Research On Response Of Groundwater Level To Rainfall And Simulation Of Groundwater Flow In Dune-Meadow Area Of Korqin

This article based on the joint observation of natural rainfall and groundwater level data to study the response relationship between groundwater level and rainfall in different type of landform in the dune-meadow region of Horqin. And as a basis for diving infiltration recharge, combining geology drilling, using GMS software to establish a numerical simulation model of groundwater How. The main conclusions were as follows:1. After rainfall in the study area the groundwater level increases in the order:meadow, the dune area of woodland, fixed dunes, semi-fixed dunes, mobile dunes.2. In the dune area, the size of the rainfall is the main factor affecting changes in groundwater levels of rainfall, after the large rainfall event, there will be a period of decline in groundwater level. the duration and increase of groundwater level in the period of decline is positively correlated with rainfall, but if the rainfall intensity reached 40 mm/h in mobile dunes, or 23.8 mm/h in semi-fixed dunes the water table would occur mutation.3. If the previous rainfall events effective rainfall and within a few days short enough. it will promote today-rainfall to recharge groundwater through the influence of dry sand bed thickness and soil moisture, and the effect on changes of groundwater levels before and after rainfall in the dunes is more intense than meadow. when the dune area groundwater depth is less than a critical value, the increasing of groundwater level and water level rise rate becomes larger in the process of rainfall.4. Groundwater level of Meadow area in response to different rainfall intensity is more sensitive than dune area, and meadow area have a greater volatility of groundwater level. In some small level of rainfall, the meadow area of the water table in the fast rise of the water level will rise greater than some of the larger magnitude of rainfall. Plough had a significant effect on the change of groundwater level in the meadow of arid zone.5. Basing on geology drilling and geophysical data to establish three-dimensional geology model and mathematical models of typical dune—weadow alternative area on Horqin sandy dunes. Using groundwater numerical simulation software GMS to establish numerical model of groundwater flow. By repeatedly adjust the model parameters, running and recognition discerning, the model could be used. Lastly, providing a scientific basis to determine hydro-geological parameters of this area, and contributing optimization management, mining of groundwater resources to this area.6. Total recharge of groundwater systems in the study area during the simulation is 321729.5 m3,total excretion is -304092.4m3, balanced difference 17637.2m3. Among them, the rainfall infiltration is the main supply source,76.7% of the total recharge; evaporate is the main excretion item, accounting for 67.9 percent of excretion, livestock and domestic water accounted for 10.8% of total excretion of the groundwater system.