Csaba Mátyás

The altitude-for-latitude disparity in the range retractions of woody species

Increasing temperatures are driving rapid upward range shifts of species in mountains. An altitudinal range retreat of 10 m is predicted to translate into a approximately 10-km latitudinal retreat based on the rate at which temperatures decline with increasing altitude and latitude, yet reports of latitudinal range retractions are sparse. Here, we examine potential climatic, biological, anthropogenic and methodological explanations for this disparity. We argue that the lack of reported latitudinal range retractions stems more from a lack of research effort, compounded by methodological difficulties, rather than from their absence. Given the predicted negative impacts of increasing temperatures on wide areas of the latitudinal distributions of species, the investigation of range retractions should become a priority in biogeographical research.

Present and forecasted xeric climatic limits of beech and sessile oak distribution at low altitudes in Central Europe

Abstract• IntroductionXeric (trailing) forest range limits are particularly vulnerable to impacts of predicted climate change. Regional modelling studies contribute to the identification of potential local climatic threats and may support appropriate management strategies.• MethodsWe carried out bioclimatic distribution modelling of two climate-dependent, dominant tree species, beech and sessile oak, to determine the most influential climatic variables limiting their distributions and to predict their climate-induced range shifts over the twenty-first century in the forest-steppe biome transition zone of Hungary. To exclude confounding effects of edaphic conditions, only data of zonal sites were evaluated.• ResultsFor both species, temperature and precipitation conditions in late spring and summer appear as principal variables determining the distribution, with beech particularly affected by summer drought. Projections from the applied fine-scale analysis and modelling results indicate that climate change may lead to drastic reduction in macroclimatically suitable sites for both forest types.• ConclusionRegarding the stands in zonal position, 56–99% of present-day beech forests and 82–100% of sessile oak forests might be outside their present bioclimatic niche by 2050. Phenotypic plasticity, longevity, endurance of non-zonal stands and prudent human support may brighten these dire predictions. Nevertheless, an urgent adjustment of forest management and conservation strategies seems inevitable.

Forecasts needed for retreating forests.

As tree habitats shift towards the poles in response to climate change, we must study the neglected, trailing edges of forests, warns Csaba Matyas — they are economically and ecologically important.

Climate change increases the drought risk in Central European forests: What are the options for adaptation?

Abstract The paper presents information on the projected drought exposure of Central Europe, describes the anticipated dynamics of the regional forests, and identifies measures facilitating the adaptation of forests to climate change-induced drought risk. On the basis of an ensemble of climate change scenarios we expect substantial drying in southern Slovakia and Hungary, while such trends were found to be less pronounced for the Czech Republic and Austria. In response to these climate trajectories, a change in species composition towards a higher share of drought tolerant species as well as the use of drought resistant provenances are identified as paramount actions in forest adaptation in the region. Adaptation to aggravating climate change may need to use artificial regeneration to enrich local gene pools and increase the drought tolerance of stands. Increasing risks from pests, pathogens and other disturbances are expected as a result of more frequent and severe droughts, underlining the need to put a stronger focus on risk management principles rather than on indicators of productivity in silviculture and forest planning. A consolidation of disturbance monitoring systems and a broader use of pest dynamics and hazard rating models are paramount tools to facilitate this adaptation process in forest management. The effectiveness of all the suggested measures needs to be controlled by efficient forest monitoring systems, the consolidation of which seems to be a timely task. Systematic and long-term implementation of the presented measures should increase forest stability and resilience, and further secure the sustainable provision of ecosystem services under climate change. Abstrakt V článku sú prezentované informácie o očakávanom vývoji sucha v oblasti strednej Európy, je opísaná možná dynamika lesov v podmienkach zmeny klímy, a je vypracovaný systém opatrení umožňujúcich adaptáciu lesov na zmenu klímy. Na základe kolekcie scenárov zmeny klímy bol identifikovaný výrazný nárast intenzity sucha v oblastiach južného Slovenska a Maďarska, zatiaľ čo v oblasti Českej republiky a Rakúska bola zmena relatívne nevýrazná. S ohľadom na tento vývoj predstavuje úprava drevinového zloženia smerom k vyššiemu zastúpeniu sucho tolerujúcich drevín a širšiemu využívaniu proveniencií rezistentných voči suchu jedno zo základných adaptačných opatrení. V prípade výrazných zmien klímy narastá význam umelej obnovy, ktorá predstavuje nástroj na zlepšovanie druhovej a genetickej diverzity porastov a zvyšovanie ich tolerancie voči suchu. Narastajúci vplyv škodcov súvisiaci s rastúcim vplyvom sucha a ďalších abiotických činiteľov naznačuje potrebu orientovať pestovanie a hospodársku úpravu lesa viac na manažment rizík ako na maximalizáciu produkcie. Konsolidácia systémov monitoringu škodlivých činiteľov a širšie využívanie modelov dynamiky škodcov a hodnotenia rizík patria medzi ďalšie dôležité opatrenia podporujúce adaptáciu lesov na zmenu klímy. Všetky uvedené opatrenia musia byť podporené informáciami získanými na základe dlhodobého monitoringu lesa, ktorý však vyžaduje urýchlenú konsolidáciu. Systematická a dlhodobá realizácia prezentovaných opatrení podporí stabilitu a rezilienciu lesov a vytvorí predpoklady pre udržateľné poskytovanie ekosystémových služieb a funkcií v podmienkach zmeny klímy.

Forests in a water limited world under climate change

The debate on ecological and climatic benefits of planted forests at the sensitive dry edge of the closed forest belt (i.e. at the ‘xeric limits’) is still unresolved. Forests sequester atmospheric carbon dioxide, accumulate biomass, control water erosion and dust storms, reduce river sedimentation, and mitigate small floods. However, planting trees in areas previously dominated by grassland or cropland can dramatically alter the energy and water balances at multiple scales. The forest/grassland transition zone is especially vulnerable to projected drastic temperature and precipitation shifts and growing extremes due to its high ecohydrological sensitivity. We investigated some of the relevant aspects of the ecological and climatic role of forests and potential impacts of climate change at the dryland margins of the temperate-continental zone using case studies from China, the United States and SE Europe (Hungary). We found that, contrary to popular expectations, the effects of forest cover on regional climate might be limited and the influence of forestation on water resources might be negative. Planted forests generally reduce stream flow and lower groundwater table level because of higher water use than previous land cover types. Increased evaporation potential due to global warming and/or extreme drought events is likely to reduce areas that are appropriate for tree growth and forest establishment. Ecologically conscious forest management and forestation planning should be adjusted to the local, projected hydrologic and climatic conditions, and should also consider non-forest alternative land uses.

The incorporation of extreme drought events improves models for beech persistence at its distribution limit

ContextProjections of species distribution models under future climate are usually based on long-term averages. However, singular extreme drought events presumably contribute to the shaping of distribution limits at the retreating low-elevation xeric limits.MethodsThe objectives of this study were to set up a distribution model based on extreme drought events (EDM), which uses sanitary logging information as a proxy of vitality response of beech, and compare it with the results of classical species distribution models (SDMs).ResultsPredictions of the EDM for 2025 were in agreement with those of the SDM, but EDM predicted a more serious decline in all regions of Hungary towards the end of the century.ConclusionThese results suggest that the predicted increase in frequency and severity of drought events may further limit the distribution of beech in the future.

Regional characteristics of climate change altering effects of afforestation

Climatic effects of forest cover change have been investigated for Hungary. For the time period 2071–100 we have analyzed whether the climate change signal for summer precipitation and the probability of droughts can be reduced assuming maximal afforestation for the entire country (forests covering all vegetated areas). The biogeophysical effects of land cover change have been assessed using the results of an A1B IPCC-SRES emission scenario from REMO (regional climate model at the Max Planck Institute for Meteorology, Hamburg). The simulation results indicate that afforestation may reduce the projected climate change through higher evapotranspiration and precipitation as well as lower surface temperature for the entire summer period. The magnitude of the feedback of the forest cover increase on precipitation differs among regions. The strongest effects are visible in the northeastern part of the country. Here, half of the projected precipitation decrease can be relieved and the total number of drought events can be reduced, assuming maximal afforestation. Afforestation brings about the smallest climatic effect in the southwestern region, in the area that shows the strongest climate change. The results can help to identify areas where forest cover increase should most effectively support the alleviation of climate change effects.

Decline of genetic diversity of sessile oak at the retracting (xeric) limits

ContextGenetic diversity of sessile oak (Quercus petraea) populations in Hungary was assessed close to the retracting, low-elevation, low-latitude (xeric) distribution limits.ObjectiveWe aimed at tracing an assumed effect of climatic factors on genetic diversity, particularly at the southern, low elevation limits of distribution.MethodsGenetic diversity at isozyme-coding loci was analysed in populations, and related to the climate of the sites where the populations grow. A locus-wise analysis proved to be essential to follow responses.ResultsA climate-related cline was found at seven isoenzyme-coding gene loci. Declining allelic numbers and heterozygosity indicated lower diversity at warmer and drier sites. The majority of loci were responsive to precipitation factors, others to temperature. Genetic clustering was neither related to geographic distance nor to random or historic effects.ConclusionsThe results suggest that climatic stress may elicit a genetic diversity loss in populations, which may reduce their plasticity and adaptive potential. The selective pressure may override historic effects and gene flow. With respect to expected climate change, the correlation of diversity with some climatic factors gains specific importance. If supported by further investigations, the results might be utilised for reconsidering conservation strategies and rules for use of forest reproductive material.

Phenotypic trait variation measured on European genetic trials of Fagus sylvatica L

We present BeechCOSTe52; a database of European beech (Fagus sylvatica) phenotypic measurements for several traits related to fitness measured in genetic trials planted across Europe. The dataset was compiled and harmonized during the COST-Action E52 (2006–2010), and subsequently cross-validated to ensure consistency of measurement data among trials and provenances. Phenotypic traits (height, diameter at breast height, basal diameter, mortality, phenology of spring bud burst and autumn–leaf discoloration) were recorded in 38 trial sites where 217 provenances covering the entire distribution of European beech were established in two consecutive series (1993/95 and 1996/98). The recorded data refer to 862,095 measurements of the same trees aged from 2 to 15 years old over multiple years. This dataset captures the considerable genetic and phenotypic intra-specific variation present in European beech and should be of interest to researchers from several disciplines including quantitative genetics, ecology, biogeography, macroecology, adaptive management of forests and bioeconomy.