新疆巴里坤湖全新世湖泊沉积物中Zr/Rb比值特征及其环境意义  

Variation of Zr / Rb ratios from the Holocene Lacustrine sediments in Balikun Lake in Xinjiang and its environmental implications

作　　者：谭玲玲[1] 钟巍[1,2,3] 薛积彬[1] 魏志强[1] 陈永强[1] 

机构地区：[1]华南师范大学地理科学学院,广州510631 [2]新疆大学绿洲生态教育部重点实验室,乌鲁木齐830046 [3]兰州大学西部环境教育部重点实验室,兰州730000

出　　处：《干旱区资源与环境》2015年第11期109-114,共6页Journal of Arid Land Resources and Environment

基　　金：国家自然科学基金项目(49761007);新疆大学绿洲生态教育部重点实验室基金项目(XJDX0201-2008-02);兰州大学西部环境教育部重点实验室开放基金资助

摘　　要：Zr/Rb比值因不受后期成壤作用影响,在干旱-半干旱地区的湖泊沉积物中可指示风力搬运的强弱变化,在一定程度上反映了区域风沙活动历史。选取西风区巴里坤湖为研究区域,对BLK-1剖面沉积物的Zr、Rb元素及其比值进行分析,并在区域气候变化历史的基础上,结合巴里坤湖沉积物45-170μm粒度组分、流域风化指数展开讨论。据此重建了9000cal.a BP以来新疆巴里坤湖地区的风尘活动历史:9000-7300cal.a BP、5900-3100cal.a BP、1100-0cal.a BP,三个阶段Zr/Rb比值高,风沙活动频繁。7300-5900cal.a BP,3100-1100cal.a BP两个时期,Zr/Rb比值相对低,风沙活动减弱,但在2000-1500cal.a BP期间Zr/Rb比值出现峰值,经研究认为这可能是由于人类活动增强而导致的侵蚀加剧所致。研究表明Zr/Rb比值反映的风沙活动历史与古里雅冰芯微粒浓度、敦德冰芯微粒含量所反映的区域风沙活动具有良好的对应,因此,认为干旱区湖泊沉积物的Zr/Rb比值对于反映区域风尘活动历史具有良好的应用潜力和前景。Zr / Rb ratio from lacustrine sediment can indicate the strength of change of aeolian transport in arid and semi- arid regions,because the post- depostional weathering and pedogenesis does not modify the Zr / Rb ratio due to the immobility of Zr and Rb element. To some extent,Zr / Rb ratio can reflect the history of regional aeolian activity. We selected westerly- influenced Balikun Lake as research region to analyze the Zr and Rb element and Zr / Rb ratio from sediment in BLK- 1 profile. Based on the history of regional climate change,the study combined the（ 45- 170μm） grain- size sensitive component from sediment in Bulikun Lake and catchment weathering intensity（ CWI） to rebuild the history of aeolian activity in Bulikun Lake region of Xinjiang in the past 9000 years. The research suggests： in 9000 ~ 7300 cal. a BP,5900 ~ 3100 cal. a BP,1100 ~ 0 cal. a BP,the fluctuation of Zr / Rb ratio was relatively high and it indicated the big strength of change of aeolian transport and the frequency of aeolian activity during these periods; the aeolian activity weaken during 7300 ~ 5900 cal. a BP and 3100 ~ 1100 cal. a BP; but in the period from 2000 cal. a BP to 1500 cal. a BP,the Zr / Rb ratio increased sharply and reached the climax,showing the strengthened human activity. The research suggests that the history of Aeolian activity that the Zr / Rb ratio reflected was better correspond to that the Guliya ice core and the particle content of the Dunde ice core reflected,so it showed the Zr / Rb ration from lacustrine sediments in arid region has better application potential and prospect to reflect the history of regional aeolian activity from.

关 键 词：Zr/Rb 风尘活动 巴里坤湖 全新世 

分 类 号：P425[天文地球—大气科学及气象学]