黑河下游地区柽柳沙丘的气候与环境记录  

Climatic and Environmental Records in the Tamarix ramosissima Nebkha of Heihe River Downstream

作　　者：马健[1,2] 何元庆[1] 冯起[1] 李盼盼[3] 何则[1,2] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所,甘肃兰州730000 [2]中国科学院大学,北京100049 [3]兰州大学西部环境教育部重点实验室,甘肃兰州730000

出　　处：《中国沙漠》2016年第2期319-326,共8页Journal of Desert Research

基　　金：中国科学院知识创新群体项目(KZZD-EW-04-05-01);中国科学院国家外国专家局创新团队国际合作伙伴计划;冰冻圈科学国家重点实验室自主课题(SKLCS-ZZ-2012-01-02);国家自然科学基金创新研究群体项目(41121001;41273010)

摘　　要：对黑河下游地区柽柳沙丘沉积剖面进行AMS 14 C定年及沉积物粒度和Hg含量的综合分析,探讨了该区域从18世纪中期到21世纪初的气候与环境变化。结果表明:沙丘沉积物以细沙为主,粒度频率分布曲线呈明显的单峰形态,反映了单一的风力沉积作用;>100μm的粗颗粒含量变化很好地指示了该区域冬季风的强弱变化,并记录了小冰期末期以来气候转暖的过程以及现代暖期中两个相对寒冷时期——20世纪10—20年代和50—60年代。沙丘沉积物中Hg主要来源于人类的工业活动,剖面Hg含量存在3个峰值,分别对应18世纪末的西班牙美洲地区银矿开采、19世纪中后期的北美淘金热、二次世界大战及战后经济复苏。此外,剖面中有两个样品Hg含量异常升高,其原因可能是1815年和1883年印尼的两次大规模火山喷发而引起的全球Hg沉降增加。We discussed the climatic and environmental changes from the mid-18 th century to the early 21 st century in Heihe River downstream by dating the profile of Tamarix Ramosissima nebkha with AMS14 C and analyzing the grain size and Hg concentration of its sediments.Fine sand is prevalent in nebkha sediments.And the unimodality of the distribution frequency curves suggest that the formation and development of nebkha is dominated by aeolian sedimentation.The content of coarse grains,which indicates the winter monsoon intensity,records the transition from Little Ice Age to modern global warming and two cold periods in the past 100 years：1910s-1920 s and 1950s-1960 s.Then,mercury in nebkha sediments comes mainly from humanity＇s industrial actions.The range of Hg concentration of the profile has three peaks which respectively correspond with the silver mining Spanish America in late 18 th century,the Gold Rush in mid-to-late 19 th century,World War II and the post-war economic resurrection.Besides,Hg concentration are abnormal high in two samples,and it＇s connected with the increase of mercury deposition flux which caused by the volcanic eruption in1815 and 1883.

关 键 词：灌丛沙丘 黑河下游 粒度 HG 气候与环境记录 

分 类 号：P467[天文地球—大气科学及气象学]