太湖流域LUCC对水文过程的影响

基于1971年枯水年、1989年丰水年、2000年平水年3类典型代表年的逐日降雨量、逐日蒸发量以及不同时期地表覆盖遥感分类数据,以城市化快速发展地表覆盖变化明显的太湖流域为研究区域,利用太湖流域河网水量模型进行了土地利用/覆被变化的水文响应研究,分析了太湖流域1990 2000年与2000 2006年间的土地利用/覆被变化及其对水位过程的影响.不仅有利于对城市化地区水文特征变化规律深入了解,也为典型城市化地区防洪减灾提供科学可靠的依据.研究表明,太湖流域城镇化进程的加快引起了土地利用/覆被变化的主要表现是水田、水域等面积向城镇面积转化,城镇化进程加快,2000 2006年期间的城镇化速度大于1990 2000年间;下垫面的变化对太湖流域水文过程产生了明显的影响,随着城市化进程地表覆盖的变化,水位有整体升高的趋势,并且增幅加大,与城镇化速率变化趋势相一致,城镇化程度高的地方水位上升更为明显;降雨量也是水位过程的影响因素之一.

The impact of land use/cover change on hydrological processes of Lake Taihu basin

Based on the daily rainfall, daily water surface evaporation of three typically representative years:dry year, wet year and average year, and land coverage data over different periods, this article selected the Lake Taihu basin which has obvious land cover changes and rapid urbanization as a typical area, to reveal the hydrological response of the basin to land use/cover change(LUCC) using the Taihu river system water quantity model, to analyze the LUCC of Lake Taihu basin from 1990 to 2000 and from 2000 to 2006, and its influence on water level process. This study can not only help for deep understanding on the variation of the hydrological characteristics of urbanized areas, but also can provides more scientific and reliable basis for flood control and disaster mitigation of typical urbanized area. Results showed that the acceleration of urbanization process caused the land use/cover change, whose features are conversion of paddy fields, water area to the urban one, and the acceleration of urbanization process. The urbanization rate for the period from 2000 to 2006 is greater than that during the period of 1990-2000. Underlying surface changes had a significant impact on the hydrological processes of Lake Taihu basin. With the land cover change under the urbanization process, water level increased in the overall, and so did the rate, consistent with the urbanization rate. High degree of urbanization, more obvious water level rising. Rainfall is also one of the factors controlling water level in the process.