Triggers of tree mortality under drought

Nature, Год журнала: 2018, Номер 558(7711), С. 531 - 539

Опубликована: Июнь 1, 2018

Язык: Английский

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Plant resistance to drought depends on timely stomatal closure

Ecology Letters, Год журнала: 2017, Номер 20(11), С. 1437 - 1447

Опубликована: Сен. 18, 2017

Abstract Stomata play a significant role in the Earth's water and carbon cycles, by regulating gaseous exchanges between plant atmosphere. Under drought conditions, stomatal control of transpiration has long been thought to be closely coordinated with decrease hydraulic capacity (hydraulic failure due xylem embolism). We tested this hypothesis coupling meta‐analysis functional traits related response embolism resistance simulations from soil–plant model. report here previously unreported phenomenon: existence an absolute limit which stomata closure must occur avoid rapid death conditions. The potential causing pressure at onset formation were equal for only small number species, difference these two (i.e. safety margins) increased continuously increasing resistance. Our findings demonstrate need revise current views about coordination provide mechanistic framework modeling mortality under

Язык: Английский

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Hanging by a thread? Forests and drought

Science, Год журнала: 2020, Номер 368(6488), С. 261 - 266

Опубликована: Апрель 16, 2020

Trees are the living foundations on which most terrestrial biodiversity is built. Central to success of trees their woody bodies, connect elevated photosynthetic canopies with essential belowground activities water and nutrient acquisition. The slow construction these carbon-dense, skeletons leads a generation time, leaving forests highly susceptible rapid changes in climate. Other long-lived, sessile organisms such as corals appear be poorly equipped survive changes, raises questions about vulnerability contemporary future climate change. emerging view that, similar corals, tree species have rather inflexible damage thresholds, particularly terms stress, especially concerning. This Review examines recent progress our understanding how looks for growing hotter drier atmosphere.

Язык: Английский

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Iso/Anisohydry: A Plant–Environment Interaction Rather Than a Simple Hydraulic Trait

Trends in Plant Science, Год журнала: 2017, Номер 23(2), С. 112 - 120

Опубликована: Дек. 6, 2017

Язык: Английский

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Embolism resistance drives the distribution of Amazonian rainforest tree species along hydro‐topographic gradients

New Phytologist, Год журнала: 2018, Номер 221(3), С. 1457 - 1465

Опубликована: Окт. 8, 2018

Summary Species distribution is strongly driven by local and global gradients in water availability but the underlying mechanisms are not clear. Vulnerability to xylem embolism (P 50 ) a key trait that indicates how species cope with drought might explain plant patterns across environmental gradients. Here we address its role on sorting along hydro‐topographical gradient central Amazonian rainforest examine variance at community scale. We measured P for 28 tree species, soil properties estimated hydrological niche of each using an indicator distance table ( HAND ). found large hydraulic diversity, covering as much 44% angiosperm variation . show : contributes segregation hydro‐topographic Amazon, thus coexistence; result repeated evolutionary adaptation within closely related taxa; associated tolerance P‐poor soils, suggesting evolution stress‐tolerance syndrome nutrients drought; higher trees valleys than uplands. The observed diversity association topography has important implications modelling predicting forest resilience climate change.

Язык: Английский

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Hydraulic failure and tree size linked with canopy die‐back in eucalypt forest during extreme drought

New Phytologist, Год журнала: 2021, Номер 230(4), С. 1354 - 1365

Опубликована: Фев. 25, 2021

Eastern Australia was subject to its hottest and driest year on record in 2019. This extreme drought resulted massive canopy die-back eucalypt forests. The role of hydraulic failure tree size three species during this examined. We measured pre-dawn midday leaf water potential (Ψleaf ), per cent loss stem conductivity quantified vulnerability drought-induced xylem embolism. Tree health also surveyed. Trees with most, or all, their foliage dead exhibited high rates native embolism (78-100%). is contrast trees partial (30-70% die-back: 72-78% embolism), relatively healthy (little evidence 25-31% embolism). Midday Ψleaf significantly more negative exhibiting (-2.7 -6.3 MPa), compared (-2.1 -4.5 MPa). In two the majority individuals showing complete were small classes. Our results indicate that strongly associated study provides valuable field data help constrain models predicting mortality risk.

Язык: Английский

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Recent advances on phylogenomics of gymnosperms and a new classification

Plant Diversity, Год журнала: 2022, Номер 44(4), С. 340 - 350

Опубликована: Май 26, 2022

Living gymnosperms comprise four major groups: cycads, Ginkgo, conifers, and gnetophytes. Relationships among/within these lineages have not been fully resolved. Next generation sequencing has made available a large number of sequences, including both plastomes single-copy nuclear genes, for reconstruction solid phylogenetic trees. Recent advances in gymnosperm phylogenomic studies updated our knowledge systematics. Here, we review phylogeny over the past 10 years propose an classification extant gymnosperms. This new includes three classes (Cycadopsida, Ginkgoopsida, Pinopsida), five subclasses (Cycadidae, Ginkgoidae, Cupressidae, Pinidae, Gnetidae), eight orders (Cycadales, Ginkgoales, Araucariales, Cupressales, Pinales, Ephedrales, Gnetales, Welwitschiales), 13 families, 86 genera. We also described six tribes Acmopyleae Y. Yang, Austrocedreae Chamaecyparideae Microcachrydeae Papuacedreae Prumnopityeae 27 combinations genus Sabina.

Язык: Английский

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Tree hydraulic traits are coordinated and strongly linked to climate‐of‐origin across a rainfall gradient

Plant Cell & Environment, Год журнала: 2018, Номер 41(3), С. 646 - 660

Опубликована: Янв. 9, 2018

Abstract Plant hydraulic traits capture the impacts of drought stress on plant function, yet vegetation models lack sufficient information regarding trait coordination and variation with climate‐of‐origin across species. Here, we investigated key carbon economy 12 woody species in Australia from a broad climatic gradient, aim identifying among these role climate shaping cross‐species variation. The influence environmental was minimized by common garden approach, allowing us to factor out environment phenotypic We found that (leaf turgor loss point, stomatal sensitivity [P gs ], xylem vulnerability cavitation x branch capacitance [C ]) were highly coordinated strongly related rainfall aridity native distributional range. In addition, trade‐offs between tolerance growth rate observed Collectively, results provide critical insight into modulating adaptation will significantly advance our ability predict dominant trees

Язык: Английский

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Low Vulnerability to Xylem Embolism in Leaves and Stems of North American Oaks

PLANT PHYSIOLOGY, Год журнала: 2018, Номер 177(3), С. 1066 - 1077

Опубликована: Май 22, 2018

Although recent findings suggest that xylem embolism represents a significant, drought-induced damaging process in land plants, substantial debate surrounds the capacity of long-vesseled, ring-porous species to resist embolism. We investigated whether methodological developments could help resolve this controversy within Quercus, temperate angiosperm genus, and shed further light on importance vulnerability as an indicator drought tolerance. used optical technique quantify leaf stem eight Quercus from Mediterranean-type climate region California examine absolute measures resistance well any potential hydraulic segmentation between tissue types. demonstrated our assessment reflected flow impairment for subset sample by quantifying changes conductance dehydrating branches. Air-entry water varied 2-fold leaves, ranging -1.7 ± 0.25 MPa -3.74 0.23 MPa, 4-fold stems, -1.17 0.04 -4.91 0.3 MPa. Embolism occurred earlier leaves than stems only one out species, plants always lost turgor before experiencing Our results show long-vesseled North American are more resistant previously thought support hypothesis avoiding is critical component tolerance woody trees. Accurately essential understanding distributions along aridity gradients predicting plant mortality during drought.

Язык: Английский

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Mapping xylem failure in disparate organs of whole plants reveals extreme resistance in olive roots

New Phytologist, Год журнала: 2018, Номер 218(3), С. 1025 - 1035

Опубликована: Март 12, 2018

Summary The capacity of plant species to resist xylem cavitation is an important determinant resistance drought, mortality thresholds, geographic distribution and productivity. Unravelling the role vulnerability in evolution adaptation requires a clear understanding how this key trait varies between tissues individuals species. Here, we examine questions variation within by measuring moves organs individual plants. Using multiple cameras placed simultaneously on roots, stems leaves, were able record systemic during drying olive Unlike previous studies, found consistent pattern root > stem leaf terms cavitation. substantial cavitation, evident among individuals, seedlings, was coordinated such that plants with more resistant roots also had leaves. Preservation integrity means can continue supply water for regeneration drought‐damaged aerial after post‐drought rain. Furthermore, leaf, suggests strong selective pressure maintain fixed order drought.

Язык: Английский

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