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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。
The Zr / Rb ratio, which is not affected by late soil-forming processes, can indicate changes in the strength and weakness of wind handling in lake sediments in arid and semi-arid regions, to a certain extent, reflecting the history of regional wind and sand movements. Based on the history of regional climate change and combining with the 45-170 μm particle size fraction of Lake Barkol Lake sediments, , Basin weathering index to discuss. Based on this, the dust activity history of Barkol Lake region in Xinjiang since 9000cal.a BP has been rebuilt: 9000-7300cal.a BP, 5900-3100cal.a BP, 1100-0cal.a BP, high ratio of Zr / Rb in three stages, Frequent activities. 7300-5900cal.a BP, 3100-1100cal.a BP, the Zr / Rb ratio is relatively low and the sand blown activity is weakened, but the peak value of Zr / Rb appears during the period of 2000-1500cal.a BP. According to the research, this may be Erosion due to increased human activities. The results show that the Zr / Rb ratio reflects the association of the sandstorm activity history with the Gurley ice core particle concentration and the Dunde ice core particle content. Therefore, it is considered that the Zr / Rb ratio of lake sediments in arid regions is Reflect the history of the dust activity has a good potential and prospects.