地质通报2026，Vol.45Issue(2)：421-434,14.DOI:10.12097/gbc.2024.11.057
西藏林周县地下水-地表水化学特征、成因及水质评价
Chemical characteristics,genesis and water quality assessment of groundwater and surface water in Linzhou County,Xizang
摘要
Abstract
[Objective]Linzhou County is the core area of Lhasa River Basin in Xizang.Groundwater and surface water are important drinking water sources and ecological factors in this area.In recent years,the impacts of human activities and climate change on the regional water environment have become increasingly pronounced.This study aims to elucidate the hydrochemical formation mechanisms in Linzhou County,assess current water quality conditions,and provide a scientific basis for water resource protection in plateau regions.[Methods]A total of 37 water samples were collected,and 31 hydrochemical parameters were measured.Comprehensive analytical methods,including mathematical statistics,Piper diagrams,Gibbs diagrams,and ion ratio coefficients,were employed to investigate hydrochemical characteristics and formation mechanisms.Water quality was evaluated using both the Single Indicator Highest Category Method and the Fuzzy Mathematics Method.[Results]The water quality in the study area is characterized as weakly alkaline freshwater,with dominant ions being HCO3-,SO42-,Ca2+and Mg2+ions.The hydrochemical types of water are mainly HCO3-Ca and HCO3•SO4-Ca,demonstrating a strong correlation between groundwater and surface water chemistry.The hydrochemical composition is predominantly governed by rock weathering processes,with silicate and carbonate weathering serving as the principal sources,linked to the geological origins of magmatic,metamorphic,and carbonate rocks in the region.Based on the Fuzzy Mathematics Evaluation Method,water quality classification revealed that 87%of samples met Class Ⅰ standards,5%were Class Ⅱ,and 8%were Class Ⅲ,with no samples falling into Class Ⅳ or Ⅴ.The Single Indicator Highest Category Method identified nitrate,ammonia nitrogen,manganese,and arsenic as the dominant controlling factors.Elevated nitrate and ammonia nitrogen levels were primarily attributed to agricultural activities,while manganese and arsenic exceedances were associated with natural geochemical background conditions.[Conclusions]The overall water quality in Linzhou County remains excellent;however,localized agricultural pollution and geogenic heavy metals require targeted attention.These findings provide a theoretical foundation for water resource management and ecological conservation in high-altitude regions.关键词
水化学特征/形成机制/控制因素/模糊数学法/水质评价/西藏林周县Key words
hydrochemical features/formation mechanism/controlling factors/fuzzy mathematical/water quality evaluation/Linzhou County,Xizang分类
天文与地球科学引用本文复制引用
刘沛,张敏,黄峻川,杨丛鑫,肖飞..西藏林周县地下水-地表水化学特征、成因及水质评价[J].地质通报,2026,45(2):421-434,14.基金项目
中国地质调查局项目《西藏典型地区自然资源综合调查试点》(编号:DD20243093)和《青藏高原湖区湖泊调查》(编号:DD20230509) Supported by the projects of China Geological Survey(Nos.DD20243093,DD20230509) （编号:DD20243093）
