Beyond source and sink control – toward an integrated approach to understand the carbon balance in plants

New Phytologist, Год журнала: 2024, Номер 242(3), С. 858 - 869

Опубликована: Фев. 20, 2024

Summary A conceptual understanding on how the vegetation's carbon (C) balance is determined by source activity and sink demand important to predict its C uptake sequestration potential now in future. We have gathered trajectories of photosynthesis growth as a function environmental conditions described literature compared them with current concepts control. There no clear evidence for pure or control balance, which contradicts recent hypotheses. Using model scenarios, we show legacy effects via structural functional traits antecedent can alter plant's balance. We, thus, combined concept short‐term source–sink coordination long‐term environmentally driven that dynamically acclimate over time. These acclimated feedback sensitivity thus change plant physiological responses conditions. postulate whole C‐coordination system primarily stomatal optimization avoid mismatch. Therefore, anticipate forest ecosystems under future climate will largely follow optimality principles water resources maximize long term.

Язык: 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, Год журнала: 2024, Номер 926, С. 172049 - 172049

Опубликована: Март 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.

Язык: Английский

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A protocol for high-quality sectioning for tree-ring anatomy

Frontiers in Plant Science, Год журнала: 2025, Номер 16

Опубликована: Фев. 26, 2025

Quantitative wood anatomy (QWA), which involves measuring cell anatomical characteristics commonly on dated tree rings, is becoming increasingly important within plant sciences and ecology. This approach particularly valuable for studies that require processing a large number of samples, such as those aimed at millennial-long climatic reconstructions. However, the field faces significant challenges, including absence publicly available comprehensive protocol efficiently uniformly producing high-quality thin sections QWA along tree-ring series. issue especially critical more brittle subfossil wood, in addition to fresh material from living trees. Our manuscript addresses these challenges by providing detailed digital images, specifically tailored long chronologies with an emphasis conifer wood. The includes step-by-step procedures sample preparation, sectioning, imaging, ensuring consistent results. By offering this well-tried-and-tested protocol, we aim facilitate reproducibility accuracy studies, ultimately advancing research field. It aims serve reference researchers laboratories engaged similar work, promoting standardized practices enhancing reliability data.

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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Mitigating drought stress in European beech and pedunculate oak: The role of competition reduction

Forest Ecosystems, Год журнала: 2025, Номер unknown, С. 100303 - 100303

Опубликована: Фев. 1, 2025

Язык: Английский

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Quantitative vessel mapping on increment cores: a critical comparison of image acquisition methods

Frontiers in Plant Science, Год журнала: 2025, Номер 16

Опубликована: Фев. 12, 2025

Introduction Quantitative wood anatomy is critical for establishing climate reconstruction proxies, understanding tree hydraulics, and quantifying carbon allocation. Its accuracy depends upon the image acquisition methods, which allows identification of number dimensions vessels, fibres, tracheids within a ring. Angiosperm analysed with variety different including surface pictures, anatomical micro-sections, or X-ray computed micro-tomography. Despite known advantages disadvantages, quantitative impact method selection on parameters not well understood. Methods In this study, we present systematic uncertainty analysis commonly used parameters. We four samples, representing range porosity, using micro-CT scans, micro-sections. Inter-annual patterns were compared between methods from five most frequently parameters, namely mean lumen area ( MLA ), vessel density VD vessels VN hydraulic diameter D h relative conductive RCA ). A novel sectorial approach was applied samples to obtain intra-annual profiles l specific theoretical conductivity K s ρ Results Our mapping revealed that values obtained are comparable across supporting use easily applicable picture ring-porous diffuse-porous species. While variability captured by species, ) overestimated due lack fibre detection. Discussion study highlights potential limitations extracting Moreover, standardized workflow assessing radial ring profiles. These findings encourage compilation all studies further research refine these ultimately enhancing accuracy, replication, spatial representation studies.

Язык: Английский

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When do plant hydraulics matter in terrestrial biosphere modelling?

Global Change Biology, Год журнала: 2023, Номер 30(1)

Опубликована: Ноя. 14, 2023

Abstract The ascent of water from the soil to leaves vascular plants, described by study plant hydraulics, regulates ecosystem responses environmental forcing and recovery stress periods. Several approaches model hydraulics have been proposed. In this study, we introduce four different versions representations in terrestrial biosphere T&C understand significance functioning. We tested investigating capacitance, long‐term xylem damages following drought. models were a combination including or neglecting capacitance damage legacies. Using at six case studies spanning semiarid tropical ecosystems, quantify how flow, storage can modulate overall carbon dynamics across multiple time scales. show that as drought develops, with predict slower onset stress, diurnal variability fluxes closer observations. Plant was found be particularly important for fluxes, include yielding better results. Models permanent conducting tissues an additional significant legacy effect, limiting productivity during phase major droughts. However, when considering observed climate variability, hydraulic modules alone cannot significantly improve performance, even though they reproduce more realistic dynamics. This opens new avenues development, explicitly linking processes, such phenology improved allocation algorithms.

Язык: Английский

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High vapour pressure deficit enhances turgor limitation of stem growth in an Asian tropical rainforest tree

Plant Cell & Environment, Год журнала: 2023, Номер 46(9), С. 2747 - 2762

Опубликована: Июль 10, 2023

Abstract Tropical forests are experiencing increases in vapour pressure deficit ( D ), with possible negative impacts on tree growth. Tree‐growth reduction due to rising is commonly attributed carbon limitation, thus overlooking the potentially important mechanism of D‐ induced impairment wood formation an increase turgor limitation. Here we calibrate a mechanistic tree‐growth model simulate limitation radial stem growth mature Toona cilitata trees Asian tropical forest. Hourly sap flow and dendrometer measurements were collected turgor‐driven during growing season. Simulated seasonal patterns matched well observations. Growth mainly occurred at night its pre‐dawn build‐up appeared be limited under higher . Across seasons, night‐time required for was negatively related previous midday , possibly relatively high canopy conductance relative rehydration. These findings provide first evidence that grow limits We suggest including models also forest dynamics, particular, if these effects warming increased frequency droughts.

Язык: Английский

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Unpacking the point of no return under drought in poplar: insight from stem diameter variation

New Phytologist, Год журнала: 2024, Номер 242(2), С. 466 - 478

Опубликована: Фев. 26, 2024

Summary A specific, robust threshold for drought‐induced tree mortality is needed to improve the prediction of forest dieback. Here, we tested relevance continuous measurements stem diameter variations identifying such a threshold, their relationship with hydraulic and cellular damage mechanisms, influence growth conditions on these relationships. Poplar saplings were grown under well‐watered, water‐limited, or light‐limited then submitted drought followed by rewatering. Stem was continuously measured investigate two parameters: percentage loss (PLD) recovery (DR) following Water potentials, stomatal conductance, embolism, electrolyte leakage also measured, light microscopy allowed investigating cell collapse induced drought. The water release observed through occurred throughout drought, regardless conditions. Poplars did not recover from when PLD reached this differed according but remained linked resistance collapse. Our findings shed new mechanisms indicate that could be relevant indicator mortality,

Язык: Английский

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Can mixing Quercus robur and Quercus petraea with Pinus sylvestris compensate for productivity losses due to climate change?

The Science of The Total Environment, Год журнала: 2024, Номер 942, С. 173342 - 173342

Опубликована: Июнь 5, 2024

Язык: Английский

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