Establishment and evaluation of hydrologically correct DEM in Shaanxi Province.

【Objective】The research was conducted to generate a hydrologically correct DEM in Shaanxi and evaluate the DEM's accuracy.【Method】How to deal with original data rapidly and effectively was studied.From the presentations of terrain,river net and crossing validate,the Hc-DEM and DEM were assessed based on TIN(TIN-DEM).【Result】Hc-DEM can present topography well,and correctly present physiognomy,girder and chimb and stream network,the presentation for topography is better than TINDEM.【Conclusion】The DEM which uses ANUDEM to generate can well represent the real topography,while the quality of this DEM is better than TIN-DEM.For generating the DEM,three main parameters of ANUDEM including resolution,iteration number and 2nd roughness are 50,40,and 0.8 respectively.