Search

Wasted tires are the great source of fuel and valuable components but could be a cause of environmental and land pollution. This study shows the detailed method for the determination of radiocarbon isotope (14C) concentration in tires and their pyrolysis products. Samples are taken from truck and passenger car tires in the form of shredded rubber, pyrolysis oil and recovered carbon black. Liquid scintillation counting (LSC) and accelerator mass spectrometry (AMS) techniques were used for the investigation at Gliwice Radiocarbon and Mass Spectrometry Laboratory, and National Laboratory for Age Determination, Trondheim, Norway. The results are in good agreement. Radiocarbon concentration of the rubber varies significantly because of its complex structure and composition within the tires. The 14C concentration values were found to be higher in pyrolytic oil compared to rubber, and greater in truck tires rather than car tires.

Terrestrial environments tend to be characterized by an incomplete record of past conditions. For the MIS 3–2 periods, there is only one known site in Poland—Horoszki Duże—in which a probably continuous record of climate change has been preserved. However, this site does not have any high precision multi-proxy analyses. In the absence of continuous high-resolution records, we decided to gather and analyze scattered information. We assembled data originating from various sites in Poland and checked whether the available results of 14C and luminescence dating presented in the form of probability density distributions (PDF) and kernel density estimation (KDE) models would allow their reinterpretation. The data were compared to the Greenland isotope curve to see whether they were consistent with the hypothesis that the number of “warming-cooling” cycles recorded in the examined sediments was of the same order as in those ice-core records. Previously in Poland, usually only two interstadial periods (i.e., Hengelo and Denekamp, 36–38.6 and 28–32 14C kBP, respectively) have been identified in the discussed period. The joint analysis of data from a larger area revealed more warming-cooling events than recorded from individual sites.

During the last 60 years, the thickness of the Grel peatland deposits (Polish Inner Carpathians), was decreased twice: from about 7.4 m in 1962, to 3.9 m in 2019. Pollen analyses of peat deposits performed in 1962 (Koperowa 1962) and 2019 (this study) showed that the peatland deposits have accumulated since the Oldest Dryas Stadial up to the present day. Comparative analysis of both palynological profiles was carried out, which exhibits a high consistency of the percentage of pollen of several taxa for the 10 horizons occurring in both profiles. Based on the age–depth curve made for the new profile, the modeled age for the above-mentioned compliance levels was obtained and based on this age, a “retrospective” age–depth model was elaborated for the Koperowa’s profile. The analysis of both profiles showed that the compaction of sediments did not occur proportionally in the entire sequence. The conducted research indicates that contemporary human activity may significantly affect the whole length of peatland profiles, not only their upper parts, as previously was considered. The reconstruction of the palaeoenvironment (palaeoclimate) based on multiproxy analysis of the peatland deposits is capable to precisely document this phenomenon.

Subfossil trunks of pine (Pinus sylvestris L.) from the Late Weichselian were discovered in the site Koźmin in the Koło Basin, central Poland (Dzieduszyńska et al., 2014a). Another part of organic sediments with trunks was excavated in the frame of the research project. Altogether 224 samples from Koźmin were analysed dendrochronologically; they represented generally young trees, 40 to 70 years old. Based on the most convergent sequences, the chronology 2KOL_A1 was produced, 210 years in length. With the wiggle-matching method, it was dated to ca. 13065–12855 cal BP. Dendrochronological dating of trunks buried in organic sediments, most of which occurred in situ, revealed that tree deaths occurred successively, over more than 100 years. That could have been due to unfavourable climatic conditions, as well as extreme events, e.g. strong winds.

The Somes fluvial fan is located in the NW extremity of the Great Hungarian Plain (Pannonian Basin). It was formed by the left-side tributaries of the Tisa River (a tributary of the Danube) as they developed westward, following the avulsion of the main Tisa channel. Drainage reorganisation after the avulsion has occurred via a complex interplay between tectonic, climatic and autogenic controls over the past similar to 50-30 ka. In this study, we discuss the role of these factors in the spatial and temporal dynamics of the fluvial system that constructed the Somes fluvial fan during the second half of the last glacial cycle, using a combination of cartographic, sedimentary, and chronological tools. Our data suggests that, within a general setting of subsidence, spatial and temporal variation in the rate of this subsidence between different tectonic blocks created four local base levels, while autogenic factors play only a secondary role. The modern drainage configuration results from spatial channel adjustments during the last ca. 3000 cal BP, related to the current subsidence centre located in the NW extremity of the Somes fluvial fan. Over the entire period analysed, the rivers draining across the fluvial fan predominantly meandered, except when the river switched to a braided pattern. This braided phase likely occurred before similar to 30-32 ka ago, apparently coeval with a similar short, braided phase that has been documented along the middle Tisa River. The braiding phase is coincident with intense deglaciation in the Somes catchment area and development of open forest vegetation at lower elevations. Climatic changes during and after the Last Glacial Maximum had a reduced impact on the style of fluvial flow, which returned to a meandering pattern. Ca. 5000 cal BP these changes impacted suspended sediment delivery to drainage networks resulting in the present-day channel dimensions, at least along their lower reaches (our study area). Our results highlight the lower sensitivity of rivers draining the Great Hungarian Plain to the Late Quaternary climate changes compared to the far more responsive rivers of Western European. This behaviour is, in our opinion, most likely due to the presence of glacial forest refugia in the catchment areas, which modulated the response of discharge and fluvial dynamics to climatic changes.

An analysis was performed on samples from a series of well-preserved tree trunks and in situ stumps of Allerod/Younger Dryas age found in Koźmin and Kwiatkow, Kolska Basin, Central Poland. Five different types of wood preparation methods were investigated in three Polish radiocarbon laboratories (Gliwice, Poznan and Krakow) in order to find the most stable, repeatable and reliable procedure. Their effect was tested on the stable carbon isotope ratio (δ13C) and 14C age. Additionally, FTIR spectroscopy was used as a simple technique for obtaining rapid information on the structure of wood constituents and chemical changes taking place in wood due to various chemical treatments. The results of AMS measurements did not show statistically significant differences in radiocarbon ages of samples prepared according to the tested methods. On the other hand, δ13C measurements showed that the smallest scattering results gave α-cellulose obtained by the method BABA + Bleaching (with NaClO2 and HCl) + strong base. Moreover, the mean δ13C values for holo-cellulose samples are higher than those for α-cellulose samples. Studies evidenced that the methods of preparation leading to holo- or α-cellulose gave the same FTIR spectra, while the standard method of the chemical pretreatment of samples for 14C measurements (ABA) preceded by mercerization is insufficient for removing compounds containing aromatic rings.

Our project aimed to construct a Scots Pine (Pinus sylvestris L.) chronology for part of the Late Glacial and reconstruct changes in the 14C concentrations during this period. Kwiatków (Kolska Basin, central Poland) proved to be very prospective site, in which wood from the end of Allerød was recognized. A level of organic deposits with so-called fossil forest was encountered within the late-Vistulian terrace of the low valley of the Warta river. Dendrochronological analysis of over 267 samples complying to the requirements of the method allowed, at the present stage of the research, to construct a chronology spanning 265 yr. Fifty-two samples (5 consecutive rings each) were subjected to α-cellulose extraction and 14C measurements. Ninety-six results and the wiggle-matching technique anchor the chronology to the period 13,821–13,561 cal BP (Acomb=141.6%) according to the D_Sequence procedure and the IntCal13 calibration curve or to 13,800–13,540 cal BP according to the wiggle-matching technique using the χ2 test and raw data, i.e. the Heidelberg tree-ring sequence.

About 70% of the last cold stage was taken by transitional phases of continuous fluctuations of climate and permafrost extension. All this is reflected especially well in slope types and the thickness of slope, fluvial and aeolian deposits. Very distinct and relatively fast changes took place around 33–30 ka BP: the aridification of climate with an ice sheet transgression, expansion of continuous permafrost and the onset of loess deposition. The greatest transformations of slopes and river valleys in the Carpathians and Subcarpathian Basins took place not in the coolest phases but during the Interpleniglacial. The authors exemplified a number of sites in Southern Poland documenting frequent fluctuations of climate and permafrost from that 25–30 ka long period. Calibrated dates of dated episodes correlate well with the δ18O curve from Greenland with frequent warmings. These rapid warmings are reflected in the higher rate of aggradation in valley floors and thick colluvial material deposited over slopes, both combined with a retreat of permafrost. The comparison with the Greenland 18O curve is valuable to establish a comparable chronology of events, even for such a distant area like Central-Eastern Europe.

We reconstructed 3300 years (3500 BCE and 200 BCE) of the development history of the Rąbien peatland located in central Poland, using pollen, macrofossil, testate amoebae, Cladocera, Chironomidae and geochemistry. Central Europe, particularly Poland, is characterised by a transitional climate that is influenced by continental and Atlantic air masses, which makes this region very sensitive to climate change. Our results demonstrate the high potential of the Rąbien peat record to reconstruct palaeohydrological dynamics. The studied time interval is characterised by two pronounced dry periods: from ~ 2500 to ~ 1700 BCE and from ~ 700 to ~ 500 BCE, and two significant increases in the water table: from ~ 1000 to ~ 800 BCE and from ~ 500 to ~ 250 BCE. The timing of the wet shift at 600 BCE corresponds to wet periods at different sites in Central and Eastern Europe. Our investigation reveals a more complicated and complex than previously assumed set of climatic relationships in Europe between 3500 BCE and 200 BCE, which might be linked through complex teleconnections of atmospheric circulation patterns. Only reconstructions that are based on an understanding of current observations from peatlands and lake ecosystems may lead to a better interpretation of past climate changes.

The fluvial landforms of the last cold stage are represented in the Sub-Carpathian Basins by a system of 2–3 terraces, which grade into alluvial fans of a height of 15–20, 8–12 and 6–8 m above the present riverbeds in the mountain foreland. In the Vistula River valley the 15–20 m high terrace, covered with loess, extends along the western margin of the Sandomierz Basin and northern margin of the Carpathians. Away from the mountain margin, it passes into the sandy terrace plain with dunes. It is formed of at least two Interpleniglacial alluvial fills: the older one dated at 48–36 ka BP (over 50–40.6 ka cal BP) and the younger one dated 30–25 ka BP (34.1–29.0 ka cal BP) thus pertaining to the Upper Pleniglacial. This latter forms a terrace 15 m high. In general, accumulation of fluvial sediments interrupted with erosion phases dominated in the mountain foreland during the period 60–25 ka BP (over 60–29 ka cal BP). The most significant erosion phase took place before the maximum extension of the Vistulian (Weichselian, Wisconsinian) ice sheet (i.e. before 25–20 ka BP = 29–24 ka cal BP) and was connected with a change from an oceanic to a more continental climate. The next alluvial fill of terrace 8–12 m high (with remnants of braided river channels) was formed at the end of the Upper Plenivistulian. The incision of the river channels below the present channel level was followed by aggradation in the Late Vistulian (15–13 ka BP = 18.2–15.6 ka cal BP) accompanied by a change in river channel system from braided to meandering. In the Wisloka and San River valleys alluvial plains extending by lateral erosion of large meanders were abandoned by rivers mainly in the Younger Dryas and the Preboreal. The Late Vistulian large palaeomeanders are missing along lower Sola and lower Dunajec. These rivers, fed from higher mountains, had still tendency to braiding. The climate cooling of the Younger Dryas brought an increase in the delivery of bedload to the river channels and a tendency to braiding in Vistula valley (Drwinka depression). The expansion of forest in the Early Holocene reduced the water discharge and the size of meanders. As a result, their width fallen by 3–5 times. Alluvial data showed also a distinct humid climatic phase ca. 9.5–8.5 ka cal BP.

High-resolution biological proxies (pollen, macrofossils, Cladocera and diatoms), geochemical data (μ-XRF element scans, TOC, C/N ratios, δ 18 O carb and δ 13 C org values) and a robust chronology based on varve counting, AMS 14 C dating and tephrochronology were applied to reconstruct lake system responses to rapid climatic and environmental changes of the Trzechowskie palaeolake (TRZ; Northern Poland) during the late Allerod – Younger Dryas (YD) transition. Palaeoecological and geochemical data at 5–15 years temporal resolution allowed tracing the dynamics of short-term shifts of the ecosystem triggered by abrupt climate change. The robust age control together with the high-resolution sampling allowed the detection of leads and lags between different proxies to the climate shift at the Allerod-Younger Dryas transition. Our results indicate (1) a water level decrease and an increase in wind activities during the late Allerod and the Allerod-YD transition, which caused intensified erosion in the catchment, (2) a two-decades delayed vegetation response in comparison to the lake depositional system. Comparison with the Lake Meerfelder Maar record revealed slightly different vegetation responses of the Trzechowskie palaeolake at the YD onset.

An age-depth model based on radiocarbon dates was produced from a Holocene profile collected from a rich fen situated in the Beskid Sądecki Mountains (the Outer Western Carpathians, southern Poland). The model is compared against the results of palynological and loss on ignition (LOI) analyses supplemented by the identification of organic deposits. Five distinct palynological episodes are detected. These potential palynological age markers are critically compared with the results of age-depth modeling and other dated profiles. The results presented distinctly show that using palynological episodes as age markers for age-depth construction may be highly misleading. DOI: 10.2458/azu_js_rc.55.16308

A simplified model of hydrological changes during the Late Glacial and Holocene is presented for the northern Polish regions that were ice covered during the Last Glacial. This reconstruction is based on a group of 197 radiocarbon dates from about 120 localities reflecting the sequence of alternating lake transgressions and regressions. The earliest transgressions were related to dead-ice melting (sometimes in 2–3 phases), while the later ones started during more humid phases. However, these were usually followed by regressions, which may have been connected with the formation of new drainage systems and with the overgrowing of shallow lakes by peat bogs. DOI: 10.2458/azu_js_rc.55.16343

The Holocene delivers a unique possibility to establish climatic stratigraphic boundaries based on detailed chronostratigraphy reflected in various facies of continental sediments, in their lithological 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 amplitudes 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 between 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 correlation with other European regions and global climatic changes.

The central part of Europe during the last cold stage was occupied by permafrost and twice invaded by the Scandinavian ice sheet, but about 70% of time was taken by transitional phases of continuous fluctuations of permafrost, which are reflected especially in type and thickness of slope, fluvial and aeolian deposits

In this study, we test the possibility of using databases of radiocarbon ages to estimate boundaries of climatic chronozones. The Alaska region was chosen and compared with chronozones of 2 European countries: Poland and the Netherlands. The study included setting up a database of14C ages published for climatic records from Alaska. Some 97414C determinations on organic samples were selected and used to establish chronozones for the Late Glacial and the Holocene for the Alaska region. The selected data were calibrated and a summed probability density function (PDF) was calculated. The shape analysis of the constructed frequency distribution of14C dates on calendar timescales together with the assumption about preferential sampling seems to be a useful tool for establishing calendar ages for boundaries of climatic periods, i.e. chronozones.

Archaeological excavations at the Syrian settlement of Tell Qaramel have been conducted since 1999. They are concentrated on remnants of the Protoneolithic and early stages of the Pre-Pottery Neolithic period. The settlement has revealed an extremely rich collection of everyday use of flint, bone, and mostly stone objects, such as decorated chlorite or limestone vessels; shaft straighteners used to stretch wooden arrow shafts, richly decorated in geometrical, zoomorphic, and anthropomorphic patterns; as well as different kinds of stones, querns, mortars, pestles, grinders, polishing plates, celts, and adzes.Excavations brought the discovery of 5 circular towers. Some 57 charcoal samples were collected during the excavations and dated in the GADAM Centre in Gliwice, Poland. The stratigraphy of the settlement and results of radiocarbon dating testify that these are the oldest such constructions in the world, older than the famous and unique tower in Jericho. They confirm that the Neolithic culture was formed simultaneously in many regions of the Near East, creating a farming culture and establishing settlements with mud and stone architecture and creating the first stages of a proto-urban being.

Carbonate binders from mortars and plasters as well as charcoal fragments sampled at the ancient settlement of Hippos (Sussita) have been subjected to radiocarbon dating by gas proportional counting (GPC) and accelerator mass spectrometry (AMS). Hippos is situated on the east coast of the Sea of Galilee (32°46′N, 35°39′E) at the top of a hill in the Golan Heights area, Israel. According to historical-archaeological data, the town had functioned since the 3rd century BC until AD 749, when it eventually crumbled into ruins after an earthquake. The appropriate sample selection and preparation based on the results of petrographic observations permitted us to distinguish different phases involved in the expansion of the settlement. More than 200 samples were taken from the settlement and subjected to petrographic and chemical analyses. Of the 200 total samples, about 20 were selected for dating. Here, we present the first 10 results of 14C dating carried out for Hippos. The oldest sample dated thus far gave an age corresponding with the 2nd century BC to 1st century AD—probably indicating an old Roman temple, on the base of which the North-West church (NWC) was later erected. The next dates extend up to the 8th century AD, the age related to the last phase of settlement inhabitation. Research is continuing as new excavations take place.

In general, the evolution of fluvial systems in Central-Eastern Europe reflects the main phases of climatic changes during the period of 60–8 ka cal BP registered in Greenland ice cores and their isotopic 18 O curves. The Greenland isotope curve shows many more wiggles and stages than the fluvial record of the same time, especially during the Interpleniglacial phase. In Central-Eastern Europe, we observe several deviations from those climatic trends, connected with different factors, among which are the long distance of the region from the Atlantic Ocean and an increase in continentality. At times, this region was occupied by permafrost although the coexisting warm summers during a part of the studied period enabled the presence of a forest cover. These factors together controlled the specific features of the fluvial regime and sediment load reflected in alternating trends to erosion or aggradation and from meandering to braiding. The permafrost influenced snowmelt floods and tendency to braiding. The dense vegetation (with trees) reduced the supply of sediments and stabilized the meandering channels. Very distinct changes occurred in the river valleys that drain the mountains, where ceaseless fluctuations of vegetation vertical zones were present, especially during the unstable Interpleniglacial when the supply of load from the higher vegetation zones was increased. This system, controlled by the climate and plant vegetation, was modified by other factors including tectonics, wind activity during dry periods, blocking of valleys by ice sheets, meltwater supply, and sea level fluctuations of two reservoirs.

We report on a statistical analysis of a large set of radiocarbon dates for reconstruction of paleoclimate. Probability density functions were constructed by summing the probability distributions of individual 14C dates. Our analysis was based on 2 assumptions: 1) The amount of organic matter in sediments depends on paleogeographical conditions; 2) The number of 14C-dated samples is proportional to the amount of organic matter deposited in sediments in the examined time intervals. We quantified how many dates are required to give statistically reliable results. As an example, 785 peat dates from Poland were selected. The dates encompassed the Holocene and Late Glacial period. All dates came from the Gliwice Radiocarbon Laboratory. Results were compared with other paleoenvironmental records. Detailed analysis of the frequency distributions showed that preferential sampling plays an important part in the shape determination. The general rule to take samples from locations where visible changes of sedimentation are apparent (e.g. from the top and the bottom of the peat layer) results in narrow peaks in the probability density function near the limits of the Holocene subdivision.

The Grel raised peat bog is located in the Ludźmierz village vicinity in the Orawa-Nowy Targ Basin. This raised bog, has heavily degraded peat dome covered with numerous post excavation pits which are the results of peat extraction for local purposes. Peat bog is overgrown with birch and pine forests and typical vegetation for raised bog. First palynological study of the peat depositional sequence was performed by Koperowa (1962). The beginning of the peat bog formation was then attributed to the Oldest Dryas. Consequently the Grel is the oldest peat bog in the peatland of the Orawa-Nowy Targ Basin

We applied two widely-used methods for data partitioning - constrained incremental sum-of-squares (CONISS) and Optimal Partitioning (OP) along with two supplementary methods, a Kohonen artificial neural network (self-organising map, SOM) and the indicator value (IndVal) index, for the quantitative analysis of subfossil chironomid assemblages from a palaeolake in Central Poland. The samples, taken from 79 core depths, were divided into 5-11 groups (five by SOM, seven by CONISS, 11 by OP), for which different numbers of indicator taxa were determined with the use of the IndVal index (18 for CONISS, 15 for SOM, 11 for OP). Only six indicator taxa were common to all three methods. The number of highly specific (p < 0.001) taxa was highest for SOM. Only the SOM analysis clearly reflected the rate of the changes in chironomid assemblages, which occurred rapidly in the Late Glacial (as a result of greater climate variability) and slowly in the Holocene (as a reflection of slow long-term changes in the local habitat, such as paludification). In summary, we recommend using SOM and the IndVal index in combination with CONISS and/or OP in order to detect different aspects of temporal variability in complex multivariate palaeoecological data.

Records of past climate variability and associated vegetation response exist in various regions throughout Central and Eastern Europe (CEE). To date, there has been no coherent synthesis of the existing palaeo-records. During an INTIMATE meeting (Cluj Napoca, Romania) focused on identifying CEE paleo-records, it was decided to address this gap by presenting the palaeo-community with a compilation of high-quality climatic and vegetation records for the past 60-8 kyrs. The compilation should also serve as a reference point for the use in the modelling community working towards the INTIMATE project goals, and in data-model inter-comparison studies. This paper is therefore a compilation of up to date, best available quantitative and semi-quantitative records of past climate and biotic response from CEE covering this period. It first presents the proxy and archive used. Speleothems and loess mainly provide the evidences available for the 60-20 ka interval, whereas pollen records provide the main source of information for the Lateglacial and Holocene. It then examines the temporal and spatial patterns of climate variability inferred from different proxies, the temporal and spatial magnitude of the vegetation responses inferred from pollen records and highlights differences and similarities between proxies and sub-regions and the possible mechanisms behind this variability. Finally, it identifies weakness in the proxies and archives and their geographical distribution. This exercise also provides an opportunity to reflect on the status of research in the area and to identify future critical areas and subjects of research. ispartof: Quaternary Science Reviews vol:106 pages:206-224 status: published

A comprehensive database of radiocarbon dated fluvial units in Great Britain, Poland and Spain has been compiled to investigate the relationship between environmental change, flooding and Holocene river dynamics. Following the methodology recently developed by Macklin and Lewin [Macklin, M.G., Lewin, J., 2003. River sediments, great floods and centennial-scale Holocene climate change. Journal of Quaternary Science 18, 101–105], radiocarbon dates in fluvial sequences that coincide with a modification in sedimentation rate, or style, have been highlighted, allowing geomorphologically significant changes in Holocene river activity to be identified. Data analysis has been undertaken at both national and sub-national scales, and on catchments of different size, type and land-use history. Multiple phases of higher flood frequency, characterized by accelerated erosion and sediment deposition on floodplains, are recognized and compared with a range of climate proxies. The relative and varying roles of climate and land-use on river dynamics are considered and the value of the database for reconstructing past hydrological events, as well as for predicting river response to future environmental change, is assessed., Funding for this collaborative research project was principally provided by ICSU (International Council for Science), NERC (NER/A/S/2001/00454 to Macklin and Lewin) and Historic Scotland (Macklin and Johnstone) and this support are gratefully acknowledged

Current calibration methods for single and replicate 14C dates are compared. Various forms of tabular and graphic output are discussed. Results from all the methods show reasonable agreement but further methodological development and improvements in computer output are required. Comparison of existing techniques for a series of non-contemporaneous dates showed less agreement amongst participants on this issue. We recommend that calibrated dates should be presented as a combination of graphs and ranges, in preference to mean and standard deviation.

A set of computer procedures for probabilistic calibration of 14C dates was developed at the Gliwice Radiocarbon Laboratory for the IBM PC compatible microcomputer. The program comprises three main options: 1) calibration of a single 14C date, 2) calibration of a set of arbitrary dates, 3) calibration of a set of related dates. Results of calibration are presented in the form of graphs and numeric data, including tables of selected quantiles and inter-quantile ranges of resulting probability distribution of cal age. In this paper, we present the aims of the program, with a short description of its structure, show examples of working with output data in terms of expected archaeological application, and consider the possibility of standardization of calibration procedures.

Large sets of radiocarbon dates of 1019 peat, 155 speleothem, and 100 tufa samples, as well as dates of 330 fluvial samples, were investigated in order to estimate environmental variability during the last 16,000 calendar years in Poland. All 14C dating was carried out in the Gliwice Radiocarbon Laboratory, and results are stored in the RoS database. Probability density functions (PDFs) were created by summing up (on the calendar timescale) individual age probability distributions of all dates for different types of material and for different regions of Poland. We used an updated version of the Gliwice Radiocarbon Laboratory calibration program GdCALIB. The 14C dates were calibrated using the IntCal04 calibration curve (Reimer et al. 2004), and results were compared with other paleoenvironmental records. The authors conclude that analyzing PDFs of different types of sediments can be helpful in the qualitative reconstruction of the past environment. The PDF for peat samples primarily reflects paleohydrological conditions; the PDFs for speleothem and tufa samples reflect changes in temperature and humidity, while analysis of the PDF created for fluvial data is in a general agreement with the PDFs constructed for peat samples.