摘要
流域城镇化的水文效应分析对于流域管理十分重要。以长江三角洲地区太湖上游的西苕溪流域为研究区,借助分布式水文模型SWAT对流域降雨径流过程进行模拟分析;在此基础上,结合未来4种城镇化情景,在全流域以及子流域的空间尺度上,年和月的时间尺度上,模拟分析未来城镇化的长期水文效应。结果表明:①在年尺度上,全流域尺度分析表明,未来城镇化情景都将使径流深度增加,蒸发量减小,且随着城镇化比重的增加,二者的变化将更加明显。子流域尺度上,建设用地变化与年径流深度变化之间呈高度线性正相关,径流深度的变化对建设用地面积变化的敏感性高;②在月尺度上,各城镇化情景下大多数月份径流深度增加,且各月蒸发量主要表现出下降的趋势。本文采用水文模型与土地利用变化模型相耦合的方法定量评估未来城镇化对流域水文过程的长期影响,既为土地利用变化水文效应的分析提供了新的理论依据和参考,也为流域管理和规划人员提供了决策基础和方向。
Hydrologic response to urbanization has become a major focus in studies of human’s impacts on hydrology. Hydrologic effects of urbanization play a key role in basin management. The authors combined an empirical land use change model, CLUE-s, with a physically based distributed hydrologic model, Soil and Water Assessment Tool （SWAT）, to examine the potential impacts of future urbanization on hydrology in the Xitiaoxi basin located in the upper reaches of Taihu Lake in the Yangtze River delta （YRD） region. A series of datasets were utilized, including a digital elevation model （DEM） of 50 m resolution, land use maps of the years 1985 and 2002, a pedological soil map of 1985, meteorological observations, and measured streamflows during the period 1988-2004. First, the major parameters of SWAT were identified through sensitive analysis, calibration, and validation. Results show good agreement between the simulated and measured hydrographs at the outlet of the basin, and then the SWAT model suited for the study region was established. Further, 4 future urbanization scenarios for the year 2020 were forecasted using the CLUE-s model based on the land use of 2002. Finally, the 4 scenarios were served as input to the calibrated SWAT model to evaluate the potential impacts of urbanization on basin hydrology. The results are as follows： First, at an annual scale, future urbanization scenarios were projected to increase the total runoff and decrease the evapotranspiration. The higher percentage of the urban area, the more significant impacts will be observed. On the sub-basin scale, changes in the construction land area explicitly show linear positive correlation with changes in annual runoff depth. This suggests that changes in runoff depth are generally sensitive to that of construction land. Second, at a monthly scale, average runoff depth will increase in all months except December, January, February, April, and September, and the increment is especially significant during May to August. As for monthly mean evapotranspiration, the magnitude of the decrease is greatest in late summer and autumn months. This work combines the hydrological model and land use model to quantify the long-term impacts of future urbanization on hydrologic processes of the basin. The results can be helpful for land use planning and watershed management. The modeling approach has been shown to be a promising tool for land use impact studies.
出处
《资源科学》
CSSCI
CSCD
北大核心
2011年第1期64-69,共6页
Resources Science
基金
国家自然科学重点基金项目(编号:40730635)
水利部公益性行业科研专项经费项目(编号:200701024)
国家自然科学基金项目(编号:40571025
J0630535)
高校博士点基金项目(编号:2006084019)
