现代地质Issue(2)：252-259,8.
高砷地下水中溶解性有机碳和无机碳稳定同位素特征
Stable Isotope Characteristics of Dissolved Organic Carbon and Inorganic Carbon in High Arsenic Groundwater
摘要
Abstract
With improved technology for stable isotope analysis,stable carbon isotope has extensively been used in the field of geochemical study.Biogeochemical cycle of groundwater arsenic is one of the hot topics in envi-ronmental studies.This paper summarizes research status of stable carbon isotope in groundwater,and intro-duces pretreating methods and measuring technology of organic and inorganic carbon isotope.Representative groundwater samples with high As concentrations were collected from the Hetao basin,Inner Mongolia,and ana-lyzed for redox-sensitive components,stable carbon isotope in dissolved organic carbon (DOC )and dissolved inorganic carbon (DIC).Results indicate that As distribution is patchy with concentrations between 1.24 and 387 μg/L,and that DOC concentration is relatively high and positively correlated with DIC.In comparison with DOC,DIC is enriched in 13C.There is a positive correlation betweenδ13CDIC -δ13CDOC andδ13CDIC.It indicates that groundwater with lowδ13 CDIC and lowδ13 CDIC -δ13 CDOC values has high contribution of DOC to DIC,which suggests that degradation of organic carbon results in depletion of 13 C in DIC of groundwater.In addition,there is a negative correlation between δ13 CDIC -δ13 CDOC and As.In groundwater with low δ13 CDIC and low δ13 CDIC -δ13 CDOC values,high As concentrations are observed.High As groundwater experiences intensive biodegradation of organic carbon,and microbial degradation of organic matters plays a significant role in promoting the enrich-ment of As in groundwater.The increase in bioavailable organic carbon promotes microbial dissimilation,con-sumes dissolved oxygen,and leads to formation of reducing conditions favorable for As enrichment in groundwater.关键词
溶解性有机碳/溶解性无机碳/稳定同位素/地下水/砷Key words
dissolved organic carbon/dissolved inorganic carbon/stable carbon isotope/groundwater/arsenic分类
天文与地球科学引用本文复制引用
周殷竹,郭华明,逯海..高砷地下水中溶解性有机碳和无机碳稳定同位素特征[J].现代地质,2015,(2):252-259,8.基金项目
国家自然科学基金项目（41222020，41172224）；霍英东基金会第十三届高等院校青年教师基金基础性研究课题（131017）；中央高校基本科研项目（2652013028）。 （）
