地质论评2017，Vol.63Issue(1)：235-245,11.DOI:10.16509/j.georeview.2017.01.020
甘青藏地区现代土壤中有机质类异戊二烯烃来源及地质意义
The Distribution Characteristics of Isoprenoids in the Modern Soils in the Gansu—Qinghai—Xizang (Tibet) Area
摘要
Abstract
Objectives:Organic isoprenoids pristine (Pr) and phytane (Ph) formed in the waterbodies under different redox condition,and the ratio of Pr/Ph so can be used to judge the redox characteristics of environments in the past researches.But whether or not they can form in the waterbodies only and how about the stability,there are disregardful.We want to determine Pr and Ph forming or not in the modem soil samples from different ecological environments to study the isoprenoids formation and characteristics,so to show the geological significance of Pr/Ph.Methods:The soluble organic n-alkanes in the modern surface soils from the mid-forests,inter-forests,upper limit forests,lower limit forests,upper limit alpine meadow,and Donggi Cona subalpine desert—meadow in the Gansu,Qinghai and Xizang(Tibet) had been analyzed in this paper.Isoprenoids had been determined based on the m/z85 from the total ion current,and the distribution characteristics and origin of Pr and Ph had been discussed.Results:It is shown that Pr and Ph save in the soils distributing in the different geographical environments not only formed in the waterbodies in the past researched.Pr/Ph ratio is in the range of 0.6 ～ 1.4,mean 0.95;Pr/n-C17 ratio is 0.2 ～ 1.2,mean 0.64;and Ph/ n-C18 is 0.4 ～ 1.4,mean 0.85.There is not a clear relative between Pr/Ph and the soils in the different ecological environments,but there is a mid degree relation between Pr/ Ph with geographical belts.Conclusions:Pr predominance formed by the microorganisms degrade organic matter under aerobic respiration in the relative warm and wet soils.And Ph predominance formed under the anaerobic fermentation in the relative dry and cold soils.Because different parent materials of Pr and Ph,and different sources from terrestrial and waterbodies,and maybe influenced by the forming of Pr and Ph in the process of thermal evolution and diagenesis,Pr/Ph palaeoenvironmental proxy must be testified to judge which kinds of environmental condition in the sediment basins.关键词
甘青藏地区/地表土壤/类异戊二烯烃/微生物/热演化/成岩作用Key words
Gansu—Qinghai—Xizang (Tibet) area/surface soil/isoprenoids/microorganism/thermal evolution/diagenesis引用本文复制引用
张成君,张菀漪,张丽,王小雨,IMBABAZI Berthe,叶生霞..甘青藏地区现代土壤中有机质类异戊二烯烃来源及地质意义[J].地质论评,2017,63(1):235-245,11.基金项目
This study was financially supported by the Nature Science Foundation of China (No.41571177,41601187,41501209) and Basic scientific research fund for Chinese University (lzujbky-2015-254).本文为国家自然科学基金资助项目(编号:NSFC 41571177,41601187,41501209)和中央高校基本科研业务费专项资金(编号:lzujbky-2015-254)的成果. （No.41571177,41601187,41501209）
