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1.
The Setesdal valley in South Norway runs north to south for 200 km, from alpine vegetation at 1200 m, passing the tree-line at around 1000 m, through Boreal forests, to Nemoral forest at sea level. The Holocene vegetation history and its altitudinal differentiation were reconstructed using pollen percentages and influx and plant macrofossil concentration records from four lakes along an altitudinal transect. During the early Holocene (c. 10500–8000 cal b.p.) Betula pubescens, Pinus sylvestris, Alnus, and Corylus expanded in the lowlands. Only Pinus and B. pubescens reached 1000 m asl (Lille Kjelavatn). Only B. pubescens reached Holebudalen (1144 m asl) at about the same time as it arrived in the lowlands. Between c. 8000–3000 cal b.p. mixed deciduous forest developed around Dalane (40 m asl) and to a lesser extent around Grostjørna (180 m asl), birch woodland with pine surrounded Lille Kjelavatn and birch woodland occurred at Holebudalen. From c. 3000 cal b.p. to present, the vegetation at Dalane hardly changed except for slight human impact and the immigration of Picea abies. At Grostjørna Pinus expanded. At Lille Kjelavatn Pinus disappeared and Betula became sparse as at the tree-line today. Betula retreated from Holebudalen thus leaving it above the tree-line in low-alpine vegetation. The strengths and weaknesses of pollen and plant macrofossil data were assessed for forest reconstructions. Where local pollen production is low, as near the tree-line, percentages of long-distance tree pollen can be misleadingly high. Pollen influxes of Betula and Pinus were much smaller near their altitudinal limits than at lower altitudes, although their macrofossils were equally abundant. The limited dispersal capacity of macrofossils documents the local presence of species and the character of the local vegetation, although macrofossils of some tree taxa are rarely found. Pollen and plant macrofossil evidence complement each other to provide a more complete reconstruction of Holocene tree-limits and tree-lines and hence climate changes, than either form of evidence alone.  相似文献   

2.
A palaeoecological investigation of a sediment core obtained from an artificial lake — the fishpond Vajgar (40 ha) near the town of Jind?ich?v Hradec, southern Bohemia, has been carried out in connection with extensive multidisciplinary research preceding the removal of its sediment. Samples from selected standard profile were subjected to chemical, pollen, and palaeoalgological analyses in order to study the chronology of vegetation development, anthropogenic impact on the landscape, and the development of an artificial fishpond ecosystem. The palaeoecological record under study comprises the period of extensive change from pre-cultural, silver fir-dominated forest vegetation into managed, agricultural landscape dominated by cereal fields and pastures. After Medieval colonization, the proportion between wooded and open landscape changed, and the composition of original forests shifted to pine. Pollen spectra from the High Middle Ages are characterized by high percentages of anthropogenic indicators and closely resemble the results from urban deposits (cesspits, wells, communication horizons, etc.). This period can be subdivided into a first phase correlated with the High and Late Middle Ages and a second phase correlated with the post Medieval period and partly maybe also with the agricultural collectivization of the 20th century. The earlier phase has a rather uniform character with a significant presence of grazing indicators and cereal weeds. After the collectivization of the 1950s and later, a substantial change in agricultural practices can be detected: the large-scale use of herbicides affecting the composition of agricultural ruderal species (e.g. decline of cornflower (Centaurea cyanus), rye (Secale), etc.). The development of the aquatic system of the fishpond Vajgar was studied by means of chemical and palaeoalgological analyses. On the basis of observed changes in the composition of subfossil algal communities, the fishpond history can be split into four distinct phases. It is assumed that the progression over individual phases was caused by changes in water chemistry that can be interpreted as shifts in water quality caused by the urbanization of the surrounding areas as well as by changes in agricultural practices. The results of the investigation of some chemical elements (especially heavy metals) show stratigraphic patterns that can be related to historical events. These results show that the mixing and bioturbation of the sediment was not so significant as might be expected.  相似文献   

3.
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   

4.
5.
Abstract

The article aims at presenting some aspects of environmental reconstruction through pollen analysis from archaeological contexts. The anthropogenic pollen transport into archaeological sites is regarded as an interesting tool to improve knowledge on flora and vegetation in the area of influence of sites. The zoophilous plants can be found more easily than in the regional airborne pollen rain where anemophilous pollen is generally overrepresented. Moreover, pollen from archaeological contexts is mainly a result of the cultural landscape shaped by human activities. Two case studies from the Bradano Valley (Basilicata, southern Italy), rich in archaeological sites dating altogether from the Middle Bronze Age to the Medieval age, are reported. Difesa San Biagio and its surroundings is one of the biggest settlements of the area, settled in early times by Enotrians. Altojanni is an extended area mainly frequented in Hellenistic, Roman late Imperial and Medieval times. A very open landscape, and clear signs of plant exploitation and cultivation, breeding and settlements were present in the two sites. Though samples are disturbed and preservation problems are sometimes observed, the main characters of pollen spectra are recurrent. High percentages of Poaceae and Cichorioideae, together with coprophilous fungal spores, strongly suggest a long tradition of pastoral activities. These case study examples suggest that human activities would have produced a fairly xeric environment.  相似文献   

6.
In the 12th and 13th centuries, the land which is now the Czech Republic underwent deep social and landscape changes, defined by historians and archaeologists as a transitional period between the early and late medieval periods. This study aims to analyze this transition as reflected by 142 pollen spectra from urban deposits so far excavated in the city of Prague. Multivariate statistics and critical assessment of the results has brought general conclusions on the potential of pollen analysis for urban archaeological research. They reveal an early medieval urban environment as a fine mosaic formed by extensive management, and composed of many habitats without sharp borders between them. Since human impact increased with time and the use of land became more rationalized and intensive, this mosaic developed a relatively coarser structure in the high medieval period. Our results support findings of the earlier subjective and uncertain characteristics of two differing types of medieval pollen spectra (Cerealia-dominated ones with low pollen diversity versus those with a higher proportion of arboreal and wild herbal pollen and high pollen diversity) obtained from various archaeological sites.  相似文献   

7.
At a Slavic site Pohansko near B?eclav (Czech Republic), at the burial ground around the church (9th–10th century) 757 skeletons (208 males, 159 females, 354 sub-adults and 36 undetermined individuals), were excavated. More or less complete vertebral column was preserved in 109 adults. Among those, in the grave number 403, the skeletal remains of an adult male were found with the deformity of the spine probably caused by severe trauma (spondyloptosis). Due to the poor preservation of the caudal part of the spine, we cannot exclude diagnoses including spondylitis tuberculosa and developmental defects of the spine such as the persistence of neurocentral synchondroses, or the retrosomatic cleft. Considering the first possible diagnosis to be the most probable, it would be the first survived case of spondyloptosis identified in the palaeopathological literature.  相似文献   

8.
The stone fortification of Prague Old Town was constructed shortly after A.D. 1230. Large-scale archaeological and archaeobotanical research has been carried out in this area in recent years. The deep moat and the drainage ditch have been excavated at several places in front of a line of former ramparts. During the initial period of their existence, the moat and the ditch contained only minimal waste. A sudden change in the management of these features occurred at the beginning of the 14th cent., when they started to be filled with large amounts of rubbish. This article concentrates on the evaluation of these rubbish strata at three profiles through the drainage ditch and one profile through the dry moat. The results of plant macro-remains (including wood), pollen, and diatom analyses clearly demonstrate the development of the local (aquatic) environment from being relatively clean to highly polluted. An actualistic (phytosociological) approach was adopted to reconstruct the local environment of the town periphery in detail, and to distinguish a variety of habitats that were situated in the economic hinterland of the city. Some species from the rich assemblages of plant remains are interpreted in terms of their use in High Medieval households. Diatom analysis completes the picture by providing the proxy data on water quality history in the drainage ditch. Received September 15, 2001 / Accepted May 21, 2002  相似文献   

9.
10.
Petr Dolej? 《ZooKeys》2015,(510):5-14
The centipede collection in the National Museum in Prague contains type material of 16 taxa (14 species and two subspecies), of which 15 were described by Luděk J. Dobroruka and one by Karl W. Verhoeff: Allothereua wilsonae Dobroruka, 1979; Chinobius alenae Dobroruka, 1980; Lithobius corrigendus Dobroruka, 1988; Lithobius creticus Dobroruka, 1977; Lithobius erythrocephalus mohelensis Dobroruka, 1959; Lithobius evae Dobroruka, 1958; Lithobius magurensis Dobroruka, 1971; Lithobius purkynei Dobroruka, 1957; Lithobius tatricus Dobroruka, 1958; Lithobius tatricus monounguis Dobroruka, 1958; Monotarsobius homolaci Dobroruka, 1971; Monotarsobius krali Dobroruka, 1979; Pachymerium dilottiae Dobroruka, 1976; Pachymerium hanzaki Dobroruka, 1976; Scolopendra aztecorum Verhoeff, 1934 and Strigamia olympica Dobroruka, 1977. Of these 16 taxa, five were described from the Czech Republic, three from Slovakia and eight from other countries (Greece, Iraq, Kyrgyzstan, Mexico, Nepal, Russia and Uzbekistan). The eight taxa described from the Czech and Slovak Republics are now considered as junior synonyms but the eight taxa described from the other countries are still valid.  相似文献   

11.
Abstract: Nautiloids of the superfamily Rutoceratoidea from the late Emsian (late Early Devonian) of the Prague Basin (Czech Republic) are commented upon. Species recognized include the hercoceratids Hercoceras mirum, H.? transiens, Ptenoceras proximum, P. nudum, P. minusculum and Anomaloceras anomalum, as well as the rutoceratids Adelphoceras bohemicum, Homoadelphoceras devonicans, Pseudorutoceras bolli and Goldringia? devonicans. In addition, four new species are described: Parauloceras regulare sp. nov., Roussanoffoceras chlupaci sp. nov., Otomaroceras sp. nov. and Goldringia sp. nov. Morphology and distribution patterns of Pragian and late Emsian rutoceratoid faunas from the Prague Basin are compared. They show that an increased diversity was accompanied by a higher level of specialization of rutoceratoids, which manifested itself in low abundance, increased facies dependence and greater variation in shell size during the Early Devonian. The evolution of sculpture and a contracted aperture, both regarded as protective adaptive features, was also examined, but no adaptive trend towards more pronounced sculpture and constriction of the aperture was found to have occurred in the Early Devonian. A more distinctive sculpture was, however, observed in shallow‐water assemblages of P. proximum in comparison with deeper‐water faunules, and two additional cephalopod species were examined in order to obtain comparative data. The presence of distinct sculpture patterns in coeval shallow‐ and deeper‐water assemblages suggests limited migration between them and consequently reflects some degree of territoriality in Devonian nautiloids. New data on early shell development in P. proximum are presented. During the Chote? Event, rutoceratoid generic diversity dropped dramatically, one family became extinct and the Early Devonian diversification of the group came to an end. The recovery of nautiloid faunas was slower than that of other cephalopods and associated, unrelated invertebrates. The absence of change in abundance patterns between Pragian and late Emsian rutoceratoid faunas, i.e. prior to and subsequent to ammonoid radiation, suggests that the appearance and radiation of the latter group in the early Emsian did not affect the structure of nautiloid assemblages, i.e. these two clades did not occupy the same niches.  相似文献   

12.
The Mokrá-Western Quarry exhibits the rare occurrence of Early Miocene (MN 4) vertebrate fauna within the area of the eastern part of Central Europe. In addition to a rich fauna of reptiles and mammals, two fossiliferous karst joints (Mokrá-Western Quarry, 1/2001 Turtle Joint and Mokrá-Western Quarry, 2/2003 Reptile Joint) yielded a rich fauna of amphibians including 13 amphibian taxa: Salamandridae: Mioproteus sp., Chelotriton sp., type I, Chelotriton sp., type II, Triturus aff. roehrsi, Triturus cf. marmoratus, Triturus sp. (T. cristatus species group), Chioglossa meini, Mertensiella mera, Salamandridae gen. and sp. indet.; Pelobatidae: Pelobates sanchizi; Ranidae: Rana sp. (synklepton Rana esculenta); Bufonidae: Bufo sp. The first records of the West European species Triturus cf. marmoratus and Chioglossa meini are reported from the eastern part of Central Europe indicating the wide distribution of those taxa throughout the whole of Europe as early as MN 4. The oldest known record of Pelobates sanchizi documents the Early Miocene presence of representatives closely related to the extinct Late Oligocene representatives of Pelobates. The slow evolution of amphibian species is documented by the presence of Triturus cf. marmoratus and the oldest known occurrence of the extinct salamander Mertensiella mera.  相似文献   

13.
This paper summarizes the results of investigations carried out in the Mokrá quarry since 2006 on the biostratigraphy of the Tournaisian-Visean (T-V) boundary interval. It also integrates previous results obtained by J. Kalvoda and collaborators. The main focus is on the boundary itself, but stratigraphically lower and higher levels have been investigated as well to provide a biostratigraphical context spanning the late Tournaisian to early Visean. This stratigraphical level has been the focus of intense international research in the recent years under the auspices of the Subcommission on Carboniferous Stratigraphy (SCCS) in order to find a new criterion and reference section (Global Stratotype Section and Point, GSSP) for the base of the Visean Stage. The appearance of Eoparastaffella simplex from its ancestor E.ovalis” and the Pengchong section (Guangxi, southern China) have recently been proposed by the Task Group on the Tournaisian-Visean Boundary and ratified by the SCCS as the new biostratigraphic criterion and GSSP for the base of the Visean, respectively. The sequence exposed in Mokrá is not suitable as a GSSP, notably because it is an active quarry, but it contains most of the foraminifer and conodont guides allowing a high-resolution biostratigraphy of the boundary interval. In addition, it contains abundant trilobites. For these reasons, it constitutes one of the best sections across the T-V boundary in Europe and can serve as a useful additional reference.  相似文献   

14.
15.
The Early Miocene vegetation of western Styria, Austria, is reconstructed on the basis of detailed investigations of leaves and diaspores from the mining area Oberdorf N Voitsberg. In this paper, the flora and probable vegetation are compared with other assemblages of similar age from the Czech Republic and Germany to elucidate the diversity of wetland and mesophytic plant communities. The floristic composition and the vegetational units represented in Oberdorf are compared to the middle part of the Most Formation (M Most Fm), Cypris Shale, Mydlovary Formation (Mydlovary Fm) of Bohemia, and the Wackersdorf mining area of Bavaria. Among these sites, Oberdorf is extremely poor in hydrophytes and reed-like monocotyledons, indicating rare pond-like habitats as well as possibly more closed swamp forest conditions than, e.g. in the M Most Fm. In Oberdorf, relatively high pH-values in the lignite-forming swamps and the possible scarcity of acidic, nutrient-poor (sandy) soils have probably influenced the floristic composition of the azonal communities. The peat-forming associations in all regions share the abundance of Glyptostrobus europaeus. However, distinct differences in the accompanying elements, such as Taxodium dubium (present and abundant only in the M Most Fm) indicate even stronger floristic variability of Early(/Middle) Miocene peat-forming and riparian plant communities than previously expected. The virtual absence of Pinus, Engelhardia, Comptonia, and probably also of Quercus kubinyii/Quercus drymeja in the megafossil record of Oberdorf can possibly be explained by the edaphic conditions. The abundance of Sequoia abietina (absent in all the other compared sites), which we assign to riparian (and mesophytic) forests in Oberdorf, may have been favoured by rich alluvial soils.In the mesophytic associations, thermophilous elements of the Lauraceae, Mastixiaceae, Symplocaceae, and Rutaceae are diverse. Usually they include Trigonobalanopsis rhamnoides/Trigonobalanopsis exacantha, an evergreen Fagaceae. This assemblage type corresponds with the Younger Mastixioid Flora sensu Mai. The Younger Mastixioid Flora is best developed in Wackersdorf, less distinct in Oberdorf, and likely in the Cypris Shale and Mydlovary Fm. It is not traceable in the M Most Fm.  相似文献   

16.
《Comptes Rendus Palevol》2018,17(8):536-544
An articulated skeleton of a morid cod (Gadiformes, Moridae) is described from the Oligocene Menilitic Formation, exposed in the Kelč-Strážné locality (Moravia; Subsilesian Unit; Western Carpathians). The fossil, preserved in dorsal view, is only partially complete, and lacking most of the postcranial part of the body. It shows a suite of features that clearly separate it from other gadiform taxa frequently found in the Oligocene-Miocene deposits of the region, and suggest its attribution to the family Moridae (mainly due to the general architecture of the skull). Due to the incompleteness of the fossil, it is not possible to define precisely its taxonomic status. However, the possession of two pterotic processes suggests that the fossil documented herein represents a member of the “Pseudophycis Group” (according to Paulin, 1989), related to the genus Lotella Kaup, 1858.  相似文献   

17.
Two genera and four species of discosauriscids, Discosauriscus potamites, D. pulcherrimus, Letoverpeton austriacum and L. moravicum , have previously been described from the Boskovice Furrow in Moravia. These laxa were differentiated primarily on the basis of proportional differences of the skull together with other morphological characters.
Excavations at two localities in the Boskovice Furrow have produced new, relatively abundant, skeletal material. The specimens are preserved three-dimensionally. In order to evaluate the differences in skull proportions, 17 variable characters on 70 skulls were measured. Statistical analysis demonstrates the existence of several morphological trends in the shape of the skull. However, no trend permits the division of this set of specimens into two clearly differentiated groups. The morphological differences used previously to define genera and species seem to be incorrect. Pending the discovery of distinct morphological differences, the Moravian discosauriscids can be considered as belonging to only one taxon: Discosauriscus austriacus (Makowsky, 1876).  相似文献   

18.
Within the countries of the former socialist bloc, the changes in the politico-economic system at the end of the 1990s created a situation where it was (and still is) necessary to restore agricultural land resource property rights, to adjust the structure of agricultural land to current needs and to improve the current state of environmental resources. This case study covers 19 cadastral areas in the western part of the Czech Republic that were affected by the land consolidation process during 2000–2006. The main task of this study was to document how land consolidation processes could affect the change of land use and landscape structure and whether the land consolidation planners take into account the protection of natural resources. The increased acreage of grasslands was the most important change which has occurred in the land use in the 19 analysed cadastral areas, before and after land consolidations. In the studied area, the changes of land use involved 6.8 % of the total land consolidation area. This area of grassland significantly increased the protection of agricultural land from water erosion. In terms of changes in the landscape structure, the construction of new field road networks is the most important result. The results confirm the importance of land consolidation processes not only for the organization and recovery of ownership and cadastral records but also for the improvement of agricultural use of landscape and protection of natural resources such as soil, water and plant and animal communities.  相似文献   

19.
Makupa creek is connected to the Indian Ocean via the Killindini creek; the study deals with the distribution of heavy metals in the Makupa and Killindini creeks.Concentrations of Cu, Cd, Fe and Zn, in sediments at the inner sections of the creeks were high compared to those measured at Likoni (ocean). Considering trace metal levels at the inner sections relative to Likoni the ratios obtained, were Cd 7:1, Cu 13:1, Fe 5:1 and Zn 21:1.The results obtained point at Makupa creek as the main source of heavy metals into the creek system, however iron behaved differently, it was significantly higher at the Killindini Habour P<0.05 (at 95% confidence level).There was a decline in concentrations of, copper and zinc from the inner stations to the frontwater zone at Makupa creek. Spatial variations of cadmium were not significant between inner and frontwater zones of the Makupa creek P>0.05 (at 95% confidence level), and also between Makupa and Harbour. There was however a significant difference P<0.05 (at 95% confidence level) between Likoni and Makupa.  相似文献   

20.
Results of thermoluminescence (TL) dating of 11 heated flint artifacts from the 2002 excavation at Brno-Bohunice, Czech Republic, are presented. The samples are from the eponym locality for the Bohunician, an industrial type considered technologically transitional between Middle and Upper Paleolithic core reduction strategies. The Bohunician is the first early Upper Paleolithic technocomplex in the Middle Danube of Central Europe and, therefore, is implicated in several issues related to the origins of modern humans in Europe. The Bohunician provides an example of how one technological strategy combines crested blade initiation of a core with the surficial (almost Levalloisian) reduction of blanks as blades and points. As the Middle Danube lacks antecedents of the behavioral steps within this technology, several hypotheses of inter-regional cultural transmission, with and without hominin gene flow, could explain the appearance of the Bohunician. The elucidation of the temporal context of Bohunician assemblages is, therefore, a critical step in understanding the behavioral, and potentially biological, succession in this region. Radiocarbon age estimates from charcoal associated with Bohunician sites suggest a wide age range between 33 and 41 ka 14C BP, which is also observed for individual sites. TL dating of heated flint artifacts provides ages on the calendric time scale of an archeological event, the firing. The weighted mean of 48.2 ± 1.9 ka BPTL for 11 heated flint samples from Brno-Bohunice provides the first non-radiocarbon data on archeological material from the Bohunician. The TL dating, in conjunction with the archeological and sedimentological analysis, allows the evaluation of the integrity of this new type-collection. The hypothetical possibility of the incorporation of Szeletian artifacts (i.e., leaf points) into the site formation processes can therefore be refuted.  相似文献   

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