Search

Reconstructing the palaeodiet of populations associated with the Lusatian Urnfields is an important part of the study of prehistoric communities. It is particularly important because of the limitations arising from the widespread use of cremation in this period, which precludes the determination of carbon (δ13C) and nitrogen (δ15N) stable isotope ratios in bone collagen. The stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) were analysed in bone samples selected from the 23 individuals recovered from inhumation burials in the bi-ritual cemetery of the Lusatian Urnfields in Świbie, Gliwice District. Samples from preserved fragments of long bone shafts and cranial bones, and in one case a fragment of the last lumbar vertebra, were selected for analysis. Due to the very poor state of preservation of the skeletons, it was impossible to carry out palaeodiet reconstruction studies for many of the individuals. No animal bones with diagnostic characteristics were preserved in the Świbie cemetery, so the trophic background was determined based on the published data for fauna from Neolithic and Late Bronze Age sites. All bone samples were mechanically cleaned. The obtained samples were then subjected to the standard collagen extraction procedure used in the Radiocarbon and Mass Spectrometry Laboratory, which is based on the modified Longin method. For most of the individuals examined, some measurements of stable carbon and nitrogen isotopes were obtained despite their clear, macroscopically determined contamination with organic compounds. Most of the samples analysed showed a C/N ratio that met the quality criterion, which ranged between 2.9 and 3.6. Samples of two individuals, from graves 2 and 259, were contaminated, with subsamples for the individual from grave 2 well outside the range obtained for the others. The δ13C values ranged from -21.22‰ to -17.63‰ (X = -18.86; S.D. = 0.825), while the δ15N values ranged from 4.62‰ to 9.5‰ (X = 8.25; S.D. = 1.003), excluding the data for the contaminated samples. The sample selected for an adult of undetermined sex, from grave 2, came from a pre-WWII excavation carried out around 1936. The contamination, shown by isotopic testing, most likely came from a preservative, which was probably isinglass (fish glue). It was most likely made from the swim bladders of freshwater fish. Most of the individuals examined to establish their palaeodiet were characterised by a high trophic level, indicating a balanced diet based on food of inland origin, with C3 plants and a high proportion of food of animal origin. The individual of undetermined sex and age at death from grave 79 was characterised by a plant-based diet. Individuals falling into the Infans I, Infans II and child age categories, due to their likely high milk consumption, were characterised by the highest δ15N parameters, which are characteristic of a ‘pastoral diet’. The range of stable carbon (δ13C) and nitrogen (δ15N) isotope values obtained for the male individuals placed them at a slightly higher trophic level than the females, but these differences were not statistically significant (Mann-Whitney U test: for δ13C p-value 0.88076; for δ15N p-value 0.64552). Individuals of indeterminate sex and age at death displayed a wide range of carbon and nitrogen isotope values.

Aim: The Expansion-Contraction model has been used to explain the responses of species to climatic changes. During periods of unfavourable climatic conditions, species retreat to refugia from where they may later expand. This paper focuses on the palaeoecology of red deer over the past 54 ka across Europe and the Urals, to reveal patterns of change in their range and explore the role of environmental conditions in determining their distribution. Location: Europe and western Asia to 63°E. Taxon: Red deer (Cervus elaphus). Methods: We collected 984 records of radiocarbon-dated red deer subfossils from the Late Pleistocene and the Holocene, including 93 original dates. For each deer sample we compiled climatic and biome type data for the corresponding time intervals. Results: During the last 54 ka changes in red deer range in Europe and the Urals were asynchronous and differed between western and eastern Europe and western Asia due to different environmental conditions in those regions. The range of suitable areas for deer during the Last Glacial Maximum (LGM) was larger than previously thought and covered vast regions not only in southern but also in western and eastern Europe. Throughout the period investigated the majority of specimens inhabited forests in the temperate climatic zone. The contribution of forests in deer localities significantly decreased during the last 4 ka, due to deforestation of Europe caused by humans. Mean January temperature was the main limiting factor for species distribution. Over 90% of the samples were found in areas where mean January temperature was above −10°C. Main conclusions: Red deer response to climatic oscillations are in agreement with the Expansion-Contraction model but in contradiction to the statement of only the southernmost LGM refugia of the species. During the last 54 ka red deer occurred mostly in forests of the temperate climatic zone. © 2020 John Wiley & Sons Ltd. European Social Fund, Grant/Award Number: UDA-POKL.04.01.01-00-072/09-00; University of Wroclaw, Grant/Award Number: 0410/2990/18; Institute of Environmental Biology, University of Wrocław, Grant/Award Number: 0410/2990/18; Mammal Research Institute Polish Academy of Sciences; Narodowe Centrum Nauki , Grant/Award Number: DEC-2013/11/B/NZ8/00888 and UMO-2016/23/B/HS3/00387; Romanian National Authority for Scientific Research, UEFISCDI, Grant/Award Number: PN-IIIP4-ID-PCE-2016-0676; National Centre for Atmospheric Science and the Centre for Environmental Data Analysis, UK; Faunal Database of the Stage Three Project; Leverhulme Trust, Grant/Award Number: F00568W.

In this paper, a record of the 14C and 13C isotope content of atmospheric CO2 for Gliwice is presented for samples collected on a weekly basis in the years 2011–2013. In addition, measurements were performed on the early and late wood from the annual rings of pine trees from five sites located 3–6 km from the atmospheric CO2 sampling point. The concentration of 14C in CO2 samples from the air was much lower relative to the concentration of this isotope in “clean air,” indicating a pronounce Suess effect, with a mean Δ14C lower by ca. 60‰ than Jungfraujoch data when the 15% of the highest differences are excluded, which leads to the FFCO2 estimate of 5.8%. In winter, the main source of fossil CO2 was fuel combustion, as confirmed by significant correlations with air pollutants. In the vegetation seasons, the Δ14C was highly variable due to biogenic influence and more variable winds. The isotopic results were also affected by an additional significant CO2 source for the Gliwice air, which was a closed mine shaft. The Δ14C and δ13C in tree rings did not record a strong Suess effect in the years 2008–2013 in woodland areas around Gliwice city.

Aim The aim was to decipher Europe‐wide spatio‐temporal patterns of forest growth dynamics and their associations with carbon isotope fractionation processes inferred from tree rings as modulated by climate warming. Location Europe and North Africa (30‒70° N, 10° W‒35° E). Time period 1901‒2003. Major taxa studied Temperate and Euro‐Siberian trees. Methods We characterize changes in the relationship between tree growth and carbon isotope fractionation over the 20th century using a European network consisting of 20 site chronologies. Using indexed tree‐ring widths (TRWi), we assess shifts in the temporal coherence of radial growth across sites (synchrony) for five forest ecosystems (Atlantic, boreal, cold continental, Mediterranean and temperate). We also examine whether TRWi shows variable coupling with leaf‐level gas exchange, inferred from indexed carbon isotope discrimination of tree‐ring cellulose (Δ13Ci). Results We find spatial autocorrelation for TRWi and Δ13Ci extending over a maximum of 1,000 km among forest stands. However, growth synchrony is not uniform across Europe, but increases along a latitudinal gradient concurrent with decreasing temperature and evapotranspiration. Latitudinal relationships between TRWi and Δ13Ci (changing from negative to positive southwards) point to drought impairing carbon uptake via stomatal regulation for water saving occurring at forests below 60° N in continental Europe. An increase in forest growth synchrony over the 20th century together with increasingly positive relationships between TRWi and Δ13Ci indicate intensifying impacts of drought on tree performance. These effects are noticeable in drought‐prone biomes (Mediterranean, temperate and cold continental). Main conclusions At the turn of this century, convergence in growth synchrony across European forest ecosystems is coupled with coordinated warming‐induced effects of drought on leaf physiology and tree growth spreading northwards. Such a tendency towards exacerbated moisture‐sensitive growth and physiology could override positive effects of enhanced leaf intercellular CO2 concentrations, possibly resulting in Europe‐wide declines of forest carbon gain in the coming decades. Spanish Government, Grant/Award Number: AGL2015‐68274 ‐C3 ‐3‐R; Sixth Framework Programme, Grant/AwardNumber: EVK2‐2001 ‐00237; Seventh Framework Programme, Grant/AwardNumber: COST ‐STSM ‐ECOST ‐STSM ‐FP1304‐140915‐066395 and ERANET‐Mundus program (Grant agreement 20112573)

Biological studies on Mesolithic human remains from the Polish region are a rare subject of scientific research due to the limited number of these relics and their poor state of preservation. From the project titled “Old material with new methods: Using the latest bio-chemical analysis in studies of Mesolithic human remains from the Polish areas,” the radiocarbon (14C) dating of bones using accelerator mass spectrometry (AMS) has been performed. For these experiments, the gelatin was extracted from bones, and its quality evaluated by the C/Nat ratio and the stable isotope composition of both carbon and nitrogen. The 14C results have been obtained for 11 bone samples from 5 sites, and throughout this work the results of two preparation methods are compared. The simple gelatin extraction provided material with unsatisfactory collagen quality indicators, while additional alkali treatment allowed us to obtain much more reliable, and generally older, results. Additionally, analysis on VIRI/SIRI samples were conducted to test the developed method. Only seven of the investigated bone samples yielded ages within Mesolithic period, and the most reliable dates range from 5800 to 6800 cal BC. One sample was not datable, and two were shown to be much younger than expected.

Stable isotope analyses of bone collagen are often used in palaeoecological studies to reveal environmental conditions in the habitats of different herbivore species. However, such studies require valuable reference data, obtained from analyses of modern individuals, in habitats of well-known conditions. In this article, we present the stable carbon and nitrogen isotope composition of bone collagen from modern red deer (N = 242 individuals) dwelling in various habitats (N = 15 study sites) in Europe. We investigated which of the selected climatic and environmental factors affected the δ13C and δ15N values in bone collagen of the studied specimens. Among all analyzed factors, the percent of forest cover influenced the carbon isotopic composition most significantly, and decreasing forest cover caused an increase in δ13C values. The δ15N was positively related to the proportion of open area and (only in the coastal areas) negatively related to the distance to the seashore. Using rigorous statistical methods and a large number of samples, we confirmed that δ13C and δ15N values can be used as a proxy of past habitats of red deer.

Stable isotope analyses of bone collagen are increasingly used in ecological studies. They are especially valuable in palaeoecological research due to the time of bone collagen preservation. However, such studies are usually subjected to some limitations, such as small size of the dataset and unknown sex or age of analysed individuals, which could potentially influence the results. We investigated variability of stable carbon and nitrogen isotope composition (δ13C and δ15N) within different parts of the skeleton of modern red deer (Cervus elaphus) from Poland, Scotland (UK) and Slovenia. We also tested weather there were differences in isotopic composition of bone collagen between males and females and individuals of different ages representing various populations. The mean differences between samples taken from the same mandibles and between various bones of the same individuals amounted to not more than 0.88‰ (SE ± 0.24) for δ15N and 0.46‰ (SE ± 0.07) for δ13C. Values of δ15N and δ13C in bone collagen did not differ significantly between males and females. Furthermore, we did not find any relationship between isotopic composition of bone collagen and age of the studied individuals. We conclude that carbon and nitrogen isotope ratios in the distal appendicular elements or fragments of mandible bones of the same individuals are comparable and can be alternately used in ecological studies of modern and ancient red deer specimens.

In the current work, we present a complex analysis of the factors influencing the annual increment growth dynamics of Scots pine growing in the vicinity of the steelworks “Huta Katowice” in Dąbrowa Gornicza, Poland. The conifers investigated in this study originated from nine sampling sites and their growth covered the period from 1891 to 2012 AD. A morphologically diverse terrain of research area allowed for comprehensive and detailed analyses that considered a number of factors. We determined the climatic and anthropogenic effects of tree rings width, taking into account spatiotemporal distribution of growth reductions, depth of reduction with respect to distance from the emitter and local morphology, modifications of the relationship between tree growth and climate during the period of development of industry and during the application of a pro-ecological strategy. Common periods of strong growth declines are observed between 1960 and 1980s for most of the investigated sites. The reported results indicate that in terrain of a variable relief, the influence of local factors like morphology might be more important than the distance.

The presented studies were carried out in order to check the usefulness of subfossil wood for stable isotope analysis. The aim of research was also to define the optimal method of subfossil samples preparation. Subfossil samples used during the presented studies are a part of the multicentury dendrochronological scale. This chronology originates in an area situated around a small mountain lake — Schwarzersee, in Austria. The obtained results of stable carbon isotope measurements confirmed that the method of α-cellulose extraction by the application of acidic sodium chlorite and sodium hydroxide solutions removes resins and other mobile compounds from wood. Therefore, in the case of the analysed samples, the additional chemical process of extractives removing was found to be unnecessary. Studied wood samples contained an adequate proportion of α-cellulose similar to the values characteristic for the contemporary trees. This proved an adequate wood preservation which is essential for the conduction of isotopic research.

New results of carbon isotopic composition from tree rings have been analyzed. Δ14C and δ13C data, representing the isotopic composition of carbon in “clean air”, were obtained from annual rings of a pine tree (Pinus sylvestris) taken in the Niepolomice area, 25 km east Krakow, Poland. All samples were processed to extract α-cellulose, and the radiocarbon concentration in each annual ring was measured using AMS at the University of Nagoya. Stable isotopic composition of carbon was determined using isotope ratio mass spectrometry. The dataset covers the growth period between 1960 and 2003. The average difference between radiocarbon concentrations in Niepolomice and the North Hemisphere zone 1 (NH zone 1) for the period between 1960 and 1999 is 3.5 ± 1.6‰. These data are compared with previously presented results from the city of Krakow, where a local decrease in 14C concentration was observed due to local CO2 emission from fossil fuel use. The differences in observed 14C concentrations were used to estimate a magnitude of the local Suess effect in Krakow. Based on mass balance equations for CO2 14C concentrations, it was possible to calculate the CO2 concentration associated with fossil fuel emission (Cfoss) into the atmosphere. The highest values of Cfoss were recorded in the years 1986 (11.9 ± 1.4 ppm V) and 1983 (8.1 ± 1.3 ppm V), while the lowest value of 0.6 ± 1.8 ppm V was recorded in 2001.

Southern Poland is home to numerous large mining and energy industry facilities, which consume relatively great amounts of fossil fuels. Temporal and spatial distribution of CO2 emissions to the atmosphere were estimated on the basis of 13C and 14C isotope measurements in atmospheric CO2 and in α-cellulose from pine tree rings. The Suess effect was evaluated in the atmospheric CO2 from the High Tatra Mountains (Kasprowy Wierch) and the urban area (Kraków), as well as in tree rings from Niepołomice Forest near Kraków. Two different models were used to estimate the emission component recorded in tree ring δ13C on the background of climatic changes.

New records of δ13C and Δ14C values in annual rings of pine and oak from different sites around the world were obtained with a time resolution of 1 yr. The results obtained for Europe (Poland), east Asia (Japan), and South America (Peru) are presented in this paper. The δ13C and radiocarbon concentration of α-cellulose from annual tree rings of pine and of the latewood of oak were measured by both accelerator mass spectrometry (AMS) and liquid scintillation spectrometry (LSC). The values of 14S, which represent decreasing 14C concentrations caused by the emission of CO2 from fossil fuel use (Suess effect; Suess 1955), were calculated for each site. Low average 14S (about −0.4 to 0.8%) values for clean areas and high values (about 3.4–3.6%) for industrial and/or urbanized areas were noted. Records of the δ13C values obtained for pine and oak from Poland were used to reconstruct climate changes during the last 400 yr. The results clearly indicate the climate cooling during the periods of the Maunder minimum (1645–1715) and the Dalton minimum (1790–1820). The anti-correlation between the δ13C and Δ14C records during those 2 periods is clear if the 14C record is shifted toward older ages by 24 yr.

Considering the combined effects of CO2 fertilization and climate change drivers on plant physiology leads to a modest increase in simulated European forest transpiration in spite of the effects of CO2-induced stomatal closure. The Earth’s carbon and hydrologic cycles are intimately coupled by gas exchange through plant stomata1,2,3. However, uncertainties in the magnitude4,5,6 and consequences7,8 of the physiological responses9,10 of plants to elevated CO2 in natural environments hinders modelling of terrestrial water cycling and carbon storage11. Here we use annually resolved long-term δ13C tree-ring measurements across a European forest network to reconstruct the physiologically driven response of intercellular CO2 (Ci) caused by atmospheric CO2 (Ca) trends. When removing meteorological signals from the δ13C measurements, we find that trees across Europe regulated gas exchange so that for one ppmv atmospheric CO2 increase, Ci increased by ∼0.76 ppmv, most consistent with moderate control towards a constant Ci/Ca ratio. This response corresponds to twentieth-century intrinsic water-use efficiency (iWUE) increases of 14 ± 10 and 22 ± 6% at broadleaf and coniferous sites, respectively. An ensemble of process-based global vegetation models shows similar CO2 effects on iWUE trends. Yet, when operating these models with climate drivers reintroduced, despite decreased stomatal opening, 5% increases in European forest transpiration are calculated over the twentieth century. This counterintuitive result arises from lengthened growing seasons, enhanced evaporative demand in a warming climate, and increased leaf area, which together oppose effects of CO2-induced stomatal closure. Our study questions changes to the hydrological cycle, such as reductions in transpiration and air humidity, hypothesized to result from plant responses to anthropogenic emissions.

Tree rings can be used as archives of climatic and environmental data with annual resolution. Tree rings widths, maximum late wood density and other parameters as stable composition in tree rings can be used for the reconstruction of past climatic and environmental changes. Stable carbon isotope ratios in tree rings may provide valuable information on past climatic conditions. 13C/12C ratios of plant organic matter can reflect corresponding 13C/12C ratio of atmospheric CO2 during formation of the rings. Investigations of isotopic carbon composition in tree rings from in the ecologically clean the Augustów Wilderness region in the north-eastern part of Poland (22 degrees 58'E, 53 degrees 51'N) (nowadays a sanctuary) were undertaken. Series of delta13C in alpha-cellulose and in wholewood were acquired. Those measurements constituted a part of more complex investigations of carbon isotope composition in tree rings including the measurements of radiocarbon concentration and tree ring widths. This article presents preliminary results. It is argued that contrary to the tree ring widths and delta13C in wholewood that do not reveal significant correlation with temperature, the variation of delta13C in the latewood alpha-cellulose is correlated with combined July and August temperatures.

Carbon isotopes are widely used as indicators in the study of atmospheric CO2 variability in space and time. Preliminary results are part of a project investigating 13C and 14C concentration changes during the last 150 yr in Poland, both in industrial and ecologically clean regions, using annual tree rings (Pinus sylvestris, Populus nigra). The results describe the local Suess effect recorded in the industrial Kraków and Upper Silesia regions compared to changes of background radiocarbon concentration caused by global human activity in a “clean region,” Augustów Wilderness. The δ13C record also shows the influence of the local Suess effect.

Cellulose delta18O and deltaD can provide insights on climates and hydrological cycling in the distant past and how these factors differ spatially. However, most studies of plant cellulose have used only one isotope, most commonly delta18O, resulting in difficulties partitioning variation in delta18O of precipitation vs. evaporative conditions that affect leaf water isotopic enrichment. Moreover, observations of pronounced diurnal differences from conventional steady-state model predictions of leaf water isotopic fractionation have cast some doubt on single isotope modeling approaches for separating precipitation and evaporation drivers of cellulose delta18O or deltaD. We explore a dual isotope approach akin to the concept of deuterium-excess (d), to establish deuterium deviations from the global meteoric water line in leaf water (deltad(l)) as driven by relative humidity (RH). To demonstrate this concept, we survey studies of leaf water delta18O and deltaD in hardwood vs. conifer trees. We then apply the concept to cellulose delta18O and deltaD using a mechanistic model of cellulose delta18O and deltaD to reconstruct deuterium deviations from the global meteoric water line (deltad(c)) in Quercus macrocarpa, Q. robur, and Pseudotsuga menziesii. For each species, deltad(c) showed strong correlations with RH across sites. deltad(c) agreed well with steady-state predictions for Q. macrocarpa, while for Q. robur, the relationship with RH was steeper than expected. The slope of deltad(c) vs. RH of P. menziesii was also close to steady-state predictions, but deltad(c) were more enriched than predicted. This is in agreement with our leaf water survey showing conifer deltad(l) was more enriched than predicted. Our data reveal that applications of this method should be appropriate for reconstructing RH from cellulose delta18O and deltaD after accounting for differences between hardwoods and conifers. Hence, deltad(c) should be useful for understanding variability in RH associated with past climatic cycles, across regional climates, or across complex terrain where climate modeling is challenging. Furthermore, deltad(c) and inferred RH values should help in constraining variation in source water delta18O.

We present the first European network of tree ring delta(13)C and delta(18)O, containing 23 sites from Finland to Morocco. Common climate signals are found over broad climatic-ecological ranges. In temperate regions we find positive correlations with summer maximum temperatures and negative correlations with summer precipitation and Palmer Drought Severity Indices (PDSI) with no obvious speciesspecific differences. Regional delta(13)C and delta(18)O chronologies share high common variance in year-to-year variations. Long-term variations, however, exhibit differences that may reflect spatial variability in environmental forcings, age trends and/or plant physiological responses to increasing atmospheric CO(2) concentration. Rotated principal component analysis (RPCA) and climate field correlations enable the identification of four sub-regions in the delta(18)O network - northern and eastern Central Europe, Scandinavia and the western Mediterranean. Regional patterns in the delta(13)C network are less clear and are timescale dependent. Our results indicate that future reconstruction efforts should concentrate on delta(18)O data in the identified European regions.