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A Simple Stomatal Model That Unifies the Metabolic and Hydraulic Control of Carbon and Water FluxNARA Subscribed
A striking incongruity has long persisted in the modeling framework typically used to predict CO 2 and water vapor exchange between land plants and the atmosphere across scales. Generally, photosynthetic CO 2 demand is estimated using process‐based models of biochemistry, but the biophysical stomatal constraint on photosynthesis and transpiration ( g sw ) is estimated using “black box” empirical or optimization‐based models. E...
‘Water potential’ is the biophysically relevant measure of water status in vegetation relating to stomatal, canopy and hydraulic conductance, as well as mortality thresholds; yet, this cannot be directly related to measured and modelled fluxes of water at plot‐ to landscape‐scale without understanding its relationship with ‘water content’. The capacity for detecting vegetation water content via microwave remote sensing further...
The ecosystem wilting point defines drought response and recovery of a Quercus‐Carya forestNARA Subscribed
Soil and atmospheric droughts increasingly threaten plant survival and productivity around the world. Yet, conceptual gaps constrain our ability to predict ecosystem‐scale drought impacts under climate change. Here, we introduce the ecosystem wilting point (Ψ EWP ), a property that integrates the drought response of an ecosystem's plant community across the soil–plant–atmosphere continuum. Specifically, Ψ EWP defines a thresho...
Leaf habit affects the distribution of drought sensitivity but not water transport efficiency in the tropicsNARA Subscribed
Considering the global intensification of aridity in tropical biomes due to climate change, we need to understand what shapes the distribution of drought sensitivity in tropical plants. We conducted a pantropical data synthesis representing 1117 species to test whether xylem‐specific hydraulic conductivity (K S ), water potential at leaf turgor loss (Ψ TLP ) and water potential at 50% loss of K S (Ψ P50 ) varied along climate...
Leaf trait network architecture shifts with species‐richness and climate across forests at continental scaleNARA Subscribed
Variation in the architecture of trait networks among ecosystems has been rarely quantified, but can provide high resolution of the contrasting adaptation of the whole phenotype. We constructed leaf trait networks (LTNs) from 35 structural, anatomical and compositional leaf traits for 394 tree species in nine forests from tropical to cold‐temperate zones in China. Our analyses supported the hypothesis that LTNs would increase...
Detecting forest response to droughts with global observations of vegetation water contentNARA Subscribed
Droughts in a warming climate have become more common and more extreme, making understanding forest responses to water stress increasingly pressing. Analysis of water stress in trees has long focused on water potential in xylem and leaves, which influences stomatal closure and water flow through the soil‐plant‐atmosphere continuum. At the same time, changes of vegetation water content (VWC) are linked to a range of tree respon...
Global root traits (GRooT) databaseNARA Subscribed
Motivation Trait data are fundamental to the quantitative description of plant form and function. Although root traits capture key dimensions related to plant responses to changing environmental conditions and effects on ecosystem processes, they have rarely been included in large‐scale comparative studies and global models. For instance, root traits remain absent from nearly all studies that define the global spectrum of plan...
TRY plant trait database – enhanced coverage and open accessNARA Subscribed
Plant traits—the morphological, anatomical, physiological, biochemical and phenological characteristics of plants—determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodivers...
Seedling response to water stress in valley oak ( Quercus lobata ) is shaped by different gene networks across populationsNARA Subscribed
Drought is a major stress for plants, creating a strong selection pressure for traits that enable plant growth and survival in dry environments. Many drought responses are conserved species‐wide responses, while others vary among populations distributed across heterogeneous environments. We tested how six populations of the widely distributed California valley oak ( Quercus lobata ) sampled from contrasting climates would diff...
Disentangling the functional trait correlates of spatial aggregation in tropical forest treesNARA Subscribed
Environmental filtering and dispersal limitation can both maintain diversity in plant communities by aggregating conspecifics, but parsing the contribution of each process has proven difficult empirically. Here, we assess the contribution of filtering and dispersal limitation to the spatial aggregation patterns of 456 tree species in a hyperdiverse Amazonian forest and find distinct functional trait correlates of interspecific...
Front CoverNARA Subscribed
Global importance of large‐diameter treesNARA Subscribed
Aim To examine the contribution of large‐diameter trees to biomass, stand structure, and species richness across forest biomes. Location Global. Time period Early 21st century. Major taxa studied Woody plants. Methods We examined the contribution of large trees to forest density, richness and biomass using a global network of 48 large (from 2 to 60 ha) forest plots representing 5,601,473 stems across 9,298 species and 210 plan...
Aim To determine the role of regional forcing on plot‐level species diversity and composition, and to quantify the relative importance of biogeographical and climatic factors in explaining woody plant diversity and composition at the local‐, island‐ and archipelago‐scale. Location Forty‐one tropical islands of the Indo‐Pacific region from Madagascar to Hawai‘i Island. Methods We analysed the diversity and composition of tropic...
The anatomical and compositional basis of leaf mass per areaNARA Subscribed
Leaf dry mass per unit leaf area (LMA) is a central trait in ecology, but its anatomical and compositional basis has been unclear. An explicit mathematical and physical framework for quantifying the cell and tissue determinants of LMA will enable tests of their influence on species, communities and ecosystems. We present an approach to explaining LMA from the numbers, dimensions and mass densities of leaf cells and tissues, wh...
Does climate directly influence NPP globally?NARA Subscribed
The need for rigorous analyses of climate impacts has never been more crucial. Current textbooks state that climate directly influences ecosystem annual net primary productivity ( NPP ), emphasizing the urgent need to monitor the impacts of climate change. A recent paper challenged this consensus, arguing, based on an analysis of NPP for 1247 woody plant communities across global climate gradients, that temperature and precipi...
Global change is impacting forests worldwide, threatening biodiversity and ecosystem services including climate regulation. Understanding how forests respond is critical to forest conservation and climate protection. This review describes an international network of 59 long‐term forest dynamics research sites ( CTFS ‐Forest GEO ) useful for characterizing forest responses to global change. Within very large plots (median size...
Many species face increasing drought under climate change. Plasticity has been predicted to strongly influence species' drought responses, but broad patterns in plasticity have not been examined for key drought tolerance traits, including turgor loss or ‘wilting’ point (π tlp ). As soil dries, plants shift π tlp by accumulating solutes (i.e. ‘osmotic adjustment’). We conducted the first global analysis of plasticity in Δπ tlp...
The determinants of leaf turgor loss point and prediction of drought tolerance of species and biomes: a global meta‐analysisNARA Subscribed
Ecology Letters (2012) 15 : 393–405 Abstract Increasing drought is one of the most critical challenges facing species and ecosystems worldwide, and improved theory and practices are needed for quantification of species tolerances. Leaf water potential at turgor loss, or wilting (π tlp ), is classically recognised as a major physiological determinant of plant water stress response. However, the cellular basis of π tlp and its i...
Comparative water use of native and invasive plants at multiple scales: a global meta‐analysisNARA Subscribed
Ecohydrology and invasive ecology have become increasingly important in the context of global climate change. This study presents the first in‐depth analysis of the water use of invasive and native plants of the same growth form at multiple scales: leaf, plant, and ecosystem. We reanalyzed data for several hundred native and invasive species from over 40 published studies worldwide to glean global trends and to highlight how p...