The simplicity of Topography-based hydrological model (TOPMODEL), as a way of reflecting the topographic controls on soil water storage and runoff generation, has become more attractive and more popular for land surfa...The simplicity of Topography-based hydrological model (TOPMODEL), as a way of reflecting the topographic controls on soil water storage and runoff generation, has become more attractive and more popular for land surface process study since digital elevation models (DEMs) have become widely available. In this paper, the effect of the topography index on soil water storage distribution, which is the key to TOPMODEL, is explained. Then a simple water cycle model for estimating other components of the surface water cycle is developed, which is implemented into the TOPMODEL to integrate the water cycle of the catchment. Using the output of a DEM from 100 m×100 m resolution data and a single flow direction algorithm, the index distribution function is calculated for a catchment (around 2500 km2 )in the upper reaches of the Yangtze River under different channel initiation thresholds. Finally, the daily and monthly rainfall-runoff response from 1960 to 1987 for the catchment is simulated with the TOPMODEL coupled with the simple water cycle model.展开更多
The sediment load and river sedimentation of the upper reaches of YangtzeRiver has been undergoing constant changes as complex landform, large mountain area and plentifulprecipitation make the drainage area of Yangtze...The sediment load and river sedimentation of the upper reaches of YangtzeRiver has been undergoing constant changes as complex landform, large mountain area and plentifulprecipitation make the drainage area of Yangtze River very vulnerable to watererosion and gravityerosion. Through analyzing the hydrological and sediment load statistics recorded by majorhydrological stations along Yangtze River since 1950s, and editing the accumulation graph of annualrunoff volume and annual sediment load, wefind out that the suspended-sediment of Yangtze river hasbeen decreasing year by year in Wulong Hydrological Station on Wujiang River, Beibei HydrologicalStation on Jialingjiang River, Lijiawan Hydrological Station on Tuojiang River and GaochangHydrological Station on Minjiang River, Yichang Hydrological Station, Cuntan Hydrological Stationalong Yangtze River mainstream share the same experience too. But the statistics obtained atPingshan Hydrological Station on Jinshajiang River shows the sedimentload there has increased.Taking ecological construction, hydraulic engineering construction and precipitation changes intoconsideration, the thesis analyses the causes for the sediment load decrease of Jialingjiang River,Tuojiang River, Minjiang River and Wujiang River and provides us both scientific foundation forfurther study of river sediment changes of the upper reaches of Yangtze River, and measures tocontrol river sedimentation.展开更多
The contribution of areal precipitation of the catchment from Cuntan toYichang (Three Gorges area) to eight flood peaks of the Upper Yangtze River (the upper reaches ofthe Yangtze River) is diagnosed for 1998 flood se...The contribution of areal precipitation of the catchment from Cuntan toYichang (Three Gorges area) to eight flood peaks of the Upper Yangtze River (the upper reaches ofthe Yangtze River) is diagnosed for 1998 flood season. A rainfall-runoff model is employed tosimulate runoffs of this catchment. Comparison of observed and simulated runoffs shows that therainfall-runoff model has a good capability to simulate the runoff over a large-scale river and theresults describe the eight flood peaks very well. Forecast results are closely associated with thesensitivity of the model to rainfall and the calibration processes. Other reasons leading tosimulation errors are further discussed.展开更多
基金supported by the following projects of China the National Natural Science Foundation of China under Grant Nos.40233034 and 40075019the following projects of China the National Key Program for Developing Basic Sciences G1998040900-Part 1the following projects of China KZCX2-SW-210.
文摘The simplicity of Topography-based hydrological model (TOPMODEL), as a way of reflecting the topographic controls on soil water storage and runoff generation, has become more attractive and more popular for land surface process study since digital elevation models (DEMs) have become widely available. In this paper, the effect of the topography index on soil water storage distribution, which is the key to TOPMODEL, is explained. Then a simple water cycle model for estimating other components of the surface water cycle is developed, which is implemented into the TOPMODEL to integrate the water cycle of the catchment. Using the output of a DEM from 100 m×100 m resolution data and a single flow direction algorithm, the index distribution function is calculated for a catchment (around 2500 km2 )in the upper reaches of the Yangtze River under different channel initiation thresholds. Finally, the daily and monthly rainfall-runoff response from 1960 to 1987 for the catchment is simulated with the TOPMODEL coupled with the simple water cycle model.
文摘The sediment load and river sedimentation of the upper reaches of YangtzeRiver has been undergoing constant changes as complex landform, large mountain area and plentifulprecipitation make the drainage area of Yangtze River very vulnerable to watererosion and gravityerosion. Through analyzing the hydrological and sediment load statistics recorded by majorhydrological stations along Yangtze River since 1950s, and editing the accumulation graph of annualrunoff volume and annual sediment load, wefind out that the suspended-sediment of Yangtze river hasbeen decreasing year by year in Wulong Hydrological Station on Wujiang River, Beibei HydrologicalStation on Jialingjiang River, Lijiawan Hydrological Station on Tuojiang River and GaochangHydrological Station on Minjiang River, Yichang Hydrological Station, Cuntan Hydrological Stationalong Yangtze River mainstream share the same experience too. But the statistics obtained atPingshan Hydrological Station on Jinshajiang River shows the sedimentload there has increased.Taking ecological construction, hydraulic engineering construction and precipitation changes intoconsideration, the thesis analyses the causes for the sediment load decrease of Jialingjiang River,Tuojiang River, Minjiang River and Wujiang River and provides us both scientific foundation forfurther study of river sediment changes of the upper reaches of Yangtze River, and measures tocontrol river sedimentation.
基金Supported by the National Natural Science Foundation of China under Grant Nos. 40175028 and 40475045.
文摘The contribution of areal precipitation of the catchment from Cuntan toYichang (Three Gorges area) to eight flood peaks of the Upper Yangtze River (the upper reaches ofthe Yangtze River) is diagnosed for 1998 flood season. A rainfall-runoff model is employed tosimulate runoffs of this catchment. Comparison of observed and simulated runoffs shows that therainfall-runoff model has a good capability to simulate the runoff over a large-scale river and theresults describe the eight flood peaks very well. Forecast results are closely associated with thesensitivity of the model to rainfall and the calibration processes. Other reasons leading tosimulation errors are further discussed.
