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1.
Analysis of wood charcoal that was conducted as a part of an interdisciplinary project at Pyeonggeo-dong, a multi-period agricultural complex located in Jinju, South Korea, reveals oak (Quercus sp.) to be the most commonly encountered wood over the period of 4000–1500 cal. b.p. The charcoal data indicate that Quercus was one of the most abundant woody plants in the surrounding vegetation, although its dominance in the charcoal assemblage may partly represent preferential human selection in the past. The data suggest that Quercus-dominant forest declined with the growth of a secondary forest of Platycarya strobilacea around the site from about a.d. 300. This change postdates by more than a thousand years the earliest evidence of large-scale agriculture, which is visible in the form of carbonized crops and large tracts of prehistoric agricultural fields. A relatively large number of pit dwellings for the Three-Kingdoms period (ca. a.d. 300–500) at Pyeonggeo-dong suggests that this late sign of human impact on vegetation is related to the extension of agricultural fields to previously uncultivated hilly areas and/or increased needs for fuel and timber caused by high population density of the site.  相似文献   

2.
Aim To test whether fire contributed to the expansion and compositional change of evergreen forests in the Mediterranean region during the Holocene. Location The peri‐Adriatic region, encompassing the Italian peninsula, Sicily and the western and southern Balkans between latitudes 46° and 37° N. Methods New high‐resolution pollen and microscopic charcoal data from Lago dell’Accesa (Tuscany, Italy) were used to estimate the response of the evergreen oak, Quercus ilex L., to fire during its expansion phase at 8500 cal. yr bp . The data were compared with the pollen and charcoal series from other Mediterranean sites (Lago di Massaciuccoli in Tuscany, Malo Jezero in Croatia, Biviere di Gela in Sicily) and analysed using numerical techniques (redundancy analysis, detrended canonical correspondence analysis) to identify long‐term fire–vegetation linkages and the degree of compositional change. Results Microscopic charcoal and pollen of evergreen oaks were negatively correlated during the period of quasi‐natural fire regime (Mesolithic, 10,000–8000 cal. yr bp ). In addition, there was no such positive correlation during periods when the fire regime was potentially more influenced by people (Neolithic–Bronze Age, 8000–3000 cal. yr bp ). Compared with inland sites, coastal sites that are currently located at a distinct ecotone showed more compositional change. Main conclusions The analyses suggest that climatic change, without an additional effect of fire regimes, favoured the expansion and compositional change of evergreen forests across the peri‐Adriatic region. Strikingly different patterns occurred along a north–south gradient. In the north (Tuscany and Croatia, meso‐Mediterranean belt), Q. ilex replaced deciduous forests when conditions became drier; in the south (Sicily, thermo‐Mediterranean belt) the species replaced maquis or steppe vegetation when climatic conditions became moister. We conclude that the projected increase in fire activity may lead to the loss of most of the remaining relict forests of Q. ilex in southern Europe.  相似文献   

3.
The investigated area near Flintbek (Schleswig–Holstein, Northern Germany) was used as a burial ground from the Neolithic until the Iron Age. Due to modern agriculture, the above-ground funerary monuments have been destroyed. Rescue excavations from 1976 to 1996 recovered the archaeological remains. In addition to the archaeological reassessment of the findings, further scientific analyses were carried out. The results of the charcoal analyses are presented in this paper. The overall spectrum of wood species represents the typical species composition of mixed oak forests. Over the whole investigated time span (Neolithic–Iron Age) these species alternate with a second group of taxa: species benefiting from better light conditions. In times of intensive human impact, these light-demanding taxa gained considerable importance, showing the opening of the wooded landscape. In phases with less human impact, a regeneration of mixed oak forest is detectable. For the Neolithic it was possible to develop a more detailed picture of wood usage based on 162 radiocarbon dates of 106 samples. These illustrate considerable changes during the Neolithic, which resulted in a varied pattern of open land and closed forest influenced by human presence and land use. Another important aspect of the Flintbek area is the handling of samples deriving from different contexts. While charcoal samples related to fire usage or grave constructions contain only slight contamination, samples from fillings (pits, burial layers) are characterized by charcoal dating being either too old or even too young for the archaeological context.  相似文献   

4.
The remains of Olea europaea in archaeological contexts in the southern Iberian Peninsula have been found in the Epipalaeolithic levels of Cueva de Nerja (10860±160 b.p.). The abundant appearance of charcoal and some seed remains from the Copper Age (3rd millennium b.c.) in the coastal zones of the southeast indicate that this species formed part of the vegetation of the Thermo-mediterranean zone and that its fruits were collected during these periods. However, Olea did not appear in the Meso-mediterranean zone until the Roman period, when olive cultivation was introduced there. The presence of charcoal and olive stones from the 1st century a.d. onwards is abundant, together with remains of structures for oil pressing.  相似文献   

5.
Interdisciplinary studies of the sediments of Lago dell’Accesa started in 2001. We present here results from the palynological study. The pollen diagram provides a record of vegetation and climatic change spanning over 15,000 years. The oldest pollen spectra show a late-glacial steppe vegetation typical of central and southern Italy during this period. The Late-glacial Interstadial, interrupted by two cooling events, is dominated by open deciduous oak forests. The Younger Dryas is represented by 150 cm of sediment and shows the presence of steppic vegetation. The Holocene vegetation is characterised by alternating dominance of deciduous oaks and Quercus ilex. The three zones characterised by Q. ilex are accompanied by peat layers marking lake-level lowering at ca. 8600–7900, 4600–4300 and 3700–2800 cal b.p. Between approximately 9000 and 6000 cal b.p. extensive Abies-forests existed on the Colline Metallifere located 15–20 km to the north and northeast of the lake. Local fir populations may also have existed by the lake. Human impact starts at approximately 8000 cal b.p. during the Neolithic period, and increases at ca. 4300 cal b.p. Castanea and Juglans pollen is recorded from ca. 2800 cal b.p. The impact of the Etruscan settlement near the lakeshore is shown in the increasing values of arable crops, species of secondary forest canopy (Ericaceae, Pinus, Pistacia, Myrtus) and anthropogenic indicators (Chenopodiaceae, Plantago lanceolata, Rumex etc).  相似文献   

6.
Within the field of pile-dwelling research in SW Germany, the application of a dendroarchaeological approach to the study of young wood among large timber series has allowed a better understanding of the short-term development of settlement showing high variations of building activity coupled with varying strategies of timber supply and woodland use. This is illustrated by systematic tree-ring investigations at the Neolithic lake-shore site of Hornstaad-Hörnle I, which have demonstrated an occupation of 20 years around 3900 BC. On specific levels of dendrodating and on the basis of heteroconnections, short alternating building phases with specific choice of timber have been found, showing a wave-like development of the settlement. Repeated short-term repairs also give an estimation of the time spans during which the houses were in use. Furthermore, the timber supply seems to have been based principally on coppicing and the defoliation damages caused by the cyclic development of the cockchafer can be detected in the young oak series. Particularly interesting are the alternating building phases with ash (Fraxinus excelsior L.) on one side, and oak (Quercus robur L./Quercus petraea [Matt] Liebl.) and beech (Fagus sylvatica L.) on the other side. After an initial building phase with ash wood gained from the azonal vegetation, the strong development of the village was accompanied by the systematic use of timber from an oak and beech mixed stand located in the mesophile deciduous forest. In our interpretation, this alternance seems to be linked with a shifting cultivation system at the beginning of the Neolithic lake-shore site occupation at Lake Constance. Oak and beech building phases correspond to a short period of greater concentration of occupation, probably with increasing agricultural activities whereas the use of ash wood gained from the hydrophilous vegetation belt behind the village, occurred in the phases of installation or dissolution of the community. In comparison, later settlement development in the whole region shows a greater stability in the building activity as well as in the woodland use.  相似文献   

7.
Analyses were performed of plant remains from the Late Neolithic (in Slovenian terminology corresponding to Eneolithic or Copper Age, ca. 4300–2300 b.c.) pile dwelling Hočevarica in the Ljubljansko barje (Ljubljana Moor), Slovenia. This settlement existed between ca. 3650 and 3550 cal b.c. Seeds, fruits, wooden piles, macroscopic charcoal and pollen from the cultural layers were analysed. The remains of domestic plants such as charred grains of Hordeum vulgare (barley), Triticum monococcum, T. dicoccum (einkorn and emmer wheat) and Papaver somniferum (poppy seeds), as well as seeds of weeds such as Chenopodium album-type indicate early cultivation in the area. In addition, numerous remains of nuts and berries, especially of Quercus sp., Cornus mas, Rubus fruticosus and Corylus avellana demonstrate that the gathering of wild plants was an important part of subsistence. Palaeoecological and archaeobotanical data from Hočevarica further suggest that cleared land was used for agriculture and pastures during the Neolithic, and that different wood was cut for construction and for fuel. The species assemblage from Hočevarica is very similar to those recovered from northern Alpine lake dwelling sites, however, several new taxa (e.g. Lathyrus sativus, Vicia sp.) appear in the assemblage. One of the most surprising finds is the seed of wild grape (Vitis vinifera ssp. sylvestris), which are the oldest on-site remains of grapevine from Slovenia.  相似文献   

8.
The Mediterranean Basin is a global biodiversity hotspot, and oak tree species play an important role in it. Since the beginning of the Holocene (∼11.4 kyr BP), the distribution of forests has not occurred uniformly, resulting in diverse types of vegetation landscapes. In this study, we used a maximum entropy algorithm (MaxEnt) to obtain the ecological niche model (ENM) of two sub-Mediterranean oak species, Quercus pubescens Willd. (pubescent oak) and Quercus ilex subsp. ilex (holm oak), both in the present day in the Iberian Peninsula and within a Middle Holocene (8.2–4.2 kyr BP) climatic scenario in the NE Iberian Peninsula. Moreover, we used the locations of Neolithic archaeological sites containing anthracological data to analyze the relationship between human occupations and oak habitats. Our results suggest that the two oaks have responded differently to the climatic conditions that have occurred, and show changes in both potential distributions. The palaeolandscape vegetation map shows a denser vegetation cover in the lowlands and a more open landscape in the highlands, with a higher dominance of Quercus pubescens in the septentrional areas, while Quercus ilex was more restricted to certain coastal areas. Temperature and precipitation factors, mainly seasonal climatic conditions, have had a greater impact on the distribution of vegetation than other factors. We found a good overlap between the ENM of the two oaks and the locations of the Neolithic sites analysed, and determined that the distribution of Neolithic archaeological sites is not random. The Neolithic populations in the study area depended heavily on the resources of the deciduous and evergreen sub- Mediterranean forest, although they also exploited the resources of the mountain pine forest. Neolithic sites distribution suggests that Neolithic human groups were aware of the potential of forests and probably gathered woody resources in their surroundings.  相似文献   

9.
The paper presents a synthesis of the on-site archaeobotanical investigations of the Terramara di Montale, one of the most important sites of the Terramara cultural system which characterised the Po Plain in the Middle-Late Bronze Age (1650–1200 b.c.). Samples for pollen analysis and macroremains, including seed/fruit and wood/charcoal records, were collected from stratigraphic sequences and occupation levels during the excavations 1996–2001. The results permitted the reconstruction of the main characteristics of the landscape which at the onset of the Terramara rapidly passed from a natural, more forested landscape with mixed oak wood and conifers to a more open and anthropic landscape characterised by cereal fields, pastures and meadows. People felled oaks and other trees such as Populus/Salix and Fraxinus to make piles or walls for houses. Wood from these species was also recorded as charcoal in the hearths. Palynological and carpological data show that the inhabitants of the Terramara largely founded their economy on cereals (mainly Triticum aestivum/durum, T. dicoccum and Hordeum vulgare). They also grew a few legumes (Vicia faba var. minor, Vicia sp. and Lens culinaris). There was also grazing by domestic animals, mainly ovicaprines but also pigs and cattle, and these were fed exploiting wild plants such as Carpinus. In the paper the four main steps of the history of the Terramara are described (before the Terramara, the onset, the Terramara phase, the decline) during which both human influence and climatic changes were important. At the onset of the Terramara (around 1600 b.c.) a warm and possibly dry phase occurred. The intense use of the territory and a climatic deterioration at around 1300 b.c. might have triggered the decline of the Terramara di Montale.  相似文献   

10.
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   

11.
A pollen and charcoal record from Gargano (southern Italy) provides new information on the vegetation history and environmental change in southern Italy during the middle to late Holocene. The chronological framework is provided by six AMS radiocarbon dates carried out on plant macroremains. Pollen diagrams record a Mediterranean vegetation along the coastland and a stable mixed oak forest at higher elevations between ca. 5900 and 4200 cal b.p. A sharp and dramatic fall of tree pollen concentrations and a change in fire frequencies occurred from approximately 4200 cal b.p. suggesting a climate change towards drier conditions. This event is coherent with regional and extra-regional palaeoclimatic records that suggest that a mid-Holocene dry period was experienced in southern Italy, southern Spain, and perhaps further afield. Human impact on vegetation seems to have occurred since about 2700 cal b.p.  相似文献   

12.
Charcoal analysis is a useful tool to gather information about the diversity of vegetation as well as human behaviour towards the environment and the diversified management of natural plant resources. Here we present the taxonomic identification of charcoal and calculate the percentage of each diameter class of the pieces excavated from the Shannashuzha archaeological site, Gansu Province. We discuss the implications of the data for the composition of the past woodland vegetation and prehistoric human fuel collection strategy. Twenty-two taxa were identified from 2,241 charcoal fragments with a further 50 fragments unidentified. Picea, Pinus, Bambusoideae, Salix, Populus, Quercus and Betula were abundant in many samples, although Bambusoideae is probably over-represented due to its high chance of being preserved. The vegetation around the Shannashuzha site had a typical mountain character and the main vegetation types reflected by the charcoal records included conifer woods, mixed broadleaved/conifer woods and riverbank broadleaved woods. This vegetation is similar to the modern vegetation and therefore the climate at that time is deemed to have been similar to or slightly warmer than today. Abundance was probably an important factor in the fuel collection strategy of the people. Collection of wood with a small diameter was a purposeful choice by prehistoric people, probably because it was less time-consuming in the study area, which was rich in wood resources. We conclude that in this region, prehistoric people selected firewood depending not on its type, but rather on its size (diameter). Charcoal from fruit trees found at this site and at many others nearby indicates that there was a common and long history of fruit utilization by prehistoric people in the western Loess Plateau. These results provide valuable information and a new insight into the interaction between human activities and plant resources in the Neolithic period.  相似文献   

13.
Aim To investigate the effects of abrupt climate change in the North Atlantic on the vegetation history of lowland Central America. We use palynological evidence from a Central American lake on the Yucatan Peninsula to evaluate the effects of rapid climate changes during the last ice age, between 65 and 8 ka. Location Lake Petén‐Itzá, lowlands of northern Guatemala. Methods Sediment core PI‐6 was sampled at c. 170‐year resolution for pollen and charcoal analysis in order to construct a temporal sequence of environmental change. Uni‐ and multivariate statistical analyses were performed on the pollen dataset to test whether there was an association between Heinrich events in the North Atlantic and vegetation changes in the Central American lowlands. Results Pollen analysis revealed that the composition of plant assemblages on the Yucatan Peninsula varied in phase with rapid changes in North Atlantic climate. Pine savannas were the main vegetation type between c. 60 and 47 ka. These savannas gave way to pine–oak (Pinus–Quercus) forests in the latter half of the last ice age. Marked episodes of replacement of the pine–oak assemblage by xeric‐tolerant taxa occurred during Heinrich events. The Last Glacial Maximum (LGM) was characterized by mesic conditions. Main conclusions The pollen record from Lake Petén‐Itzá showed that vegetation changes associated with Heinrich events were more significant than those associated with the LGM. Each Heinrich event produced a characteristic shift towards xeric taxa. Although colder than Heinrich events, the LGM on the Yucatan Peninsula was relatively moist, and the presumed savannization of the landscape during the maximum cooling of the last glacial was not supported by our data. Our findings suggest alternative scenarios for plant diversification and genetic interchange during glacial times, and also indicate that vegetation in tropical continental settings was not as stable as previously thought.  相似文献   

14.
Questions: (i) Can sampling of soil wood charcoals at high spatial resolution produce new evidence concerning the presence of chalk grassland before or during the Neolithic, Bronze and Iron Ages? (ii) Are there correlations between vegetation history and archeological data during these periods at this particular site? Location: The chalk hillsides of Saint‐Adrien in the lower Seine Valley, Upper Normandy, northwest France. Methods: The study was carried out at a high spatial resolution in chalk grassland using soil wood charcoal analysis, in which charcoals found in the soil were identified and dated in an area of several hundred square meters. Results: Late‐successional woody species (Fagus sylvatica, Quercus sp.) were still present in the study site in an area inconsistent with the existence of large chalk grassland herbaceous plant communities (several hectares) in the Neolithic (6500–3800 BP) and Bronze Age (3800–2700 BP). Conclusions: The presence of late‐successional woody species on the studied hillside suggests that fires in the Neolithic were linked to forest clearance for pastoral activities, as already demonstrated for similar ecosystems in eastern France and Germany. Nevertheless, our methodology clearly demonstrates that palaecological studies need to take into account the spatial organisation of plant communities as a complementary element to validate their potential existence in former times.  相似文献   

15.
Analyses of pollen, macrofossils and microscopic charcoal in the sediment of a small sub-alpine lake (Karakol, Kyrgyzstan) provide new data to reconstruct the vegetation history of the Kungey Alatau spruce forest during the late-Holocene, i.e. the past 4,000 years. The pollen data suggest that Picea schrenkiana F. and M. was the dominant tree in this region from the beginning of the record. The pollen record of pronounced die-backs of the forests, along with lithostratigraphical evidence, points to possible climatic cooling (and/or drying) around 3,800 cal year b.p. and between 3,350 and 2,520 cal year b.p., with a culmination at 2,800–2,600 cal b.p., although stable climatic conditions are reported for this region for the past 3,000–4,000 years in previous studies. From 2,500 to 190 cal year b.p. high pollen values of P. schrenkiana suggest rather closed and dense forests under the environmental conditions of that time. A marked decline in spruce forests occurred with the onset of modern human activities in the region from 190 cal year b.p. These results show that the present forests are anthropogenically reduced and represent only about half of their potential natural extent. As P. schrenkiana is a species endemic to the western Tien Shan, it is most likely that its refugium was confined to this region. However, our palaeoecological record is too recent to address this hypothesis thoroughly.  相似文献   

16.
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   

17.
Charcoal piles have become a frequent subject of research in recent years as a better understanding of past human activities in forests is sought. The age of charcoal piles is usually determined by radiocarbon dating; dendrochronology is rarely used because of the small size of preserved charcoal remains and the insufficient number of visible tree rings. This paper presents the potential for dendrochronological and 14C method in research into charcoal piles. From 14 charcoal-burning sites in the Czech Republic, 214 pieces of charcoal were anatomically identified at the genus level and dendrochronologically analysed. Our results show that fir dominated in these charcoal remains, followed by oak, beech, spruce and pine. With an overall dendrochronological dating success of 24 %, fir charcoal was dated most often (65 %) with measurable tree rings ranging from 14 to 90. The oldest charcoals were dendrochronologically dated to summer 1682 CE; conversely, the youngest had end dates in the second half of the 19th century. The relatively poor dating success of oak charcoal very likely resulted from the use of branches for charcoal production rather than tree trunks. Based on an analysis of selected charcoal samples, we confirm that radiocarbon dating provided a very wide range of dates in the post-1650 CE period and the use of the wiggle-matching method was usually challenging because of short TRW series. Based on samples with preserved waney edges, we conclude that charcoal was more commonly made from wood felled in the summer than in the winter. Despite the relatively low level of success of dendrochronological dating, it seems more effective for dating charcoal than the 14C method, especially with samples from the last 350 years.  相似文献   

18.
Abstract. The natural origin of old Quercus ilex (holm oak) forests on the west coast of Corsica is a matter of dispute. This paper discusses the use of pedoanthracology, especially adapted to approach topics in palaeoecology requiring a high spatial precision. It also shows the importance of fire in vegetation change during the Holocene. Pedoanthracology relies on botanical identification and AMS 14C dating of micro-charcoal found in soil. Three test pits were dug in a forest currently protected within the ‘Man and Biosphere’ program. These pits yielded large quantities of charcoal. There is evidence that Pinus nigra ssp. laricio (laricio pine) and understorey heather species (Ericaceae) played an important role in the vegetation at the beginning of the Subatlantic (ca. 2500 BP). The importance of Pinus pinaster (maritime pine), Quercus ilex and a few mesophilic species increased between 2000 and 1000 BP. Charcoal fragments found in the soil show the role of fire in the vegetation changes recorded. The late expansion of P. pinaster results from a high fire frequency. The hypothesis proposed in the paper suggests that fires destroyed the remaining toxic humus that had accumulated during the millennia which preceded the arrival of Q. ilex to our study sites. The late development of holm oak forest is a combination of the migration of the species and the increase of fire frequency since 2500 BP, most probably resulting from slash-and-burn agriculture.  相似文献   

19.
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   

20.
Abstract. The natural Mediterranean maquis and forest vegetation of Israel is commonly considered to be composed mainly of four, roughly equal components: Pinus halepensis, deciduous oak, evergreen oak, and Ceratonia - Pistacia communities. They represent the past climax and subclimax of this region. Evidence accumulated from pollen analysis and wood remnant research in geological and archaeological excavations, as well as from written historical sources, shows that this view is wrong: the ancient vegetation in this area was dominated by Quercus calliprinos.  相似文献   

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