Distributed Hydrological Model Of Yongding River Mountain Basin And Surface Water Resources Evaluation

In Hai River Basin there are two crucial problems in water resourcesevaluation: large proportion restoration and ferocious change of underlayingsurface. Yongding River mountain basin, a typical region in Hai River Basin,is severely short of water and its exploitured water exceeds eighty percent oftotal. Distinguished in Hai River Basin, underlaying surface of YongdingRiver mountain basin varied sharply due to ground water table descending andresources exploitation. The general method of water resources evaluationbased on data from hydrological fieldwork and restoration. It is very simpleand suitable for basins with little runoff condition change and little humaninterference. However, two problems will occur when it is applied to basinswith large proportion restoration and ferocious change of underlaying surface.One is restoration distortion and the other is restoration invalidation.Restoration distortion means the distortion of hydrological series due to theerror enlargement in restoration analysis. Restoration invalidation means thattraditional method in restoration analysis couldn't explain the phenomenonthat some changes of hydrological underlaying surface resulted in changes ofwater circle rules. Restoration distortion and invalidation raised an austerepoint that how to carry out the water resources evaluation, especially thesurface water resources evaluation under changing conditions. The GBHM(Geomorphology-based hydrological model), one of distributedphysically-based hydrological models, is applied to simulate the hydrologicalprocess, together with the data from hydrological fieldwork and RS. It dependson techniques of GIS and RS to get basin distributed parameters. And itevaluate the natural surface water resources of different underlaying surfacethrough describing the physical runoff process in order to probe into basinrunoff principles caused by changes of underlaying surface. It could avoid the - II -problems of restoration distortion and invalidation. And the results could becompared with those got by general method and make rationality analysis inorder to improve the accuracy of water resources evaluation. On the basis ofresearch on this typical area, the model could be extended to all mountainareas in Hai River Basin and the quantity of natural water resources could bepredicted according to future changes of underlaying surface there. The way that distributed hydrological models are applied to simulatenatural water circle and consequently used in water resources evaluation andrestoration analysis, is first applied in ChaoBai River Basin, another part ofHai River Basin. The results indicated the method is promising. At present themethod is applied to Yongding River mountain basin again in order to verifyits applicability. However, the method is still in the exploration period. So it ishard to avoid some blemishes of theory and technology. Especially in thepractical application, there exist a few problems inevitably, such as theenormous need for various data as well as long computation time.