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Agrarian stone walls and associated landscapes are present in different parts of Central and Western Europe. Somewhere they are conserved as valuable components of cultural landscapes whereas elsewhere they do not have any formal conservation status. These stone walls and the habitats connected to them host many old trees, which are potential archives of environmental changes. In the available literature there are practically no studies looking at the archival value of trees on agrarian stone walls. In our study we investigated sycamore maples growing on stone walls in the Ore Mts region of Czechia. We focussed on annual wood growth using dendrochronological methods and carried out pointer year analyses to examine environment-growth relationships. Our main findings suggest moderately heterogeneous growth among individuals within sites but that there is a common environmental response apparent in overall site chronologies. We observed low inter-series correlations within sites but only a fair to moderate Gleichläufigkeit and express population signal among ring width series at most of the study sites. Generally, we revealed mostly significant positive correlations with precipitation and negative correlations with increasing temperatures over the last years. From climate correlations analysis and pointer year analysis we could clearly infer that (1) tree growth on agrarian stone walls at three out of four of our sites is significantly impacted by current climate change and that (2) these trees have a good ecological-archival value because they are sensitive to contemporary warming; they should therefore be identified to be given a relevant conservation status and management.

The Arctic, one of the most sensitive components of the Earth's climate system, experienced pronounced climatic fluctuations during the Late Holocene. In order to obtain a detailed record of past environmental and climatic variability, sedimentary cores from two interconnected infilled depositional basins in the Kobbefjord area, southwestern Greenland, were retrieved and subjected to a multi-proxy investigation. The absolute chronostratigraphy was established through radiocarbon (C-14) and short-lived radioisotope (Pb-210, Cs-137) dating. We also analysed magnetic susceptibility, grain size, X-ray fluorescence element composition, total content of carbon, nitrogen and sulphur, biogenic silica and diatom assemblages. The palaeoenvironmental reconstruction presented from the upper basin records similar to 800 years of sedimentation in a former shallow Arctic lake/pond that was modulated by catchment processes and regional hydroclimate. The record is dominated by alternating periods of increased organic and clastic deposition, suggesting warmer/drier and colder/wetter climate, respectively. Comparison of our records with other proxy-based lacustrine, marine and glacier records and instrumental measurements from Greenland and the North Atlantic reveals common climatic trends, consistent with the inferred North Atlantic Oscillation pattern. Periods at similar to 800-600, similar to 320-220 and similar to 140-30 cal. a BP correspond to the main cold phases. The earliest climatic deterioration coincides with the demise of the nearby Norse Western Settlement. The most recent cold period represents the culmination of the Little Ice Age with the maximum Holocene advances of Greenland glaciers. Ameliorated conditions predominated at similar to 550-320 and similar to 220-140 cal. a BP. The evolution of both water bodies is concluded by transition into oligotrophic peat bogs after complete infilling of the basins at similar to 30 cal. a BP. Despite differences in proxy signals between the coring sites, this study endorses the usefulness of shallow lake/pond sediments from infilled basins for environmental reconstructions, as long as local depositional processes do not mask the external driving factors.

The paper aims to reveal the meanings attached to agricultural land by its owners and municipal representatives. The way farmland is used influences how municipalities can reduce the negative impacts of climate change on their territory. Therefore, the paper seeks to further capture the motivations for farming by local owners and their connection to the environmental context. The research is based on personal questionnaire survey with landowners and interviews with municipal representatives in three model localities in the Czech Republic (Pohořelice, Valašsko-Kloboucko and Tišnov). According to the findings, the land is perceived as a valuable commodity, associated with heritage and tradition. From the point of view of local owners, it was associated with an investment, from the point of view of municipalities as a means of influencing the future direction of the municipality. The link between land ownership and environmental issues (e.g. the ability to influence the effects of climate change manifestations at the local level) was very weak.

Citizen science is a relatively new phenomenon in the Czech Republic and currently a general overview of existing citizen science projects is not available. This presents the challenge to uncover the 'hidden' citizen science landscapes. The main objective of this paper is to explore the (public) representation of citizen science (CS) projects and to describe their heterogeneity. The study aims to answer the question of what type of projects in the Czech Republic meet the definition of citizen science. Based on a specific methodological data-base search approach, we compiled a set of CS projects (N = 73). During the classification process, two general citizen science categories were identified. The first group (N = 46) consists of "pure" CS projects with a prevalence towards the natural sciences, principally ornithology, and thus corresponding to general European trends. Citizens usually participate in such research in the form of data collection and basic interpretation, and a high level of cooperation between academia and NGOs was detected. The second group of "potential" CS projects (N = 27) entails various forms of public participation in general, frequently coordinated by NGOs. Based on these results, we discuss the position of citizen science in the Czech Republic, including socially-oriented citizen science. Further research is strongly encouraged to achieve a more in-depth insight into this social phenomenon., INTER-COST project: Geographical aspects of Citizen Science: Mapping trends, scientific potential and societal impacts in the Czech Republic [LTC18067]

Arctic shrubs have a strong potential for climate and environmental reconstructions in the chronically understudied regions of the high northern latitudes. The climate dynamics of these regions are important to understand because of large-scale feedbacks to the global climate system. However, little is known about other factors influencing shrub ring growth, possibly obscuring their climate signal. For example, as of yet we are not able to differentiate between herbivory or climatically induced growth depressions. Here, we use one of the most common Arctic shrubs, Alnus viridis as a test case to address this question. We sampled Alnus in Kobbefjord, Greenland, measured shrub-ring width and cell wall thickness and built site chronologies of each parameter. We analysed climate-growth relationships, tested their stability over time and employed a pointer-year analysis to detect growth depressions. We employed bootstrapped transfer function stability tests (BTFS) to assess the suitability of our shrub chronologies for climate reconstruction. Correlations with climate data showed strong significantly positive and stable correlations between summer temperature and ring-width with the exception of the recent decade. A climate reconstruction model failed stability tests, when the complete period of record was used for calibration and verification. Wood anatomy analysis uncovered the occurrence of unusual cell structure (very thin cell walls) in the exceptionally narrow ring of 2004, a recorded insect outbreak year in other parts of Greenland. When excluding the affected ring and a recovery period, the reconstruction model passed all tests, suggesting that the unusual 2004 ring was not climate driven, but rather the result of an insect attack. When combining anatomical analysis with traditional ring-width measurements, we move a step further in potentially distinguishing small rings caused by insect attacks from small rings formed in climatically challenging years. While this study does not provide unambiguous evidence, it does provide potential useful methodological combinations to enable more robust climate reconstructions in areas where climatic records are extremely sparse.

Camera traps are increasingly one of the fundamental pillars of environmental monitoring and management. Even outside the scientific community, thousands of camera traps in the hands of citizens may offer valuable data on terrestrial vertebrate fauna, bycatch data in particular, when guided according to already employed standards. This provides a promising setting for Citizen Science initiatives. Here, we suggest a possible pathway for isolated observations to be aggregated into a single database that respects the existing standards (with a proposed extension). Our approach aims to show a new perspective and to update the recent progress in engaging the enthusiasm of citizen scientists and in including machine learning processes into image classification in camera trap research. This approach (combining machine learning and the input from citizen scientists) may significantly assist in streamlining the processing of camera trap data while simultaneously raising public environmental awareness. We have thus developed a conceptual framework and analytical concept for a web-based camera trap database, incorporating the above-mentioned aspects that respect a combination of the roles of experts’ and citizens’ evaluations, the way of training a neural network and adding a taxon complexity index. This initiative could well serve scientists and the general public, as well as assisting public authorities to efficiently set spatially and temporarily well-targeted conservation policies. © 2021 by the authors. Licensee MDPI, Basel, Switzerland., TA C. R [TG03010052]; INTER-COST project Geographical Aspects of Citizen Science: mapping trends, scientific potential and societal impacts in the Czech Republic [LTC18067, CA15212A], TG03010052; European Cooperation in Science and Technology, COST; LTC18067

The Arctic is one of the most sensitive areas worldwide with respect to climate changes, and recent climate change impacts are evident throughout Arctic ecosystems. In order to put current and projected changes in a palaeoclimatic context, exact information of past conditions and therefore detailed knowledge of proxy archives are crucial. Here, we investigated wood anatomical and other growth-related records of the long-lived and widespread Arctic tundra shrub Juniperus communis L. Annual ring-widths and cell anatomical parameters of 20 individuals from south-west Greenland were measured to test for age-related trends in the proxy time series and to correlate them with past climatic conditions. We documented a clear age trend in the investigated growth parameters (ring-widths, conduit-lumen areas, and cell wall thicknesses), which indicates the need for detrending the time series prior to possible climate correlation analyses and climate or environmental reconstructions. Prostrate growth forms of J. communis do not exhibit the general trend of an exponential widening of the conduit-lumen areas during ontogeny, as has been observed for many tree species, but their conduit lumens stop to increase in size at some point. This is possibly caused by a combination of extreme climate and physiological adaptations, which result in a prostrate growth form. Of the tested growth parameters, only detrended cell wall thickness showed stable correlations with summer temperature and the summer standardized precipitation evapotranspiration index (SPEI). The other growth parameters did not pass cross-calibration verification analyses, although for ring-widths we found the strongest climate correlations. Despite the fact that the ecophysiological processes behind our observations (i.e. reduced cell wall thickness combined with wider rings under dry conditions in the vegetation season) yet are not fully understood, we recognize the potential of J. communis for climate reconstructions. To our knowledge, this is the first demonstration of using cell anatomical parameter of J. communis shrubs as palaeoclimatological proxy for the Arctic.

The Arctic is the most sensitive zone to climate changes and the impacts are reflected in local ecosystems. In order to extract information of the past from proxy archives the detailed knowledge of such archive is crucial. The paper summarizes modern approaches of tundra dwarf shrub research for the purposes of paleoclimatology. Dwarf tundra shrubs as still relatively untapped archive are believed to contain valuable proxy data in their annual growth increments. Field sampling, and laboratory work are reviewed in detail. Constraints of dwarf tundra shrub research are discussed as well. The relationship between climate and growth is addressed to find a link between them depending on location and species. Majority of investigations found the strongest relationship between summer temperatures and ring widths, although exceptions are not rare. Dwarf tundra shrubs can fully serve as valuable proxy archive only if those are understood. Finally, the factors influencing the length of dwarf tundra shrub life are studied in order to sample the oldest living individuals in the field. Despite the field collection should aim to sample various sizes and ages of plants to make the dataset robust, the longest living individuals which are important to prolong chronologies are usually inhabiting rather nutrient poor and undisturbed sites close to their survival limits. The paper indicates the most suitable dwarf tundra shrub research designs for the purposes of paleoclimatology. As such it can help to harvest the benefits of dendrochronology from the vast and new territories.

Large spatial and between-tree variability has recently been observed in the response of boreal forests to ongoing climate change, spanning from growth stimulation by increasing temperatures to drought limitation. To predict future responses of boreal forests, it is necessary to disentangle the drivers modulating the temperature-growth interaction. To address this issue, we established two inventory plots (at a treeline and closed-canopy forest) and assembled site chronologies in Picea glauca stands at the transition between boreal forest and tundra in Northern Quebec, Canada. In addition to site chronologies, we established a set of chronologies containing, for each year, exclusive subsets of tree-rings with specific cambial age (young/old), tree dimensions (small/large) and tree social status (dominant/suppressed). All chronologies were correlated with climatic data to identify the course of climatic conditions driving variability in tree-ring widths. Our results show that the growth of P. glauca correlates significantly with summer temperature in tree-ring formation years and during up to two prior summers. Tree-ring width is positively influenced by summer temperatures in tree-ring formation year and two years prior to tree-ring formation. In addition, climate-growth correlations indicate a negative effect of summer temperature one year before tree-ring formation at the closed-canopy forest site. The pattern of climate-growth correlations is tightly synchronized with previously published patterns of climate-reproduction correlations of P. glauca, suggesting a growth-reproduction trade-off as a possible factor modulating the response of boreal forests to summer temperatures. Climatic signal does not differ between pairs of chronologies based on subsets of cambial ages, stem dimensions or tree competition status at the treeline site. However, the response to summer temperatures one year before tree-ring formation is significant only in mature (old, large and dominant) individuals at the closed-canopy site. The inverse pattern of temperature-growth correlations during a sequence of three years challenges predictions of how boreal forests respond to climate change., European Union's Horizon 2020 project INTERACT [730938]; Charles University [UNCE/HUM 018]

Questions How have the historical frequency and severity of natural disturbances in primary Picea abies forests varied at the forest stand and landscape level during recent centuries? Is there a relationship between physiographic attributes and historical patterns of disturbance severity in this system? Location Primary P. abies forests of the Eastern Carpathian Mountains, Romania; a region thought to hold the largest concentration of primary P. abies forests in Europe's temperate zone. Methods We used dendrochronological methods applied to many plots over a large area (132 plots representing six stands in two landscapes), thereby providing information at both stand and landscape levels. Evidence of past canopy disturbance was derived from two patterns of radial growth: (1) abrupt, sustained increases in growth (releases) and (2) rapid early growth rates (gap recruitment). These methods were augmented with non-metric multidimensional scaling to facilitate the interpretation of factors influencing past disturbance. Results Of the two growth pattern criteria used to assess past disturbance, gap recruitment was the most common, representing 80% of disturbance evidence overall. Disturbance severities varied over the landscape, including stand-replacing events, as well as low- and intermediate-severity disturbances. More than half of the study plots experienced extreme-severity disturbances at the plot level, although they were not always synchronized across stands and landscapes. Plots indicating high-severity disturbances were often spatially clustered (indicating disturbances up to 20 ha), while this tendency was less clear for low- and moderate-severity disturbances. Physiographic attributes such as altitude and land form were only weakly correlated with disturbance severity. Historical documents suggest windstorms as the primary disturbance agent, while the role of bark beetles (Ips typographus) remains unclear. Conclusions The historical disturbance regime revealed in this multi-scale study is characterized by considerable spatial and temporal heterogeneity, which could be seen among plots within stands, among stands within landscapes and between the two landscapes. When the disturbance regime was evaluated at these larger scales, the entire range of disturbance severity was revealed within this landscape.

The objective of this study were Little Ice Age (LIA) to recent subglacial tills, glaciofluvial sediments of proglacial sandur, esker sediments and sediments of moraine-mound complexes of Hrbyebreen polythermal valley glacier and LIA to recent sediments of lateral moraine, frontal moraine, ice-cored moraine and glaciofluvial sediments of proglacial sandur of Bertilbreen polythermal valley glacier. Fossil (probably early Holocene) subglacial and supraglacial tills and sediments of coarse-grained glaciomarginal delta of Bertilbreen have also been studied. The research focused on Old Red sandstone clasts, for which roundness, shape and striation presence have been investigated. The results from this research led to the proposal of new methodological approaches. It is mainly the covariant plot of striations and RA (the share of striated clasts versus the share of very angular and angular clasts), which effectively differentiate subglacial tills from glaciofluvial sediments and allows for identification of the source material of moraine-mound complexes, especially the oldest, more degraded parts near the maximum LIA glacier extent. The second is the covariant plot of distance and RS index (the distance from the starting point versus the share of subangular and subrounded clasts) to present downstream roundness trends in proglacial glaciofluvial sediments. The research confirmed the crucial role of lithological properties of thinly bedded rocks on the shape of these rock clasts in sediment and a minimum impact of passive and active transport on the clast shape modification.