Dynamic Process Simulation of the Impact of Rain Garden Concentrated Infiltration on Groundwater Level and Quality
In order to explore the impact of concentrated infiltration of rain gardens in plain areas with shallow groundwater burial depth on groundwater level and quality,a campusof a university in Yangzhou was taken as the research area.Based on the measured data of groundwater level and pollutant concentration monitoring data in the research area from July 2018 to June 2019,combined with the actual hydrogeological conditions in the research area,the groundwater numerical model and solute trans-port model were constructed by using Visual MODFLOW software,The changes of groundwater before and after the establishment of rain garden in the study area and the migration process of total phosphorus,nitrate nitrogen and ammonia nitrogen in shallow groundwater after centralized infiltration through rain garden were simulated.The simulation results show that:(1)Under the same rainfall conditions,the recharge and evaporation rates of groundwater before and after theestablishment of rain garden increase by 1.2 m3/day and 1.1 m3/day respectively,indicating that centralized infiltration can increase the recharge of groundwater;(2)During the simulation period,the migration paths of total phosphorus,nitrate nitrogen and ammonia nitrogen in groundwater are consistent with the flow direction,and the migration distances are 11.19 m,71.52 m and 6.7 m respectively,and their concentrations are re-duced to 0.018 mg/L,0.12 mg/L and 0.035 mg/L respectively,and the water quality meets the national health standard,without sig-nificant impact on the groundwater environment,indicating that rain garden can improve the groundwater quality.The research re-sults can provides references for the construction of sponge city and the treatment of groundwater pollution.
rain gardennumerical simulationgroundwaterregional water balancecontaminant transport
万方数据
维普
