East-Asian monsoon variability between 15 000 and 2000 cal. yr BP recorded in varved sediments of Lake Sihailongwan (northeastern China, Long Gang volcanic field)
East-Asian monsoon variability between 15 000 and 2000 cal. yr BP recorded in varved sediments of Lake Sihailongwan (northeastern China, Long Gang volcanic field)
复制标题
DOI：
10.1177/0959683606069388
复制
发表时间：
2006-12
期刊：
影响因子：
--
通讯作者：
G. Schettler;Qiang Liu;J. Mingram;M. Stebich;P. Dulski
中科院分区：
文献类型：
--
作者：
G. Schettler;Qiang Liu;J. Mingram;M. Stebich;P. Dulski
根据计算的生物硅（F-bSiO 2）的净积累速率和附加的代用指标（沉积学数据、沉积物地球化学特征和花粉），对四海龙湾湖（SHL）纹状沉积物进行了15000-2000 cal. yr BP的年代际古水文重建。在SHL湖，F-bSiO 2与富营养地下水的流入呈正相关。由于地下水流入主要是由夏季季风降雨的渗流，F-bSiO 2文件的夏季季风强度的变化。夏季季风降水在全新世早期约9800和7800卡尔。这些时期的地下水流入量没有达到晚冰期温暖期的高水平（c。14300 - 12500 cal. yr BP）时，附近的湖泊是不那么密集覆盖着木本植被比全新世。在9500和8000卡尔年BP之间的整体干燥期，粉砂大小的碎片的风成流入量相对较高。一个中全新世沉积间隔与不同的世纪尺度的变化，在夏季季风降雨的文件降雨和silicicocarbons流入，反映了一个更有效的去除矿物气溶胶的降雨量增加在亚洲大陆的整体高粉尘浓度之间的正相关。夏季季风降雨量在6400、4900、3700和2200 cal. yr BP左右达到最小值。值得注意的是，风成硅质岩流入高峰期的开始和结束之间的干燥间隔4100和3600卡尔。大约3600 cal. yr BP湖SHL收到大量的风成流入不同的地球化学物源。
A palaeohydrological reconstruction on decadal scale for the period 15000-2000 cal. yr BP based on calculated net accumulation rates for biogenic silica (F-bSiO2) and additional proxies (sedimentological data, geochemical sediment characteristics and pollen) is derived from varved sediments of Lake Sihailongwan (SHL). In Lake SHL, F-bSiO2 is positively correlated with the inflow of nutrient-rich groundwater. Since groundwater inflow is mainly fed by seepage of summer monsoon rainfall, F-bSiO2 documents changes in summer monsoon strength. Summer monsoon rainfall was enhanced in the early Holocene around 9800 and 7800 cal. yr BP. Groundwater inflow during these periods did not reach the high level of the Lateglacial warm period (c. 14300 12500 cal. yr BP) when the vicinity of the lake was less densely covered with woody vegetation than in the Holocene. Aeolian influx of silt-sized debris was relatively higher during an overall drier period between 9500 and 8000 cal. yr BP. A mid-Holocene sedimentation interval with distinct century-scale variability in summer monsoon rainfall documents a positive correlation between rainfall and siliciclastic influx that reflects a more efficient removal of mineral aerosols for increased rainfall at an overall high dust concentration over the Asian continent. Summer monsoon rainfall reached minima around 6400, 4900, 3700 and 2200 cal. yr BP. Remarkably, aeolian siliciclastic influx peaked at the beginning and at the end of a dry interval between 4100 and 3600 cal. yr BP. Around 3600 cal. yr BP Lake SHL received substantial aeolian influx of different geochemical provenance.