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以亚洲季风边缘区石羊河流域终端湖猪野泽为例,结合最新的沉积物年代、岩性、指标及古湖泊岸堤研究结果,从时间和空间尺度上探讨了猪野泽中全新世干旱事件时空范围和机制。从空间上对比了猪野泽中全新世地貌及沉积物岩性和指标,并配合石羊河中、上游地区的中全新世沉积剖面进行研究。在时间尺度上分析了猪野泽和石羊河流域近百个全新世测年结果,最终得出猪野泽地区在8.0~7.0 cal ka B.P.期间存在百年尺度的干旱事件,而不是以前研究提出的距今7000~5000日历年期间2000 a尺度的干旱事件,并且这次极端干旱事件影响范围主要在石羊河中、下游地区,对石羊河上游地区影响较小。根据时空尺度分析对猪野泽中全新世干旱事件机制进行讨论,结果表明这次干旱事件主要是由流域气候条件特征和水热配比改变所引起的,而不是以前研究提出的亚洲夏季风减弱导致。
Based on the latest sediment age, lithology and index and the research results of ancient lakes and bank embankments, an example is taken of the end lake, Kitano, in the Shiyang River basin on the Asian monsoon fringe. The Holocene arid event Time and space scope and mechanism. This paper compares the Holocene landscape and sediment lithology and indices in the Yezuo Zeze area with the mid-Holocene sedimentary profiles of the middle and upper reaches of the Shiyang River. Nearly a hundred Holocene dating results of Xunyeze and Shiyanghe basins were analyzed on a time scale. Finally, a century-long drought event at the time of 8.0-7.0 cal ka BP in the Xun’erse area was obtained instead of the previous study This 2000-a-year drought event occurred between 7000 and 5000 calendar years ago, and the impact of this extreme arid event is mainly in the middle and lower reaches of Shiyang River, with less impact on the upper reaches of Shiyang River. Based on the analysis of spatio-temporal scales, the mechanism of the Holocene arid event in the Yezno Zezematsu area is discussed. The results show that this arid event is mainly caused by the change of climatic conditions and hydrothermal ratio in the basin, rather than the decrease of the Asian summer monsoon proposed by previous studies .