Climate sensitivity and drought seasonality determine post-drought growth recovery of Quercus petraea and Quercus robur in Europe

The Science of The Total Environment, Journal Year: 2021, Volume and Issue: 784, P. 147222 - 147222

Published: April 21, 2021

Recent studies have identified strong relationships between delayed recovery of tree growth after drought and mortality caused by subsequent droughts. These observations raise concerns about forest ecosystem services post-drought given the projected increase in frequency extremes. For quantifying impact extreme droughts on radial growth, we used a network tree-ring width data 1689 trees from 100 sites representing most distribution two tolerant, deciduous oak species (Quercus petraea Quercus robur). We first examined which climatic factors seasons control if there is any latitudinal, longitudinal or elevational trend. then quantified relative departure pre-drought during droughts, how fast were able to recover level. Our results showed that was more related precipitation water balance (precipitation minus potential evapotranspiration) than temperature. However, did not detect clear trends except decreasing influence summer Q. with latitude. Neither maintain level both rapid even compensation but displayed slow response spring where none fully growth-level over three years. Collectively, our indicate oaks are considered resilient also shown vulnerability when occurred especially at long-term significantly correlated factors. This improved understanding role seasonality climate sensitivity key better predict trajectories drier for Europe.

Language: Английский

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

Plant Biology, Journal Year: 2022, Volume and Issue: 24(7), P. 1132 - 1145

Published: Sept. 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.

Language: Английский

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Dominant role of soil moisture in mediating carbon and water fluxes in dryland ecosystems

Nature Geoscience, Journal Year: 2024, Volume and Issue: 17(1), P. 38 - 43

Published: Jan. 1, 2024

Language: Английский

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The role of height‐driven constraints and compensations on tree vulnerability to drought

New Phytologist, Journal Year: 2023, Volume and Issue: 239(6), P. 2083 - 2098

Published: July 23, 2023

Summary Frequent observations of higher mortality in larger trees than smaller ones during droughts have sparked an increasing interest size‐dependent drought‐induced mortality. However, the underlying physiological mechanisms are not well understood, with height‐associated hydraulic constraints often being implied as potential mechanism driving increased drought vulnerability. We performed a quantitative synthesis on how key traits that drive plant water and carbon economy change tree height within species assessed implications different compensations may interacting (hydraulic failure, starvation and/or biotic‐agent attacks) affecting vulnerability to drought. While xylem tension increases height, taller present range structural functional adjustments, including more efficient use transport greater uptake storage capacity, mitigate path‐length‐associated drop potential. These adaptations allow withstand episodic stress. Conclusive evidence for height‐dependent failure starvation, their coupling defence pest pathogen dynamics, is still lacking. Further research needed, particularly at intraspecific level, ascertain specific conditions thresholds above which hinders survival under

Language: Английский

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Revealing legacy effects of extreme droughts on tree growth of oaks across the Northern Hemisphere

The Science of The Total Environment, Journal Year: 2024, Volume and Issue: 926, P. 172049 - 172049

Published: March 27, 2024

Forests are undergoing increasing risks of drought-induced tree mortality. Species replacement patterns following mortality may have a significant impact on the global carbon cycle. Among major hardwoods, deciduous oaks (Quercus spp.) increasingly reported as replacing dying conifers across Northern Hemisphere. Yet, our knowledge growth responses these to drought is incomplete, especially regarding post-drought legacy effects. The objectives this study were determine occurrence, duration, and magnitude effects extreme droughts how that vary species, sites, characteristics. quantified by deviation observed from expected radial indices in period 1940–2016. We used stand-level chronologies 458 sites 21 oak species primarily Europe, north-eastern America, eastern Asia. found could last 1 5 years after more prolonged dry sites. Negative (i.e., lower than expected) prevalent repetitive effect was stronger Mediterranean Quercus faginea. Species-specific analyses revealed Q. petraea macrocarpa negatively affected while several mesic increased during years. Sites showing positive correlations winter temperature showed little no depression drought, whereas with correlation previous summer water balance decreased growth. This indicate although warming favors droughts, previous-year precipitation predispose trees current-year droughts. Our results massive role determining highlighted sensitivity climate, seasonality species-specific traits drive species.

Language: Английский

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Regional estimates of gross primary production applying the Process-Based Model 3D-CMCC-FEM vs. Remote-Sensing multiple datasets

European Journal of Remote Sensing, Journal Year: 2024, Volume and Issue: 57(1)

Published: Jan. 9, 2024

Process-based Forest Models (PBFMs) offer the possibility to capture important spatial and temporal patterns of carbon fluxes stocks in forests. Yet, their predictive capacity should be demonstrated not only at stand-level but also context broad heterogeneity. We apply a stand scale PBFM (3D-CMCC-FEM) spatially explicit manner 1 km resolution southern Italy. developed methodology initialize model that includes information derived from integration Remote Sensing (RS) National Inventory (NFI) data regional forest maps characterize structural features main species. Gross primary production (GPP) is simulated over 2005–2019 period capability simulating GPP evaluated both aggregated as species-level through multiple independent sources based on different nature RS-based products. show able reproduce most (~2800 km2) (32 years total) observed seasonal, annual interannual time scales, even species-level. These promising results open confindently applying 3D-CMCC-FEM investigate forests' behaviour under climate environmental variability large areas across highly variable ecological bio-geographical heterogeneity Mediterranean region.

Language: Английский

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The intraspecific variation of functional traits modulates drought resilience of European beech and pubescent oak

Journal of Ecology, Journal Year: 2021, Volume and Issue: 109(10), P. 3652 - 3669

Published: July 9, 2021

Abstract A higher frequency and intensity of droughts will impair forest productivity. Therefore, improving our understanding which factors enhance tree growth resilience against drought has become a crucial issue, but we lack information at the intraspecific level. In this study, investigate role played by climatic conditions characteristics in response to severe two deciduous Fagaceae species near their southern distribution limit: temperate European beech Fagus sylvatica Mediterranean pubescent oak Quercus pubescens . The study area is located Catalonia, NE Spain, where 149 trees were cored covering water availability gradient region. addition, size (diameter height) an ensemble stem, leaf hydraulic traits collected for each tree. Growth responses extreme during period 1980–2015 assessed using indicators based on residual basal increment series predicted model including growing season balance. Although resistance was unrelated intensity, improved recovery reduced legacy effects. Taller showed drought, could be explained relationship between variation height functional traits, such as nitrogen concentration, turgor loss point xylem embolism. For both species, with lower cavitation resistance, concentration tighter stomatal regulation (suggested less negative carbon isotope composition) displayed better performance after droughts. Both progressive decrease increase Synthesis This highlights relevance analysing involved balance improve variability within species.

Language: Английский

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Mediterranean old-growth forests exhibit resistance to climate warming

The Science of The Total Environment, Journal Year: 2021, Volume and Issue: 801, P. 149684 - 149684

Published: Aug. 16, 2021

Old-growth mountain forests represent an ideal setting for studying long-term impacts of climate change. We studied the few remnants old-growth located within Pollino massif (southern Italy) to evaluate how growth conspecific young and old trees responded investigated two conifer species (Abies alba Pinus leucodermis) hardwood (Fagus sylvatica Quercus cerris). sampled one stand per along altitudinal gradient, ranging from a drought-limited low-elevation forest cold-limited subalpine pine forest. used dendrochronological approach characterize dynamics (age > 120 years) versus < trees. Younger grew faster than their older conspecifics during juvenile stage, regardless species. Linear mixed effect models were quantify recent trends (1950-2015) responses Climate sensitivity, expressed as radial last three decades, partially differed between because high spring temperatures enhanced growth, whereas F. was negatively affected by warmer conditions. Furthermore, tree impacted summer drought in all sensitivity trees, with younger tending be more sensitive P. leucodermis A. alba, sensitive. In Q. cerris stands, limitation due not related age, suggesting symmetric water competition. found evidence fast-growth trend individuals compared that conspecifics. Notably, tended have relatively stable rates, showing remarkable resistance warming. These change should recognized when forecasting future sustainable management.

Language: Английский

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Retrospective analysis of wood anatomical traits and tree‐ring isotopes suggests site‐specific mechanisms triggering Araucaria araucana drought‐induced dieback

Global Change Biology, Journal Year: 2021, Volume and Issue: 27(24), P. 6394 - 6408

Published: Sept. 13, 2021

Abstract In 2010–2018, Northern Patagonia featured the longest severe drought of last millennium. This extreme dry spell triggered widespread growth decline and forest dieback. Nonetheless, roles played by two major mechanisms driving dieback, hydraulic failure carbon starvation, are still not clear understudied in this seasonally region. Here, for 1800–2017 period, we apply a retrospective analysis radial growth, wood anatomical traits (lumen area, cell‐wall thickness) δ 13 C 18 O stable isotopes to assess dieback causes iconic conifer Araucaria araucana . We selected three stands where declining (defoliated) nondeclining (not defoliated) trees coexisted along precipitation gradient from warm‐dry Coastal Range cool‐wet Andes. At all sites showed lower theoretical conductivity, suggesting long‐lasting process deterioration their water transport system compared nondeclining, coexisting trees. Wood evidenced that divergence between started at least seven decades before canopy drier stands, higher water‐use efficiency (WUE) throughout whole which attributed early stomatal closure, greater starvation risk consistent with thinner cell walls. wettest stand, found opposite pattern. reduction WUE coupled thicker walls suggested increased assimilation rates exposure drought‐induced failure. The values indicated different strategies gas exchange sites, likely consequence microsite conditions sources. Multiproxy, quantifications xylem tree‐ring provide robust tool identify forecast, or will show or, on contrary, withstand be more resilient future hotter droughts.

Language: Английский

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Long-term soil water limitation and previous tree vigor drive local variability of drought-induced crown dieback in Fagus sylvatica

The Science of The Total Environment, Journal Year: 2022, Volume and Issue: 851, P. 157926 - 157926

Published: Aug. 17, 2022

Ongoing climate warming is increasing evapotranspiration, a process that reduces plant-available water and aggravates the impact of extreme droughts during growing season. Such an exceptional hot drought occurred in Central Europe 2018 caused widespread defoliation mid-summer European beech (Fagus sylvatica L.) forests. Here, we recorded crown damage 2021 nine mature even-aged beech-dominated stands northwestern Switzerland along severity gradient (low, medium, high) analyzed tree-ring widths 21 trees per stand. We aimed at identifying predisposing factors responsible for differences across within such as tree growth characteristics (average rates year-to-year variability) site-level variables (mean canopy height, soil properties). found stand-level was strongly related to availability, inferred from height plant available storage capacity (AWC). Trees were shorter drier stands, had higher variability radial growth, showed sensitivity moisture conditions previous late summer than on soils with sufficient AWC, indicating these forests principally limited by availability. Within-stand variation post-drought corresponded rate size (diameter breast DBH), i.e., smaller slower-growing face more competition, associated increased after drought. These findings point vigor before (long-term relative rate) important driver stands. Our results suggest less likely be able cope future change-induced shallow retention capacity.

Language: Английский

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