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1.
In the area of archaeological excavations that were performed prior to the construction of Main Road No. 86 in Vas County (West Hungary) in the Alpine foreland new geoarchaeological analyses have been conducted. We used anthracology and pollen analyses to reconstruct the former vegetation cover at the study site. Charcoal data provide site-related information about the local woodland composition, management and human impact, while pollen data provide information on the arboreal and non-arboreal vegetation on a regional or local scale. Adequate samples for anthracological analyses derive from the Bronze Age, Iron Age, Imperial and Migration Periods and Middle-Ages archaeological objects. The core for pollen analyses originates from alluvial sediments of the Borzó Creek and covers the late Pleistocene and the Holocene until the Medieval Period. Charcoal analyses show the dominance of Quercus trees in the vicinity of the human settlements that might indicate a strong human selection, or the fragmentation of samples. Pollen analyses indicate thermophilous vegetation from the beginning of the Holocene, with increasing values of Fagus and Carpinus. Pollens of cereals indicate human activity, which is also demonstrated by the presence of pollen from Juglans and Vitis in the Iron Age sequence. Extensive forest clearance occurred in the Late Iron Age and the Imperial Period.  相似文献   

2.
The Holocene sediment of Lago Piccolo di Avigliana (Piedmont, Italy, 356 m a.s.l.) was dated by 14C and analysed for pollen to reconstruct the vegetation history of the area. The early‐ and mid‐Holocene pollen record shows environmental responses to centennial‐scale climatic changes as evidenced by independent palaeoclimatic proxies. When human impact was low or negligible, continental mixed‐oak forests decreased at ca. 9300 BC in response to the early‐Holocene Preboreal climatic oscillation. Abies alba expanded in two phases, probably in response to higher moisture availability at ca. 6000 and ca. 4000 BC , while Fagus expanded later, possibly in response to a climatic change at 3300 BC . During and after the Bronze Age five distinct phases of intensified land use were detected. The near synchroneity with the land‐use phases detected in wetter regions in northern and southern Switzerland points to a common forcing factor in spite of cultural differences. Increasing minerogenic input to the lake since 1000 BC coincided with Late Bronze—Iron Age technical innovations and probably indicate soil erosion as a consequence of deforestation in the lake catchment. The highest values for cultural indicators occurred at 700–450 and at 300–50 BC , coinciding with periods of high solar activity (inferred from Δ14C). This suggests that Iron Age land use was enhanced by high solar activity, while re‐occupation of partly abandoned areas after crises in earlier periods match better with the GRIP stable isotope record. On the basis of our data and comparison with independent palaeoclimatic proxies we suggest that precipitation variation was much more important than temperature oscillations in driving vegetation and societal changes throughout the Holocene. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

3.
Vegetation and lake-level data from the archaeological site of Tresserve, on the eastern shore of Lake Le Bourget (Savoie, France), are used to provide quantitative estimates of climatic variables over the period 4000–2300 cal BP in the northern French Pre-Alps, and to examine the possible impact of climatic changes on societies of the Bronze and early Iron Ages. The results obtained indicate that phases of higher lake level at 3500–3100 and 2750–2350 cal BP coincided with major climate reversals in the North Atlantic area. In west-central Europe, they were marked by cooler and wetter conditions. These two successive events may have affected ancient agricultural communities in west-central Europe by provoking harvest failures, more particularly due to increasing precipitation during the growing season. However, archaeological data in the region of Franche-Comté (Jura Mountains, eastern France) show a general expansion of population density from the middle Bronze Age to the early Iron Age. This suggests a relative emancipation of proto-historic societies from climatic conditions, probably in relation to the spread of new modes of social and economic organisation.  相似文献   

4.
The alluvial deposits near Gibala-Tell Tweini provide a unique record of environmental history and food availability estimates covering the Late Bronze Age and the Early Iron Age. The refined pollen-derived climatic proxy suggests that drier climatic conditions occurred in the Mediterranean belt of Syria from the late 13th/early 12th centuries BC to the 9th century BC. This period corresponds with the time frame of the Late Bronze Age collapse and the subsequent Dark Age. The abrupt climate change at the end of the Late Bronze Age caused region-wide crop failures, leading towards socio-economic crises and unsustainability, forcing regional habitat-tracking. Archaeological data show that the first conflagration of Gibala occurred simultaneously with the destruction of the capital city Ugarit currently dated between 1194 and 1175 BC. Gibala redeveloped shortly after this destruction, with large-scale urbanization visible in two main architectural phases during the Early Iron Age I. The later Iron Age I city was destroyed during a second conflagration, which is radiocarbon-dated at circa 2950 cal yr BP. The data from Gibala-Tell Tweini provide evidence in support of the drought hypothesis as a triggering factor behind the Late Bronze Age collapse in the Eastern Mediterranean.  相似文献   

5.
Pollen data indicate Tilia was an important component of the primary woodland cover of many lowland areas in northern and central Europe. High values recorded in mid-Holocene pollen diagrams are generally followed by well-defined declines. In this study the palynological, spatial and temporal trends associated with declines in Tilia pollen at sites from lowland Britain are assessed to evaluate the nature and relative importance of the processes responsible. Processes primarily related to the depositional environment (paludification, marine inundation, breaks in sedimentation) and percentage representation of pollen data play the dominant role in 44% of the 164 declines included in the study. Anthropogenic activity can account for the remainder. Tilia rarely recovers from low values after anthropogenic declines, suggesting such declines have the potential to elucidate patterns in the destruction of primary woodland across lowland Britain. Other than declines associated with the mid-Holocene Ulmus decline event, few anthropogenic Tilia declines have been reliably dated prior to c. 5000 cal. BP. Tilia largely disappeared from areas with calcareous and loamy soils as a result of clearance activity in the period 5000–3000 cal. BP (Late Neolithic to Late Bronze Age). Between 3000 and 2500 cal. BP few declines are recorded suggesting a link between clearance activity and climate change. Later declines are concentrated on the sandier lithologies and often associated with heathland formation. The scarcity of declines after 2000 cal. BP is likely to be related to the exhaustion of primary woodland.  相似文献   

6.
Discriminant functions link vegetation zones and surface pollen along the woodland–steppe ecotone in northern China. These links were utilised to reconstruct palaeovegetation using fossil pollen data from four lake sediment sites within the ecotone. Holocene movements of the vegetation zones were derived from the above results and were interpreted as the results of climatic, topographic and edaphic factors. This study shows that climatic change was the driving factor for ecotonal movement, but that the positions of vegetational zones were nevertheless controlled by topographical and edaphic conditions, and consequently boundaries between different vegetational zones responded individualistically. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

7.
Paleoecological records from two Holocene peat bogs in northern Germany are linked by two microscopic volcanic ash layers, correlated by petrology and geochemistry to explosive volcanism on Iceland. The younger “Microlite tephra” cannot be correlated to any known eruption, while the older tephra layer is identified as a deposit of the Hekla 3 eruption. The tephra layers are dated by an age–depth regression of accelerator mass spectrometry 14C ages that have been calibrated and combined in probability distributions. This procedure gives an age of 730–664 cal yr B.C. for the “Microlite tephra” event and 1087–1006 cal yr B.C. for the Hekla 3 event. Accordingly, the tephra layers were deposited during the late Bronze Age. At this time, human settlement slowly increased pressure on the environment, as indicated by changes in woodland pollen composition at the two bogs. The tephra-marker horizons further show that the palynologically defined transition from the Subboreal to the Subatlantic Period is synchronous in the investigated area. However, the macroscopic visible marker in peat, the change from fibrous to sapric peat, the “Schwarztorf-Weißtorf-Kontakt,” is asynchronous. Bog vegetation did not immediately react in unison to a climatic change at this pollen zone boundary; instead, the timing of vegetation change depended on the location within the bog.  相似文献   

8.
An excavation primarily intended to investigate the Bronze Age deposits at Hautrive‐Champréveyres, Neuchâtel, Switzerland, encountered beneath the Bronze Age levels a sequence of Late‐glacial sediments that were deposited between about 13000 yr BP and 11800 yr BP. Within these deposits Upper Palaeolithic hearths, bones and flint implements were found in a context that left no doubt that they accumulated on the actual living floors. Two separate cultures were involved; an earlier Magdalenian one overlain by a rather later Azilian assemblage. Coleoptera from the associated organic silts and sands provide detailed ecological and climatic information about the time when these people lived in the area. Radiocarbon dates indicate that the Magdalenians lived in the area at about 13000 yr BP. The Coleoptera show that the mean July temperature at this time was about 9°C and mean temperature of the coldest month was about −25°C. The landscape was bare of trees with an open patchy vegetation. Shortly after the area was abandoned by the Magdalenian hunters, the climate became suddenly warmer and mean July temperatures rose abruptly to at least 16°C and winter temperatures rose to levels not much different from those of the present day. There is evidence that at this time, intense slope instability and mud flows may have rendered the locality unsuitable for human occupation. About seven centuries after the episode of sudden climatic warming, namely at about 12300 yr BP, palaeolithic Azilian hunters occupied the area at a time when the climate was thoroughly temperate and the landscape was clothed in birch and willow woodland. This was gradually replaced by pine forest at the top of the sequence and Late‐glacial deposition ceased by about 11800 yr BP. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   

9.
Interpreting how environmental dynamics respond to global climate change and how this has affected human evolution and dispersal is an on-going topic of debate. During the early Middle Pleistocene (～0.6–0.4 Ma), as compared to earlier, environmental conditions were relatively more stable, with longer climatic cycles alternating between open and forested landscapes. During this interval, humans spread successfully providing an important number of fossil sites where fossils or tools are reported. The Atapuerca-Sima de los Huesos (Burgos, northern Spain) site (Atapuerca-SH) is one of the earliest localities with hominin evidence in the European Middle Pleistocene, with the most important accumulation of Homo heidelbergensis so far. We have analyzed the abundant faunal record from Sima de los Huesos, which is mainly comprised of carnivores, in order to approach an interpretation of the palaeoenvironmental circumstances where these hominids inhabited within the Sierra. Other sites from Sierra de Atapuerca referred to the same Faunal Unit (FU 6), are roughly contemporaneous, and include important ungulates, which are here analyzed with Atapuerca-SH. Additional information provided by isotopic analysis helps elucidate the ancient ecology of taxa present in Sima de los Huesos allowing for an accurate portrayal of the setting in which humans lived. The timing of the spread of Homo heidelbergensis is dominated by a relative climatic and environmental stability and points to a landscape dominated by savannah-like open woodland.  相似文献   

10.
The Bronze Age paleohydrography of the distal Adige and Po alluvial plain (northeastern Italy) is notable for its relations with protohistoric human activities in this area. This paper regards the stratigraphy and petrography of the Saline–Cona alluvial ridge, upon which the Saline, Sarzano, and Cantarana Bronze Age sites lie, and the petrography of Fratta alluvial ridge, upon which the Frattesina complex (Bronze–Iron Age) lies. Sand analyses indicate the Po River as the source for sediments underlying the alluvial ridge that runs through Fratta Polesine, Rovigo, Sarzano, and Cona. Radiometric ages indicate that the branch of the Saline–Cona ridge was formed by the Po River between the second half of the 3rd millennium B.C. and the end of 2nd millennium B.C. This ridge represents the maximum northward expansion of the Po alluvial system, through the same area of coastal plain crossed by the Adige and Brenta paleochannels. This paleohydrographic setting implies that fluvial connections between the Central Po Plain settlements, the Venetian Plain and Alps were relatively less complex in the Early and Middle Bronze Age than in the Late Bronze Age, when the terminal reach of the Po River was separated by the Adige River by hundreds of km2 of swampy terrain. © 2009 Wiley Periodicals, Inc.  相似文献   

11.
The results of detailed pollen‐analytical investigations of a core from Lough Dargan, Co. Sligo, Ireland are presented. The pollen diagram spans much of the postglacial and documents changes in woodland composition and cover, and farming activity. Special attention is paid to prehistoric farming and to the significance of cereal‐type pollen. The first sign of arable farming coincides with the Elm Decline at c. 3760 BC. This early Neolithic farming phase extended over c. 750 years, the main Landnam phase having a duration of ～700 years. After a break of about three centuries, Neolithic farming resumed. Late Neolithic farming was at first predominantly pastoral, but later (c. 2360–2130 BC) it had a distinct arable component. In the early Bronze Age, beginning c. 2130 BC, farming increased and woodland was substantially reduced for the first time. From then until the beginning of the late Iron Age (c. 80 BC), there was a sustained and strong human impact. In the late Iron Age, a distinct lull in pastoral farming lasted for about four centuries (c. 80 BC–AD 350). This facilitated woodland regeneration that included yew. Substantial woodland clearance, and farming that included a considerable arable component, characterized the Medieval and later periods. The changes recorded at L. Dargan and other sites in the region are discussed in the light of evidence for climate change provided by regional and super‐regional climate proxies. It is argued that climate may not have been a decisive factor in determining human impact and farming activity.  相似文献   

12.
Palynological data on major Holocene climatic events in NW Iberia   总被引：6，自引：0，他引：6  
Three NW Iberia Cantabrian Mountain pollen records are presented. They reflect the main Holocene climatic shifts in the North Atlantic region as recorded in the isotopic data from Greenland ice, Irish speleothems and reconstructed sea surface temperatures. Two brief forest regression episodes reconstructed from pollen may be synchronous with GH-11.2 and GH-8.2 events. At mid-altitude, two woodland expansion phases (7000-6000 14C yr BP and 4000-2500 14C yr BP) are separated by a phase of heaths and peat deposits. Major woodland declines occurred during the Galician-Roman Period (which includes the Bronze Age, the Iron Age and the Roman occupation) and from the end of the Medieval Period. The pollen data, backed up by archaeological and historical sources, suggest climatic impact of the Iron Age Cold Period, but are indecisive concerning the Little Ice Age. However, the pollen records do not support any significant 'Neoglacial' period (4000-3000 14C yr BP) influence on NW Iberia.  相似文献   

13.
Pollen analyses of three sediment cores performed on the archaeological lake dwellings of Chindrieux and Tresserve (Savoie, France), on the eastern shore of Lake Bourget, enable the reconstruction of vegetation history and human impact during the Bronze Age. Results show a good correlation between lake-level fluctuations and the evolution of anthropogenic indicators. The end of the Neolithic period and the early Bronze Age are characterised by a discreet occupation of the Lake Bourget surroundings, in spite of a warmer climatic condition. The middle Bronze Age, contemporaneous with wetter and cooler conditions, is related to a decrease in pollen of cultivated plants and weed. Farming activities reappear in the late Bronze Age and human impact increases suddenly at the very end of the late Bronze Age. Three anthropogenic phases are clearly visible: a short decrease in anthropogenic indicators and a high lake-level phase occur in the middle of this period of intense farming development. A new decrease in human impact appears at the beginning of the Iron Age.  相似文献   

14.
The region of eastern Oman (called Ja’alan) is often compared to the Arabian deserts, which are typically arid and depopulated areas. Today, this geographical definition is correct: the geographic and climatic conditions (low precipitation, pronounced dryness, high evaporation) indicate an arid region, and the area is sparsely populated. Between the Neolithic and the Early Bronze Age, the geographic and climatic conditions did not change much, and were slightly more humid than at present. Although the term “green Ja’alan” does not describe this area, we observe that the region was occupied by a quite substantial population. Since 1985, surveys and excavations have been carried out and more than 4000 archeological structures are now listed. The spatial distribution of these sites differs for each period, from Neolithic seasonal camps to oasian settlements of the Early Bronze Age.  相似文献   

15.
《Quaternary Science Reviews》1999,18(4-5):711-716
Charcoal analysis of three archaeological sites in southern Syria in the vicinity of the Jebel al Arab (formerly Jebel Druze) indicates that during the Early Bronze Age an association consisting predominately of Pistacia, deciduous oak and almond was exploited. During the Middle Bronze Age these taxa diminish and are partially replaced by more steppic species or introduced wood such as olive. During the Roman period evergreen oak appeared in the region and gradually replaced the deciduous oak which is now restricted to a small area. The gradual replacement of deciduous oaks by evergreen oaks has been observed in other areas of the Mediterranean basin during the Holocene. Conifer charcoal such as pine and cedar is present on the sites, but it is not clear whether these were local or imported from farther away, for example, the Lebanese highlands. During the Middle Bronze Age olive wood was also used as combustible but here also its exact origin is not known.  相似文献   

16.
Three archaeological sites of the Bronze and Early Iron Ages were investigated using palynological methods. To interpret the fossil spectra more accurately, recent pollen from alluvium, surface soil and cultural layers within modern villages were also studied in the area. During the time interval when the ancient cultural layers accumulated, thinned-out birch forests were replaced by mixed coniferous and broad-leaved trees. This might have been caused by climatic transition which possibly influenced the changing cultural traditions within the area. The climatic transition also includes a change in humidity. The wettest stages are recorded by pollen data during the transition period between the Bronze and Early Iron Age. This corresponds to the Subboreal/Subatlantic boundary within the European Holocene (around 2500 yr B.P.). © 1994 John Wiley & Sons, Inc.  相似文献   

17.
The La Parte (Asturias) northern Spain site contains a cold-adapted mammal faunal assemblage that corresponds to a level radiometrically dated to a minimum age of 150 ka. It represents the most ancient site with cold resistant fauna in the Iberian Peninsula.Among the species recorded in La Parte, Coelodonta antiquitatis and Rangifer tarandus represent the typical cold-adapted large mammal association.The presence of the woolly rhino at La Parte provides relevant environmental information about the Mammoth Steppe. This species was not as abundant in the Middle Pleistocene as during the Late Pleistocene, when its cold-adapted features can be studied from an evolutionary perspective. The remains attributed to R. tarandus suggest an open steppe ecosystem.The presence of Marmota sp. is also confirmed in La Parte. A first interpretation would suggest an alpine or periglacial ecosystem, but based on recent results which do not support the correlation between phylogeny and climatic tolerance for extant species of Marmota (López and Cuenca, 2002. Palaeogeography, Palaeoclimatology, Palaeoecology 186, 311), we propose the presence of this rodent suggests an open landscape with cold conditions.The rest of the taxa included in the La Parte assemblage (Crocuta crocuta, Panthera leo, Cervus elaphus, Megaloceros cf. giganteus, Bison priscus and Equus caballus) are usually associated with typical cold-adapted faunas, but they are also found in woody temperate zones so they do not characterize by themselves a cold period. The faunal association from La Parte suggests a combination of steppic and open woodland ecological conditions.  相似文献   

18.
Archaeological research in the Upper Mississippi River valley between 43°EN and the St. Croix River confluence (44.7°EN) has produced a series of large Oneota villages from which corn (Zea mays) has been recovered. Radiocarbon determinations indicate that the sites in the northern reach of this study area date from AD 1010 to 1440. These sites are characterized by large village areas and associated mound groups. Unlike villages in the northern region, sites in the LaCrosse area are more extensive, and burial mound complexes are absent. the southern villages have 14C dates ranging from AD 1030 to 1520. Based on the differences in community plans and artifact assemblages, it is suggested that the northern Oneota groups are not ancestors of the neighboring LaCrosse variant. Historical documents for Europe indicate that at similar latitudes, the climate began to deteriorate after AD 1300. With the onset of cooler summers characteristic of the Neo-Boreal climatic episode, corn agriculture became unreliable in the northern portion of the Mississippi basin after AD 1400. In response to the unfavorable climatic conditions, large semi-permanent villages were abandoned and an outward migration began. the peak cold at ca. AD 1550 (the “Little Ice Age”) caused the collapse of agriculture in the LaCrosse region as well. Historical documents, archaeological evidence, and palynological data indicate that the climatic “recovery” did not ensue in this region for more than two centuries. After AD 1750 climatic conditions were again favorable for the cultivation of aboriginal corn.  相似文献   

19.
Plant and insect macrofossil assemblages dating to the full-glacial (late Wisconsinan) are rare from eastern Beringia. Here we present an assemblage of fossil pollen, insect and plant macrofossils recovered from alluvium at the Bluefish Exposure, northern Yukon Territory. Nine AMS radiocarbon ages place these data between ca. 18,880–16,440 14C yr BP (22,313–19,597 cal. yr BP). These data indicate that xeric steppe, rich in bunchgrasses Poa and Elymus, Artemisia frigida and diverse forbs was interspersed within a mosaic of local vegetation types, including mid-rich fens, mesic graminoid meadows, steppe-tundra and herb-tundra. Macrofossils and minor pollen of tundra forbs suggest steppe-tundra plant associations within midslope elevations and discontinuous herb-tundra on high elevation uplands on exposed bedrock ridges. The composition and distribution of local vegetation was dependent on available moisture, drainage, aspect and elevation. Compositional and physiognomic similarities can be made with extrazonal steppe-dominated dry slopes and high elevation steppe-tundra ecotones in central Alaska and Yukon Territory. Our paleoecological data reflect environments inhabited by the diverse late Pleistocene Bluefish Caves fauna, including woolly mammoth, horse, steppe bison, and saiga antelope.  相似文献   

20.
Two conflicting stratigraphic schemes describe the Siberian Karginskii interstade (Oxygen Isotope Stage 3 equivalent) as having: 1) relatively stable climate with environments more similar to the full glaciation; or 2) variable climate with landscapes that more closely approximate contemporary ones. New data from continuous lake cores and a nearly continuous section from western Beringia (WB) suggest that both schemes are valid. Herb-dominated communities, possibly with isolated populations of Larix, characterized northern WB with only a slight shift from relatively warm to cool summers during the mid-interstade. In contrast, herb and shrub tundra, steppe, forest-tundra, and modern Larix forest occurred at various times in areas of southern WB, suggesting greater climatic instability. A thermal optimum is evident in the south during the mid-interstade, with modern vegetation in southeastern WB and Larix forest-tundra in the southwest. Variations in Pinus pumila pollen indicate summer warm/winter dry and summer warm/winter wet conditions in southeastern WB. These fluctuations contrast to other areas of WB, where summers and probably winters were consistently arid. Although the interstade presents a unique interval within the Late Pleistocene, paleodata and paleoclimatic models suggest that changes in marine conditions, including sea level, were likely key drivers in the regional climate history.  相似文献   

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