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1.
Human impact on mid- and late Holocene vegetation in south Cumbria, UK   总被引:2,自引:0,他引:2  
The use of 9 pollen sampling sites and 56 14C dates has identified hitherto unsuspected or poorly-defined sequences of mid- to late Holocene (late Neolithic to post-Medieval) anthropogenic vegetation changes in south Cumbria, U.K. A series of small-scale, but significant woodland clearance episodes are recorded throughout the Bronze Age, followed by a marked recession in activity during the early Iron Age. The late Iron Age-Roman periods witnessed the first major clearance of woodland in the region which was succeeded by woodland regeneration in the post-Roman/early Medieval period. Woodland clearance intensified in the later Medieval period culminating in large areas of permanently open landscape. The results show that high-resolution, independently date pollen analysis is necessary to reveal regional evidence of small, temporary Bronze Age clearances. A well-documented prehistoric wooden trackway from Foulshaw Moss is shown to be significantly older than previously thought, dating to the mid-Bronze Age, ca. 1550–1250 cal B.C. Pre-Roman cereal cultivation in the area is also confirmed.The Department of Earth Sciences  相似文献   

2.
Deciduous woodland can be reconstructed as the potential vegetation cover of most parts of the Chernozem (black earth) loess areas settled by the early Neolithic farmers of the Bandkeramik culture in the sixth millennium b.c. The character of the woodland as closed, with few light-demanding plants, or more open is very important for the potential of an agricultural system. Botanical results are not able to indicate the composition of the woods quantitatively, but they can give indirect hints. It is discussed whether these archaeobotanical results, in combination with the characteristics of the wild and domesticated herbivores identified, can be interpreted with regard to the density of the woodland cover in Neolithic times. The use of the floodplains as pasture is interpreted from pollen analytical results.  相似文献   

3.
The High Weald is an unusually well-wooded area in southern England. A high proportion of this woodland is ancient, being formerly exploited as seasonal pasture and coppice. Multiple pollen profiles from the Rye area have been used to elucidate the origins of this cultural landscape. By combining sites with small and large pollen source areas, both local and regional patterns of vegetation change have been determined. The mid-Holocene Tilia-dominated woodlands were subjected to temporary clearance as early as the Neolithic. This woodland was more extensively exploited over a ca. 700 year period from the beginning of the Bronze Age. The main elements of the modern landscape (woodland, pasture and limited cultivation) can be traced back to a more intensive phase of human activity, which commenced in the late Bronze Age. A regional increase in Fagus sylvatica pollen ca. 750 B.C. probably reflects the use of the Wealden woods for pasturage. There is no palynological evidence that the fuel demands of the Roman iron industry resulted in widespread woodland destruction. The early Anglo-Saxon period appears to have been one of land-use continuity, with a second increase in Fagus pollen at ca. A.D. 700 corresponding to historical evidence for the presence of wood-pastures in the Weald.  相似文献   

4.
Agrarian history and local cultural landscape dynamics have been documented through pollen analysis of a peat core within the hamlet of Yttra Berg, which is situated in an upland area of southwest Sweden. The sequence covers the last 5,000 years, from Neolithic to modern time. Wood pasturing started at 2000 b.c., followed by grazing and small-scale cultivation with 500 year cycles from 650 b.c., and permanent fields of agriculture from a.d. 1150. The area was abandoned during the period a.d. 1350–1550. Three cycles of succession related to land-use have been identified for the period 650 b.c. to a.d. 1550. Correlation with frequent clearance cairns in the area is discussed. Recessions of agriculture/settlement during the late Middle Ages and late modern time are documented. Pollen data indicate increased landscape and plant diversity since the Neolithic, closely linked to openness of the agrarian landscape. These results are important for landscape restoration.  相似文献   

5.
Early and mid Holocene local vegetational history, with special reference to woodland communities, was revealed by pollen analysis of a radiocarbon dated lake sediment profile from Lake Miłkowskie (Jezioro Miłkowskie) in northeastern Poland. The main factor controlling the dynamics of woodland composition changes until ca. 1950 b.c. was climate. After that, the role of human activity became increasingly important. The results of high-resolution pollen analyses provide evidence for early woodland disturbances caused by Mesolithic people at ca. 6950 b.c. Several episodes of human impact, differing in scale, and separated by subsequent episodes of woodland regeneration/stabilization were noted. The first traces of local crop farming, shown by the presence of Cerealia pollen, were recorded at ca. 3800 b.c. in the Paraneolithic/Neolithic period. Animal husbandry as well as cereal cultivation played only a marginal role in the economy, which was traditionally based on hunting, fishing and gathering through the Neolithic and the early Bronze Age. The change in economic strategies from foraging towards farming, starting around 3750 b.c., was a long-lasting process. An increase of productive economy took place in the middle Bronze Age at ca. 1400 b.c.  相似文献   

6.
In this article, we discuss the Neolithic and Early Copper Age (ECA) part of two pollen records from the Middle Tisza Floodplain in association with the local archaeological settlement record. We address the hypothesis of Willis and Bennett (2004) that there was little human impact by farmers on the environment of SE Europe until the Bronze Age. Contrary to this hypothesis, our results show that small-scale agriculture and woodland clearance is already attestable in the earliest Neolithic in Eastern Hungary, there are signs of expanding scale of mixed farming in the Middle Neolithic and strong evidence for extensive landscape alterations with enhanced pasturing and mixed farming in the Late Neolithic (LN) and ECA. The main vegetation exploitation techniques in the alluvial plain of Sarló-hát were selective tree felling (mainly Quercus), coppicing (mainly Corylus and Ulmus) and woodland clearance to establish grazing pastures and small-scale crop farming. Comparison with other well-dated pollen diagrams from Eastern Hungary suggested that, in the Early and Middle Neolithic (8000–7000?cal.?b.p.), Corylus and Ulmus coppicing were probably frequent, while pastoral activities and associated woodland clearance is distinguished in the LN (7000–6500?cal.?b.p.). Our data also suggested a shift to moister summer conditions in the alluvium during the ECA, which may have contributed to a trend towards settlement dispersion and increased reliance on animal husbandry in the NE Hungarian Plain.  相似文献   

7.
Mid-Holocene vegetation diversity in eastern Cumbria   总被引:4,自引:0,他引:4  
The concept of biodiversity can operate at several different ecological levels from that of the Global ecosystem to the genetic diversity of a single species. This paper focuses on the beta-type diversity of vegetation communities at the intra and inter-regional scale, using five mid-Holocene (Neolithic) pollen diagrams from eastern Cumbria (c. 500 km2 centred on the Eden valley). The sites were selected in order to include the variation in both soil/rock type and altitude within the study area, ranging from the Eden valley and southern limestone plateau to the foothills and summits of the western edge of the Pennines. The local pollen component which is dominant in these small sites, is used to determine intra-regional vegetation diversity for a time-slice in the Neolithic. Simple statistical methods are used to compare sites and as a measure of intra-regional vegetation-type diversity. This is compared with estimates of the community diversity for the British Isles during the same period. The results suggest that the intra-regional vegetation diversity is comparable to that of Northern England, and it is related to variation in both altitude and soil type. There are some differences, for example the steepness of the western face of the Pennines is probably responsible for a lack of the pine dominated zone, and pedological constraints probably prevented the full development of woodland on the limestone plateau at the south of the study area. The open landscape of the limestone plateau acted as a refuge for late glacial herbaceous taxa prior to their re-expansion into the wider landscape after widespread deforestation and arable cultivation. The results have implications for both the mapping of past vegetation at the national scale and for landscape archaeology.  相似文献   

8.
The results of pollen analyses from the top 8 m of sediment retrieved from Quidenham Mere, Norfolk, UK are presented. These, together with the results of charcoal analyses and the numerical classification of the pollen and spore taxa into ‘recurrent groups’ using simple discriminant function analysis, are used to reconstruct the vegetation history of the Quidenham Mere catchment over approximately the last 8000 years and to infer anthropogenic effects on the landscape. After some minor woodland clearance in the Bronze Age and further clearance in the Iron Age, it was only in the Anglo-Saxon period that most of the woodland was cleared. Although arable farming was important, it appears that there was also a considerable amount of land used for grazing, with grazed woodland and wood pasture. Towards the top of the sequence, within the past 200 years, there is evidence of the foundation and development of the Quidenham Hall parkland adjacent to the site, with the planting of native and exotic species of trees. A comparison is made between the vegetation histories and anthropogenic effects on the landscapes of Quidenham Mere and Diss Mere, a similar lake about 10 km from Quidenham. Both sites reflect the agricultural practices occurring in their catchments from early times. Exceptionally high values of Cannabaceae grains are indicative of retting of hemp during the past 1500 years. Rarefaction analysis is used to compare the pollen richness of the two sites.  相似文献   

9.
An interdisciplinary palaeoecological study in the low-alpine and subalpine zones of Val Febbraro, upper Valle di Spluga (Italy), between 1830 and 2304 m a.s.l., suggests the temporary presence of early Neolithic groups at about 6000 uncal b.p. Evidence for local woodland clearance and charcoal dust were found. Phases of woodland and treeline disturbances, and indications of increased human presence are evident at about 5500, 5100, and 4000 b.p. A marked increase in disturbance, mainly related to pasturing, is dated to the beginning of the Bronze Age. The last major stage of human impact on the vegetation coincides with the Final Bronze phase and the beginning of the Iron Age, with a small temporary reduction during the Roman period. 14C dated archaeological sites and finds are broadly concordant with the phases of human impact on the vegetation. A summary figure is presented. No locally significant climatic changes have been traced during the last 6000 years, and if present, they are probably overshadowed by the vegetational changes caused by human activity. Communicated by F. Bittmann  相似文献   

10.
Pollen, micro-charcoal and non-pollen palynomorph (NPP) data from the mid Holocene Ulmus decline and the preceding millennium have provided evidence of repeated fire disturbance of the upland woodland at Bluewath Beck Head, on the North York Moors in northeast England. Woodland disturbance coincides with the Ulmus decline, which at several similar upland sites in northern England is dated to ca. 4800 uncal b.p. (ca. 5550 cal b.p.), and so to the early Neolithic period. Two fire events occur within a cycle of disturbance and regeneration between about 6100 (ca. 6950 cal b.p.) and 5700 b.p. (ca. 6475 cal b.p.), placing them in the later stages of the Late Mesolithic hunter-gatherer occupation of the upland and near the start of the transition to early Neolithic agricultural economies. Increased Melampyrum and Corylus pollen percentages characterise the post-fire vegetation response. These disturbances probably resulted from human activity, suggesting that fire was an integral part of the Late Mesolithic ecology. The local origin of some NPPs greatly enhances the palaeoecological interpretation, showing variations in the hydrological responses to disturbance that are much less visible in the pollen record, and helping to distinguish between local and regional vegetation changes. Other NPPs indicate burning near to the site. A substantial peak in spores of the wood-rot fungus Kretzschmaria deusta across the Ulmus decline may indicate girdling and other woodland management techniques as part of Neolithic woodland farming.  相似文献   

11.
Wood charcoal analysis from Kovacevo in southwest Bulgaria, one of the earliest Neolithic sites in southeastern Europe, provided information about the first stages of anthropogenic impact on vegetation during the Early Neolithic (6159–5630 cal b.c.). Deciduous oak was the most abundant and frequently used taxon in the wood charcoal assemblages. Cornus charcoal was also abundant, probably connected with the use of its twigs as building material in wattle and daub structures. The dominant deciduous oak forest was opened during the Kovacevo I period, as shown by evidence from the Kovacevo Ia and Kovacevo Ib occupation phases. Other types of vegetation, like Black pine (Pinus nigra) woodland, riverine forests and some sub-Mediterranean elements, were used only sporadically, indicating high and sustained availability of wood resources in the oak forests. Anthropogenic impacts were gradual, a pattern that matches contemporary studies elsewhere in the region.  相似文献   

12.
This paper focuses on the impact of Norse settlement on vegetation and landscape around the head of Tunulliarfik (Eriksfjord) in southern Greenland. Pollen, radiocarbon, microscopic charcoal and fungal spore data are presented from a peat monolith which was collected close to the ruins of a large Norse farm complex (group ?39 at Qinngua in the former Eastern Settlement). Landnám is identified at ca. cal. a.d. 1020 by a small decrease in pollen from Betula, a slight increase in Poaceae, and the appearance of pollen from Norse apophytes (native plants favoured and spread by human activity) and anthropochores (not native and unintentionally introduced by people). Increases in microscopic charcoal and palynological richness are also apparent. This pattern is broadly consistent with that seen in other pollen diagrams from this region. The sequence is unusual for Greenland, however, in that relatively high Betula pollen percentages (average 20% TLP) are recorded throughout the period of settlement, up to the end of the 14th century a.d. before the profile becomes truncated. If these data are primarily representative of the dry land vegetation, then they suggest that birch woodland and scrub may well have persisted close to the farm throughout the Norse period. Given the potential resource value of woodland to the settlers, this may imply that birch was being managed sustainably, as was the case in Iceland during the medieval period. Coprophilous fungal spores typically found on animal dung are abundant during the early phase of settlement, yet subsequently decline in abundance. This may indicate a likely decrease in grazing intensity or livestock numbers over time, possibly in response to climatic deterioration and/or soil erosion that is expected to have placed increased stress on the pastoral farming system.  相似文献   

13.
The pollen and charcoal record of a 1,500-cm-long lake sediment core from Lagoa Nova allows a reconstruction of vegetation, climate and fire history in the Atlantic lowland of southeastern Brazil. Today the potential vegetation of the study region would be dense and tall semi-deciduous forest, related to a dry season of 4 months and 1,250 mm precipitation per year. The lowermost core section of Lagoa Nova is probably of late Glacial age and contains only few, poorly preserved pollen grains, indicating dry environmental conditions. Pollen preservation was good above 1,005-cm core depth. Extrapolating from four radiocarbon dates, this interval represents about the last 10,000 years. During the early Holocene (until about 8,500 b.p.), the landscape was dominated by savanna of the campo cerrado type (open shrub woodland), with frequent trees of Curatella americana and small areas of gallery forests along the drainage system. Savanna fires, probably natural, were frequent at that time. The palaeovegetation pattern is consistent with a long dry season of about 6 months and annual precipitation lower than today. Then, up to about 7,560 b.p., gallery forests expanded in the valleys, reflecting a shorter dry season of about 5 months and somewhat higher annual rainfall. Fire was less frequent during this wetter period. Between about 7,560 and 6,060 b.p., savanna expanded and gallery forests retreated, indicating a return to drier climatic conditions of probably between 5 and 6 months dry season and lower precipitation. Fire was again frequent, but not as frequent as during the early Holocene. During the mid to late Holocene period between about 6,060 and 2,180 b.p., the valleys were covered by semi-deciduous forest, but on the hills cerrado vegetation continued to grow. The dry season was probably around 5 months and rainfall was higher than in the preceding period. During the following period between about 2,810 and 600 b.p., the open cerrado on the hills changed to closed cerrado, reflecting wetter conditions with a shorter dry season than in the previous period. It was only after about 600 b.p. that dense semi-deciduous forests expanded throughout the study region, indicating the start of modern, wet climatic conditions with an annual dry season of about 4 months. Fire was nearly absent during this period. The reconstructed palaeoenvironment from the Lagoa Nova record is similar to that of Lago do Pires, indicating that changes in past vegetation, climate and fire frequency are regionally consistent in southeastern Brazil.  相似文献   

14.
The palynostratigraphy of two sediment cores from Soppensee, Central Switzerland (596 m asl) was correlated with nine regional pollen assemblage zones defined for the Swiss Plateau. This biostratigraphy shows that the sedimentary record of Soppensee includes the last 15 000 years, i.e. the entire Late-glacial and Holocene environmental history. The vegetation history of the Soppensee catchment was inferred by pollen and plant-macrofossil analyses on three different cores taken in the deepest part of the lake basin (27 m). On the basis of a high-resolution varve and calibrated radiocarbonchronology it was possible to estimate pollen accumulation rates, which together with the pollen percentage data, formed the basis for the interpretation of the past vegetation dynamics. The basal sediment dates back to the last glacial. After reforestation with juniper and birch at ca. 12 700 B.P., the vegetation changed at around 12 000 B.P. to a pine-birch woodland and at the onset of the Holocene to a mixed deciduous forest. At ca. 7000 B.P., fir expanded and dominated the vegetation with beech becoming predominant at ca. 50014C-years later until sometime during the Iron Age. Large-scale deforestation, especially during the Middle Ages, altered the vegetation cover drastically. During the Late-glacial period two distinct regressive phases in vegetation development are demonstrated, namely, the Aegelsee oscillation (equivalent to the Older Dryas biozone) and the Younger Dryas biozone. No unambiguous evidence for Holocene climatic change was detected at Soppensee. Human presence is indicated by early cereal pollen and distinct pulses of forest clearance as a result of human activity can be observed from the Neolithic period onwards.  相似文献   

15.
The Late Glacial to early Holocene river valley landscape of the middle Lahntal in Hessen, central-west Germany, is reconstructed by means of pollen and macrofossil analyses. AMS 14C dating combined with pollen, macrofossil and geomorphological mapping provide a detailed chronology of the floodplain sediments of the river Lahn. Archaeological evidence for early Mesolithic settlements in the middle Lahntal is backed up by pollen and macrofossil evidence, which indicates an increase in light demanding plants, together with ones indicating nutrient-rich and disturbed environments and more macroscopic charcoal and charred pieces of pine. Different phases of human impact were dated; a first phase was dated at ca. 9,270 uncal b.p. and a second phase at ca. 9,120 uncal b.p. Comparison of the palynological data from different fluvial channel fills demonstrates that during this second phase, between ca. 9,120–8,700 uncal b.p., there were several cycles of woodland clearance. The outcome of combined archaeological, palynological and macrofossil data is discussed in terms of the impact of early Mesolithic people using fire on the vegetation during the early Holocene in the middle Lahntal.  相似文献   

16.
Brandwijk-Kerkhof (ca. 4600 to 3630 cal b.c.) is a Neolithic site, located on a river dune in the Dutch Rhine/Maas river area. The natural vegetation and human impact upon it have been investigated by analysis of pollen and macroremains from four cores that are located at increasing distances up to 20 m from the site. The relationship between the strength of human impact on the vegetation and the distance of the cores from the river dune has been investigated as well. The results show that the natural vegetation on top of the river dune consisted of deciduous woodland, while in the surrounding wetlands alder carr and eutrophic marsh vegetation dominated. Human impact of limited strength resulted in more open and disturbed vegetation. There is no correlation between the strength of the evidence of human impact in the pollen diagrams and the distance of the cores from the river dune. The evidence for presence of crop plants from the cores is compared with evidence from the excavation. The first presence of crop plants from ca. 4200 b.c. onwards corresponds with data from other Dutch wetland sites. Large-scale local crop cultivation cannot however be demonstrated. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

17.
A pollen diagram from a site in the Esbjerg area, western Denmark, is used for reconstruction of the Holocene vegetational and environmental history there. During the Atlantic there was a parallel development of the landscape to that of other areas in Jylland (Jutland). From the late Neolithic onwards the development took its own course related to the approaching North Sea, which periodically inundated parts of the Esbjerg area. The record reflects landscape development in a formerly marine valley where sediments seem to be missing from parts of the Bronze Age and the early Iron Age. Consequently the landscape development during these times is only reflected in glimpses in the vegetation record, which shows gradually more open woodland and increasing human impact. During the late part of the Iron Age, Viking period and Middle Ages, the woodland was diverse in taxa but became increasingly open, finally reaching a stage during which there may have been too little wood even for daily use. At the same time the use of the land intensified. During the Sub-Atlantic, the Esbjerg area offered good natural resources with extensive grazing areas in the marine marshes in addition to good possibilities for farming and use of the woodland on higher ground, but devastating floods occurred.  相似文献   

18.
Abstract

A multi-proxy palaeoenvironmental study (pollen, non-pollen palynomorphs-NPP, macrocharcoal particles) of a small fen located in the Perafita valley (2240 m a.s.l, eastern Pyrenees, Andorra) was undertaken to trace prehistoric human activities related to woodland clearance and past land-uses at high altitudes. The results of this study constrained by 9 AMS radiocarbon measurements are combined with archaeological data and compared with similar research carried out at the same altitude in the adjacent Madriu valley (Andorra). The overall objectives of this article are, first, to formulate different chronological patterns and spatial land-use distribution at a micro-regional scale during prehistory and, second, to discuss different drivers of prehistoric occupation models in the eastern Pyrenean highlands. The palaeoecological study of the Planells de Perafita fen was performed at high temporal resolution, allowing us to focus on detailed prehistoric (mainly Mesolithic and Neolithic) and Bronze Age human activity. It demonstrates that the shaping of this cultural landscape is the result of a long-term land-use history, which began at the late Mesolithic/early Neolithic transition onwards (ca 6400–6100 cal BC). The existence of three main phases of “inter-valley” land-use variability has also been highlighted, thus testifying a complex and heterogeneous upland land-use model during the Neolithic and Bronze Age. These land-use variabilities between the two adjacent Andorran valleys provide the basis for a discussion of the way in which environmental constraints influenced prehistoric land-use spatial organisation and of how the interaction between environmental (including climatic parameters), socio-economic and cultural conditions affected the temporal and spatial dynamics of landscape shaping in the eastern Pyrenean highlands.  相似文献   

19.
A summary pollen diagram and old cartographic materials were used to reconstruct the recent vegetation history and trends of temporal dynamics of the North Adriatic Karst grasslands. Before the Roman period some evidence about grassland vegetation exists from Neolithic settlements, but deforestation, detectable on the landscape level because of pollen, started 2500-2000 years BP. A large-scale anthropogenically-driven process of clearance started in the Roman period as is reflected in the increasing pollen of grasses (Poaceae) and other herbaceous species (Apiaceae). The presence of pioneer trees (Quercus, Ostrya), juniper and grasses during 1000-400 years BP suggests that cycling processes of cultivation (strong grazing pressure), abandonment and re-cultivation were present. A 250-year-old map shows a peak of probable deforestation, where grasslands have 3.2 times larger surface area than on a recent land-use map in a 665.8 km2 large pilot area. More than 60% of grasslands changed into forest since then. On a sub-plot area of 626 ha (1% of the pilot area), where habitat mappings were performed, only 12.8% were still grasslands without tall herb invasions or scrub encroachments. Another 27.1% were grasslands with early signs of reforestation. The traditionally open landscape of the North Adriatic Karst was able to recover to forest due to almost total abandonment and sufficient mesic climate conditions.  相似文献   

20.
A high-resolution pollen record for the Holocene has been obtained from Derragh Bog, a small raised mire located on a peninsula in Lough Kinale-Derragh Lough, in Central Ireland as part of the Discovery Programme (Ireland) Lake Settlements Project. The data are compared with two lower resolution diagrams, one obtained from Derragh Lough and one from adjacent to a crannog in Lough Kinale. The general trends of vegetation change are similar and indicate that landscape-scale clearance did not occur until the Medieval period (ca. a.d. 800–900). There are, however, significant differences between the diagrams due primarily to core location and taphonomy, including pollen source area. Only the pollen profile from Derragh Bog reveals an unusually well represented multi-phase primary decline in Ulmus ca. 3500–3100 b.c. (4800–475014C b.p.) which is associated with the first arable farming in the area. The pollen diagram indicates a rapid, and almost complete, clearance of a stand of Ulmus with some Quercus on the Derragh peninsula, arable cultivation in the clearing and then abandonment by mobile/shifting late Neolithic farmers. Subsequently there are a number of clearance phases which allow the colonisation of the area by Fraxinus and are probably associated with pastoral activity. The pollen sequence from adjacent to a crannog in Lough Kinale shows clear evidence of the construction and use of the crannog for the storage of crops (Hordeum and Avena) whereas the Derragh Bog diagram and the diagram from Derragh Lough reflect the growth of the mire. This study reveals that in this landscape the record from a small mire shows changes in prehistoric vegetation caused by human agriculture that are not detectable in the lake sequences. Although in part this is due to the higher temporal resolution and more consistent and complete chronology for the mire, the most important factor is the closer proximity of the raised mire sequence to the dry land. However, the pollen sequence from adjacent to a crannog does provide detailed evidence of the construction and function of the site. It is concluded that in order to ascertain a complete picture of vegetation changes in a lowland shallow lake-dominated landscape, cores from both the lake and surrounding small mires should be analysed.  相似文献   

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