陕北榆林市耕地变化的驱动机制及其情景分析

Driving Forces of Farmland Change and Its Scenario Analysis of Yulin City in Northern Shaanxi Province

选取地处北方农牧交错带的陕北榆林市作为典型研究区,利用历年土地利用详查及其变更数据,并结合野外调研资料,对该区近10年来县域耕地资源变化态势,以及土地退化、退耕还林还草、农业结构调整等因素对耕地变化的影响机理进行了系统研究。主要结论是:(1)榆林市耕地面积总量呈减少趋势,且在不同时段和空间上呈现出显著差异性;(2)土地退化、退耕还林还草、农业结构调整与建设占用是榆林市耕地减少的4个主要原因,其贡献率达98%;(3)草地和未利用地开垦是榆林市耕地面积增加的主要原因,分别占耕地增加总量的48%和39%;(4)未来10年榆林市耕地面积仍以减少为主,但耕地质量会有不同程度的提高。

It has great importance for the regional sustainable development and ecological environment construction to study the macro-driving factors and its scene forecast of farmland change. Taking Yulin for study object which located in the edge of Great Wall of Shaanxi Province, and using detailed data of land use change, combining practical field review, this paper analyze the process of farmland change in the end of 10 years and discussed the influence mechanism of de-farming and reforestation, agricultural structure adjustment to farmland area change. The main conclusion are： （1） The total amount of farmland area has decreased in the near 10 years, and appears great spatio-temporal difference; （2） Land degradation, de-farming and reforestation, agricultural adjustment and building usage are the main reason for farmland decrease, and their contributing rate are 98% ;（3） Reclamation of grassland and no-use land is the main reason of farmland increase in Yulin, it occupy 48% and 39% for total increasing area respectively; （4） The farmland area will decrease still in intending 10 years, but the quality of farmland will be improved in a certain degree.