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Science China Earth Sciences 2007年第8期50卷 1218-1224页

作者： ZHOU AiFeng CHEN FaHu qiang mingrui YANG MeiLin ZHANG JiaWu CAEP Key Laboratory of West China’s Environmental System(Ministry of Education)Lanzhou UniversityLanzhou 730000China

Detailed examination of sedimentary cores retrieved from Sugan Lake in the northern Qaidam Basin of northwest China’s Tibetan Plateau reveal that fine laminated beddings form in the sediments where water depth exceeds 3 m. Seasonal surface sediments trapped at the bottom of the lake suggest that sediments deposited during summer and autumn are mainly light colored monohydrocalcites, while those deposited in winter are dark organic matter, indicating that varve layers form under modern limnological conditions. Continuous varve sediments comprising four types have accumulated in the upper 5.5 m of Core SG03I from the center of the lake. All types exhibit clear seasonality indicative of annual deposition. Varve counts correspondence with 210Pb dates on recent sediments in the upper core suggest the continuous varves of the upper 5.5 m of the core formed in the late Holocene (2670 a BP). The Sugan Lake varve sequence is the first demonstration of annually laminated sediments re-ported in arid western China.

关键词： Sugan Lake varve Tibetan Plateau arid China

History and possible mechanisms of prehistoric human migration to the Tibetan Plateau

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Science China Earth Sciences 2016年第9期59卷 1765-1778页

作者： ZHANG DongJu DONG GuangHui WANG Hui REN XiaoYan HA PiPu'u qiang mingrui CHEN FaHui Key Laboratory of Western China's Environmental Systems Ministry of Education College of Earth Environmental Sciences Lanzhou University Lanzhou 730000 China Gansu Provincial Institute of Cultural Relics and Archaeological Research Lanzhou 730000 China Qinghai Provincial Institute of Cultural Relics and Archaeological Research Xining 810007 China Cultural Relic Conservation Institute Lhasa 850000 China

Prehistoric human history on the Tibetan Plateau is a hotly debated topic. Archaeological research on the plateau during the past few decades has enormously improved our understanding of the topic and makes it possible for us to consider the processes and mechanisms of prehistoric human migration to the region. By reviewing the published archaeological research on the Tibetan Plateau, we propose that the first people on the plateau initially spread into the He-Huang region from the Chinese Loess Plateau, and then moved to the low elevation Northeastern Tibetan Plateau and perhaps subsequently to the entire plateau. This process consisted of four stages.(1) During the climatic amelioration of the Last Deglacial period(15–11.6 ka BP), Upper Paleolithic hunter-gatherers with a developed microlithic technology first spread into the Northeastern Tibetan Plateau.(2) In the early-mid Holocene(11.6–6 ka BP), Epipaleolithic microlithic hunter-gatherers were widely distributed on the northeastern plateau and spread southwards to the interior plateau, possibly with millet agriculture developed in the neighboring low elevation regions.(3) In the mid-late Holocene(6–4 ka BP), Neolithic millet farmers spread into low elevation river valleys in the northeastern and southeastern plateau areas.(4) In the late Holocene(4–2.3 ka BP), Bronze Age barley and wheat farmers further settled on the high elevation regions of the Tibetan Plateau, especially after 3.6 ka BP. Finally, we suggest that all of the reported Paleolithic sites earlier than the LGM on the Tibetan Plateau need further examination.

关键词： Tibetan Plateau Prehistoric archaeology Human migration Driving mechanisms

Climatic changes documented by stable isotopes of sedimentary carbonate in Lake Sugan,northeastern Tibetan Plateau of China,since 2 kaBP

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Chinese Science Bulletin 2005年第17期50卷 1930-1939页

作者： qiang mingrui CHEN Fahu ZHANG Jiawu GAO Shang-yu ZHOU Aifeng China Center of Desert Research at Beijing Normal University and Key Laboratory of Environmental Changes and Natural Disaster Ministry of Education of China Beijing Normal University Beijing 100875 China Center for Arid Environment and Paleoclimate Research (CAEP) Natiunal Laboratory of Western China's Environmental System Ministry of Education of China Lanzhou University Lanzhou 730000 China

Lake Sugan at the northern edge of the Qaidam Basin was selected as the research object. The temporal se-quence of sedimentary cores retrieved from Lake Sugan since 2 kaBP was reconstructed using the 210Pb, AMS 14C and conventional 14C dating methods. Carbon and oxygen iso-topes of carbonate in the fine-grained lake sediments were analysed. Combined with the changes of δ 18O values of sur-face water and air temperature observation data in the study area, it might be thought that the δ 18O value of the carbon-ate indicates effective moisture, and the changes in δ 13C val-ues are related to annual freeze-up duration of the lake and indirectly indicate air temperature changes in winter half year. From the above, the sequence of climatic changes in the region since 2 kaBP was established. The climatic changes experienced five stages: Warm-dry climate during 0-190 AD; cold-dry climate during 190-580 AD; warm-dry cli-mate during 580-1200 AD (MWP); cold-wet climate during 1200-1880 AD (LIA); cold-dry climate during 1880-1950 AD; and climate warming since 1950s. The air temperature changes in winter half year reflected by carbon isotope since 2 kaBP are in good agreement with the historical literature records and other geologic records, which shows that the climate changes recorded by the stable isotopes from Lake Sugan since 2 kaBP are of universal significance.

关键词：气候变化同位素稳定性碳酸盐沉积作用青藏高原

Changes in palaeoproductivity of Genggahai Lake over the past 16 ka in the Gonghe Basin,northeastern Qinghai-Tibetan Plateau

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Chinese Science Bulletin 2012年第20期57卷 2595-2605页

作者： SONG Lei qiang mingrui LANG LiLi LIU XingXing WANG Qin LI MingZhi MOE Key Laboratory of Western China's Environmental Systems Lanzhou UniversityLanzhou 730000China Cold&Arid Regions Environmental&Engineering Research Institute Chinese Academy of SciencesLanzhou 730000China

Sequential samples of a 7.82-m sediment core from Genggahai Lake in the central Gonghe Basin,controlled with 12 accelerator mass spectrometry (AMS) 14 C dates,have been analysed for total organic carbon (TOC) and total nitrogen (TN) contents,carbon isotope of bulk organic matter (δ 13 C org),and carbonate *** macrofossils and stem encrustations,derived mainly from the species of ***,*** and Chara spp.,were identified,and they dominated the aquatic plant community of the *** of plant macrofossils of Chara *** the vascular species reflect the changing productivity of the lake over *** such a shallow lake,the carbonate content is highly related to photosynthesis of aquatic macrophytes and thus indirectly indicates variations in productivity,consistent with a quantitative estimate of *** on these results,the palaeoproductivity history was reconstructed over the past ca.16 *** lake was formed or recharged at 15.3 cal ka BP,as indicated by aeolian sand deposits at the core base.A marked increase in palaeoproductivity occurred from 15.3 to 11.6 cal ka *** 11.6 and 9.2 cal ka BP,a sharply increased water-level,modulated probably by the enhanced Asian summer monsoon,might have exceeded the optimum water depth for macrophyte vegetation,causing a marked decline in coverage of aquatic macrophytes and low *** palaeoproductivity appeared to be high in the early stage of the period from 9.2 to 7.4 cal ka BP,and then decreased at approximately 8.6 cal ka *** palaeoproductivity sustained an overall high level between 7.4 and 2.1 cal ka BP,and decreased gradually since 2.1 cal ka *** results suggest that the variability of Genggahai Lake palaeoproductivity may be associated with fluctuations of the lake level controlled by the strength of the Asian summer monsoon,probably indicating changes in the Asian summer monsoon.

关键词：共和盆地青藏高原东北部水生植物碳酸盐含量碳同位素分析浅水湖泊夏季季风强度控制

Relationship between climatic conditions and the relative abundance of modern C_3 and C_4 plants in three regions around the North Pacific

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Chinese Science Bulletin 2010年第18期55卷 1931-1936页

作者： RAO ZhiGuo ZHU ZhaoYu JIA GuoDong CHEN FaHu BARTON Loukas ZHANG JiaWu qiang mingrui Key Laboratory of Marginal Sea Geology Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Key Laboratory of Western China's Environment Systems (Ministry of Education) Lanzhou University Lanzhou 730000 China Department of Anthropology University of California Davis CA 95616 USA Katmai National Park and Preserve King Salmon AK 99613 USA

Using -24‰ and -14‰ as the endpoints of stable carbon isotopic composition of total organic carbon (δ 13CTOC) of surface soil under pure C3 and C4 vegetation, and surface soil δ 13CTOC data from eastern China, Australia and the Great Plains of North America, we estimate the relative abundance of C3/C4 plants (i.e., the ratio of C3 or C4 biomass to local primary production) in modern vegetation for each region. The relative abundance of modern C3/C4 vegetation from each region is compared to the corresponding climatic parameters (mean annual temperature and precipitation) to explore the relationship between relative C4 abundance and climate. The results indicate that temperature controls the growth of C4 plants. However, even where temperature is high enough for the growth of C4 plants, they will only dominate the landscape when precipitation declines as temperatures increase. Our results are consistent with those of other investigations of the geographic distribution of modern C4 plant species. Therefore, our results provide an important reference for interpretation of past C3/C4 relative abundance records in these three regions.

关键词：相对丰度 C4植物气候条件周围地区北太平洋表层土壤植物生长温度控制

更尕海现代碎屑物质粒度组成空间分异及其输入过程

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第四纪研究 2010年第6期30卷 1199-1208页

作者：宋磊强明瑞兰州大学西部环境教育部重点实验室兰州730000

文章分析了更尕海表层沉积、流域地表沉积、湖泊水体沉积以及岩芯沉积等的粒度组成,并比较了不同沉积类型之间有关的沉积动力联系。更尕海表层沉积具有4种类型的粒度分布模式,其粒度组成由两个端元组分(粗、细颗粒组分)或者二者的混合... 详细信息

文章分析了更尕海表层沉积、流域地表沉积、湖泊水体沉积以及岩芯沉积等的粒度组成,并比较了不同沉积类型之间有关的沉积动力联系。更尕海表层沉积具有4种类型的粒度分布模式,其粒度组成由两个端元组分(粗、细颗粒组分)或者二者的混合构成。湖泊现代沉积物表现出自西北向东南逐渐变细的趋势。粗颗粒组分主要由风力输入,反映了流域风场状况或风沙活动的强度(如尘暴事件);而细颗粒组分输入过程复杂,其环境意义需要进一步理解。更尕海沉积岩芯样品具有类似于湖泊表层沉积的粒度组成特征,然而其粗颗粒组分的变化可能还受控于湖泊水域面积的分异作用。未来的工作拟将在合理评价湖泊水位变化的基础上。

关键词：粒度湖泊沉积风沙活动更尕海共和盆地

Holocene dust storm variations over northern China:transition from a natural forcing to an anthropogenic forcing

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Science Bulletin 2021年第24期66卷 2516-2527,M0004页

作者： Shengqian Chen Jianbao Liu Xin Wang Shuang Zhao Jianhui Chen mingrui qiang Bing Liu Qinghai Xu Dunsheng Xia Fahu Chen Key Laboratory of Western China’s Environmental Systems(Ministry of Education) College of Earth and Environmental ScienceLanzhou UniversityLanzhou 730000China Group of Alpine Paleoecology and Human Adaptation State Key Laboratory of Tibetan Plateau Earth SystemResources and EnvironmentInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing 100101China College of Geography and Tourism Qufu Normal UniversityRizhao 276826China School of Geography South China Normal UniversityGuangzhou 510631China Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China College of Resources and Environment Hebei Normal UniversityShijiazhuang 050024China

Asian dust storms have long been a major environmental concern in China,affecting the lives of about one billion ***,it is unclear whether the mechanisms responsible for Asian dust storms during the Holocene varied on different timescales,and thus it is unclear whether there was a shift from a natural forcing to an anthropogenic forcing of dust *** reconstructed a high-resolution Holocene record of dust storms from the sediments of an undisturbed alpine lake on the Chinese Loess *** found that Asian dust storm activity generally increased during the Holocene,with the largest fluctuations occurring during the past 2000 *** increase in dust storm activity was in contrast to the decrease in East Asian winter monsoon(EAWM)intensity during the Holocene,indicating that the EAWM played a limited role in modulating dust *** contrast,the increase in dust storms corresponded to a decrease in East Asian summer monsoon(EASM)*** demonstrates that EASM precipitation was the dominant control of dust storm activity on a millennial timescale,because decreased EASM precipitation expanded the desert area and thus increased the dust storm *** increasing intensity of human activity in the region since the Bronze Age resulted in an acceleration of dust storm activity against the background of decreased EASM *** human disturbance continued to intensify,beginning at least at~2 cal ka BP,increased dust storms were closely linked to increasing human populations in the dust source regions,and there is a strong temporal coherence between increased dust storms and higher EASM *** was completely different from when natural processes are *** that period,fewer dust storms occurred during periods of a strengthened ***,there was a shift from a natural forcing to an anthropogenic forcing of dust storms on a multi-decadal to centennial timescale,and was a mode in which‘‘human activity overtoo

关键词： Asian dust storms Early anthropogenic hypothesis East Asian summer monsoon Human activity Northern China

共和盆地更尕海湖泊现代水环境与碳酸盐碳氧同位素组成变化

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科学通报 2015年第9期60卷 847-856页

作者：金彦香强明瑞刘英英李渊李昊李丰山兰州大学西部环境教育部重点实验室兰州730000

通过分析更尕海轮藻碳酸盐结壳、软体动物壳体等碳氧同位素的季节变化,结合湖水溶解无机碳（DIC）碳同位素（δ13CDIC）和湖水氧同位素（δ18OLake）,探讨其与现代湖泊水体环境的关系.结果表明,5~8月,轮藻植物生长速率约为5~6 cm/月;期... 详细信息

通过分析更尕海轮藻碳酸盐结壳、软体动物壳体等碳氧同位素的季节变化,结合湖水溶解无机碳（DIC）碳同位素（δ13CDIC）和湖水氧同位素（δ18OLake）,探讨其与现代湖泊水体环境的关系.结果表明,5~8月,轮藻植物生长速率约为5~6 cm/月;期间,沉水植物强烈的光合作用和碳酸盐的析出导致湖水pH升高,同时湖水DIC和Ca2＋含量显著下降.结合流域水体氧同位素、气温和降水量等观测资料,指出更尕海湖泊水位季节变化是区域降水量与蒸发作用平衡的结果;湖水氧同位素组成主要受入湖水氧同位素组成、湖泊内蒸发过程和降水量等的影响.软体动物壳体氧、碳同位素组成可分别代表δ18OLake与δ13CDIC的年际变化.然而,轮藻结壳氧同位素与δ18OLake之间非平衡分馏效应显著,有待于进一步开展工作.

关键词：碳酸盐稳定同位素轮藻结壳软体动物壳体水体环境

晚更新世共和盆地风沙沉积及其对地貌演化的指示意义

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第四纪研究 2024年第6期44卷 1674-1687页

作者：黄冬月强明瑞刘利陈杰何镇浩邓雅云华南师范大学地理科学学院广东广州510631 兰州大学资源环境学院西部环境教育部重点实验室甘肃兰州730000

共和盆地位于青藏高原东北缘,为一断陷盆地。早-中更新世以沉降为主,发育了广泛的河湖相沉积;中更新世末期的共和运动使得盆地抬升。盆地内广泛发育的河湖相沉积和风成沉积地层,记录了共和盆地的演化历史。然而,由于沉积地层年代数据相... 详细信息

共和盆地位于青藏高原东北缘,为一断陷盆地。早-中更新世以沉降为主,发育了广泛的河湖相沉积;中更新世末期的共和运动使得盆地抬升。盆地内广泛发育的河湖相沉积和风成沉积地层,记录了共和盆地的演化历史。然而,由于沉积地层年代数据相对匮乏,目前针对共和盆地晚更新世风沙活动及环境变化的研究尚未深入。此外,共和盆地由沉降转为抬升并导致黄河下切等地貌演化的关键时限也有待进一步认识。本研究选取共和盆地6个沉积剖面,利用光释光测年以及剖面岩性变化、粒度和元素等古环境代用指标,重建了共和盆地晚更新世风沙活动历史,分析了风沙活动可能的驱动因素。考虑到干旱-半干旱地区河湖环境不但为风沙沉积提供了丰富的物源,而且可能埋藏风沙沉积使其得以保存等事实,依据风成砂沉积时代探讨了晚更新世以来盆地地貌演化过程。结果表明,共和盆地风沙活动主要发生在3个时期,分别为203±12 ka前后、176.2±21.1~143.3±27.8 ka和108±7~86±5 ka。203±12 ka前后,自周围山体的流水携带松散碎屑物由边缘向盆地中心充填,在风力作用下盆地边缘部分地点沉积了风成砂;176.2±21.1~143.3±27.8 ka时期,盆地仍处于充填阶段,盆地内部应以曲流发育为主的河流泛滥平原、浅湖等交错分布,推测河岸与湖泊周边滩地等地貌部位堆积了典型风沙沉积。由此可见,共和运动(或高原面下切)的时限大体应晚于150 ka;108±7~86±5 ka期间,黄河从高原面下切至二塔拉高度(约3000 m a.s.l.),持续至86±5 ka,这一时期大量河湖相物质暴露于地表,为区域风沙沉积提供了丰富的物源,同时形成的层状地貌面也为风沙沉积提供了有利的堆积场所。共和盆地3个时期的风沙活动与盆地水系演化有关,主要受控于风力以及流水作用产生的沙物质供给等的变化,在滨岸或湖泊滩涂等地点堆积风成砂。

关键词：共和盆地风沙沉积共和运动地貌演化

柴达木盆地苏干湖表层沉积与尘暴事件——元素示踪的初步结果

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湖泊科学 2006年第6期18卷 590-596页

作者：强明瑞鲁瑞洁张家武肖舜陈发虎兰州大学西部环境教育部重点实验室中德干旱环境联合研究中心兰州730000 北京师范大学中国沙漠研究中心北京100875

通过分析苏干湖地区10个地表表层沉积物、9个大气降尘(含2个尘暴降尘)、16个湖泊表层沉积物等样品的8种常量-微量元素和11种稀土元素的含量,以及同类沉积不同元素含量和不同沉积同一元素含量的相关性,结果表明,在湖泊沉积体系中Al、Fe... 详细信息

通过分析苏干湖地区10个地表表层沉积物、9个大气降尘(含2个尘暴降尘)、16个湖泊表层沉积物等样品的8种常量-微量元素和11种稀土元素的含量,以及同类沉积不同元素含量和不同沉积同一元素含量的相关性,结果表明,在湖泊沉积体系中Al、Fe、Sc含量的变化与强风-尘暴过程有关,指示了湖泊沉积碎屑颗粒风成输入的可能性．元素Fe、Sc含量在3种不同的沉积物中差异不大,与尘暴事件的强度和频次有关．稀土元素结果显示3类沉积具有同源性．苏干湖沉积可以用来重建研究区尘暴演化历史．

关键词：尘暴事件降尘元素示踪苏干湖