Assessment Of Groundwater Environment Carrying Capacity In Tongliao Plain

Tongliao plain is located in the middle of West Liaohe plain.As the main source of water supply in the region,groundwater plays an important role in local economy and society development.Tongliao city economic development increases water environmental load,also it increases the risk of damage and pollution of groundwater environment.In order to ensure the coordinated development of groundwater environment and social economy,it is necessary to analyze the relationship between social economy and groundwater environment and then evaluate groundwater environment bearing capacity under the current economic situation.Based on detail research about the study area,this paper establishes the indicator system of groundwater environmental bearing capacity.In order to make full use of existing data to obtain more comprehensive accurate indicator of value,it takes a variety of ways and means to determine the parameter values of each evaluation factor.Based on 3D geological modeling method,we established the 3D geological layer model,the 3D geological structure model and the 3D geological lithofacies model.Then we get the data value of terrain slope index,the thickness of the quaternary system index in the study area and aeration zone lithology index.We establish groundwater numerical simulation model of Tongliao plain from 2003 to 2014,then get the groundwater simulated level in 2014 and the groundwater depth indicator value.By analyzing the groundwater balance result and the evaluation of amount of recharge resources and allowable exploitation quantity,we acquire the values of recharge modulus index and exploitation degree of groundwater resources index.Through consulting related books,policy,and report,we get the data about population,GDP and crop planting area of each county,then we analyze and calculate the corresponding indicators of social economic value.Normalization processing the index values and use analytic hierarchy process(AHP)to determine the index weight.Then evaluate the groundwater environmental bearing capacity of Tongliao plain.According to the bearing capacity of strength the evaluation results is divided into 5 levels.Results show that groundwater environmental bearing capacity in the study area stays the overall level of medium and strong;area respectively is 1.68 x 10~4 km~2 and 1.91 x 10~4 km~2;the area accounted for 39.63%and 39.63%.The area which bearing capacity is weak,weaker and strong is all about 2000 km~2;area ratio is all about 5%.Bearing strong capacity area located in Jarud county,Bannière centrale gauche de Horqin,Naiman county and part of the Bannière arrière gauche de Horqin.Bearing capacity of medium mainly distribution in Kailu county and Naiman county.Keerqin District bearing capacity of the weak.Predicte the groundwater environmental bearing capacity in 2020.Prediction results show that the groundwater environmental bearing capacity won't get worse in the future.The bearing capacity of medium and strong area is increased.Also the bearing capacity of Keerqin District shows the trend of increasingly weak.