Visual Simulation And Management Of Groundwater In Dunhuang Basin

Combining GIS techniques and Visual ModFlow software, this paper simulates and forecasts the variety,transform and transport of the groundwater in Dunhuang Basin, realizes its two and three dimensional display integrating the space analysis of GIS, cartology and numerical simulation of computer, and advances the management measures of the regional groundwater resource. The result can provide the basis of exploiting the groundwater reasonably and enrich the study, information and visual display of regional hydrology.By analyzing the physical geography, regional hydrology and geology information, and groundwater equilibrium of DunHuang Basin, this paper simulates the aquiferous layer which has the thickness of 250 m, and consider it as two dimension mixed layer which is heterosphere and isotropy. The research region can be divided into 9 subareas, and scattered into 1428 square grids, each length of which is 2 km. In the time, a year is divided into four unequal stress periods in which the initial time scale is 1 day and the increasing factor is 1.3. Comparing with the observation results, the biggest average error of four observation well is 0.14 m in the simulation, the positive and negative error is relatively equal, and the stability of system is better, which means the simulation model accords with the reality of the studying region. Therefore, the simulation model after calibration can meet the demands of evaluation and management.On the basis of development of society, economy and population, the paper forecasts the variation of groundwater of 15 years in the future by the calibrated model, and presents its two and three dimensional forms by using virtual of GIS. The result shows the drop velocity of groundwater table in the Dunhuang city and its south area is larger than that in its north area;the former drop value is about 4-5 m from 2000 year to 2010 year, a funnel of 26 km in diameter will be formed below the Dunhuang city in 2010. The diameter will expand to 30 km to the year 2015, and the drop velocity in the north area is about 10-30 cm per year.In conclusion, in order to ensure the sustainable development of society, ecology and water resource, we should carry out the integrated managements, adjust the water resources use in different industry, strictly control the exploitation of groundwater, implement license system of exploiting groundwater, supervise environmental changes and so on.