| Water is the important natural resources for the mankind survival and development, as well as an important factor for restriction of natural eco-environment. Accompanying the rapid development of economical society, the contradiction between the supply and the requirement of the water resources stands out increasingly, Solving the water resources crisis has been one of the strategic problems in the world. 853 farm lies in Sanjiang plain, it belongs to warmth and half moist agricultural climate area, it is poor in groundwater resources, and it is rich in surface water resources but its utilization degree is not high. Groundwater level changed comparison gentle in this area before 1995, groundwater was basically in the balance of exploitation and supplement of water resources, underground water table has sustained to decline after 1995, especially in recent years the amplitude reduction of underground water level has become more and more large, the groundwater level has the trend of descending if we don't control. So this paper based on the groundwater numerical model and on the basis of balance of water resources supply and demand puts forward two possible plans to control the exploitation of groundwater, and applies the model to predict the trend of groundwater flow field and water level dynamic in each exploitation plan, at last optimizes the second plan as the measure to exploit future groundwater in the 853 farm.This paper mainly is constitute by seven parts, as follows: Introduction, Basic situation of the study area, The method and principle of groundwater flow numerical simulation, Establishment of the groundwater flow mathematical model, Need water prediction and water level prediction of groundwater resources, Management and protection of groundwater resources, Conclusion and deficiency.The key of this paper is the establishment of groundwater flow mathematical model. Analyze hydro-geological condition, establish the hydro-geology conceptual model, through the analysis of physical geography and hydro-geology in 853 farm, this study makes the quatemary confined aquifer as the object of the numerical simulation, and generalizes to be heterogeneity, isotropic and plane two dimensional flow. Use the software of GIS combined with Visual MODFLOW, and use the function of date editing and graphic treatment of GIS, generalize the base map that can be call in Visual MODFLOW. The whole study area is discreted by 800×800mm square grids, 58 rows, 68 columns, and altogether 3944 cells. The simulation stage is from November 5, 2000 to November 4, 2001, each month is one stage, every five days is one step. From November5, 2000 to April 25, 2001 is the stage of model recognition, and from April 26, 2001 to November 4, 2001 is the stage of model validation. Combined hydro-geology, landform and topography with the character of the aquifer, the confined aquifer of the whole study is divided into 4 permeability coefficient areas and 3 coefficient of storage areas. At first, this paper carries on water equilibrium calculation for the study area, then operates the model, identifies parameters of the model through measured and calculated water level fitting, at last validates the model. The groundwater numerical simulation model established by verification is reliable, so it can simulate the present situation and predict the trend of future changes of groundwater resources in 853 farm.This paper combines the present situation and economy situation of society development in 853farm, evaluates the quantity and exploitation present situation of water resources in this area, predicts the change situation of groundwater level from the year 2006 to 2015 with the two plans, analyzes and evaluates the time and space changing rule and the trend of groundwater motion, obtains the optimization scheme on the comparison, suggests to decrease the exploitation quantity of groundwater and fully utilization surface water resources, and does well the scheduling that combines surface water and groundwater.
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