The Study Of The Impaction Of Regional Shallow Ground Water Dynamic And Chemical Field Evolution By Qiqihar City Industrial Activities

Based on the hydrogeological scientific issues of regional groundwater original and evolution under the impacts of human activities and natural conditions, taken the Qiqihaer City as a typical case in northeastern China, a comprehensive research method of multi subject intersection used in this study, The influence of industrial activities on the dynamic evolution of groundwater dynamic field and chemical field is studied systematically.The thinking mode of analyzing and evaluating the influence degree of the industrial activities on the groundwaterdynamic and chemical field in the urban area was constructed in this study, set the regional groundwater dynamic field and chemical field evolution as the starting point, by inference analysis- proof mentality, clear groundwater dynamic field and chemical field evolution factors gradually, through establishing reasonable quantitative impact assessment system implementation effect of industrial activities on the groundwaterdynamic and chemical field.The concrete achievements are as follows:?1? Systematic review of geological and hydrogeological conditions of the study area and the characteristics of groundwater exploitation and utilization. Environmental isotope technology of ²H,³H,¹⁸O have been applied to prove the precipitation is the same source of local unconfined aquifer and confined aquifer, and the seepage from unconfined aquifer is the main recharge source of confined aquifer, the groundwater recharge, runoff and discharge model has been established. Through the dynamic field of groundwater flow, water level and recharge, runoff and discharge conditions of the spatial-temporal evolution characteristics of each period, the groundwater cone of depression area increased from 0.98 km2 to 8.66 km2 in the past 30 years, the groundwater level decreased 1.53 2.00m; because of the seepage from unconfined aquifer to confined aquifer, the unconfined aquifer cone of depression enlarged, the groundwater level decreased about 2.00 m from 1985 in the central area, the area enlarged about 10 times. Combined with the calculation and analysis of groundwater resources quantity, the precipitation infiltration conditions, aquitard flow effect, groundwater exploitation, groundwater recharge resources and the degree of water level changes are the main factors influencing the regional groundwater dynamic field evolution.?2? Constructed the groundwater chemistry evolution model: spatial-temporal evolution of water chemical type and groundwater chemical composition, from the east plain to the west alluvial valley plains showed ladder like law, chemical concentration increased from east to West, the water chemistry type changed from HCO₃ by HCO₃·Cl, HCO₃·SO₄- type water gradually transition to the SO₄- Cl type water, water quality changed from I III types gradually transition to III V types. Affected by industrial activities, the groundwater quality of unconfined aquifer keep V type in central urban area and southern economic development area, and the underlying confined aquifer has been affected by the seepage, which affected the drinking water safety seriously.?3? The dissolution of rocks and soil mineral compositions, the effect of evaporation concentration and cation exchange adsorption determine the changes of main chemical components in groundwater. The land use type changes for many years are studied in the use of remote sensing images, the increased construction area is directly proportional to the ??NO₃^-?, ?(SO₄^2-), ??Cl?, ??TDS?. Analysis of groundwater pollution component concentration change law in industrial land for many years that ??Zn?, ??Pb? and other heavy metals and ??COD? has rinsed continually. The driving force of chemical model is industrial activity in the center city area, including water-rock interaction.?4? Based on the studies of regional groundwater dynamic field and chemical field characteristics, analytic hierarchy process has been used to establish the evaluation index system of the industrial activities influence on the groundwater dynamic field and chemical field evolution, and establish the evaluation equations for the influence degree, the impact degree assessment of industrial activities on groundwater dynamic field and chemical field have been done with application of GIS technology and mathematical statistical methods.The results show that, the higher influence degree area mainly concentrated in the central city and the Southern Town, groundwater industrial pumping, discharge of industrial waste water and land use are the main factors for groundwater dynamic field and chemical field, and the magnitude of the aggravation of respectively 56 68%,47 56%and 41 56%. The impact area of groundwater dynamic field for unconfined aquifer of industrial activities enlarged about 34.6 km2 from 1999 to 2012, The impact area of groundwater dynamic field for confined aquifer of industrial activities enlarged about 70.1 km2 from 1999 to 2012;The impact area of groundwater chemical field for unconfined aquifer of industrial activities enlarged about 63.4 km2 from 1999 to 2012, however, the chemical field of confined aquifer with less impact from industrial activities. The impact degree of industrial activities on groundwater dynamic field increased from 8.07%to 30.49%, and that of chemical field increased from 13.04%to 31.01%. The industrial activities intensity on chemical field are 0.38,0.31,0.58,0.74 and 0.90, respectively.The industrial groundwater pumping and industrial waste water discharge show strong negative impact on the variation of groundwater dynamic field and chemical field. The effective control of industrial groundwater pumping and industrial waste water discharge should be done to avoid the speed increasing of impact degree of industrial activities on groundwater dynamic field and chemical field.