Research On The Theory And Technology Of Groundwater Reservoir Artificial Regulation Of Taoer River Alluvial Fan In Jilin Province

Water demands increase sharply in recent years with the rapid growth of Chinese GDP.The construction of water reservoir is one of the most effective ways to balance the water demand and supply.When compared to the traditional surface water reservoir,artificial groundwater reservoir is cheap and environment-friendly,which gradually becomes a solution to solve the conflicts between water demand and supply.The alluvial fan of Taoer River located in western Jilin Province,which is an important groundwater reservoir.However,the groundwater level reduces largely due to the over-extraction.This study discuss the possibility to construct a articifical groundwater reservoir based on the shallow aquifers in the Taoer River fan,which stores the abundant rainwater in wet season for water supply in the dry seasons.This paper will review the background of underground reservoirs from four aspects: the concept of underground reservoir,the construction of underground reservoir,the artificial recharge technology of underground reservoir and the regulation of underground reservoir,and to keep abreast of the latest research progress at home and abroad.And then talk about the basic theory of underground reservoirs and the principle of regulation.The spatial conditions,water conditions and ecological conditions of underground reservoirs in Taoer River fan are analyzed in detail,so as to fully demonstrate the feasibility of the study area.Finally,this paper chooses the artificial recharge technology suitable for the study area,and designs the corresponding artificial storage scheme,which provides a theoretical basis for the actual construction of the underground reservoir in the study area,and provides scientific guidance for its management and operation,and has a positive reference value.The following major conclusions are drawn:(1)summary and redefine the concepts of groundwater reservoir as a groundwater engineering that artificially store the excess surface water into the groundwater reservoir,which has a high water-storage space,to balance the water demand and supply.(2)Based on the investigation of the geological and hydrogeological characteristics of the study area,the area of the reservoir area of the proposed underground reservoir is delineated.Through the improved partition stratification method,the spatial subdivision and spatial superposition are used to calculate the feature pool.Considering the uncertainty of specific yield in the calculation process,the Monte Carlo method is used to evaluate the uncertainty of reservoir capacity with Crystal Ball software.The results show that the underground reservoir of Taoer River fan belongs to large(1)underground reservoir.The study area has huge storage space and transfer space,with the strong permeability,excellent internal connectivity,and external sealing,meeting the spatial conditions for the establishment of underground reservoirs.(3)The water budget shows that the maximum recharge could reach 6.07×108m3/a,mainly from the rainwater and river.The use of wavelet analysis,MK test and neural network method to analyze the characteristics of precipitation,indicating that the historical precipitation is fast alternating and there is no obvious decline or a sudden drop.The overall sequence is very smooth;the regression analysis was used to study the leakage of river channels,and the relationship between the effluent and the channel leakage rate was established.The equation shows that there is considerable amount of river leakage in the study area,regardless of the dry season or not.In summary,the amount of the precipitation and the river leakage are sufficient,and the supply is stable,which can meet the requirement of recharge water of underground reservoir.(4)As the traditional water quality evaluation method separating the data screening and data evaluation,the evaluation results are very uncertain.The genetic algorithm,particle swarms algorithm and SVM are combined to assess and predict the water quality of groundwater reservoir in this paper.The model feeds the classification results to update the selection classification factor automatically and use the updated classification factor to optimize the classification results.Finally,it selected ammonia nitrogen,fecal coliform bacteria and other 10 classification factors from the 18 measured factors.The corresponding classification results show that 87% of water samples ranks III-level and above,which satisfy the requirement of the source water for groundwater reservoir.(5)Considering the economic and efficient perspective,this paper selected four kinds of underground reservoir artificial recharge respectively,such as seepage pits,barriers,filter wells and seepage channels.On this basis,with the different mining strength,precipitation conditions and other combinations,this paper designs six storage plans of underground reservoir in Taoer River fan.It shows that artificial recharge is an effective auxiliary mechanism of underground reservoir,with comparison of other scheme.The regulation plan reached a good joint scheduling of surface water and groundwater,while achieving the purpose of multi-year balanced adjustment.The program is in line with the requirements of sustainable development in the study area and is suitable for implementation.