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1
Content available remote Późnoglacjalny rozwój osuwisk w polskich Karpatach zewnętrznych
EN
The area of Poland, including the Carpathian Mountains, is located in a zone where landslides cause large material damage. This issue can be considered using different time scales. Using various dating methods, it was possible to distinguish periods of increased landslide activity. Among others, the radiometric methods are the most common. Based on the 14C dated landslides in Szczawnica-Biafy Stream, Zapadle near Szymbark, Rychwatd near Żywiec and on data published by Margielewski (2006), it was possible to hypothesize that landslides in the Carpathians have been developing over 13,000 years, i.e. since the Oldest Dryas. This is related to the beginning of degradation of the permafrost, which can be considered as the inception of the development of large rock landslides. On the basis of the presented data, it can also be stated that these landslides have been active up to modern times and their development is very long. An example of this is the landslide in Zapadle. The position of the landslide tongue, which is subjected to erosion, is of great importance, which promotes its further activity. Permanent removing of the colluvial material by a stream and its supplementing by subsequent new displacements from the scarp causes that the landslides can be active for a very long period of time.
EN
The paper presents the results of the first OSL dating of glaciofluvial and ice-marginal lake sediments which occur between end moraines of the Słupsk Bank and the Polish coast. The sand and gravel of glaciofluvial deltas on the Słupsk Bank were deposited most likely during a period from 14.3 ±1.2 to 16.6 ±1.4 ka ago. The deposition of silty-sandy sediments of the ice-marginal lake is dated at 14.51 ±0.81 and 14.6 ±1.4 ka years. Likewise, dates ranging from 13.74 ±0.84 to 16.70 ±1.1 ka obtained from low sandy ridges, related to the southern range of the ice-marginal lake in the Gardno-Łeba Lowland, indicate the most likely timing of their deposition. It can be concluded that a short stop of the ice sheet on the Słupsk Bank took place approximately 15.2 ka ago, which could be correlated with the position of the ice sheet front in central Skáne and in northern Lithuania at that time. Older and younger results were also obtained, except the dates mentioned above. The older ages show little sunlight exposure of sediments during their deposition. The younger dates indicate a marine origin of the sediments and show that some parts of glaciofluvial sediments were redeposited and exposed to sunlight at a later stage, most probably when dead-ice blocks were melting.
EN
Climate fluctuations and related crucial environmental changes in the Late Glacial and Holocene in the southern Baltic Sea area can be reconstructed by mollusc analyses. Lacustrine sediments host an association of molluscs and other fossils, including freshwater species such as: Armiger crista f. cristatus, Gyraulus laevis, Lymnaea peregra, Pisidium casertanum, Pisidium casertanum f. ponderosa, Pisidium milium, Pisidium nitidum, Pisidium obtusale f. lapponicum, Valvata cristata and Pisidium conventus, which indicate cold climate. Deposition in freshwater reservoirs continued during the Early Holocene. at that time, species characteristic of cold freshwater environments were accompanied by freshwater mollusc species that require higher temperatures: Bithynia tentaculata, Physa fontinalis and Pisidium amnicum. This suggests climate warming in the Preboreal period. These lacustrine sediments were partly destroyed and covered by marine sands during the Middle and Late Holocene. Good indicators of changing environmental conditions from freshwater to marine are the following marine species found in the sediments: Hydrobia ulvae, Hydrobia ventrosa, Cerastoderma glaucum, Mytilus edulis and Macoma balthica.
PL
Zmiany klimatyczne, a za tym daleko idące zmiany środowiska w późnym glacjale i holocenie na obszarze południowego Bałtyku mogą być wyjaśniane także przez badania fauny mięczaków. Na obszarze południowego Bałtyku w okresie późnego glacjału występowały gatunki słodkowodne wskazujące na klimat zimny, takie jak: Armiger crista f. cristatus, Gyraulus laevis, Lymnaea peregra, Pisidium casertanum, Pisidium casertanum f. ponderosa, Pisidium milium, Pisidium nitidum, Pisidium obtusale f. lapponicum, Valvata cristata, Pisidium conventus. Akumulacja jeziorna w słodkowodnych zbiornikach strefy przybrzeżnej kontynuowała się w okresie wczesnego holocenu. W tym czasie oprócz gatunków słodkowodnych, zimnolubnych pojawiły się gatunki mięczaków i małżoraczków słodkowodnych, o wyższych wymogach termicznych (Bithynia tentaculata, Physa fontinalis, Pisidium amnicum). Świadczy to o ociepleniu się klimatu w okresie preborealnym. Zrastanie przybrzeżnych zbiorników rozpoczęło się w okresie borealnym i trwało również w okresie atlantyckim. W tym czasie miały miejsce wlewy wód morskich do zbiorników. Wskaźnikiem tego jest liczne występowanie morskich gatunków takich jak: Hydrobia ulvae, Hydrobia ventrosa, Cerastoderma glaucum, Mytilus edulis, Macoma balthica. W osadach piaszczystych w okresie subborealnym i subatlantyckim zdecydowanie przeważała fauna morska.
EN
Lacustrine organic sediments were sampled at Gronowo (Chełmno Plateau) and Piotrkowo (Dobrzyń Plateau) located within a widespread system of subglacial channels separated by the large Drwęca ice-marginal valley. They have been examined for their pollen, plant macro-remains and geochemistry, as well as radiocarbon-dated. The analyses have allowed reconstructing the evolution of the area and presenting an asynchronous appearance of two lakes. Before lake sedimentation, glaciolimnic sediments from the end of Plenivistulian, at the site of Piotrkowo, was dated. Lacustrine sedimentation started during the Allerød at Gronowo, and during the Preboreal at Piotrkowo. The different age of the two lakes is ascribed mainly to differences in the Late Glacial drainage conditions which directly affected the melting away of dead-ice blocks buried in the channels.
EN
The climate changes and related crucial environmental changes in the Late Glacial and Holocene in the Southern Baltic area can be investigated by mollusc and ostracod analyses. It is well known that accumulation of mineral and biogenic sediments in the Southern Baltic area began in the Late Glacial. The process took place in cold tundra lakes and mires. The presence of lake basins is confirmed by seismoacoustic investigations and the resulting 3D spatial model. Lacustrine sediments contain an assemblage of molluscs and ostracod fauna represented by freshwater species indicating cold climate, such as: Armiger crista f. cristatus, Gyraulus laevis, Lymnaea peregra, Pisidium casertanum, Pisidium casertanum f. ponderosa, Pisidium milium, Pisidium nitidum, Pisidium obtusale f. lapponicum, Valvata cristata, Pisidium conventus, Candona candida, Candona neglecta, Cytherissa lacustris, Darwinula stevensoni and Cypridopsis vidua. The accumulation in freshwater reservoirs was continued during the Early Holocene. Besides cold freshwater species, sediments of that age also contain freshwater species of molluscs and ostracods that required higher temperature: Bithynia tentaculata, Physa fontinalis, Pisidium amnicum, Candona compressa and Metacypris cordata. It indicates a climate warming in the Preboreal period. These lake sediments were partly destroyed and covered by marine sands during the Middle and Upper Holocene. Good indicators of changing from a freshwater to marine environment are the following marine species found in the sediments: Hydrobia ulvae, Hydrobia ventrosa, Cerastoderma glaucum, Mytilus edulis, Macoma balthica, Cyprideis torosa and Cytheromorpha fuscata.
EN
The main phases of the Late Glacial and Holocene development of vegetation in the Wigry National Park were reconstructed based on the pollen analysis of sediments from three small dystrophic lakes (Lake Suchar Wielki, Lake Suchar II and Lake Slepe). At the current stage of research, the age of the studied deposits was determined by AMS radiocarbon dating of few samples only. This meant that the chronology of the investigated profiles had to be estimated also indirectly using their palynological correlation with a radiometrically well-dated profile from Lake Wigry. The obtained pollen data confirmed the picture of the postglacial vegetation changes of the Wigry National Park, which was based on earlier studies of Lake Wigry. Furthermore, it documented the existence, mainly in the Preboreal and Atlantic chronozones, of temporary changes in vegetation, which might be a reaction to a short-lived cold fluctuations of climate.
EN
Late Glacial and Holocene carbonate lacustrine deposits developed as lacustrine chalk and calcareous gyttja are fairly widespread across northern Poland. They form fillings of palaeolakes which developed during the deglaciation. These formations are usually covered by peat. Rich and diversified malacofauna has been found in the aforementioned sediments. The profiles from 154 sites described and published by various authors were subjected to malacological analysis. In the whole material, 18 molluscan assemblages were distinguished, representing three types of habitats: terrestrial, of temporary water bodies, and of permanent water bodies. The composition and structure of these assemblages allows characterizing climate and differentiating habitats. The time-sequences of malacological assemblages provided possibility to define three types of malacological sequences. On the basis of these successions, a scheme of the lake water bodies evolution during Late Glacial and in northern Poland was elaborated.
EN
In the field seasons of 1990 to 2008 the Combined Prehistoric Expedition conducted an extensive archaeological, archaeozoological, archaeobotanical and geomorphological field work at more than a hundred sites in the Nabta, Kiseiba, El Kortain, Gebal El Beid, Gebel Ramlah and Berget El Sheb Areas, South Western Desert of Egypt. The research has helped to develop a long chronological sequence of Late Glacial and Holocene climatic changes in the region. The climatic sequence has been supported by more than 300 14C and OSL assays that permitted to place most of the climatic events in a firm chronological frame.
EN
The paper presents the history of diatom studies carried out in the Gulf of Gdańsk and the Vistula Lagoon since the beginning of the 20th century. One aspect of the research focuses on describing the structure of planktonic and benthic communities living in different parts of the area or occurring in their surface sediments as taphocoenoses. Other investigations concentrate on the fossil diatom flora, which is widely used in the research on the Late Glacial and Holocene to resolve paleogeographic, sedimentological and paleoecological problems.
EN
This study provides a vegetation and climate history of an alpine wetland in the centre of China’s Qinghai–Tibetan Plateau (QTP) over the last 14.8 ka. High resolution climate proxies include vegetation (pollen), geochemical (Ba, Rb, δ13C) and physical (particle size and magnetic susceptibility) data; optically stimulated luminescence (OSL) and AMS radiocarbon dating were used to reconstruct the environmental changes in the wetland ecosystem. Based on physical and geochemical proxies, the sucession divided into five stratigraphic units encompassing time intervals of 14.76–14.31, 14.31–13.17, 13.17–4.47, 4.47–0.51 and 0.51–0 ka. The average sedimentation rate of all these units was 0.098 mm/a. The study showed that this ecosystem was sensitive to climate change.
11
Content available remote Progress in the Holocene chrono-climatostratigraphy of Polish territory
EN
The Holocene delivers a unique possibility to establish climatic stratigraphic boundaries based on detailed chronostratigraphy reflected in various facies of continental sediments, in their lith-ological parameters and organic remains. These sediments are dated by the 14C method in the case of organic remains, by counting annual laminations in lacustrine facies, and by dendrochronological method in the case of fluvial sediments. The existence of well dated profiles enables to reconstruct various climatic parameters like ampli-tudes of seasonal temperatures, types and frequency of extreme rainfalls and floods and, finally, to distinguish rare rapid changes and most frequent gradual ones. This reconstruction is based on the analogous effects of various types of present-day rainfalls. The current authors present a critical review of existing chronostratigraphic divisions starting from simple millennial division by Mangerud based on Scandinavian palynological stratigraphy of peat-bogs and Starkel's concept based on fluctuations in rainfall and runoff regime reflected in fluvial and other facies of continental deposits. In the last decades, the calibration of 14C dates allowed a new approach to be used for the construction of the probability distribution function of these dates in various facies or types of sediments, which formed a background for distinguishing and correlating climatic phases and defining boundaries be-tween them. These approaches have been creating new opportunities for revision of the existing chronostratigraphy. The aim of this paper is to present a revised version of chronostratigraphic division based on climatic fluctuations reflected in various facies of sediments on the territory of Poland and discuss their corre-lation with other European regions and global climatic changes.
EN
High resotution studtes on subfossil Cladocera from three closely located lakes of the Chełm Hills Region - Lake Słone, Syczyńskie, and Pniówno, evidenced a strong zooplankton response to the well-known climatic changes of the Late-Glacial and early-Holocene. The general changes in the cladoceran community structure resemble those described from other Polish and European lakes. Certain important differences were identified, however, which can be attributed to the peculiarity of the environmental conditions of the region, regarding: the deep character of the lakes studied already in the initial phase of their development (Older Dryas), an intensive eutrophication process induced by the Allerӧd climate warming with a periodical lowering of the trophic status, and the character of the Younger Dryas coollng less severe than in some other regions. The chronology of the palaeoenvironmental changes identified by means of subfossil Cladocera analysis was based on the results of palaeobotanical analysis, and confirmed by radiocarbon dating available for two profiles. Taking advantage of the close location of the study sites, their morphometric and geological similarities, and the high resolution of sampling, an attempt was made to use cladoceran succession in order to establish the stratigraphic division for Lake Pniówno, lacking palynological and radiocarbon data.
13
EN
Accelerator mass spectrometry (AMS) 14
EN
Vegetation changes in the Lower San Valley near Jarosław are reconstructed from the Younger Dryas to the present time on the basis of palynological analysis of the peat core. The pollen profile came from a an old riverbed and was supplemented by radiocarbon datings. The Younger Dryas and early Preboreal vegetation was characterised by a high proportion of forest communities with pine (Pinus sylvestris and P. cembra) and birch (Betula), while patches of open area were dominated by the steppe with Artemisia. Climatic amelioration during the Preboreal chronozone led to the rapid spread of elm (Ulmus), which was probably a dominant taxon on the lowest terraces of the valley. Terrestrialization of the water body existing in the palaeomeaner and the subsequent beginning of peat accumulation caused a deterioration in pollen preservation. Hence, the interpretation of the profile section spanning the period between the Boreal and Subatlantic chronozones was seriously disturbed due to selective corrosion and the overrepresentation of Pinus sylvestris type and Filicales monolete sporomorphs. Between ca. 336 and 1152 AD fluctuations in woodland cover were recorded. Important components in those forests, despite the domination of Pinus sylvestris, were Quercus, Carpinus betulus, Fagus sylvatica and Abies alba. The first pollen grains of cereals (Cerealia type) were found before ca. 1605-1414 BC and may be attributed to the agricultural activity of the Neolithic and/or early Bronze tribes. Periods of strong deforestation caused by humans were probably related to the time when the Tarnobrzeska Group of the Lusatian Culture and the Przeworska Culture were active. The first groups of Slavs did not significantly influence the environment, but the subsequent development of those groups led to more visible deforestation, which was triggered after the establishment of Jarosław in the 11th century AD.
EN
Accumulation of sediments in the lake basins of the Starogard Lakeland, Northern Poland, an area which was entirely ice-covered during the last glaciation, started at different times, beginning during the Late Glacial. Sedimentation continued till the beginning of the Holocene (Preboreal). The principal factor causing the asynchronous start of the lake development was the variation in melting processes of buried dead-ice blocks. The preservation of dead-ice masses in some depressions until the Preboreal leads to the conclusion that the ultimate disappearance of permafrost in the study area occurred only at the beginning of the Holocene.
PL
Na torfowisku Taboły (Puszcza Knyszyńska) wykonano łącznie 20 odwiertów, charakteryzujących jego budowę geologiczną. W analizowanym materiale biogenicznym rozpoznano szczątki wegetatywne i generatywne 94 taksonów roślinnych. Rozwój torfowiska rozpoczął się w starszym dryasie, kiedy to zatorfienie zostało zainicjowane przez zbiorowisko Scorpidium scorpioides. Na przełomie allerod/młodszy dryas rozwinął się zbiornik wodny, którego zanik przypadł na przełom późnego glacjału i holocenu. W okresie preoborealnym na torfowisku dominowały zbiorowiska mchów brunatnych z udziałem brzóz krzewiastych oraz szuwary wielkoturzycowe. Od schyłku okresu subborealnego postępowała oligotrofizacja siedlisk, co doprowadziło do przekształcenia się złóża w torfowisko przejściowe. Spadek poziomu wód gruntowych znalazł odzwierciedlenie w podwyższonym stopniu rozkładu torfu, w najmłodszej fazie rozwoju torfowiska. Tempo akumulacji torfu było wówczas najmniejsze.
EN
In Taboły mire (the Puszcza Knyszyńska Forest) 20 drillings were made altogether. Vegetative and generative remains of 94 plant taxa were recognized. According to radiocarbon dating, the mire started to develop in the Late Glacial period. In the Preboreal period brown moss communities with and admixture of shrub birches and sedge rushes dominated in the mire. At the end of the Subboreal period habitat oligotrophication proceeded which resulted in the transformation of deposits into transitional bog. Groundwater decline was reflected in a higher intensity of peat decomposition. The rate of peat accumulation was then the lowest.
EN
The investigation area is situated in the north part of Mazurian Lakeland in NE from Węgorzewo in the borderland between Poland and Russia. It was covered with the ice sheet during the upper stage of the Vistulian Glaciation. During the recession of the maximum range of the ice-sheet (Pomeranian Phases) the 6 ice-sheet retreated were left. Skaliska Basin this is end depression, between two end moraine zones. The glaciolacustrine and lacustrine sediments was recorded late glacial and postglacial history. The results of the multidisciplinary investigations including cartographical, sedymentological methods indicate that in the ice-dammed lake in Skaliska Basin was existed in front of the ice. The outflow from Skaliska ice-dammed was connected with the ice sheet retreat (behind the Pregoła Valley) and development of the new erosion base level (like Pregoła Valley).
PL
Analizie malakologicznej poddano skorupki ślimaków i małży występujące w gytiach wapiennych i kredach jeziornych wypełniających torfowisko Gajlik na Pojezierzu Sejneńskim. W sześciu analizowanych próbkach stwierdzono występowanie 13 gatunków mięczaków wodnych. Obserwowane zmiany składu i struktury zespołu mięczaków uzupełnione wynikami analiz palinologicznych i radiometrycznych pozwoliły na rekonstrukcję ewolucji torfowiska Gajlik w okresie późnego glacjału i dolnego holocenu. Skorupki mięczaków występowały wyłącznie w osadach związanych z cieplejszym i okresami (interfaza alleröd oraz preborealna i borealna faza holocenu). Nie pojawiały się one natomiast w osadach zimnych okresów późnego glacjału.
EN
Malacological analysis was conducted on snails and bivalve shells present in calcareous gytia and lacustrine chalk of the Gajlik mire in the Sejny Lake District. Thirteen species of water molluscs were identified within six analyzed samples. Changes observed in the structure and composition of molluscs, supplemented by palynological data, and the results of radiocarbon datings allowed for the reconstruction of the mire's evolution during Late Glacial and Early Holocene period. Molluscs' shells occurred solely in sediments associated with warmer periods (interphase Alleröd and Preboreal-Boreal phases of Holocene). Additionally, they were not present in sediments associated with cold Late Glacial periods.
19
Content available remote Malacostratigraphy of Late Glacial and Holocene in Poland
EN
Assemblages of molluscs have been used for stratigraphy of Late Glacial and Holocene deposits in Poland. Changes of the climate as well as migration of species are main factors which control the recompositions of molluscan communities in this time. Thirteen malacostratigraphical zones have been definied. Eight of them corresponds with land environments, while the remaining ones (five) with water habitats. The succesions of these zones gives the malacostratigraphical subdivisions, which can be compared with similar schemes proposed in some other countries of Central Europe. They supplement palynostratigraphical zones or even can be used as main way of stratigraphical intrepretations.
20
Content available remote History of the Białowieża Primeval Forest, NE Poland
EN
Białowieża in Poland is a very famous region in Europe (because of its primeval forest and bison population), but its environmental history is poorly known. This article shows the results of palynological analysis, macrofossil analysis and geological settings of two mires in the Białowieża Forest. The pollen diagrams show changes of the vegetation cover from the younger part of the Late Glacial until the present time. The relative time scale is based on palynostratigraphy and comparison to published results of other sites from the adjacent regions. During the Late Glacial two stages of the vegetation succession were revealed: steppe and forest during the Alleröd period and tundra-like vegetation during the Younger Dryas. The Holocene history consists of five stages of plant cover development. The special features of the Białowieża Forest are conditioned by two main factors: low degree of anthropogenic impact and influences of continental climate and boreal zone, stronger than in the other regions of Poland.
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