The ELSA-Vegetation-Stack: reconstruction of Landscape Evolution Zones (LEZ) from laminated Eifel maar sediments of the last 60,000 years-猫眼课题宝

DOI：

10.1016/j.gloplacha.2016.03.005

发表时间：

2016-04

期刊：

Global and Planetary Change

影响因子：

3.9

通讯作者：

中科院分区：

地球科学1区

文献类型：

作者：

F. Sirocko;H. Knapp;F. Dreher;M. Förster;Johannes Albert;H. Brunck;D. Veres;S. Dietrich;M. Zech;U. Hambach;M. Röhner;S. Rudert;K. Schwibus;C. Adams;Petra Sigl

来自艾菲尔（德国）几个maar湖和干maar湖的层状沉积物记录揭示了过去6万年中欧气候、天气、环境、植被和土地利用的历史。过去3万年的时间序列是基于连续的年代学，MIS3部分是根据格陵兰冰进行调整的——两者都有独立的14世纪年代的年龄控制。利用总碳、花粉和植物大化石合成植被堆，并与季节地层、洪水层、风沙含量和火山层的植被堆一起确定景观演化带（LEZ）。LEZ 1包含了过去6000年受人类广泛影响的景观动态。可追溯到10500 b2k的全新世早期的天然橡树和榛子林定义了lez2。lez3为晚冰期（10,500 ~ 14,700 b2k），湖泊发育了丰富的草木和浅水生物量的北方森林。末次冰期最大值（LEZ 4: 14700 ~ 23000 b2k）以苔藓植被稀疏为特征。这些沉积物通常没有粘土和沙子，也没有显示雪融水事件的迹象。因此，末次盛冰期（LGM）中欧地区一定是极度干旱的。23,000-28,500 b2k的lez5后续沉积物保留了明显的粘土和粗砂层，表明悬浮粘土的流动水和短暂的粗粒河流沉积物排放。丰富的毛茛科大残骸（用于14c测年）、昆虫、苔藓和真菌菌核反映了频繁的强融雪事件期间的苔原环境。总碳含量、桦木-松木花粉和硅藻在海洋同位素阶段（MIS） 3间期（发生在28,500 ~ 36,500 b2k （lez6）之间）均有所增加。整个MIS3间冰期在Auel干泥岩的有机碳记录中得到了很好的记录。而MIS3的主要古植物学指标为草花粉和heliopophytes，表明在间伐期MIS3的古植物学特征为散在/斑块状乔木的草原环境。在lez6期间推断的静止相位揭示了风沙收缩的开始。早期MIS 3森林景观向草原景观的转变发生在LEZ 7-LEZ 6过渡期间。这是现代人在中欧传播的时期。36,500 b2k的主要植被变化为草原，这一定有利于马的传播，马是现代人类重要的狩猎猎物。因此，我们提出，现代人类向中欧的迁移可能至少部分是由气候和相关植被变化驱动的。LEZ 7的时间间隔为36,500至49,000 b2k，其特征是在间隔期活动期间拥有丰富的松树，桦树和云杉的北方森林。大量的木炭碎片表明这片针叶林经常遭受干旱胁迫，经常燃烧。最出乎意料的发现是，在49,000至55,000 b2k （LEZ 8）范围内，嗜热树木类群占主导地位，但所有的maar记录都证实了这一点。根据艾菲尔花粉记录，格陵兰岛的间冰期13和14显然是MIS 3中最热的。之前的LEZ 9在55000 ~ 60000 b2k范围内也以云杉为主，但喜热树木较少。温暖的MIS3早期似乎是合理的，因为mi3早期的夏季日照（60°N）比今天高，斯堪的纳维亚半岛的冰盖较低，北大西洋的海表温度几乎与…

Laminated sediment records from several maar lakes and dry maar lakes of the Eifel (Germany) reveal the history of climate, weather, environment, vegetation, and land use in central Europe during the last 60,000 years. The time series of the last 30,000 years is based on a continuous varve counted chronology, the MIS3 section is tuned to the Greenland ice — both with independent age control from14C dates. Total carbon, pollen and plant macrofossils are used to synthesize a vegetation-stack, which is used together with the stacks from seasonal varve formation, flood layers, eolian dust content and volcanic tephra layers to define Landscape Evolution Zones (LEZ). LEZ 1 encompasses the landscape dynamics of the last 6000 years with widespread human influence. The natural oak and hazel forests of the early Holocene back to 10,500 b2k define LEZ 2. LEZ 3, the late glacial between 10,500 and 14,700 b2k, shows the development of a boreal forest with abundant grass and shallow water biomass in the lakes. The maximum of the last glaciation (LEZ 4: 14,700–23,000 b2k) was characterized by sparse vegetation of moss and characeae. These sediments are generally devoid of clay and sand and reveal no indication of snow-meltwater events. Accordingly, the Last Glacial Maximum (LGM) must have been extremely arid in central Europe. The sediments of the subsequent LEZ 5 from 23,000–28,500 b2k preserve distinct layers of clay and coarse sand, which indicates running water with clay in suspension and ephemeral coarse-grained fluvial sediment discharge. Abundant Ranunculaceae macroremains (used for14C dating), insects, moss and fungi sclerotia reflect a tundra environment during a time of frequent strong snowmelt events. Total carbon content,Betula–Pinuspollen and diatoms reach increased concentrations during Marine Isotope Stage (MIS) 3 interstadials that occurred between 28,500 and 36,500 b2k (LEZ 6). The entire MIS3 interstadials are well documented in the organic carbon record from the Auel dry maar. The main paleobotanical indicators of MIS3 are, however, grass pollen and heliophytes, which indicate a steppe environment with scattered/patchy trees during the interstadials. The stadial phases inferred during LEZ 6 reveal initiation of eolian dust deflation. The change of the early MIS 3 forested landscape to a steppe occurred with the LEZ 7–LEZ 6 transition. This is when modern man spread in central Europe. The principle vegetation change to a steppe at 36,500 b2k must have favoured the spread of horses, an important hunting prey of modern humans. We propose accordingly that the migration of the modern humans into central Europe might have been at least partly driven by climate and associated vegetation change. The LEZ 7 encompassed the time interval 36,500 to 49,000 b2k and was characterized by a boreal forest with high abundance of pine, birch, as well as spruce during the interstadial events. Abundant charcoal fragments indicate that this taiga was under frequent drought stress with regular burning. The most unexpected finding, but corroborated by all our maar records is the dominance of thermophilous tree taxa from 49,000 to 55,000 b2k (LEZ 8). Greenland interstadials 13 and 14 were apparently the warmest of MIS 3 according to the Eifel pollen records. The preceeding LEZ 9 from 55,000 to 60,000 b2k is also dominated by spruce, but thermophilous trees were sparse. A warm early MIS3 appears plausible, because summer insolation (at 60° N) was higher in the early MIS 3 than today, ice cover was low in Scandinavia and sea-surface temperatures of the North Atlantic were almost comparable to …

The ELSA-Vegetation-Stack: reconstruction of Landscape Evolution Zones (LEZ) from laminated Eifel maar sediments of the last 60,000 years

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