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1.
《L'Anthropologie》2021,125(4):102936
The lake basin Neumark-Nord 2 (NN 2) is located in the Geisel Valley in Saxony-Anhalt (Germany). It was scientifically investigated between 2003 and 2008. The sediment sequence, which is about 10 to 11 m thick, consists of limnic deposits, mostly silts mixed with clays and sands. Sedimentological as well as palynological, malacological and palaeomagnetic investigations, supported by absolute datings, date the entire sequence into the Eemian and Early Weichselian. Within the deposits several archaeological find horizons were discovered. Neumark-Nord 2/2 (NN 2/2) at the beginning of the Eemian and Neumark-Nord 2/0 (NN 2/0) with an early Weichselian were the most important archaeological horizons. Both find horizons represent former lake shore sites, where numerous crushed animal bones and other faunal debris were found, which can be regarded as remains of hunted game. With regard to the rich lithic material, both find horizons differ remarkably. In NN2/2, a simple artefact spectrum with a certain Levallois component and a dominance of denticulated, notched and laterally retouched specimens. In NN 2/0, on the other hand, bifacial tools such as backed knives and sometimes finely retouched scrapers are dominant, while the Levallois component fades completely into the background. Thus, NN 2 is one of the few open-air sites in archaeological landscape of Central German where several middle Palaeolithic find horizons occur in superposition.  相似文献   
2.
Aim Interpretation of fossil pollen assemblages may benefit greatly from comparisons with modern palynological and vegetation analogues. To interpret the full‐ and late‐glacial vegetation in eastern‐central Europe we compared fossil pollen assemblages from this region with modern pollen assemblages from various vegetation types in southern Siberia, which presumably include the closest modern analogues of the last‐glacial vegetation of central Europe. Location Czech and Slovak Republics (fossil pollen assemblages); Western Sayan Mountains, southern Siberia (modern pollen assemblages). Methods Eighty‐eight modern pollen spectra were sampled in 14 vegetation types of Siberian forest, tundra and steppe, and compared with the last‐glacial pollen spectra from seven central European localities using principal components analysis. Results Both full‐ and late‐glacial pollen spectra from the valleys of the Western Carpathians (altitudes 350–610 m) are similar to modern pollen spectra from southern Siberian taiga, hemiboreal forest and dwarf‐birch tundra. The full‐glacial and early late‐glacial pollen spectra from lowland river valleys in the Bohemian Massif (altitudes 185–190 m) also indicate the presence of patches of hemiboreal forest or taiga. Other late‐glacial pollen spectra from the Bohemian Massif suggest an open landscape with steppe or tundra or a mosaic of both, possibly with small patches of hemiboreal forest. Main conclusions Our results are consistent with the hypothesis that during the full glacial and late glacial, the mountain valleys of the north‐western Carpathians supported taiga or hemiboreal forest dominated by Larix, Pinus cembra, Pinus sylvestris and Picea, along with some steppic or tundra formations. Forests tended to be increasingly open or patchy towards the west (Moravian lowlands), gradually passing into the generally treeless landscape of Bohemia, with possible woodland patches in locally favourable sites.  相似文献   
3.
The Late Weichselian marine and glaciomarine sediments occurring in many places along the coast of Iceland are rich in invertebrate fossils, especially mollusks and barnacles. A diverse ichnofauna, constituted especially by bioerosional traces documenting the activity of predators and animals that use the host shell for attachment or the construction of dwellings, was identified at the localities of Ósmelur, Saurbær, and Brekkubakkar in southwestern Iceland. The ichnotaxa identified include Anellusichnus circularis (Santos, Mayoral, and Muñiz), Caulostrepsis isp., Centrichnus concentricus (Bromley and Martinell), Clionolithes isp., Finichnus peristroma (Taylor, Wilson, and Bromley), Finichnus isp., Sedilichnus asperus (Nielsen and Nielsen), Sedilichnus cf. excavatus (Donovan and Jagt), Sedilichnus gradatus (Nielsen and Nielsen), Sedilichnus smiley isp. nov., Sedilichnus ovalis (Bromley), Sedilichnus paraboloides (Bromley), Sedilichnus simplex (Bromley), and Sedilichnus spongiophilus (Müller).  相似文献   
4.
On the Taymyr Peninsula and Severnaya Zemlya Archipelago, Central Siberia, a joint German/Russian multidisciplinary research project focuses on the Late Quaternary history of climate and environment. Within the scope of this project, palynological studies were carried out on a 10.8-m core from Lama Lake, situated in the south-west of the research area. The core, which did not reach the base of the lacustrine sediments, reveals the vegetation and climate history of the last 17 000 years and demonstrates that this area was not glaciated during that time. The Pleistocene/Holocene transition is, as elsewhere in the northern hemisphere, characterized by increased temperatures during the Bølling, Allerød and Preboreal with interruptions during the Older (post-Bølling) and Younger Dryas events. The Holocene climate optimum at Lama Lake probably occurred within the Boreal period, when dense larch forests developed. The Atlantic period was characterized by warm conditions that favoured the establishment of larch-spruce forests, though a climatic deterioration is also recorded. During the Subboreal, spruce fluctuated in importance, on the basis of which it is suggested that there were two cool periods with an intervening warm period. Since 3000 B.P., the climate has become considerably cooler and forests have degenerated. During the last 1000 years, unfavourable climate conditions have resulted in a forest tundra and widespread tundra communities developing in the Lama Lake region.This paper is dedicated to Hans-Jürgen Beug on the occasion of his 65th birthday.  相似文献   
5.
The mapping of Weichselian late-glacial interstadial (13-11 ka B.P.) and Younger Dryas stadial (11-10 ka B.P.) pollen percentages for selected taxa demonstrates vegetational and hence climatic differentiation in Western Norway during these times. In the south, early interstadial Salix dominance was replaced by Betula woodland development. During Younger Dryas time, Betula pollen declined to values consistent with a modern vegetational analogue of the vegetation at the upper forest limit. In the inner fjord areas north of Stavanger, the interstadial vegetation contained scattered birch trees, the density depending on local topography and soils. During the Younger Dryas, vegetation resembling the modern mid- and low-alpine vegetation developed. On the outer coast, the interstadial vegetation was probably treeless, and dominated by Salix spp., including S. herbacea, and herbs. The vegetation became even more open during the Younger Dryas, resembling that of the modern mid- and high-alpine zones. The spatial ecotones delimiting the three areas of different vegetation development during both the interstadial and the Younger Dryas can be placed north of Stavanger, separating the southern region, and between the outer coast and inner fjord areas to the north. The Younger Dryas drop in temperature in all areas was up to about 5°C, enough to pass ecotonal thresholds in time in all areas.  相似文献   
6.
Radiocarbon dates from the terrestrial Weichselian standard profile of Oerel are presented. The end of the Early Weichselian (WE IV, corresponding to isotopic stage 5a) is dated by two independent analyses to around 61 000 years B.P. The two subsequent interstadials, Oerel and Glinde, which have been described from this locality in an earlier publication, are dated to ca. 58 000 - 54 000 B.P. and 51 000- 48 000 B.P., respectively. The dates of both interstadials are in good agreement with the chronology available from the deep sea record. The chronology of the younger part of the Pleni-Weichselian is briefly reviewed.  相似文献   
7.
We inferred past climate conditions from lacustrine sediments intercalated in Weichselian Early Glacial and Early Pleniglacial fluvial and aeolian sediments, exposed in two opencast lignite mines from the Niederlausitz area (eastern Germany). A chronology was established using radiocarbon and luminescence dating methods. Both lithology and chironomid fauna indicate that the former shallow lakes were situated on a floodplain. Palaeotemperature estimates calculated from the fossil chironomid-assemblages of the Early Glacial lacustrine deposit indicate mean July air temperatures of ca. 15 °C, which is in line with results derived in earlier studies from the Niederlausitz area and from northwestern Europe. The Early Pleniglacial lacustrine deposits consist of an organic-rich gyttja, intercalated with sand and silt lenses. The chironomid-assemblages show that a shallow meso- to eutrophic lake was present at the study site, and chironomid-inferred palaeotemperature estimates indicate an abrupt decline in July air temperatures from 15–16 °C to ca. 13 °C. In combination with other proxies from the same record, this suggests a Dansgaard/Oeschger like climate event.  相似文献   
8.
Betula fruits lacking their wings were recovered from the Gross Todtshorn borehole, Germany, covering the late Eemian interglacial, the Early Weichselian, and the Weichselian pleniglacial. In order to identify them, a data-set of seven size and shape variables was made from modern fruits of B. pubescens, B. pendula, B. nana, and B. humilis. These measurements were summarised by principal components analysis (PCA). The 140 measured fossil fruit-bodies were positioned passively on the PCA plot and identified by comparison with the dimensional envelopes of the modern species. Tree birches (B. pendula, B. pubescens) occurred in the Eemian and Early Weichselian interstadials, but not thereafter.B. nana was widespread during the intervening stadials and the Oerel interstadial. B. humilis occurred throughout the sequence, coexisting with tree birches in the Early Weichselian and with B. nana in the stadials. It usually grew on mire surfaces, in contrast to B. nana which mainly grew on mineral substrates. However, B. nana grew on peat with B. humilis in the pleniglacial Oerel interstadial, suggesting a more continental climate with cold winters. A modern analogue could be near the Ural mountains. B. humilis is presently rare in central Europe, but during the Weichselian it was well established in northern Germany. The PCA has enabled specific determination of the wingless Betula fruits, leading to vegetational and climatic reconstructions and contributing to the previously poorly known historical biogeography of Betula humilis. Received June 14, 2000 / Accepted January 2, 2001  相似文献   
9.
This paper reviews the evidence from terrestrial palaeoenvironmental records in north-central Europe and, in particular, central Germany, which relates to the controversial proposition that there were strong climate oscillations during the last interglacial (oxygen isotope substage 5e). In contrast to the evidence from the GRIP ice core at Summit, Greenland, and a recent palaeoclimate reconstruction based on the pollen profile from Bispingen, Germany, the evaluation of the palaeobotanical and the stable isotope data presented here strongly suggests relatively stable temperature for most of the Eemian and with instability confined to the beginning and end of the interglacial. High amplitude temperature variations can be seen in both the Early Weichselian pollen and isotope records. It is argued that this pattern of climate development is applicable to most of continental north-central Europe.  相似文献   
10.
Evidence from isozyme analyses indicates thatPotamogeton ×suecicus is the hybrid betweenP. pectinatus andP. filiformis. The hybrid appears to have arisen on several occasions. The isozyme profiles of this hybrid from the Rivers Wharfe and Ure in Yorkshire, south of the present limit of distribution ofP. filiformis, suggest that each population is a single clone; these clones may be relics from the Weichselian glacial period. Populations of the putative hybrid from the Rivers Tweed and Till are notP. ×suecicus but probably haveP. vaginatus andP. pectinatus as parents. If so, this is a remarkable example of a pondweed hybrid persisting vegetatively in an area outside the distributional range of one of its parents.  相似文献   
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