土地宜耕性评价,并分别给出空间利用对策。结果]玛纳斯河流域生态敏感性呈“中间大两头小”的数量结构,敏感区面积较大,极敏感及一般敏感区面积都较小;玛纳斯河流域耕地后备资源综合本底条件多为“较好”及“一般”,但开发受生态敏感性影响较大;玛纳斯河流域混合型不稳定耕地及生态型不稳定耕地面积较大,分别为85 684.77hm2、82 011.87hm2,可优先退耕。结论]玛纳斯河流域土地资源丰富,但开发利用受生态约束较大,其宜耕耕地后备资源的合理开发,不稳定耕地的生态退耕,对生态安全及粮食安全具有重要作用。

EVALUATION OF LAND CULTIVATION SUITABILITY IN THE MANAS RIVER BASIN OF THE NORTHWEST ARID ZONE

Based on the land use phenomenon of frequent land reclamations and abandonment by farmers in the Northwest Arid Zone, this study reveals the interconnection between arable land reserve resources and unstable arable land in the Northwest Arid Zone, and uses the Manas River Basin as a case study area, so as to provide suggestions for land use and ecological protection in this inland river basin. This research used a hierarchical analysis to construct an evaluation index system, and with the combination of a comprehensive factor score method and a restrictive factor method, it evaluated arable land suitability and provided spatial utilization countermeasures. The results were listed as follows. The ecological sensitivity of the Manas River Basin had a quantitative structure of "large in the middle and small at the ends", with the sensitive areas being larger and the extremely and generally sensitive areas being smaller, and the comprehensive background conditions of the arable land reserved in the Manas River Basin were mostly "good" and "fair", but development in the area was not easy. The area of mixed unstable and ecologically unstable arable land in the Manas River Basin was sizeable, measuring 85 684.77hm² and 82 011.87hm², respectively, and should not be subjected to any further development or modification, as a priority. Therefore, the Manas River Basin is rich in land resources, but its development and use are subject to greater ecological constraints. The rational development of its arable land reserves and the ecological retirement of its unstable arable land are required to ensure ecological and food security in this region.