吉兰泰沙漠盆地高氟地下水分布规律与形成机理  

Geochemical occurrence, enrichment and distribution of fluoride ingroundwater in the Jilantai Desert Basin

作　　者：吴靓 卢婷[1,3] 郭晋燕[1,3] 卢玉东[1,3] 李环环[3,4] WU Jing;LU Ting;GUO Jinyan;LU Yudong;LI Huanhuan(School of Water and Environment,Chang’an University,Xi’an 710054,China;Qinghai Institute of Geo-Environment Monitoring,Xining 810008,China;Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the Ministry of Education,Chang’an University,Xi’an 710054,China;Department of Hydraulic Engineering,Hebei University of Water Resources and Electric Engineering,Cangzhou 061001,China)

机构地区：[1]长安大学水利与环境学院,西安710054 [2]青海省地质环境监测总站,西宁810008 [3]长安大学旱区地下水文与生态效应教育部重点实验室,西安710054 [4]河北水利电力学院水利工程系,河北沧州061001

出　　处：《灌溉排水学报》2024年第9期113-120,共8页Journal of Irrigation and Drainage

基　　金：青海省科技计划项目(2024-ZJ-767)。

摘　　要：【目的】分析吉兰泰沙漠盆地高氟地下水分布规律,探究绿洲径流区地下水超采对氟解离、迁移和富集的影响机理。【方法】基于SPSS24.0和ArcGIS软件对水化学特征进行数据统计和空间分析;采用Piper三线图、离子比值、Gibbs图解与饱和度指数等方法,结合1980—2020年查哈尔滩绿洲地下水位监测数据和开采数据,探究其高氟地下水水化学特征及成因。【结果】(1)从山地补给区→绿洲径流区→沙漠盐湖排泄区,地下水化学具有分带规律,矿化度、钾离子、钠离子、F-质量浓度逐渐增大,F-质量浓度为0.2~3.4 mg/L;(2)盐湖区地下水F-呈环形岛状分布;沙漠盆地地下水化学的形成主要受含氟岩石的风化作用和蒸发浓缩等自然因素影响;(3)绿洲径流区地下水超采驱动吉兰泰盐湖劣质地下水入侵沙漠绿洲,灌溉回归水的淋滤作用改变了土壤氟解离和迁移模式,导致地下水咸化、高氟化。【结论】综上可知,盐湖排泄区和绿洲径流区地下水氟富集反映了沙漠盆地水文生态环境退化,应采取管灌、滴灌等节水灌溉方式和压缩耕作面积等措施,使查哈尔滩绿洲年地下水开采量减少至700×10^(4)m^(3),以抑制吉兰泰沙漠盆地绿洲灌区的地下水高氟化趋势。【Objective】The purpose of this study is to analyze the distribution pattern of high fluoride groundwater in the Jilantai Desert Basin and explore the impact mechanism of groundwater overexploitation on fluoride dissociation,migration,and enrichment in oasis runoff areas.【Method】The hydrochemical characteristics of groundwater were analyzed by using SPSS 24.0 and ArcGIS software and on the basic of groundwater monitoring data and mining data from 1980 to 2020 in the Chahaertan oasis,the distribution and genesis of high fluoride groundwater were studied by methods such as Piper’s trilinear diagram,ion ratio,Gibbs diagram,and saturation index.【Result】The groundwater chemistry presented zonal distribution,and the concentration of TDS and ions of potassium,sodium ion,fluoride increased from mountain recharge region,oasis runoff area to the desert salt lake discharge region.and the concentration of F-ranged from 0.2 to 3.4 mg/L.In particular,the content of fluoride ion in groundwater around salt lake increased outward.Research result showed that the formation of groundwater hydrochemistry in desert basins was mainly influenced by natural factors such as weathering of fluorinated rocks and evaporation concentration.On the other hand,under excessive extraction of groundwater,poor quality groundwater of salt lakes with high content of fluoride ion invaded into aquifer in desert oases,the irrigation return water leached soil salt,and also affected the migration of fluorine.【Conclusion】The enrichment of fluoride in groundwater reflected degeneration of eco-environment in the Jilantai Desert Basin.Therefore,in order to mitigate these issues and maintain the ecological balance of desert oases,the amount of groundwater exploitation in Chahaertan oasis should be restricted to 7 million cubic meters per year,thereby restraining the worsening trend of groundwater contamination.

关 键 词：高氟地下水 分带规律 地下水开采 咸水入侵 吉兰泰沙漠盆地 

分 类 号：P641.3[天文地球—地质矿产勘探] X143[天文地球—地质学]