Transformation Of Surface Water And Groundwater In Plain Area Of Liuhe River Basin,Liaoning Province

Surface water and groundwater are inseparable and important components of water resources.They can closely exchange water quality and quantity,are important factors affecting the formation and structural characteristics of regional water resources,and are the core of terrestrial hydrological cycle research.The research on the interaction between surface water and groundwater is the core and premise of regional water resources evaluation and management.Due to the unclear watershed boundary in the Liuhe Plain and the complex and lack of research on the transformation of surface water and groundwater,the severe water resource utilization situation,in the analysis of the water resources balance of the Liuhe River Basin,it is easy to find that the water resources of the Liuhe River Basin are not adequate balance in the Liuhe River Basin of Liaoning Province.Therefore,a systematic study of surface water-groundwater conversion relationship and conversion law in this area and determination of surface water-groundwater conversion volume can not only recognize the water resources cycle law in the plains area of Liuhe River Basin in Liaoning Province and make better use of water resources,but also provide suggestions and guidance for studying the rivers in the plains area with complex surface water-groundwater conversion relationship.In this paper,series of hydrometeorological data,geological and hydrogeological data,long-term observation data of groundwater,and water consumption data of the study area are collected.From July 2020 to June 2021,field hydrological and hydrogeological surveys will be carried out during the high,flat and dry seasons;On this basis,the relationship between surface water and groundwater transformation in the river reaches is qualitatively analyzed by hydrological measurement.The surface water and groundwater conversion is calculated using the groundwater dynamics method and the flow process segmentation and water balance synthesis method.Establish a numerical model of groundwater in the study area,calculate the conversion between surface water and groundwater,and make predictions for different schemes.The following conclusions were drawn:（1）The joint monitoring results of surface water and groundwater show that:the section of Naodehai Reservoir shows that groundwater replenishes surface water;the section of Fengbao-Yaowopu shows that groundwater replenishes surface water in the west bank,and surface water replenishes groundwater in the east bank;Zhangwu section,Houertaizi-Ciyutuo section and Xinmin section show that surface water recharges groundwater.（2）The relationship between the water level and flow in the upper and lower reaches of Liuhe River and the relationship between surface water and groundwater level show that:the Naodehai-Yaowopu section is the groundwater supply river,and the Yaowopu-Zhangwu section and the Zhangwu-Xinmin section are the river water seepage to supply groundwater.The evolution of the surface water-groundwater relationship in the area below Naodehai of the Liuhe River has regularity,gradually changing from groundwater recharge to river water to river water recharge to groundwater,and the change of the transformation relationship occurs between the Yaowopu-Zhangwu section;the Ciyutuo to Xinmin section may appear The situation of"disconnection"between river water and groundwater still needs further research to verify.（3）The transformation amount of surface water and groundwater is subject to the integrated method of flow process segmentation and water balance.The calculation results show that the Naodehai Reservoir-Yaowopu section is groundwater discharge to recharge surface water,the total amount of groundwater recharge to surface water in the current year is 1.9076 million m~3,and the average total amount of groundwater to recharge surface water from 2000 to 2020 is 1.9553 million m~3;The Naodehai Reservoir-Zhangwu section is mainly composed of surface water that weakly recharges groundwater.The total amount of groundwater recharged by surface water in the current year is 7.3386 million m~3,and the average amount of groundwater recharged by surface water leakage from 2000 to 2020 is 7.3212 million m~3,The Zhangwu-Xinmin section shows that surface water strongly recharges groundwater.The total amount of surface water recharged to groundwater in the current year is26.9977 million m~3,and the average total amount of groundwater discharge to recharge surface water from 2000 to 2020 is 28.7303 million m~3.（4）On the basis of analyzing the hydrogeological conditions of the study area,a numerical model of groundwater in the study area was established,and the conversion between surface water and groundwater in the current year and from 2015 to 2019was calculated and compared with the flow process segmentation and water balance comprehensive method.,the rationality of the integrated method of flow process segmentation and water balance is verified from the perspective of spatial dispersion.On this basis,three prediction models are established to predict the transformation amount of surface water and groundwater and the groundwater flow field.The results show that the groundwater level rises with the increase of precipitation,and the transformation amount increases first with the increase of precipitation,and then the conversion amount was reduced due to the decline of the seepage capacity of the surface water due to the rise of the groundwater level.