European beech dieback after premature leaf senescence during the 2018 drought in northern Switzerland

Plant Biology, Год журнала: 2022, Номер 24(7), С. 1132 - 1145

Опубликована: Сен. 14, 2022

During the particularly severe hot summer drought in 2018, widespread premature leaf senescence was observed several broadleaved tree species Central Europe, European beech (Fagus sylvatica L.). For beech, it is yet unknown whether evoked a decline towards mortality or trees can recover longer term. In this study, we monitored crown dieback, and secondary damage symptoms 963 initially live that exhibited either normal 2018 three regions northern Switzerland from to 2021. We related multiple climate- stand-related parameters. Cumulative continuously increased up 7.2% 1.3% 2021 for with respectively. Mean dieback surviving peaked at 29.2% 2020 8.1% 2019 senescence, Thereafter, showed first signs of recovery. Crown more pronounced recovery slower growing on drier sites, larger trees. The presence bleeding cankers 24.6% 10.7% bark beetle holes 22.8% 14.8% Both occurred frequently had higher proportions and/or 2018. Our findings demonstrate context-specific differences reflecting importance regional local climate soil conditions. Adapting management increase forest resilience gaining importance, given expected further dry sites Switzerland.

Язык: Английский

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Distinct Responses of European Beech (Fagus sylvatica L.) to Drought Intensity and Length—A Review of the Impacts of the 2003 and 2018–2019 Drought Events in Central Europe

Forests, Год журнала: 2023, Номер 14(2), С. 248 - 248

Опубликована: Янв. 28, 2023

A combined severe heatwave and drought, starting in 2018 lasting for several months, restarted the discussion on resistance of European beech to climatic changes, with growth reductions, early leaf senescence, browning, diebacks reported across Central Europe. These responses may result long-term impacts such as reduced vitality beech, especially under potential future drought periods. While 2003 caused crown damage defoliation a loss vitality, resulting insect fungal infestations subsequent dieback, was even more terms geographical scale, duration, intensity reports complete mortality were exacerbated some regions by consecutive 2019 secondary attacks from pathogens, well further vitality. Such enhanced exposure trees could push them beyond their hydraulic safety margins. Moreover, legacy effects due past droughts lead lower recovery over time, potentially leading tree death. In order better predict Europe, both short- influence post-drought should be explored, adaptive forest management strategies evaluated. synergistic or additive interactions biotic disturbances, require investigation. Long-term monitoring data facilitates investigations beech.

Язык: Английский

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Summer drought exposure, stand structure, and soil properties jointly control the growth of European beech along a steep precipitation gradient in northern Germany

Global Change Biology, Год журнала: 2022, Номер 29(3), С. 763 - 779

Опубликована: Ноя. 25, 2022

Abstract Increasing exposure to climate warming‐related drought and heat threatens forest vitality in many regions on earth, with the trees' vulnerability likely depending local climatic aridity, recent trends, edaphic conditions, acclimatization adaptation of populations. Studies exploring tree species' change often have a focus or model entire distribution range, which hampers separation drivers vulnerability. We compared radial growth trends sensitivity central populations widespread naturally dominant species Europe, European beech ( Fagus sylvatica ), at 30 sites across steep precipitation gradient (500–850 mm year −1 ) short length assess adaptive potential. Size‐standardized basal area increment remained more constant during period accelerated warming since early 1980s >360 growing season (April–September), while were negative <360 mm. Climatic June appeared as most influential factor affecting growth, stronger effect drier sites. A decadal decrease water balance summer was identified important leading decline, is amplified by higher stem densities. Inter‐annual variability has increased 1980s, generally sandier Similarly, within‐population synchrony balance. Our results caution against predicting trees solely from projections, soil properties emerged an modulating factor. conclude that facing decline centre its driven change‐related aridification.

Язык: Английский

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Nutrient regime modulates drought response patterns of three temperate tree species

The Science of The Total Environment, Год журнала: 2023, Номер 868, С. 161601 - 161601

Опубликована: Янв. 13, 2023

Against the backdrop of global change, intensity, duration, and frequency droughts are projected to increase threaten forest ecosystems worldwide. Tree responses drought complex likely vary among species, characteristics, site conditions. Here, we examined response patterns three major temperate tree s. fir (Abies alba), E. beech (Fagus sylvatica), N. spruce (Picea abies), along an ecological gradient in South - Central East part Germany that included a total 37 sites with varying climatic soil We relied on annual tree-ring data assess influence different characteristics (micro-) conditions components resilience detect associated temporal changes. Our study revealed nutrient regime, frequency, hydraulic previous subsequent years were main determinants responses, pronounced differences species. Specifically, found (a) higher was resistance for beech; (b) more favorable two preceding following increased determined recovery potential after extreme drought; (c) site's rather than micro-site water availability, trees growing balanced regime having capacity withstand stress; (d) experienced long-term decline resilience. results indicate under stress benefit from supply highlight relevance availability immediately droughts. Observed trends confirm is suffering persistent changes, while coping better. These findings might be especially relevant monitoring, scenario analyses, ecosystem management.

Язык: Английский

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Rapid beech decline under recurrent drought stress: Individual neighborhood structure and soil properties matter

Forest Ecology and Management, Год журнала: 2023, Номер 545, С. 121305 - 121305

Опубликована: Июль 29, 2023

During the summer of 2022, an acute drought once more afflicted central and southern Europe. This marked third episode (after 2015 2018) severe aridity in large parts Germany within last decade, leading to increased soil water depletion. Consequently, from July 2022 onward, European beech trees (Fagus sylvatica L.) exhibited early withering pronounced premature defoliation. Nevertheless, crown defoliation substantial variation among same forest stands, prompting questions regarding causal factors. In our study, we scrutinized twelve mature drought-impacted, beech-dominated stands northern Bavaria, arranged along a gradient different nutrient regime levels (base-rich, intermediate, base-poor), with co-occurring vital (≤40% defoliation) declining (≥60% trees. Within each stand, selected equal number trees, culminating total 332 target Dendrochronological patterns were analyzed identify potential timing growth separation between vitality classes. Moreover, used Bayesian modelling framework discern whether disparities tree hinged on competition, structure, small-scale differences plant-available capacity, spatial clustering competitors. We further explored factors influencing magnitude decline post-2018 how these modulated by site's regime. Our study unveiled that (i) low competition size diversity bolstered vitality; (ii) spatially aggregated; (iii) strikingly similar trajectories past, which underwent drastic shift following 2018, indicating for rapid under recurrent stress; (iv) capacity emerged as crucial determinant subsequent 2018; (v) was most at base-poor intermediate sites. findings underscore importance accommodating stand characteristics advocate silvicultural guidance towards reduced densities combination heterogenous structure mitigate dieback drought-prone stands.

Язык: Английский

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Daytime stomatal regulation in mature temperate trees prioritizes stem rehydration at night

New Phytologist, Год журнала: 2023, Номер 239(2), С. 533 - 546

Опубликована: Май 26, 2023

Trees remain sufficiently hydrated during drought by closing stomata and reducing canopy conductance (Gc ) in response to variations atmospheric water demand soil availability. Thresholds that control the reduction of Gc are proposed optimize hydraulic safety against carbon assimilation efficiency. However, link between ability stem tissues rehydrate at night remains unclear. We investigated whether species-specific responses aim prevent branch embolisms, or enable night-time rehydration, which is critical for turgor-dependent growth. For this, we used a unique combination concurrent dendrometer, sap flow leaf potential measurements collected branch-vulnerability curves six common European tree species. Species-specific was weakly related potentials 50% xylem conductivity lost (P50 ). Instead, found stronger relationship with rehydration. Species were less effective refilling stem-water storage as dries, appeared their architecture. Our findings highlight importance rehydration water-use regulation mature trees, likely relates maintenance adequate turgor. thus conclude must complement widely accepted safety-efficiency stomatal paradigm.

Язык: Английский

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The Future of European Beech in Northern Germany—Climate Change Vulnerability and Adaptation Potential

Forests, Год журнала: 2023, Номер 14(7), С. 1448 - 1448

Опубликована: Июль 14, 2023

Earth’s forests are increasingly exposed to climate risks through change-related drought and heat waves. Here, we review the vulnerability of European beech (Fagus sylvatica), most abundant tree species Central Europe’s temperate forests, its adaptation potential a hotter drier in northern Germany, close center species’ distribution range. About two-thirds studied show persistent negative growth trends their dominant trees since onset rapid warming early 1980s, driven primarily by long-term deterioration climatic water balance (CWB) summer and, locally, decrease June precipitation. Lower storage capacity soil increases sensitivity growth. Even though populations sub-regions reveal some acclimation (reduced stomatal conductance, turgor loss point reduction, higher C allocation roots), they more climate-vulnerable than at moister sites, visible larger decreases greater CWB mortality is still lower study region other parts Europe, our results identify forest regions with <350 mm growing-season precipitation as vulnerable recent conditions, which refers half region. With further aridification, Germany likely will become unfavorable for within next generation, suggests choosing many production alternative, drought- heat-resistant timber species.

Язык: Английский

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Water loss after stomatal closure: quantifying leaf minimum conductance and minimal water use in nine temperate European tree species during a severe drought

Tree Physiology, Год журнала: 2024, Номер 44(4)

Опубликована: Фев. 27, 2024

Abstract Residual canopy transpiration (Emin_canop) is a key physiological trait that determines trees’ survival time under drought after stomatal closure and trees have limited access to soil water. Emin_canop mainly depends on leaf minimum conductance (gmin) vapor pressure deficit. Here we determined the seasonal variation of gmin how related interspecies in cuticular traits for nine European tree species mature forest. In addition, species-specific temperature responses gmin. With this newly obtained insight, calculated one day at our research site during 2022 central hot drought. Our results show ambient temperatures ranged from 0.8 4.8 mmol m−2 s−1 across was stable most throughout growing season. The associated with traits. Additionally, exhibited strong increased, depending species, by factor two four range 25–50 °C. For studied site, single day, standardized size (stem basal area) 2.0 36.7 L m−2, non-standardized adult 0.3 5.3 L. also rapid increases hotter temperatures. suggest trees, need reasonable amounts water drought, even when stomates are fully closed. Species differences ultimately can, together other traits, affect ability keep its tissue hydrated likely contribute vulnerability.

Язык: Английский

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Inter-provenance variability and phenotypic plasticity of wood and leaf traits related to hydraulic safety and efficiency in seven European beech (Fagus sylvatica L.) provenances differing in yield

Annals of Forest Science, Год журнала: 2024, Номер 81(1)

Опубликована: Март 4, 2024

Abstract Key message Seven European beech provenances differing largely in growth performance were grown at two common garden sites Germany and Slovakia. The intra-specific variability of most traits was explained more by phenotypic plasticity than inter-provenance variability, efficiency-related showed a higher safety-related traits. Context To maintain climate-resilient future forests, replicated common-garden experiments are suited for developing assisted migration strategies key tree species. Aims We analysed the magnitude 12 functional ( Fagus sylvatica L.) whether climate place origin left an imprint. Moreover, we asked is unrelated to xylem safety what extent foliar, growth-related coordinated. Methods Terminal branches collected from 19-year-old 22-year-old trees seven planted Slovakia, respectively. Three hydraulic, three wood anatomical four foliar measured related variables. Results At sites, same pair highest lowest growth. Nevertheless, high degree observed, as all differed significantly between after accounting provenance effects, with hydraulic showing plasticity. There no evidence embolism resistance P 50 ) or carbon isotope signature (δ 13 C), proxy intrinsic water use efficiency (iWUE), both positively correlated lumen-to-sapwood area ratio vessel density. Conclusions Because lacking trade-off growth, highly productive can be selected without reducing drought tolerance branch xylem. However, only one element trees’ response, it may beneficial select other conservative adaptations such smaller lumen areas increasing small supported total leaf reduction transpiration.

Язык: Английский

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Xylem safety in relation to the stringency of plant water potential regulation of European beech, Norway spruce, and Douglas-fir trees during severe drought

Trees, Год журнала: 2024, Номер 38(3), С. 607 - 623

Опубликована: Март 23, 2024

Abstract Key message Norway spruce operates with larger hydraulic safety margins (HSM) than beech and Douglas-fir despite the known drought sensitivity of spruce, questioning a pivotal role HSM in tolerance. The exceptional 2018/2019 exposed Central Europe’s forests to severe stress, highlighting need better understand stomatal regulation strategies their relationship xylem under extreme drought. We studied diurnal, seasonal, inter-annual variation conductance ( g s ) leaf water potential Ψ Leaf co-occurring European F. sylvatica ), P. abies menziesii trees two summers related them traits characterizing resistance. In 2018, exhibited continuous decline from June September, as is characteristic for an anisohydric strategy, while closed stomata early reached least negative -values at end summer. showed low close P 12 (the pressure onset embolism) already July. Both conifers when approaching maintained -levels throughout summer, indicative isohydric regulation. 2019, all three species linear , but crossed contrast conifers. similar potentials turgor loss point (− 2.44 − 2.51 MPa) branch 50 (xylem 50% conductance; 3.3 3.8 MPa). Yet, operated smaller (HSM means: 0.79 0.77 (1.28 reduced size specific area 2019 increased Huber value. Our comparison during contradicts general assumption that operate HSMs angiosperm trees. Contrary expectation, appeared hydraulically less vulnerable Douglas-fir.

Язык: Английский

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