摘要
采用正构烷烃及其单体氢同位素组成特征相结合的方法研究了青藏高原北部多年冻土区表层土壤正构烷烃(C_(21)～C_(33))的生物来源.研究表明:表层土壤中正构烷烃呈双峰型和三峰型的分布特征,表明其具有多个生物来源.长链长正构烷烃(C_(25)～C_(33))主要来源于陆源高等植物.表层土壤中长链长正构烷烃(C_(25)～C_(33))中奇碳数正构烷烃的δD值比偶碳数的整体偏轻,原因可能是两者的生物合成途径不同.对中等链长正构烷烃聚类分析后分为两种类型,类型Ⅰ的中等链长正构烷烃(C_(21)～C_(24))主要来源于陆源高等植物,类型Ⅱ的中等链长正构烷烃主要来源于细菌等微生物降解的产物.表层土壤样品(FHS-10、TG2-10和TG3-10)中等链长的正构烷烃δD值最轻,应为δD值偏轻的水源和细菌等微生物降解共同作用的结果.
Origins of n-alkanes in surface soil from permafrost regions in the northern part of the Tibetan Plateau were studied by the distributions of n-alkanes, and the δD values of individual n-alkanes. That the distributions of the n-alkanes showed bimodal and trimodal patterns, suggesting that they were derived from multiple sources. The long-chain n-alkanes were mainly derived from higher terrestrial plants. Those of odd carbon number(C25~C33) were lighter than those with even carbon number, which might be caused by different biosynthetic pathways. Cluster analysis indicated that the medium-chain typeⅠ n-alkanes(C21~C24) were mainly derived from higher terrestrial plants, and the medium-chain type Ⅱ n-alkanes might have originated from microorganisms such as bacteria. The medium-chain n-alkane δD values of samples FHS-10, TG2-10 and TG3-10 were the lightest, due to both the light δD values of water and bacteria or other microorganisms.
作者
李存林
马素萍
常福宣
何晓波
王利辉
LI Cun-lin;MA Su-ping;CHANG Fu-xuan;HE Xiao-bo;WANG Li-hui(Northwest Institute of Eco-Environment and Resources,Chinese Academy of Science,Lanzhou 730000,China;Key Laboratory of Petroleum Resources Research,Chinese Academy of Sciences,Key Laboratory of Petroleum Resources,Gansu Province,Lanzhou 730000,China;University of Chinese Academy of Sciences,Beijing 100049,China;Water Resources Department,Yangtze River Scientific Research Institute,Wuhan 430010,China;State Key Laboratory of Cryospheric Sciences,Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China)
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2019年第5期2095-2105,共11页
China Environmental Science
基金
国家重点研发计划(2017YFC0405706
2017YFC0405704)
冰冻圈科学国家重点实验室自主课题(SKLCS-ZZ-2018)
中央级公益性科研院所基本科研业务费资助项目(CKSF2017045)
国家自然科学基金资助项目(41271079)
关键词
青藏高原北部
正构烷烃
单体氢同位素
表层土壤
微生物降解
Northern Tibetan Plateau
n-alkanes
δD values of individual n-alkanes
surface soil
microbial degradation
