荆江分洪区土地利用时空动态变化研究

通过1986、1996 和 2002 年3期 Landsat TM＼ETM 遥感图像,分析得到荆江分洪区 1986～1996年 和 1996～2002 年土地利用变化情况及土地利用转移矩阵。17年来，荆江分洪区土地利用结构和强度发生了重大的变化。主要表现为：城乡居民及建设用地通过吞食大量耕地、林地而得到迅速增加，年均增幅达到9.66％；林地大规模减少，主要向农业用地和建设用地转变；由于研究区域水旱轮作，水田、旱地年际变化很大，主要根据市场行情决定作物种植。水域和滩涂也逐年减少，年均减幅分别为1.85％和3.34％。土地利用变化的主要驱动因素是人口的增长和经济的发展以及政策制度的激励和导向作用。根据荆江分洪区在整个长江防洪工程中的总体地位，根据分洪区应有别于非分洪区的政策和法规，采取国家扶持和引导，制定合理的规划和经济发展政策，调整区内土地利用结构和控制人口增长，实现分洪和经济可持续发展。

LAND USE DYNAMIC ANALYSIS IN THE JINGJIANG FLOOD DIVERSION DISTRICT, YANGTZE RIVER, CHINA

Types of land uses were extracted from remote sensing images obtained in 1986, 1996 and 2002. The land use conversion matrixes in the study area over two time periods, i.e. 1986-1996 and 1996-2002, were obtained and analyzed based on GIS. The spatial-temporal changes of land uses in Jingjiang flood diversion district show that the settlement and built-up areas underwent changes from farmlands and forest lands and increased distinctly by 9.66% per year in the last 17 years. Forestland was reduced obviously in a large scale, and was converted to farm.lands and settlement and built-up areas. In the study area, dry lands and paddy fields were converted from one to the other in different years, which was mainly based on the crop price in different years. Water surface and bottomlands decreased by 1.85% and 3.34% per year. The main driving force of land use changes is the policy shifts due to the demand of social-economic development and population growth. As an important position in the Yangtze River flood protec- tion, Jingjiang flood diversion district should take special polices different from the protected areas, with the regulation of the land-use structure and the control of populations, and sustainable development.