湖南湘江流域1990～2010年土地利用/覆被变化及影响因素机理分析

Analysis of land use/cover change from 1990 to 2010 and its driving forces mechanism in Xiangjiang River Basin of Hunan

借助3S技术,以湘江流域1990年及2010年的遥感数据以及经济与社会发展数据为主要数据源,从土地利用类型的结构、转变方向及土地利用综合程度等方面分析其土地利用/覆被时空变化的特征及影响因素.结果表明:(1)近20年来,湘江流域土地利用综合程度增强,耕地和建设用地面积增加,林、草地面积减少,水域及未利用地面积有所增加;(2)耕地向外部扩张侵占林地,林地主要转化为耕地及建设用地;草地面积减少主要是转变为森林;水域主要由耕地中的水田转化而来;建设用地的增加主要来自耕地及林地;未利用地面积增加主要由于湖泊沼泽化;(3)水域及未利用地增长受与气候变化有一定的关系,耕地和建设用地增长主要是经济与社会发展引起的.因此,多种因素共同作用影响下致使耕地递减、林地减少趋势缓和、水域增加以及未利用地中的沼泽地面积增加.

With the remote sensing data of 1990 and 2010 as well as social-economic development data about Xiangjiang River Basin,the space-time variation characteristics and influencing factors of land use/cover were analyzed from the following aspects including land use structure,transformation direction and comprehensive degree. The results may be summarized as follows：（1） The land use pattern in Xiangjiang River Basin has been greatly changed in the past 20 years,the comprehensive degree was enhanced,the area of cultivated land and construction land as well as waters and unutilized land increased while the forestland and grassland decreased;（2） The forestland was mainly changed into farmland and construction land.The area of grassland decreased because it was mainly into the forest.Water mainly came from farmland and paddy field; The increase of construction land was mainly the reason of the transformation from cultivated land and woodland,while the area of unutilized land increased mainly due to the swamping of the lake;（3） There was certain relationship with climate change considering the increase of waters and unutilized land.The increased areas of cultivated land and build-up land were mainly caused by the economic and social development. The changes of cultivated land declining,the eased decreasing trend of woodland as well as water and swamp area increasing were due to combined action of multi factors.