嘉陵江流域土地利用/覆被变化特征及其驱动力分析

在GIS技术平台上,通过建立指数模型,对嘉陵江流域1980,1995和2000年3个时期的土地利用/覆被时空变化特征进行了定量研究,并进一步分析了嘉陵江流域土地利用/覆被变化的驱动因素。结果表明:研究区土地利用类型以耕地、林地和草地为主,这3种植被类型之间的相互转化是流域土地利用/覆被变化的主要方式。自1980—2000年,耕地和林地面积先减少后略有增加,草地先增加后减少,建设用地逐年增加,其他地类变化不明显。分析表明,嘉陵江流域土地利用/覆被变化的驱动力主要为自然因素、经济因素、人口因素及宏观政策和工程建设,各因素之间相互影响和制约,共同影响流域土地利用格局的变化。

Characteristics and Driving Forces of Land Use/Cover Change in Jialingjiang River Basin

On the basis of remotely sensed land use data in 1980,1995 and 2000, we quantitatively analyzed the characteristics of the spatio-temporal distribution of land use/cover changes (LUCC) in the Jialingjiang River Basin by using GIS technical platform and establishing index model. Furthermore, we analyzed the driving forces of the LUCC in detail. Results show that farmland, forest and grassland were major land covers in the studied area, and the conversion among the three was the major pattern of land use change. During the period from 1980 to 2000, farmland and forest decreased initially and increased afterwards; grassland increased initially and then decreased; land for construction showed an ever-increasing trend; other land use types were in small change. The analysis showed that natural factor, economy, population, macro-policy and large-scale projects were the main driving forces of LUCC in the studied area. All the factors restricted each other and then affected the land use patterns.