The Parameter Uncertainty Analysis And Application Of TOPMODEL And Xin’anjiang Model

The flood disasters occured frequently in Diaojiang watershed, and flood disasters have caused serious loss. In order to alleviate the adverse situation, this paper building schemes of flood forecasting based on TOPMODEL and Xin’anjiang model, ArcGIS and AGREE algorithm are used to repair the DEM and to extract some digital watershed information such as flow direction, slope, rivers, topography index, isochrones, etc. Using Visual studio 2010 to program the TOPMODEL and Xin’anjiang model by C#. TOPMODEL and Xin’anjiang model was applied to provides scientific basis and technical support aimed at making the flood control and decision correctly in Diaojiang watershed.The general likelihood uncertainty estimation method is used to analysis the main parameters sensitivity of TOPMODEL, sensitivity and regional sensitive parameters of Xin’anjiang model. The applicable scope of main parameters of TOPMODEL will be gained by analysis the general flood, larger flood, great flood and extraordinary flood based on deterministic coefficient, the error of the peak flow and peak time.8 floods from 2008-2013 were selected as the floods of calibration period, and 6 floods from 2014-2015 were selected as the floods of validation period, using rainfall and evaporation data to simulate rainfall-runoff process of Diaojiang watershed based on substream.The results of TOPMODEL showed:the percent of pass is 87.5% and the average deterministic coefficient is 0.83 in calibration period, the percent of pass is 83.3% and the average deterministic coefficient is 0.86 in validation period. The results of Xin’anjiang model showed:the percent of pass is 62.5% and the average deterministic coefficient is 0.7 in calibration period, the percent of pass is 66.7% and the average deterministic coefficient is 0.77 in validation period. The simulation results of TOPMODEL have reached the precision level of Serie B in hydro logical forecast.The simulation results of Xin’anjiang model have reached the precision level of Serie C in hydrological forecast. The results show that: TOPMODEL and Xin’anjiang model could provide reference for flood forecasting in Diaojiang watershed.