基于RS和GIS的杨凌区土地利用变化及驱动力分析

基于杨凌区1989年土地利用现状图、2004年和2010年拍摄航片目视解译后分别于2007年和2013年的实地核查数据，在ArcGIS 10.0支持下建立3个时期土地利用信息数据库，同时采取多主体访谈调查了233户农户家庭土地利用和经济收入情况等资料，分析了该区域24 a土地利用动态变化特征及其驱动力。结果表明:1989—2013年杨凌区农用地面积减少2 351.36 hm²，建设用地增加2 113.91 hm² ；农用地的减少主要以耕地为主，减少的耕地主要流向建设用地，其次在农用地内部向果园、苗圃和养殖用地转移；耕地内部结构也从粮食作物用地转移至设施栽培用地。杨凌区土地利用变化主要驱动力为政策制度和社会经济因素，国家给予“农科城”特殊区位的优惠和扶持政策，直接引导了土地流转和土地利用结构的宏观变化；经济发展和城镇化进程加快以及受经济利益驱使，也使土地利用由低值向高值转移。农业用地变化总体上处于衰退期，耕地的衰退问题突出，要保持“农科城”的特殊地位，需要科学地协调保护耕地与城乡建设用地需求间的关系。

Analysis of Land Use Changes and Driving Forces in Yangling Based on RS & GIS

Based on the land use status map of Yangling in 1989, and the on-spot inspection data in 2007 and 2013 according to the visual interpretation of aerial photographs of 2004 and 2010, we established land use information database of three periods with ArcGIS 10.0 system, and took multi-agent interviews survey of land use and economic income of 233 farmer households, then analyzed the land use dynamic change characteristics and its driving forces over the past 24 years. The results showed that in the period from 1989 to 2013, agricultural land area decreased by 2 351.36 hm², construction land increased by 2 113.91 hm² in Yangling. The agricultural land reduction was mainly due to the loss of the cultivated land. The cultivated land reduction mainly shifted to the construction land. Next was the land internal transfer in the agricultural system, it transferred to the orchard, the nursery and animal farm land. For the cultivated land, high rate of land changed from cereal crop land to facility-cultivated land. The main driving forces of land use changes were the policy regimes and socio-economic factors. Yangling is an agricultural town, it got some special policies from the central government, which directly guided land transfer and land use structure changes. And economic development and urbanization also accelerated the process, i.e., land use transferred from the low to the high-value products. Agricultural land changes in Yangling were in recession, especially for the cultivated land. To maintain the special status for agricultural town, the scientific coordinated relationships between protecting farmland and meeting the urban-rural construction land demands is necessary.