Linking plant hydraulics and the fast–slow continuum to understand resilience to drought in tropical ecosystems

New Phytologist, Journal Year: 2021, Volume and Issue: 230(3), P. 904 - 923

Published: Feb. 11, 2021

Summary Tropical ecosystems have the highest levels of biodiversity, cycle more water and absorb carbon than any other terrestrial ecosystem on Earth. Consequently, these are extremely important components Earth’s climatic system biogeochemical cycles. Plant hydraulics is an essential discipline to understand predict dynamics tropical vegetation in scenarios changing availability. Using published plant hydraulic data we show that trade‐off between drought avoidance (expressed as deep‐rooting, deciduousness capacitance) safety (P50 – potential when plants lose 50% their maximum conductivity) a major axis physiological variation across ecosystems. We also propose novel independent trait linking vulnerability failure margin (HSM)) growth, where inherent fast‐growing lower HSM compared slow‐growing plants. surmise soil nutrients fundamental drivers community assembly determining distribution abundance slow‐safe/fast‐risky strategies. conclude showing including either growth‐HSM or resistance‐avoidance models can make simulated rainforest communities substantially vulnerable similar without trade‐off. These results suggest need represent axes accurately project functioning

Language: Английский

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A catastrophic tropical drought kills hydraulically vulnerable tree species

Global Change Biology, Journal Year: 2020, Volume and Issue: 26(5), P. 3122 - 3133

Published: Feb. 13, 2020

Abstract Drought‐related tree mortality is now a widespread phenomenon predicted to increase in magnitude with climate change. However, the patterns of which species and trees are most vulnerable drought, underlying mechanisms have remained elusive, part due lack relevant data difficulty predicting location catastrophic drought years advance. We used long‐term demographic records extensive databases functional traits distribution understand responses 20–53 an extreme seasonally dry tropical forest Costa Rica, occurred during 2015 El Niño Southern Oscillation event. Overall, species‐specific rates ranged from 0% 34%, varied little as function size. By contrast, hydraulic safety margins correlated well probability among species, while morphological or leaf economics spectrum did not. This firmly suggests targets for future research.

Language: Английский

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Non-structural carbohydrates mediate seasonal water stress across Amazon forests

Nature Communications, Journal Year: 2021, Volume and Issue: 12(1)

Published: April 19, 2021

Abstract Non-structural carbohydrates (NSC) are major substrates for plant metabolism and have been implicated in mediating drought-induced tree mortality. Despite their significance, NSC dynamics tropical forests remain little studied. We present leaf branch data 82 Amazon canopy species six sites spanning a broad precipitation gradient. During the wet season, total (NSC T ) concentrations both organs were remarkably similar across communities. However, its soluble sugar (SS) starch components varied much more during dry season. Notably, proportion of form SS (SS:NSC increased greatly season almost all driest sites, implying an important role water stress these sites. This adjustment balance was not observed less-adapted to deficit, even under exceptionally conditions. Thus, carbon may help explain floristic sorting availability gradients Amazonia enable better prediction forest responses future climate change.

Language: Английский

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Basin-wide variation in tree hydraulic safety margins predicts the carbon balance of Amazon forests

Nature, Journal Year: 2023, Volume and Issue: 617(7959), P. 111 - 117

Published: April 26, 2023

Abstract Tropical forests face increasing climate risk 1,2 , yet our ability to predict their response change is limited by poor understanding of resistance water stress. Although xylem embolism thresholds (for example, $$\varPsi $$ Ψ 50 ) and hydraulic safety margins HSM are important predictors drought-induced mortality 3–5 little known about how these vary across Earth’s largest tropical forest. Here, we present a pan-Amazon, fully standardized traits dataset use it assess regional variation in drought sensitivity trait species distributions long-term forest biomass accumulation. Parameters markedly the Amazon related average rainfall characteristics. Both influence biogeographical distribution tree species. However, was only significant predictor observed decadal-scale changes biomass. Old-growth with wide gaining more than low forests. We propose that this may be associated growth–mortality trade-off whereby trees consisting fast-growing take greater risks risk. Moreover, regions pronounced climatic change, find evidence losing biomass, suggesting operating beyond limits. Continued likely further reduce 6,7 strong implications for carbon sink.

Language: Английский

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Global increase in the occurrence and impact of multiyear droughts

Science, Journal Year: 2025, Volume and Issue: 387(6731), P. 278 - 284

Published: Jan. 16, 2025

Persistent multiyear drought (MYD) events pose a growing threat to nature and humans in changing climate. We identified inventoried global MYDs by detecting spatiotemporally contiguous climatic anomalies, showing that have become drier, hotter, led increasingly diminished vegetation greenness. The terrestrial land affected has increased at rate of 49,279 ± 14,771 square kilometers per year from 1980 2018. Temperate grasslands exhibited the greatest declines greenness during MYDs, whereas boreal tropical forests had comparably minor responses. With becoming more common, this quantitative inventory occurrence, severity, trend, impact provides an important benchmark for facilitating effective collaborative preparedness toward mitigation adaptation such extreme events.

Language: Английский

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Amazonia trees have limited capacity to acclimate plant hydraulic properties in response to long‐term drought

Global Change Biology, Journal Year: 2020, Volume and Issue: 26(6), P. 3569 - 3584

Published: Feb. 15, 2020

Abstract The fate of tropical forests under future climate change is dependent on the capacity their trees to adjust drier conditions. withstand drought likely be determined by traits associated with hydraulic systems. However, data whether can when experiencing remain rare. We measured plant (e.g. conductivity and embolism resistance) system status leaf water potential, native safety margin) >150 from 12 genera (36 species) spanning a stem size range 14 68 cm diameter at breast height world's only long‐running forest experiment. Hydraulic showed no adjustment following 15 years experimentally imposed moisture deficit. This failure resulted in these drought‐stressed significantly lower potentials, higher, but variable, levels branches. result suggests that damage caused elevated one key drivers drought‐induced mortality long‐term soil demonstrate some changed tree size, however, direction magnitude was controlled taxonomic identity. Our results suggest Amazonian trees, both small large, have limited acclimate systems droughts, potentially making them more risk mortality.

Language: Английский

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Recurrent droughts increase risk of cascading tipping events by outpacing adaptive capacities in the Amazon rainforest

Proceedings of the National Academy of Sciences, Journal Year: 2022, Volume and Issue: 119(32)

Published: Aug. 2, 2022

Tipping elements are nonlinear subsystems of the Earth system that have potential to abruptly shift another state if environmental change occurs close a critical threshold with large consequences for human societies and ecosystems. Among these tipping may be Amazon rainforest, which has been undergoing intensive anthropogenic activities increasingly frequent droughts. Here, we assess how extreme deviations from climatological rainfall regimes cause local forest collapse cascades through coupled forest–climate system. We develop conceptual dynamic network model isolate uncover role atmospheric moisture recycling in such cascades. account heterogeneity thresholds caused by adaptation climatic conditions. Our results reveal that, despite this adaptation, future climate characterized permanent drought conditions could trigger transition an open canopy particularly southern Amazon. The loss contributes one-third events. Thus, exceeding adaptive capacity, impacts propagate other regions basin, causing risk shifts even where not crossed locally.

Language: Английский

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Small and slow is safe: On the drought tolerance of tropical tree species

Global Change Biology, Journal Year: 2022, Volume and Issue: 28(8), P. 2622 - 2638

Published: Jan. 10, 2022

Understanding how evolutionary history and the coordination between trait trade-off axes shape drought tolerance of trees is crucial to predict forest dynamics under climate change. Here, we compiled traits related fast-slow stature-recruitment in 601 tropical woody species explore their covariations phylogenetic signals. We found that xylem resistance embolism (P50) determines risk hydraulic failure, while functional significance leaf turgor loss point (TLP) relies on its with water use strategies. P50 TLP exhibit weak signals substantial variation within genera. closely associated axis: slow maintain functioning higher stress. both axes: small more resistant xylem. Lower phosphorus concentration xylem, which suggests a (nutrient drought) stress-tolerance syndrome tropics. Overall, our results imply (1) strong selective pressure forests, result from repeated adaptation taxa, (2) coordinated ecological strategies governing demography. These findings provide physiological basis interpret drought-induced shift toward slow-growing, smaller, denser-wooded observed tropics, implications for restoration programmes.

Language: Английский

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Global ecosystem-scale plant hydraulic traits retrieved using model–data fusion

Hydrology and earth system sciences, Journal Year: 2021, Volume and Issue: 25(5), P. 2399 - 2417

Published: May 10, 2021

Abstract. Droughts are expected to become more frequent and severe under climate change, increasing the need for accurate predictions of plant drought response. This response varies substantially, depending on properties that regulate water transport storage within plants, i.e., hydraulic traits. It is, therefore, crucial map traits at a large scale better assess impacts. Improved understanding global variations in is also needed parameterizing latest generation land surface models, many which explicitly simulate processes first time. Here, we use model–data fusion approach evaluate spatial pattern across globe. integrates model with data sets derived from microwave remote sensing inform ecosystem-scale regulation. In particular, both soil moisture vegetation optical depth (VOD) X-band Japan Aerospace Exploration Agency (JAXA) Advanced Microwave Scanning Radiometer Earth Observing System (EOS; collectively AMSR-E). VOD proportional content and, closely related leaf potential. addition, evapotranspiration (ET) Atmosphere–Land Exchange Inverse (ALEXI) used as constraint derive The compared independent sources based ground measurements. Using K-means clustering method, build six functional types (HFTs) distinct trait combinations – mathematically tractable alternatives common assigning values types. averaged by HFTs rather than (PFTs) improves ET estimation accuracies majority areas and/or this study will contribute improved parameterization hydraulics large-scale models prediction ecosystem

Language: Английский

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Forest fragmentation impacts the seasonality of Amazonian evergreen canopies

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: Feb. 17, 2022

Predictions of the magnitude and timing leaf phenology in Amazonian forests remain highly controversial. Here, we use terrestrial LiDAR surveys every two weeks spanning wet dry seasons Central Amazonia to show that plant varies strongly across vertical strata old-growth forests, but is sensitive disturbances arising from forest fragmentation. In combination with continuous microclimate measurements, find when maximum daily temperatures reached 35 °C latter part season, upper canopy large trees undisturbed lost material. contrast, understory greened up increased light availability driven by loss, alongside increases solar radiation, even during periods drier soil atmospheric conditions. However, persistently high edges exacerbated losses throughout whereas these light-rich environments was less dependent on altered structure. Our findings reveal a strong influence edge effects phenological controls Amazonia.

Language: Английский

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