以城市化快速发展的太湖流域为研究对象,采用1985、1995和2000年TM/ETM土地利用解译资料,应用区域尺度单元格网分布式水文模型,进行长序列水文模拟,定量评估太湖流域土地利用变化及其水文响应特征,为流域用地规划、水资源管理以及灾害防治提供决策参数。研究显示,自1985年到2000年,太湖流域城镇面积扩展了40.38%,增加量占太湖流域总面积的3.88%。在1980-2000年的雨情下,全流域土地利用变化导致产流量平均增加4.11%,约为7.56×10^8m^3,最高值为11.76%,约为10.0×10^8m^3受土地利用变化空间差异影响,产流量增加具有较大区域差异,城镇快速扩展的苏锡常地区和浦东浦西地区,土地利用变化导致产流量平均增加为10.07%和7.03%,最高增量达20%-30%。
Land use changes alter the hydrological characteristics of the land surface, and have significant impacts on hydrological cycle and water balance. Therefore, it' s very important to study hydrologic response of land use changes for analyzing the complex effects of human activities on natural systems and improving water resource man-agement and flood control. The distributed hydrological model is the key tools that can be used to give insight in the hydrological impacts of land use changes. This paper selects Taihu Basin as study area, with high-speed urbanization. Historical land use scenarios for 1985, 1995, and 2000 were analyzed to track land use change by TM/ETM image explanation and spatial analysis of Arcgis software. The STREAM model, a cell-based distributed hydrological model, was applied to estimate hydrological response of land use changes by simulating the monthly and annual runoff using long-term rain records from 1980 to 2000. For the entire basin between 1985 and 2000, the urban area increased about 40.38% , about 3.88% of the whole basin area. The land use changes result in an increase of 7.56×10^8m^3 on average and 10.0×10^8m^3 on maximum, about 4.11% and 11.76% of the whole basin runoff volume respectively. Hydrological response varies according to the extent of land use changes in different parts of the basin. In Suzhou-Wuxi-Changzhou and Pudong-Puxi sub-region, with more extent of land use changes, the land use changes result in an increase of 10.07% and 7.03% respectively on average, and 20%-30% on maximum.