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This paper is an introduction to a collection of nine studies that are intended to fill the gap in the literature associated with landform development and landscape changes related to natural forces and human activities in the Central European Mountains and their close forelands. The papers are grouped into four general categories that describe the influence of climate on glacial landforms and snow avalanches, the evolution of slopes in high mountains, the development of mid-mountain relief, and changes in fluvial systems in mountains and their forelands. This paper summarises the contributions of these studies to this special issue and attempts to outline possible avenues of future research on landforms and landscapes in mountainous areas. [ABSTRACT FROM AUTHOR]

Along with predicted climate change, increased risks for summer drought are projected for Central Europe. However, large knowledge gaps exist in terms of how drought events influence the short-term ecosystem carbon cycle. Here, we present results from 13CO2 pulse labeling experiments at an intensively managed lowland grassland in Switzerland. We investigated the effect of extreme summer drought on the short-term coupling of freshly assimilated photosynthates in shoots to roots as well as to soil CO2 efflux. Summer drought was simulated using rainout shelters during two field seasons (2010 and 2011). Soil CO2 efflux and its isotopic composition were measured with custom- built chambers coupled to a quantum cascade laser spectrometer (QCLAS-ISO, Aerodyne Research Inc., MA, USA). During the 90min pulse labeling experiments, we added 99.9atom% 13CO2 to the grass sward. In addition to the isotopic analysis of soil CO2 efflux, this label was traced over 31 days into bulk shoots, roots and soil. Drought reduced the incorporation of recently fixed carbon into shoots and increased carbon allocation below-ground relative to total tracer uptake. Contrary to our hypothesis, we did not find a change in allocation speed in response to drought, although drought clearly reduced soil CO2 efflux rates. 19 days after pulse labeling, only about 60 % of total tracer uptake was lost via soil CO2 efflux under drought compared to about 75 % under control conditions. Predisposition of grassland by spring drought lead to different responses to summer drought in 2011 compared to 2010, suggesting increased sensitivity of grassland to consecutive drought events as predicted under future climate change. [ABSTRACT FROM AUTHOR]

Within the context of tourism development in the countries of contemporary Central and Eastern Europe, this paper briefly discusses the challenges for industry and key issues for researchers within six broad topic areas. These are: climate change adaptation and mitigation; integration with sustainable development strategies; coping with globalization; differentiation/ uniqueness; innovation; and collaboration/ partnership/ networking. Practical cases are drawn from Western European experience to exemplify potential opportunities, and recent published research is identified to inform fruitful research directions. It is concluded that challenges and issues are similar across Europe, and that those relating to climate change adaptation and mitigation are, in the wider context, the most important to understand and address. [ABSTRACT FROM AUTHOR]

The paper reports on a study of extremely cool summers (ECS), a rare but significant phenomenon responsible for various adverse economic effects. These include, in particular, effects on agriculture and the tourist industry. The seasons, their spatial extent and individual characteristics were identified in Central and Eastern Europe. The research was based on average seasonal air temperatures (June to August) and the numbers of days with maximum temperatures >25, 30 and 35 °C and minimum temperatures >20 °C, as recorded at 59 weather stations during the period 1951-2010. An ECS was defined as having an average temperature at least 2 standard deviations (t ≤ t − 2σ) lower than the average at a given station during the study period. ECS occurred at only 34 of the 59 stations (58 % of all stations), one or two per station, mainly in the northern part of the study area. Six such seasons were recorded by at least 5 % of all stations in 1962, 1969, 1976, 1978, 1984 and 1994. The average temperature of an ECS was typically 2-3 °C lower than the long-term average. While some ECSs included an extremely cool month, most such seasons (58 %) were defined by low temperatures persisting for long periods in all summer months. [ABSTRACT FROM AUTHOR]

Abstract: With a predicted rise in average global surface temperature at an unprecedented rate, as well as changes in precipitation and disturbance regimes, climate change will bring forth new challenges for nature conservation in forest ecosystems. Species and habitats to be protected will be affected as well as related concepts and area specific objectives. Climate change impacts are likely to be aggravated by other anthropogenic stresses such as fragmentation, deposition or habitat destruction. To be reliable and effective, current objectives and guidelines of forest conservation need to be reassessed and improved. Our study analyses possible impacts of climate change on forests and identifies key future challenges for nature conservation in forests and ecosystem research. We reviewed 130 papers on climate change impacts on forest ecosystems and species published between 1995 and 2010. The geographical focus of the study is Central Europe. Papers were analysed accounting for direct and indirect impacts of gradual changes as well as stochastic disturbance events in forest ecosystems and their possible consequences for nature conservation. Even though broader aspects of nature conservation (protected areas, biodiversity) are frequently mentioned, little attention is given to forest-specific nature conservation. Particular aspects are insufficiently represented, such as the influence of climate change on different forest succession stages, the development of dead wood volume and quality, responses of secondary broadleaved species, azonal or extrazonal forests as well as ancient woodlands or remnants of historical silvicultural systems. Challenges arise in the context of great uncertainties about future developments. Nature conservation concepts and objectives in forests need to be adapted either within a permanent evaluation process or through the inclusion of further changes a priori, even if they are to some extent unpredictable. In some cases adaptation measures within nature conservation (e.g. adjusting protected areas) may conflict with interests of other stakeholders. Further research, particularly on interrelations between different impacts and the adaptive capacity of current forest ecosystems, associated species and existing genotypes is urgently needed. The scale and complexity of the task at hand calls for the establishment and further strengthening of international research networks. [Copyright &y& Elsevier]

Bösken et al. (2017) aimed at contributing to the environmental variability of the Gravettian population in ‘southeastern’ Europe during the Last Glacial Maximum (LGM) with an interdisciplinary study at the Upper Palaeolithic site Ságvár Lyukas Hill (Hungary). However, the classification of the site as Gravettian is erroneous because the LGM archaeological record of eastern central Europe is composed of findings of another culture, the Epigravettian. This short comment on the paper of Bösken et al. (2017) presents the archaeological chronology between 34 and 16 kyr BP with a focus on the Gravettian–Epigravettian dichotomy. [ABSTRACT FROM AUTHOR]

Climate change effects such as storms and droughts are leading to increased risk of forest damage in central Europe. The aim of this paper was to evaluate forest fuel sourcing models including climate change-induced risks on forest fuel supply. Stochastic risk events, such as storms and bark beetle infestations, were modelled by means of a Monte Carlo simulation, and the economic performance was evaluated for two fuel-sourcing models supplying a single combined heat and power plant (CHP). The first sourcing model depicted a common sourcing model for Austrian CHPs, where only forest chips provided by long- and short-term suppliers were stored. The second sourcing model additionally enabled the storage of salvaged pulpwood to supply forest fuel from the plant's own inventory during shortage periods. Simulation results showed that storing salvage pulpwood as feedstock considerably reduced supply chain risks and resulted in lower procurement costs (1-3% less than normal delivered cost without storing salvaged pulpwood). [ABSTRACT FROM AUTHOR]

Climatic warming may lead to increased or decreased future forest productivity. However, more frequent heat waves, droughts and storms and accompanying pathogen attacks are also expected for Europe and are considered to be increasingly important abiotic and biotic stress factors for forests. Adaptive forestry can help forest ecosystems to adapt to these new conditions in order to achieve management goals, maintain desired forest ecosystem services and reduce the risks of forest degradation. With a focus on central Europe, this paper presents the following management strategies: (1) conservation of forest structures, (2) active adaptation, and (3) passive adaptation. The feasibility and criteria for application of the different strategies are discussed. Forest adaptation may entail the establishment of “neonative” forests, including the use and intermixing of native and non-native tree species as well as non-local tree provenances that may adapt better to future climate conditions. An integrative adaptive management concept is proposed that combines (1) species suitability tests and modelling activities at the international scale, (2) priority mapping of adaptation strategies at the national to regional scale, and (3) implementation at the local scale. To achieve this, an international experimental trial system is required to test suitable adaptive measures throughout Europe and worldwide. [ABSTRACT FROM AUTHOR]

Central and Eastern Europe (CEE) is a rapidly changing and developing region which is making the transition to a market based economy. Along with economic reforms, the countries of the region are engaged in substantial environmental reforms, including climate change mitigation activities. Mitigation of, and adaptation to, the consequences of climate change are costly processes. It is therefore of great importance that the national and international mechanisms addressing these problems use methods both environmentally sound and economically efficient. Through two case studies that address the Clean Development Mechanism (CDM) in the Former Yugoslav Republic of Macedonia, and the Green Investment Scheme (GIS) in Romania, this paper explores challenges, related tasks and main problems in the establishment of mechanisms of the Kyoto Protocol in Central and Eastern Europe. [ABSTRACT FROM AUTHOR]

During the last two decades significant socio-economic and environmental changes took place in Central and Eastern Europe (CEE), including collapse of the old socio-economic systems and climate change. The main objective of the paper is to analyse changes in water resources in the region and to relate them either to ongoing climate change or to socio-economic changes in the region, where possible. Two basins located in the Eastern part of Germany and in the Western part of Poland were taken as case study areas. An attempt to compare changes of water resources triggered by socio-economic and environmental (therein climate) changes was undertaken, including quantitative assessment of relative magnitudes of impacts, where feasible. The impacts on both water quantity and water quality aspects were investigated, considering changes in river discharge, groundwater dynamics, water demand, point and non-point source pollution in both basins under study. Where necessary, the analysis of data was supported by modelling results. The analysis reported confirms that until now the changes in socio-economic systems have impacted regional water resources in a more significant way than the climate change. However, the impacts of climate change on water resources in the study regions are likely to increase in the future, warmer climate, as projected by the existing scenarios. [ABSTRACT FROM AUTHOR]

On the basis of glacier and lake-level records, this paper attempts, for the first time, a comparison between high-resolution palaeohydrological and palaeoglaciological data in west-central Europe over the past 3500 years. A data set of tree-ring width, radiocarbon and archaeological data, in addition to historical sources, were used to reconstruct fluctuations of the Great Aletsch, the Gorner and the Lower Grindelwald glaciers in the Swiss Alps. The three ice-streams experienced nearly synchronous advances at c. 1000–600 BC and AD 500–600, 800–900; 1100–1200 and 1300–1860. These glacier fluctuations show strong correspondence with lake-level variations reconstructed in eastern France (Jura mountains and Pre-Alps) and on the Swiss Plateau. This supports the hypothesis of elimatically driven fluctuations. Historical date available for the period since AD 1550 reveal, in detail, various meteorological conditions behind the succesive glacier advances. Howere, in agreement with the general trend shown by the historical data, the synchroneity between glacier advances and periods of higher lake level suggests the impact of general winter cooling and an increase in summer moistur as responsible for reinforced feeding of both glaciers and lakes in west-central Europe ;over the past 3500 years. Finally, comparison between the Great Aletsech glacier and the residual 14C records supports the hypothesis that variations in solar activity were a major forcing factor of climatic oscillations in west-central Europe during the last Holocence. [ABSTRACT FROM AUTHOR]

Background: Ongoing climate change is anticipated to increase the frequency and intensity of drought events, thereby affecting forest recovery dynamics and elevating tree mortality. The drought of 2018, with its exceptional intensity and duration, had a significant adverse impact on tree species throughout Central Europe. However, our understanding of the resistance to and recovery of young trees from drought stress remains limited. Here, we examined the recovery patterns of native deciduous tree sapling species following the 2018 drought, and explored the impact of soil depth, understory vegetation, and litter cover on this recovery. Methods: A total of 1,149 saplings of seven deciduous tree species were monitored in the understory of old-growth forests in Northern Bavaria, Central Germany. The vitality of the saplings was recorded from 2018 to 2021 on 170 plots. Results: Fagus sylvatica was the most drought-resistant species, followed by Betula pendula, Acer pseudoplatanus, Quercus spp., Corylus avellana, Carpinus betulus, and Sorbus aucuparia. Although the drought conditions persisted one year later, all species recovered significantly from the 2018 drought, albeit with a slight decrease in vitality by 2021. In 2018, the drought exhibited a more pronounced adverse effect on saplings in deciduous forests compared to mixed and coniferous forests. Conversely, sapling recovery in coniferous and mixed forests exceeded that observed in deciduous forests in 2019. The pivotal factors influencing sapling resilience to drought were forest types, soil depth, and understory vegetation, whereas litter and forest canopy cover had a negative impact. Conclusion: Long-term responses of tree species to drought can be best discerned through continuous health monitoring. These findings demonstrate the natural regeneration potential of deciduous species in the context of climate change. Selective tree species planting, soil management practices, and promoting understory diversity should be considered when implementing adaptive management strategies to enhance forest resilience to drought events. [ABSTRACT FROM AUTHOR]

Climate change is likely to exacerbate the negative effects of invasive alien species (IAS) as it will foster their further spread. This paper analyses the potential socio-economic effects of three emerging IAS (giant ragweed, Ambrosia trifida ; annual wormwood, Artemisia annua ; and burweed marshelder, Iva xanthiifolia ), which are known to cause substantial harm to human health and to have negative effects on agricultural production. The novelty of the study consists in an integrated approach that combines several aspects of IAS research and management. We model the future spread of the study species in Central Europe by the year 2050 under several climate change, management and spread scenarios. The costs and benefits of controlling the expansion of these IAS are based on this forecast. The results show that an early and coordinated response to the spread of these IAS yields substantial net benefits under all scenarios. Under the conditions of moderate climate change (+1.5 °C), discounted net benefits range from €19 to €582 million. Assuming more severe climate change (+2.4 °C), total savings over the full period are projected to add up to €1063 million. These large socio-economic benefits provide compelling evidence that public authorities should act preventively to restrict the spread of these three IAS. [ABSTRACT FROM AUTHOR]

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 ka. 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. [ABSTRACT FROM AUTHOR]

Abstract: Anthropogenic effects on rivers, including engineering regulation, hydropower usage, and water pollution, not only change bed morphology and/or water quality but also affect the river ice regime. The length of the ice-affected season and the relative frequency of ice appearance might alter due to anthropogenic activities. Moreover, anthropogenically induced changes may vastly exceed climatic effects. When the prevailing non-natural impact co-varies with the trend of the expected climate trigger (e.g. winter air temperature), conclusions can be biased if the anthropogenic effects were not scrutinized in depth. This paper presents examples when changes in some characteristic feature of the river ice regime are related to human activities. These simple tests could be applied for other rivers, where similar anthropogenic impacts may be suspected to affect the river ice regime. [Copyright &y& Elsevier]

Abstract: This paper presents a fresh examination of a pollen profile from Ustków (central Poland), which after preliminary results was thought to span a period between the Early Eemian (MIS 5e) and the upper Pleni-Weichselian (MIS 3). The newly obtained results confirmed the age assessment of the bottom series, but revealed a much older age for the uppermost part of the profile as far back as the Rederstall stadial (MIS 5b). Palynological research showed slightly different patterns of vegetation in comparison to other sites located in Central Europe. Among them were an early Ulmus maximum coinciding with the Betula optimum in the Early Eemian, a relatively late optimum of Taxus baccata during the decline of the Middle Eemian, and a distinct division of the older part of the Late Eemian into phases of Abies-Picea and Picea-Pinus forest domination. The Herning stadial (MIS 5d) falls into a typical bipartition reflected by heathland domination during its older part and the prevalence of Juniperus thickets and Artemisia-Poaceae steppe during its younger part, which makes this succession similar to those from northern Germany. The pollen spectra reflecting the Brørup interstadial (MIS 5c) distinctly revealed an intra-Brørup cold oscillation rarely detected in profiles from Central Europe and a period of Larix dominated forests during the latest part of the interstadial (extraordinarily high percentages exceeding 15% of the total pollen sum). Local pollen taxa, together with the lithological composition of deposits, revealed that there was a water body in the area during the periods of the Late Saalian/Early Eemian transition–Middle Eemian (the decline of the Tilia phase), the Herning stadial (MIS 5d), the early Brørup interstadial (MIS 5c), and the Rederstall stadial (MIS 5b). Between these time-intervals a poor and/or rich fen and/or bog functioned. [Copyright &y& Elsevier]

ABSTRACT Aim To determine relative effects of habitat type, climate and spatial pattern on species richness and composition of native and alien plant assemblages in central European cities. Location Central Europe, Belgium and the Netherlands. Methods The diversity of native and alien flora was analysed in 32 cities. In each city, plant species were recorded in seven 1-ha plots that represented seven urban habitat types with specific disturbance regimes. Plants were classified into native species, archaeophytes (introduced before ad 1500) and neophytes (introduced later). Two sets of explanatory variables were obtained for each city: climatic data and all-scale spatial variables generated by analysis of principal coordinates of neighbour matrices. For each group of species, the effect of habitat type, climate and spatial variables on variation in species composition was determined by variation partitioning. Responses of individual plant species to climatic variables were tested using a set of binomial regression models. Effects of climatic variables on the proportion of alien species were determined by linear regression. Results In all cities, 562 native plant species, 188 archaeophytes and 386 neophytes were recorded. Proportions of alien species varied among urban habitats. The proportion of native species decreased with increasing range and mean annual temperature, and increased with increasing precipitation. In contrast, proportions of archaeophytes and neophytes increased with mean annual temperature. However, spatial pattern explained a larger proportion of variation in species composition of the urban flora than climate. Archaeophytes were more uniformly distributed across the studied cities than the native species and neophytes. Urban habitats rich in native species also tended to be rich in archaeophytes and neophytes. Main conclusions Species richness and composition of central European urban floras are significantly affected by urban habitat types, climate and spatial pattern. Native species, archaeophytes and neophytes differ in their response to these factors. [ABSTRACT FROM AUTHOR]

Abstract: The Woodland Brown (Lopinga achine) is a characteristic flagship species for forests. Although it has experienced a dramatic decline, our knowledge concerning the reasons for the population loss is scarce. In this paper: (i) we analyze its habitat preferences on a regional scale in the Bavarian Alps; and (ii) we attempt to determine potential drivers of the decline on a national scale across Germany. Vegetation structure, microclimate and host-plant availability were the most crucial factors explaining habitat selection. Forests with a light canopy on south-facing slopes were the preferred woodland type in the study area. They had a medium-high and dense herbaceous layer rich in low-competitive sedges. Carex alba appeared to be the main host plant. Dense stands of C. alba are necessary to fulfill the eggs’ humidity requirements and to enable ease of access by the larvae. The preference for extraordinarily light forests on warm south-facing slopes most likely reflects a compensation for the cold mountain climate near the altitudinal range limit. Within Germany, L. achine populations have become extinct in regions with a mild climate, while most of the remaining colonies are restricted to areas with cold winters. However, the explanatory power of the model was very low. As the disappearance of the species coincides temporally with the abandonment of coppicing and wood pasture, we assume that the cessation of this management technique was the major driver of the range retraction. In most of the Central European habitats, long-term survival of L. achine strongly depends on suitable forest management. [Copyright &y& Elsevier]

Abstract: Sediment deposition in floodplains is an essential part of the sediment dynamics of a catchment. These sediment dynamics can vary largely on a Holocene time scale under the influence of driving forces such as land use and climatic variations. In this paper we review the Holocene floodplain sediment deposition history of rivers in West and Central Europe, with special attention to the influence of climate and land use variability. During the early Holocene (Preboreal to Atlantic Period), most floodplains were rather stable with limited floodplain aggradation. After this initial phase of relative stability, sedimentation rates increase during the Middle and Late Holocene, with often the most important deposition phase during the last 1000 to 2000 a. The start of the increase in sedimentation varies spatially, with an earlier start in the west (France, Germany) then in the east (Poland, Belarus, Ukraine), while there are also local differences between regions which are settled early (e.g. loess regions) compared to later settled regions. The sedimentation history of most floodplains can be linked to the local land use history, while influence of climatic variations on floodplain aggradation is often reported to be of minor importance. Processes related to bedload are often reported to be more influenced by climatic events. Relationships between the driving forces and the sediment history are mainly based on synchronicity, and there is seldom proof for a direct causal relationship. Future research should focus on a system-based approach, integrating the floodplain deposition in the entire sediment dynamics which includes also erosion, colluvial deposition and export. Main research questions that need further attention include integration of system-based concepts, like landscape connectivity and buffering effects, and also the assessment of the individual contribution of land use changes and climatologic variations on the sediment dynamics. Detailed sediment budget studies combined with modeling studies can make an important contribution to the understanding of floodplain sediment dynamics. [Copyright &y& Elsevier]

Taking the role of frames into account may significantly add to the tools that have been developed for communication and learning on complex risks and benefits. As part of a larger multidisciplinary study into climate-related forms of sense-making this paper explores which frames are used by the citizens of Western European countries and, in particular, the Netherlands. Three recent multi-national public opinion surveys were analysed to examine beliefs about climate change in the context of beliefs about energy technology and concerns about other environmental issues, such as natural disasters. It appeared that many citizens had only vague ideas about the energy situation and that these do not constitute an unequivocal frame for climate issues. In contrast, the results suggest that the long-lasting rainfall and severe floods in Central Europe have had a significant impact. Climate change was often framed in a way that articulates its associations with rain- and river-based problems. This result is extremely important for risk communication, because especially in the Netherlands with its vulnerable coastal zones climate change may produce many more consequences than rain- and river-based problems only [ABSTRACT FROM AUTHOR]

Differentiating natural climate change from anthropogenic forcing is a major challenge in the prediction of future climates. In this context, the investigation of interglacials provides valuable information on natural climate variability during periods that resemble the present. This paper shows that natural cyclic changes in winter climates affected central European environments during the last interglacial, i.e., the Eemian, 126–110 ka. As a result of the extraordinarily high counting sums performed at Eemian pollen samples, it was possible to reveal a robust presence--absence pattern of the insect-pollinated, and therefore in the pollen rain underrepresented, taxon Hedera. This plant is known to require the influence of oceanic winter climates, i.e., moist and mild, in northwest and central Europe. By analogy with recent findings from the North Atlantic's Holocene interglacial, the trigger of the Eemian climate variability may have been changes in solar activity, possibly amplified by changes in North Atlantic ocean currents and/or in the North Atlantic Oscillation. Our findings suggest natural cyclic changes to be a persistent feature of interglacial climates. [ABSTRACT FROM AUTHOR]

The article presents Central European perspective on why nationalism is not the right doctrine to combat climate change. Topics include nationalism the political doctrine that can help the world to deliver on the need to decrease greenhouse gas emissions; and ideas of ecological modernization that suggest to mitigate climate change efficiently through technological innovations and without reforms in the decision-making.

Central Europe has experienced a severe drought almost every April for the last 14 years consecutively, driven by record high temperatures, low flows, high evapotranspiration, and high soil moisture deficit. The dynamic of this recent and recurrent mid-spring dryness is not yet understood. Here we show that the period 2007–2020 was characterized by a reduction of ~50% of the usual April rainfall amount over large areas in central Europe. The precipitation deficit and the record high temperatures were triggered by a multiyear recurrent high-pressure system centered over the North Sea and northern Germany and a decline in the temperature gradient between the Arctic region and the mid-latitudes, which diverted the Atlantic storm tracks northward. From a long-term perspective, the precipitation, temperature, and soil moisture anomalies observed over the last 14 years have reached the highest amplitudes over the observational record. Our study provides an in-depth analysis of the hydroclimate extremes in central Europe over the last 140 years and their atmospheric drivers, enabling us to increase our dynamical understating of long-term dry periods, which is vital to enhance forecasting and mitigation of such events. [ABSTRACT FROM AUTHOR]

Climate change affects the distribution of many species, including Burgundy and Périgord truffles in central and southern Europe, respectively. The cultivation potential of these high-prized cash crops under future warming, however, remains highly uncertain. Here we perform a literature review to define the ecological requirements for the growth of both truffle species. This information is used to develop niche models, and to estimate their cultivation potential in the Czech Republic under current (2020) and future (2050) climate conditions. The Burgundy truffle is already highly suitable for cultivation on ~ 14% of agricultural land in the Czech Republic (8486 km2), whereas only ~ 8% of the warmest part of southern Moravia are currently characterised by a low suitability for Périgord truffles (6418 km2). Though rising temperatures under RCP8.5 will reduce the highly suitable cultivation areas by 7%, the 250 km2 (3%) expansion under low-emission scenarios will stimulate Burgundy truffles to benefit from future warming. Doubling the moderate and expanding the highly suitable land by 352 km2 in 2050, the overall cultivation potential for Périgord truffles will rise substantially. Our findings suggest that Burgundy and Périgord truffles could become important high-value crops for many regions in central Europe with alkaline soils. Although associated with uncertainty, long-term investments in truffle cultivation could generate a wide range of ecological and economic benefits. [ABSTRACT FROM AUTHOR]

Since the spring 2018, a large part of Europe has been in the midst of a record-setting drought. Using long-term observations, we demonstrate that the occurrence of the 2018–2019 (consecutive) summer drought is unprecedented in the last 250 years, and its combined impact on the growing season vegetation activities is stronger compared to the 2003 European drought. Using a suite of climate model simulation outputs, we underpin the role of anthropogenic warming on exacerbating the future risk of such a consecutive drought event. Under the highest Representative Concentration Pathway, (RCP 8.5), we notice a seven-fold increase in the occurrence of the consecutive droughts, with additional 40 ( ± 5 ) million ha of cultivated areas being affected by such droughts, during the second half of the twenty-first century. The occurrence is significantly reduced under low and medium scenarios (RCP 2.6 and RCP 4.5), suggesting that an effective mitigation strategy could aid in reducing the risk of future consecutive droughts. [ABSTRACT FROM AUTHOR]

Reconstructing long-term continental temperature change provides the required counterpart to age equivalent marine records and can reveal how terrestrial and marine temperatures were related during times of extreme climate change such as the Miocene Climatic Optimum (MCO) and the following Middle Miocene Climatic Transition (MMCT). Carbonate clumped isotope temperatures (T(Δ47)) from 17.5 to 14.0 Ma Central European paleosols (Molasse Basin, Switzerland) display a temperature pattern during the MCO that is similar to coeval marine temperature records. Maximum temperatures in the long-term soil T(Δ47) record (at 16.5 and 14.9 Ma) lag maximum ocean bottom water temperatures, lead global ice volume, and mark the initiation of minimum global ice volume phases. The suggested onset of the MMCT, deduced by a marked and rapid decline in Molasse Basin soil temperatures is coeval with cooling reported in high-latitudinal marine records. This is best explained by a change in the seasonal timing of soil carbonate formation that was likely driven by a modification of rainfall seasonality and thus by a major reorganization of mid-latitude atmospheric circulation across Central Europe. In particular, our data suggest a strong climate coupling between the North Atlantic and Central Europe already in the middle Miocene. [ABSTRACT FROM AUTHOR]

The article focuses on impact of socio-economic factors on environmental change and affecting of biodiversity and climate change by humans. Topics discussed include rapid transformation in Central and Eastern Europe (CEE) in terms of political changes and economic growth, political transformation is experienced by CEE countries towards free market and democracy and changes in ecosystem management will also be observed if the European Union (EU) is continuously accessed.

Due to global climate change and anthropogenic pressures on the landscape, one of the current geographical problems is retention of water in agricultural landscapes. One possibility to tackle this issue is the construction of artificial water bodies, which has historical traditions in the form of fishponds in Central European landscapes. Unfortunately, many such water bodies were transformed into arable lands during the 18th and 19th centuries. In this study, the identification and spatial distribution of these extinct water bodies is subject to examination, using place names in a GIS environment. Some 375 place names were selected from the official database of place names in the Czech Republic. This set of names was compared to current maps, as well as to old maps from the Habsburg monarchy from 1783-1880 (1st, 2nd and 3rd Military Survey). The map resources were used to find out if a place name was related to an extinct fishpond, and in which period the pond ceased to exist. Using spatial statistics, the existence of areas with a high concentration of place names referring to extinct ponds is demonstrated. It has also been established that areas linked to fishpond extinction in the same period now face more frequent droughts. Thus, the set of place names can be used to identify not only extinct water bodies, but also to serve as being potentially useful in other analyses using GIS, as well as in the public sphere (reclamation). [ABSTRACT FROM AUTHOR]

Stakeholders, researchers and designers apply different overheating metrics because they follow different comfort theories or comply with different regulations and standards. As a result, there is no common ground for generalization, intercomparison and final concordance of their conclusions. Correlation of indices would simplify the analysis being conducted during the design (optimization process) or operational (comfort assessment) phase of buildings. This research compares and statistically correlates results of seven widely used long-term overheating indices on four ‘free-running’ representative dwellings and characteristic climatic conditions of central Europe (Denmark, United Kingdom, Austria and France). Different renovation steps and passive cooling strategies were applied on these case studies creating 66 variants for comfort assessment. The analyses were conducted with the use of a dynamic energy performance engine and widely accepted calculation methods and statistical tools. The statistical analyses show that dynamic indices originate from the same adaptive comfort theory directly related with each other. In addition, it is possible to create general and widely applied relationships between static overheating indices independently of the case study and climatic condition. [ABSTRACT FROM AUTHOR]

Understanding the genecology of forest trees is critical for gene conservation, for predicting the effects of climate change and climate change adaptation, and for successful reforestation. Although common genecological patterns have emerged, species-specific details are also important. Which species are most vulnerable to climate change? Which are the most important adaptive traits and environmental drivers of natural selection? Even though species have been classified as adaptive specialists vs. adaptive generalists, large-scale studies comparing different species in the same experiment are rare. We studied the genecology of Norway spruce ( Picea abies) and silver fir ( Abies alba), two co-occurring but ecologically distinct European conifers in Central Europe. For each species, we collected seed from more than 90 populations across Switzerland, established a seedling common-garden test, and developed genecological models that associate population variation in seedling growth and phenology to climate, soil properties, and site water balance. Population differentiation and associations between seedling traits and environmental variables were much stronger for Norway spruce than for silver fir, and stronger for seedling height growth than for bud phenology. In Norway spruce, height growth and second flushing were strongly associated with temperature and elevation, with seedlings from the lowlands being taller and more prone to second flush than seedlings from the Alps. In silver fir, height growth was more weakly associated with temperature and elevation, but also associated with water availability. Soil characteristics explained little population variation in both species. We conclude that Norway spruce has become an adaptive specialist because trade-offs between rapid juvenile growth and frost avoidance have subjected it to strong diversifying natural selection based on temperature. In contrast, because silver fir has a more conservative growth habit, it has evolved to become an adaptive generalist. This study demonstrates that co-occurring tree species can develop very different adaptive strategies under identical environmental conditions, and suggests that Norway spruce might be more vulnerable to future maladaptation due to rapid climate change than silver fir. [ABSTRACT FROM AUTHOR]

The regional climate model RegCM4.2 was coupled to the chemistry transport model CAMx, including two-way interactions, to evaluate the regional impact of urban emission from central European cities on climate for present-day (2001-2010) and future (2046-2055) periods, and for the future one only emission changes are considered. Short-lived non-CO2 emissions are considered and, for the future impact, only the emission changes are accounted for (the climate is kept "fixed"). The urban impact on climate is calculated with the annihilation approach in which two experiments are performed: one with all emissions included and one without urban emissions. The radiative impacts of non-CO2 primary and secondary formed pollutants are considered, namely ozone (O3), sulfates (PSO4), nitrates (PNO3), primary organic aerosol and primary elementary carbon (POA and PEC). The validation of the modelling system is limited to key climate parameters, near-surface temperature and precipitation. It shows that the model, in general, underestimates temperature and overestimates precipitation. We attribute this behaviour to an excess of cloudiness/water vapour present in the model atmosphere as a consequence of overpredicted evaporation from the surface. The impact on climate is characterised by statistically significant cooling of up to -0.02 and -0.04K in winter (DJF) and summer (JJA), mainly over cities.We found that the main contributors to the cooling are the direct and indirect effects of the aerosols, while the ozone titration, calculated especially for DJF, plays rather a minor role. In accordance with the vertical extent of the urban-emission-induced aerosol perturbation, cooling dominates the first few model layers up to about 150m in DJF and 1000m in JJA. We found a clear diurnal cycle of the radiative impacts with maximum cooling just after noon (JJA) or later in afternoon (DJF). Furthermore, statistically significant decreases of surface radiation are modelled in accordance with the temperature decrease. The impact on the boundary layer height is small but statistically significant and decreases by 1 and 6m in DJF and JJA respectively. We did not find any statistically significant impact on precipitation and wind speed. Regarding future emissions, the impacts are, in general, smaller as a consequence of smaller emissions, resulting in smaller urban-induced chemical perturbations. In overall, the study suggest that the non-CO2 emissions play rather a minor role in modulating regional climate over central Europe. Much more important is the direct climate impact of urban surfaces via the urban canopy meteorological effects as we showed earlier. [ABSTRACT FROM AUTHOR]

Recommendations on suitable seed sources for reforestation are usually model based and include uncertainties arising from model assumptions, parameter estimation, and future climate scenarios. Due to the long-lived nature of forests, such uncertainties need to be considered when developing guidance for managers and policy makers. We evaluate the uncertainties and apply our recently developed genetically based models, Universal Response Functions (URFs) in Austria and Germany. The URFs predict growth performance (dominant height and basal area at age 24) of Douglas-fir ( Pseudotsuga menziesii [Mirbel] Franco) populations, as a function of both environmental and genetic factors. We evaluated the URFs by comparing the predicted height growth performances with observations from independent provenance trial data across Europe. Also, the sensitivity of the URF variables and the overall model uncertainty were estimated and compared to the uncertainty due to climate change projections. Model evaluation suggests that the URFs perform better in Central and Southeastern Europe compared to maritime Western Europe. Summer drought and mean annual temperature of planting sites were the most sensitive variables of the models, whereas the mean annual temperature of seed origin was the least sensitive. Model uncertainty increased with mean annual temperature of the planting site. Uncertainty due to projected future climate was found to be higher than the model uncertainty. The URFs predicted that provenance regions of southwest Germany and southeast Austria below 1500 m altitude will be suitable, whereas Pannonian east of Austria will become less suitable for growing Douglas-fir in future. Current seed stands in North America providing planting materials for Europe under the legal framework of the Organization for Economic Cooperation and Development shall continue to provide the most suitable seed material also in the future. [ABSTRACT FROM AUTHOR]

Blocking anticyclonic circulations from Europe are provoking climatic episodes responsible for discomfort, human and financial loses. During the summer, these episodes are known for prolonged droughts and maximum temperatures often exceeding 35 °C to 40 °C. In the cold season, the rainfalls are close to 0 while the daily minimum temperatures are low under the average period. For this study, we used a synoptic classification which is available especially for Central Europe but works similarly for Romanian territory too. We aim to follow what kind of climatic conditions these circulations are producing in Romania during their presence in Europe. ECA&D daily gridded climatic dataset was used in this study. The study period lasts from 1961 to 2012. We used the minimum and maximum daily temperatures as well the rainfall quantities recorded. Since the output volume of data was too high, we aggregated the results into yearly multiseasonal average. In order to classify the synoptic patterns as blocking anticyclones, we used two synoptic situations from Hess-Brezowsky defined as Anticyclone High Central (HM) and High British Isles (HB). We calculated the thermic anomalies as well the rainfall quantities recorded in Romania during the presence of these circulations in central Europe. The results shows a perspective over the synoptic conditions in Romania during the presence of the above mentioned synoptic types in Central Europe. [ABSTRACT FROM AUTHOR]

ABSTRACT The research objectives were to describe heat waves (HWs) in Central Europe and define the synoptic situations that cause their occurrence. In this article, a hot day was defined as a day when the maximum temperature was above the 95th annual percentile and an HW was considered a sequence of at least five hot days. In the analysed multi-year period and study area, 11 HWs were observed in the north and 51 HWs were observed in the south. The occurrence of HWs was mainly connected with positive anomalies of sea level pressure and with the 500 hPa level, which shows the presence of high-pressure systems. HWs were also accompanied by positive T850 and precipitable water ( PW) anomalies. [ABSTRACT FROM AUTHOR]

Climate change is among the most important global threats to biodiversity and mountain areas are supposed to be under especially high pressure. Although recent modelling studies suggest considerable future range contractions of montane species accompanied with increased extinction risk, data allowing to test actual population consequences of the observed climate changes and identifying traits associated to their adverse impacts are very scarce. To fill this knowledge gap, we estimated long-term population trends of montane birds from 1984 to 2011 in a central European mountain range, the Giant Mountains (Krkonoše), where significant warming occurred over this period. We then related the population trends to several species' traits related to the climate change effects. We found that the species breeding in various habitats at higher altitudes had more negative trends than species breeding at lower altitudes. We also found that the species moved upwards as a response to warming climate, and these altitudinal range shifts were associated with more positive population trends at lower altitudes than at higher altitudes. Moreover, long-distance migrants declined more than residents or species migrating for shorter distances. Taken together, these results indicate that the climate change, besides other possible environmental changes, already influences populations of montane birds with particularly adverse impacts on high-altitude species such as water pipit (Anthus spinoletta). It is evident that the alpine species, predicted to undergo serious climatically induced range contractions due to warming climate in the future, already started moving along this trajectory. [ABSTRACT FROM AUTHOR]

Climate change is expected to become an important driver influencing biodiversity. To protect biological diversity in the long term, nature conservationists must include potential climate change impacts in their management decisions. In order to incorporate effective climate change adaption strategies in the management of protected areas, potential threats of climate change need to be identified. In this study, climate model projections have been evaluated to derive information about the future exposure of nature parks to climate change. Indicators reflecting climate boundary conditions were selected in a cooperative process, considering both scientifically reliable climate scenario analysis and the requirements of park managers. The evaluation exhibits large uncertainties depending on the indicator. While for temperature, a warming trend is projected for all the regions, future projections for precipitation show the largest inter-model uncertainties. The Climatic Water Balance reflects the potential water availability and aids clarification to stakeholders, as it incorporates the temperature trend. The analysis robustly indicates a prolongation for the climatic growing season. The main challenges related to climate model information for decision-making are the uncertainties, different scales of climate and ecosystem processes and the finding of a common communication level for knowledge transfer. The results are useful for climate-influenced decision-making and provide one part of evidence for making adaptation decisions. [ABSTRACT FROM AUTHOR]

Identifying populations within tree species potentially adapted to future climatic conditions is an important requirement for reforestation and assisted migration programmes. Such populations can be identified either by empirical response functions based on correlations of quantitative traits with climate variables or by climate envelope models that compare the climate of seed sources and potential growing areas. In the present study, we analyzed the intraspecific variation in climate growth response of Douglas-fir planted within the non-analogous climate conditions of Central and continental Europe. With data from 50 common garden trials, we developed Universal Response Functions (URF) for tree height and mean basal area and compared the growth performance of the selected best performing populations with that of populations identified through a climate envelope approach. Climate variables of the trial location were found to be stronger predictors of growth performance than climate variables of the population origin. Although the precipitation regime of the population sources varied strongly none of the precipitation related climate variables of population origin was found to be significant within the models. Overall, the URFs explained more than 88% of variation in growth performance. Populations identified by the URF models originate from western Cascades and coastal areas of Washington and Oregon and show significantly higher growth performance than populations identified by the climate envelope approach under both current and climate change scenarios. The URFs predict decreasing growth performance at low and middle elevations of the case study area, but increasing growth performance on high elevation sites. Our analysis suggests that population recommendations based on empirical approaches should be preferred and population selections by climate envelope models without considering climatic constrains of growth performance should be carefully appraised before transferring populations to planting locations with novel or dissimilar climate. [ABSTRACT FROM AUTHOR]

Palaeolimnological reconstruction of the aquatic environment in Lake Komořany, based on sedimentology, geochemistry, and diatom and macrofossil analyses in the littoral part of the basin, reflects the mid-Holocene history of the profile from its origin c. 9100 cal. a BP to its final transformation into an alder carr c. 4100 cal. a BP. The existence of the littoral zone can be best explained by increased precipitation during the studied interval. A stable diatom community, diatom-inferred total phosphorus (50-80 μg L−1) and pH (~7.6), along with stable concentrations of elements associated with changes in its watershed indicate a long-lasting, balanced aquatic environment with no major shifts attributable to external factors, including climate change. From c. 4700 cal. BP, there started a transition to terrestrial conditions, caused by either natural infilling processes or decreased precipitation. Alternation of remarkable dry/wet phases was not detected, in contrast to numerous analogous central European and supraregional records. Potential human impact was revealed through increases of Corylus and Populus pollen in the Neolithic. These anthropogenic changes in the lake surroundings had no detectable influence on the lacustrine environment. The gathered data suggest undramatic, balanced mid-Holocene environmental and climatic settings for this central European locality, in direct contrast to numerous analogous studies from the region emphasizing fluctuations and shifts found in the sediment record. [ABSTRACT FROM AUTHOR]

Minimum and maximum temperature in two regional climate models and five statistical downscaling models are validated according to a unified set of criteria that have a potential relevance for impact assessments: persistence (temporal autocorrelations), spatial autocorrelations, extreme quantiles, skewness, kurtosis, and the degree of fit to observed data on both short and long times scales. The validation is conducted on two dense grids in central Europe as follows: (1) a station network and (2) a grid with a resolution of 10 km. The gridded dataset is not contaminated by artifacts of the interpolation procedure; therefore, we claim that using a gridded dataset as a validation base is a valid approach. The fit to observations in short time scales is equally good for the statistical downscaling (SDS) models and regional climate models (RCMs) in winter, while it is much better for the SDS models in summer. The reproduction of variability on long time scales, expressed as linear trends, is similarly successful by both SDS models and RCMs. Results for other criteria suggest that there is no justification for preferring dynamical models at the expense of statistical models-and vice versa. The non-linear SDS models do not outperform the linear ones. [ABSTRACT FROM AUTHOR]

Aim Although numerous studies have reported advanced Northern Hemisphere spring phenology since the 1980s, recent studies based on remote sensing have reported a reversal or deceleration of this trend. This study aimed (1) to fully understand recent spring phenology shifts using both in situ observations and satellite-based normalized difference vegetation index ( NDVI) datasets, and (2) to test whether the NDVI methods capture the trends observed in situ. Location Western Central Europe. Methods Temporal spring phenology trends (leaf unfolding dates) were examined using 1,001,678 in situ observations of 31 plant species at 3984 stations, as well as NDVI-based start-of-season dates, obtained using five different methods, across the pixels that included the phenology stations. Results In situ and NDVI observations both indicated that spring phenology significantly advanced during the period 1982-2011 at an average rate of −0.45 days yr−1. This trend was not uniform across the period and significantly weakened over the period 2000-2011. Furthermore, opposite trends were found between in situ and NDVI observations over the period 2000-2011. Averaged over all species, the in situ observations indicated a slower but still advancing trend for leaf unfolding, whereas the NDVI series showed a delayed spring phenology. Main conclusions The recent trend reversal in the advancement of spring phenology in western Central Europe is likely to be related to the response of early spring species to the cooling trend in late winter. In contrast, late spring species continued to exhibit advanced leaf unfolding, which is consistent with the warming trend during spring months. Because remote sensing does not distinguish between species, the signal of growing-season onset may only reflect the phenological dynamics of these earliest species in the pixel, even though most species still exhibit advancing trends. [ABSTRACT FROM AUTHOR]

One of the ways to assess the impacts of climate change on plants is analysing their long-term phenological data. We studied phenological records of 18 common tree species and their 8 phenological phases, spanning 65 years (1946−2010) and covering the area of the Czech Republic. For each species and phenophase, we assessed the changes in its annual means (for detecting shifts in the timing of the event) and standard deviations (for detecting changes in duration of the phenophases). The prevailing pattern across tree species was that since around the year 1976, there has been a consistent advancement of the onset of spring phenophases (leaf unfolding and flowering) and subsequent acceleration of fruit ripening, and a delay of autumn phenophases (leaf colouring and leaf falling). The most considerable shifts in the timing of spring phenophases were displayed by early-successional short-lived tree species. The most pronounced temporal shifts were found for the beginning of seed ripening in conifers with an advancement in this phenophase of up to 2.2 days year in Scots Pine ( Pinus sylvestris). With regards to the change in duration of the phenophases, no consistent patterns were revealed. The growing season has extended on average by 23.8 days during the last 35 years. The most considerable prolongation was found in Pedunculate Oak ( Quercus robur): 31.6 days (1976−2010). Extended growing season lengths do have the potential to increase growth and seed productivity, but unequal shifts among species might alter competitive relationships within ecosystems. [ABSTRACT FROM AUTHOR]

Facilitation, reduced competition or increased competition can arise in mixed stands and become essential to the performance of these stands when compared to pure stands. Facilitation and over-yielding are widely held to prevail on poor sites, whereas neutral interactions or competition, leading to under-yielding of mixed versus pure stands, can occur on fertile sites. While previous studies have focused on the spatial variation of mixing effects, we examine the temporal variation of facilitation and competition and its effect on growth. The study is based on tree ring measurement on cores from increment borings from 559 trees of Norway spruce ( Picea abies [ L.] Karst.), European beech ( Fagus sylvatica [ L.]) and sessile oak ( Quercus petraea ( Matt.) Liebl.) in southern Germany, half of which were in pure stands and half in adjacent mixed stands. Mean basal area growth indices were calculated from tree ring measurements for pure and mixed stands for every species and site. The temporal variation, with positive correlations between species-specific growth indices during periods of low growth and neutral or negative correlations during periods of high growth, is more distinct in mixed than in neighbouring pure stands. We provide evidence that years with low growth trigger over-yielding of trees in mixed as opposed to pure stands, while years with high growth lead to under-yielding. We discuss the relevance of the results in terms of advancing our understanding and modelling of mixed stands, extension of the stress gradient hypothesis, and the performance of mixed versus pure stands in the face of climate change. [ABSTRACT FROM AUTHOR]

The study deals with changes in large-scale atmospheric circulation (represented by circulation types) and associated surface air temperatures as projected in an ensemble of regional climate models (RCMs) from the ENSEMBLES project. We examine changes of circulation type frequencies and means of daily maximum and minimum temperatures within circulation types in individual seasons for two time slices of transient runs under the SRES A1B scenario (2021–2050 and 2071–2100) with respect to the control period (1961–1990). To study the influence of driving data, simulations of the driving general circulation models (GCMs) also are evaluated. We find that all models project changes of atmospheric circulation that are statistically significant for both future time slices. The models tend to project strengthening of the westerly circulation in winter and its weakening in summer. We show that increases of daily maximum and minimum temperatures in all seasons differ for individual circulation types. There are, however, only few features of the projected changes in the future circulation–temperature links that are common among the models, in particular relatively smaller warming for westerly types. Only in winter, projected changes in circulation types tend to contribute to the projected overall warming. This effect is negligible and mostly opposite in the other seasons. We also detect a strong influence of driving data on RCMs’ simulation of atmospheric circulation and temperature changes. [ABSTRACT FROM AUTHOR]

Tourism destinations often require information about climate to assess their climate potential. This can be performed in terms of mean conditions of relevant climatological parameters. For a user-friendly analysis and visualization of climate data relevant for tourism application in Luxembourg, information is prepared based on the facets of climate in tourism. Information on thermal comfort/stress conditions as well as aesthetical and physical parameters is considered. In the present study, relevant and sensible factors were identified and presented. Therefore, physiologically equivalent temperature, precipitation patterns and the Climate-Tourism/Transfer-Information-Scheme are applied. In addition, extreme events relevant for heat stress are analysed based on existing data sets (i.e. heat waves of 2010). Expected climatic conditions for the future are investigated using the projections of two different regional climate models. The results concerning climate change conditions reveal increasing heat stress and sultriness but decreasing cold stress. This information is the basis for an adequate assessment to provide relevant information for different environmental planning issues as well as for the growing tourism sector of Luxembourg. [ABSTRACT FROM AUTHOR]

Climate change as projected for Central Europe will lead to prolonged periods of summer drought and enhanced air temperature. Thus, forest management practices are required to take into account how species performance is adapted to cope with these climate changes. Oak trees may play a major role in future forests because of their relative drought-tolerance compared with other species like beech. Therefore, this study investigated the stress responses (i.e., anti-oxidants, free amino acids) in the leaves of three widely distributed oak species in Central Europe (i.e., Quercus robur L., Q. petraea [Matt.] Libel., Q. pubescens Willd.) to drought, air warming and the combination of drought plus air warming under controlled conditions after periods of spring drought, a short rewetting and summer drought. We quantified foliar levels of thiols, ascorbate, and free amino compounds in Q robur, Q. petraea and Q. pubescens. Our study showed that oak saplings had increased levels of γ-glutamylcysteine and total glutathione and proline with drought and air warming. Foliar ascorbate, glutathione disulfide and dehydroascorbic acid levels were not affected. The comparison of stress responses to drought and/or air warming between the three species showed higher foliar thiol levels in Q. robur and Q. pubescens compared with Q. petraea. For total and reduced ascorbic acid and γ-aminobutyric acid, the highest levels were found in Q. robur. In conclusion, our study showed that foliar anti-oxidant and free amino acid levels were significantly affected by drought plus air warming; however, this effect was species-dependent with the drought-tolerant species of Q. pubescens having the highest reactive oxygen species scavenging capacity among three tested oak species. Furthermore, stress responses as shown by increased levels of foliar anti-oxidants and free amino acids differ between calcareous and acidic soil indicating that the capacities of anti-oxidative defense and osmotic stress adjustment developed better on calcareous compared with acidic soil; however, this effect was metabolite- as well as species-specific. [ABSTRACT FROM PUBLISHER]

Climate data is used in many practical applications including energy demand estimations for heating and cooling, agricultural applications, risk assessment, and many more. The required climate data is only available if meteorological observations exist at a given location. In this study, the possibility of replacing long observational records with a few years of numerical weather forecast data is investigated for practical applications requiring temperature data. Observational data from 1980-2010, measured at 700 weather stations in Central Europe are used together with model forecasts of the years 2008-2010. Depending on the station, forecast data capture 90-110% of the standard deviation observed for daily mean and maximum temperatures and slightly less for minimum temperature. Heating and cooling degree days can be estimated with an error of 5-15% in climates where they have a relevance. Based on model data, maps of heating and cooling degree days are computed and the regional uncertainties are quantified using the observational data. The results suggest that numerical weather forecast data can be used for certain practical applications, either as a surrogate of observational data or for quite reliable estimates in locations with no observations. [ABSTRACT FROM AUTHOR]

Global climate change is expected to increase annual temperatures and decrease summer precipitation in Central Europe. Little is known of how forests respond to the interaction of these climate factors and if their responses depend on soil conditions. In a 3-year lysimeter experiment, we investigated the growth response of young mixed oak stands, on either acidic or calcareous soil, to soil water regime, air-warming and drought treatments corresponding to an intermediate climate change scenario. The air-warming and drought treatments were applied separately as well as in combination. The air-warming treatment had no effect on soil water availability, evapotranspiration or stand biomass. Decreased evapotranspiration from the drought-exposed stands led to significantly higher air and soil temperatures, which were attributed to impaired transpirational cooling. Water limitation significantly reduced the stand foliage, shoot and root biomass as droughts were severe, as shown in low leaf water potentials. Additional air warming did not enhance the drought effects on evapotranspiration and biomass, although more negative leaf water potentials were observed. After re-watering, evapotranspiration increased within a few days to pre-drought levels. Stands not subjected to the drought treatment produced significantly less biomass on the calcareous soil than on the acidic soil, probably due to P or Mn limitation. There was no difference in biomass and water regime between the two soils under drought conditions, indicating that nutrient availability was governed by water availability under these conditions. The results demonstrate that young oak stands can cope with severe drought and therefore can be considered for future forestry. [ABSTRACT FROM AUTHOR]

Climate-tolerant tree species and/or provenances have to be selected to ensure the high productivity of managed forests in Central Europe under the prognosticated climate changes. For this purpose, we studied the responses of saplings from three oak species ( i.e. Quercus robur, Q. petraea and Q. pubescens) and provenances of different climatic origin ( i.e. low or high rainfall, low or high temperature habitats) with regard to leaf nitrogen (N) composition as a measure of N nutrition. Saplings were grown in model ecosystems on either calcareous or acidic soil and subjected to one of four treatments (control, drought, air warming or a combination of drought and air warming). Across species, oak N metabolism responded to the influence of drought and/or air warming with an increase in leaf amino acid N concentration at the expense of structural N. Moreover, provenances or species from drier habitats were more tolerant to the climate conditions applied, as indicated by an increase in amino acid N (comparing species) or soluble protein N (comparing provenances within a species). Furthermore, amino acid N concentrations of oak leaves were significantly higher on calcareous compared to acidic soil. From these results, it can be concluded that seeds from provenances or species originating from drier habitats and - if available - from calcareous soil types may provide a superior seed source for future forest establishment. [ABSTRACT FROM AUTHOR]

Being tolerant to heat and drought, oaks are promising candidates for future forestry in view of climate change in Central Europe. Air warming is expected to increase, and drought decrease soil N availability and thus N supply to trees. Here, we conducted a model ecosystem experiment, in which mixed stands of young oaks ( Quercus robur, Q. petraea and Q. pubescens) were grown on two different soils and subjected to four climate treatments during three growing seasons: air warming by 1-2 °C, drought periods (average precipitation reduction of 43-60%), a combination of these two treatments, and a control. In contrast to our hypotheses, neither air warming nor drought significantly affected N availability, whereas total amounts, vertical distribution and availability of soil N showed substantial differences between the two soils. While air warming had no effect on tree growth and N accumulation, the drought treatment reduced tree growth and increased, or tended to increase, N accumulation in the reduced biomass, indicating that growth was not limited by N. Furthermore, 15 N-labelling revealed that this accumulation was associated with an increased uptake of nitrate. On the basis of our results, climate change effects on N dynamics are expected to be less important in oak stands than reduced soil water availability. [ABSTRACT FROM AUTHOR]