Boreal (climate level)
| series | Climate level |
Pollen zone |
Period |
|---|---|---|---|
| Holocene | Subatlantic | X | 450 BC Until today |
| IX | |||
| Subboreal | VIII | 3,710-450 BC Chr. | |
| Atlantic | VII | 7,270-3,710 BC Chr. | |
| VI | |||
| Boreal | V | 8,690-7,270 BC Chr. | |
| Preboreal | IV | 9,610-8,690 BC Chr. | |
| Pleistocene | |||
| Younger dryas period | III | 10,730-9,700 ± 99 BC Chr. |
The Boreal is in the earth's the second oldest period of the Holocene in Northwest Europe. It lasted from 8690 to 7270 BC. Chr.
Definition of terms and stratigraphic position
The boreal forms part of the Blytt-Sernander classification , a division of the last 14,000 years based on peat bog deposits by the Norwegian Axel Blytt and the Swede Rutger Sernander . In 1876, Blytt defined the term boreal, which is derived from the Greek god of the north wind Βορέας - boreas .
The boreal is preceded by the preboreal , followed by the Atlantic .
The boreal corresponds to the pollen zone II by WH Zagwijn and by Litt et al. 2001. or the Pollen Zone V by Franz Firbas (1949).
Based on investigations in the moors of northwestern Russia , the boreal can be divided into three parts (from young to old):
- BO-3 8500 to 8000 radiocarbon years BP or 7531 to 6903 BC Chr.
- BO-2 9000 to 8500 radiocarbon years BP or 8141 to 7531 BC Chr.
- BO-1 9300 to 9000 radiocarbon years BP or 8541 to 8141 BC Chr.
The boreal together with the preboreal form the Old Holocene .
In terms of cultural history, the Boreal corresponds to the early Mesolithic .
Chronological order
Note: Only the borders marked with a black dividing line are more or less exact; they are based on annual layers in lake sediments in north-central Europe and, strictly speaking, only apply to the climatic stages. The other boundaries are uncertain and not rigidly set. In particular, the boundary between the Middle and Young Holocene is very variable. Regarding the cultural levels, the regionally different development must be taken into account.
Climatic development
During the Holocene warm period, the boreal falls into the phase before the first temperature maximum, the early Atlantic. The rapid warming that started with the preboreal continues in the boreal as well. Towards the end of the boreal, around 7300 BC, Reached today's temperatures .
Sea level
The sea level rose slowly as the ice melted around the world: the boreal was the last period of the Holocene when England was still connected to mainland Europe. The North Sea expanded increasingly. Overall, the sea level rose during the boreal from 54 meters below sea level to almost 30 meters below sea level; this corresponds to a very high rate of around 17 millimeters / year.
Baltic region
During the Boreal, in the area of today's Baltic Sea from 8300 BC The brackish Yoldia Sea . It emerged from the former Baltic Ice Reservoir through a marine incursion in central Sweden from the North Sea area (salt water ingress between 8000 and 7800 BC via the Närke Strait ) . It had until 7500 BC. Chr. Inventory and was then due to isostatic uplift by freshening from Ancylus Lake replaced. At the beginning of the Yoldia Sea, the mirror height in the Baltic Sea was still below 40 meters below sea level, but towards the end of the boreal only 20 meters below sea level.
Flora and fauna
During the Boreal, more and more heat-loving plants grew in Northern Europe. Examples of this are the common ivy and the white berry mistletoe , which spread to Denmark during this period. Within the pollen zone V, the pioneer plants of the preboreal were increasingly replaced by pine forest in association with stocks of the common hazel ( Corylus avellana ), a community that is called pine hazel forest by palynologists . Towards the end of the boreal, the composition of the vegetation changed due to the increasing occurrence of different oak species , so that the mixed oak forest became the dominant form of forest. Pine, birch and hazel have been replaced by oak, elm , linden and alder . Species such as the broad-leaved cattail ( Typha latifolia ) grew in the moors .
The forests were populated by deer ( Cervus elaphus ), roe deer ( Capreolus capreolus ), elk ( Alces alces ), wild boar ( Sus scrofa ) and aurochs ( Bos primigenius ) who had immigrated from refuges in Italy, Spain and the Balkans. Warmth-loving species such as the European pond turtle ( Emys orbicularis ) have now even been found in Denmark. The golden plover ( Pluvialis apricaria ) penetrated as far as Norway. The predators include wolf ( Canis lupus ), brown bear ( Ursus arctos ), lynx ( Lynx lynx ) and wildcat ( Felis silvestris ). Hares ( Lepus europaeus ) were widespread. Beavers ( Castor fiber ) and otters ( Lutra lutra ) lived in wetlands and on rivers, while fish species such as pike ( Esox lucius ) and catfish (e.g. Siluris glanis ) were found in large numbers.
The man in the boreal
The boreal falls into the early Mesolithic , when people in Central and Northern Europe lived in the same settlements more often and for longer, and from there they procured their food as hunters and gatherers . Even if agriculture was already widespread in the Middle East and southern Europe , this change in northern Europe would not take place until thousands of years later. This is attributed to the fact that the forest provided sufficient food, so that only small areas were cleared by fire.
Among other things, due to the archaeological site of Vis I on the Wytschegda , some details of the life of the people during the boreal have become known. The residents of the settlement were able to make baskets and nets out of plant fiber, and finds of paddles mean that regular boat tours are closed. In winter, sledges were used as a means of transportation. Weapons such as bows, arrows and spears were found and everyday objects were decorated with motifs such as snakes, people and animals.
The culture bearers of the early Mesolithic are the Maglemose culture in Denmark and the Creswellia (up to 8000 BC) in England . The Haltern level in North Rhine-Westphalia did not begin until the end of the Boreal (from 7400 BC). In the Levante already that prevailed Neolithikum , as its support culture the Preceramic Neolithikum B (8800-7000 v. Chr.) Acted.
In North America from 8900 BC. The Folsom culture (ended around 8200 BC) was established before the beginning of the Boreal . Around 8500 BC The Middle Paleo-Indian period came to an end. It was superseded by the late Paleo-Indian period , which lasted until 8000 BC. Lasted. This was followed by the Early Archean , which was to endure into the Atlantic (6000 BC). The Late Paleo-Indian San Dieguito Complex in the southwestern United States and northwestern Mexico is dated 8200 BC. Dated. From 6000 BC it was followed by The La Jolla Complex .
The Paleo-Indian and Archaic cultures of North America are possibly responsible for the extinction of the American mastodon Mammut americanum between 10,000 and 7,000 BC. Responsible.
Volcanic eruption
By a volcanic eruption in Iceland resulting tephra of Saksunarvatn is an important stratigraphic marker horizon in the early Boreal. It is in Greenland on 10 297 ± 45 BP in lake sediments from Kråkenes cal in Norway on 10 210 ± 35. BP and v in northwestern Germany lakes on 8140 . Dated.
See also
Individual evidence
- ^ Geozentrum Hannover : Structure of the Holocene. ( Memento of the original from May 10, 2015 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. (PDF, 405 kB)
- ↑ A. BIytt: Immigration of the Norvegian Flora . Alb. Cammermeyer, Christiania (Oslo) 1876, p. 89 .
- ↑ Waldo Helio Door Zagwijn : Nederland in het Holoceen . In: Rijks Geologische Dienst Haarlem (Ed.): Geologie van Nederland . Deel 1. Staatsuitgeverij, 's-Gravenhage 1986.
- ↑ T. Litt, A. Brauer, T. Goslar, J. Merkt, K. Balaga, H. Müller, M. Ralska-Jasiewiczowa, M. Stebich & JFW Negendank: Correlation and synchronization of Lateglacial continental sequences in northern central Europe based on annually laminated lacustrine sediments . In: Quaternary Science Reviews . tape 20 , 2001, p. 1233-1249 .
- ^ S. Björck: A review of the history of the Baltic Sea, 13.0-8.0 ka BP . In: Quaternary International . tape 27 , 1995, p. 19-40 .
- ↑ Anja Broszinski: The subfossil diatom flora of the western Baltic Sea. Dissertation from the Johann Wolfgang Goethe University . Frankfurt am Main 2002.
- ^ JAA Bos: Aspects of the Lateglacial-Early Holocene vegetation development in Western Europe. Palynological and palaeobotanical Investigations in Brabant (the Netherlands) and Hessen (Germany) . In: LPP Contributions Series . tape 10 . Utrecht 1998 (dissertation).
- ↑ GM Burov: The wooden tools of the settlement area Vis I as the basis for the periodization of the Mesolithic in the north of the European part of the USSR . In: PM Vermeersch and P. van Peer (eds.): Contributions to the Mesolithic in Europe . University Press, Leuven 1990, pp. 335-344 .
- ↑ GM Burov: On Mesolithic Means of water transportation in northeastern Europe . In: Mesolithic Miscellany . tape 17 , no. 1 , 1996, p. 5–15 ( ( page no longer available , search in web archives: arcl.ed.ac.uk )).
