中文摘要：

自然资源禀赋差，土地人口承载力低，交通不便，公共服务基础设施差，是贫困山区的基本特征，贫困山区也因此成为人口和产业离心区、生态脆弱区。本文以重庆市酉阳县为例，选取典型村，采用参与式评估、遥感影像和GIS相结合的方法，从微观尺度分析贫困山区农村土地利用演变特征，揭示农村衰落的原因和规律。结果表明：①研究区农村衰落程度严重，植被覆盖率升高，耕地向林草地转变；同时，耕地面积萎缩、聚拢，细碎化程度降低；伴随人口过疏化和老龄化，农村建设用地使用率低，经历由单一到多样，再单一的衰减过程，教育等公共基础服务设施缺位严重；②研究区农村衰落的原因包括农业生计资源匮乏、难以实现农业机械化、聚居分散和城乡比较效益大、农民生活追求的提高以及农业政策实施难度大；③建立以人口流失率、常住人口老龄化率、宅基地萎缩率和耕地变化率4个衰落指标为主的农村衰落诊断方法，诊断表明，研究区农村衰落主要发生在边远山区，距离城镇近、区位优越的农村未表现出衰落。当前农村土地整治和扶贫工作应尊重客观规律，科学制定乡村规划，依靠山区生态系统自我修复、引导人口外迁为主，撂荒耕地择优流转，而复垦未来必然衰落的农村居民I最，肯定造成过程性浪费。

英文摘要：

Few natural resources, a low population capacity, inconvenient traffic and poor public services are characteristics of poor mountainous areas. These areas are centrifugal areas of population and industry that have fragile ecologies. Focusing on seven typical villages in Youyang County in Chongqing City, we analyzed the micro-scale evolution of rural land use to explore rural decline in poor mountainous areas based on participatory rural appraisal methods and remote sensing imagery interpretation. We found that the degree of rural decline in poor mountainous is severe. Along with rural labor flowing into cities and towns and an increasing number of aging people, rural construction land is inefficient, and the diversity of the rural land use changed from simple to richness to simple again. Cultivated land size became smaller, gathered and less fragmented. Meanwhile, the vegetation rate increased due to conversion between cultivated land and woodland. Many reasons, including a lack of agricultural livelihood resources, difficulty in realizing agricultural mechanization, decentralization and the comparative benefits of urban and rural areas were responsible for the decline in rural mountainous areas. A diagnosis index system of rural decline, including population loss rate, rural residential land shrinking rate and reduction in cultivated area was established. This showed that rural decline mainly occurred in remote mountainous villages. We suggest that rural land consolidation and poverty alleviation should obey the object law, making a rural plan scientific. Self-repair of ecosystems should be emphasized in ecological restoration. Cultivated land should be transferred selectively.