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Berry E, Anfodillo T, Castorena M, Echeverría A, Olson ME. Scaling of leaf area with biomass in trees reconsidered: constant metabolically active sapwood volume per unit leaf area with height growth. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:3993-4004. [PMID: 38634646 DOI: 10.1093/jxb/erae160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 04/15/2024] [Indexed: 04/19/2024]
Abstract
Hypoallometric (slope<1) scaling between metabolic rate and body mass is often regarded as near-universal across organisms. However, there are compelling reasons to question hypoallometric scaling in woody plants, where metabolic rate is directly proportional to leaf area. This leaf area must provide carbon to the volume of the metabolically active sapwood (VMASW). Within populations of a species, variants in which VMASW increases per unit leaf area with height growth (e.g. ⅔ or ¾ scaling) would have proportionally less carbon for growth and reproduction as they grow taller. Therefore, selection should favor individuals in which, as they grow taller, leaf area scales isometrically with shoot VMASW (slope=1). Using tetrazolium staining, we measured total VMASW and total leaf area (LAtot) across 22 individuals of Ricinus communis and confirmed that leaf area scales isometrically with VMASW, and that VMASW is much smaller than total sapwood volume. With the potential of the LAtot-VMASW relationship to shape factors as diverse as the crown area-stem diameter relationship, conduit diameter scaling, reproductive output, and drought-induced mortality, our work indicates that the notion that sapwood increases per unit leaf area with height growth requires revision.
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Affiliation(s)
- Eapsa Berry
- Instituto de Biología, Universidad Nacional Autónoma de México, Tercer Circuito sn de Ciudad Universitaria, Ciudad de México 04510, Mexico
| | - Tommaso Anfodillo
- Department Territorio e Sistemi Agro-Forestali, University of Padova, Legnaro (PD) 35020, Italy
| | - Matiss Castorena
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85719, USA
| | - Alberto Echeverría
- Instituto de Biología, Universidad Nacional Autónoma de México, Tercer Circuito sn de Ciudad Universitaria, Ciudad de México 04510, Mexico
| | - Mark E Olson
- Instituto de Biología, Universidad Nacional Autónoma de México, Tercer Circuito sn de Ciudad Universitaria, Ciudad de México 04510, Mexico
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Anfodillo T, Olson ME. Stretched sapwood, ultra-widening permeability and ditching da Vinci: revising models of plant form and function. ANNALS OF BOTANY 2024; 134:19-42. [PMID: 38634673 PMCID: PMC11161570 DOI: 10.1093/aob/mcae054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Accepted: 04/14/2024] [Indexed: 04/19/2024]
Abstract
BACKGROUND The mechanisms leading to dieback and death of trees under drought remain unclear. To gain an understanding of these mechanisms, addressing major empirical gaps regarding tree structure-function relations remains essential. SCOPE We give reasons to think that a central factor shaping plant form and function is selection simultaneously favouring constant leaf-specific conductance with height growth and isometric (1:1) scaling between leaf area and the volume of metabolically active sink tissues ('sapwood'). Sapwood volume-leaf area isometry implies that per-leaf area sapwood volumes become transversely narrower with height growth; we call this 'stretching'. Stretching means that selection must favour increases in permeability above and beyond that afforded by tip-to-base conduit widening ("ultra-widening permeability"), via fewer and wider vessels or tracheids with larger pits or larger margo openings. Leaf area-metabolically active sink tissue isometry would mean that it is unlikely that larger trees die during drought because of carbon starvation due to greater sink-source relationships as compared to shorter plants. Instead, an increase in permeability is most plausibly associated with greater risk of embolism, and this seems a more probable explanation of the preferential vulnerability of larger trees to climate change-induced drought. Other implications of selection favouring constant per-leaf area sapwood construction and maintenance costs are departure from the da Vinci rule expectation of similar sapwood areas across branching orders, and that extensive conduit furcation in the stem seems unlikely. CONCLUSIONS Because all these considerations impact the likelihood of vulnerability to hydraulic failure versus carbon starvation, both implicated as key suspects in forest mortality, we suggest that these predictions represent essential priorities for empirical testing.
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Affiliation(s)
- Tommaso Anfodillo
- Department Territorio e Sistemi Agro-Forestali, University of Padova, Legnaro (PD) 35020, Italy
| | - Mark E Olson
- Instituto de Biología, Universidad Nacional Autónoma de México, Tercer Circuito sn de Ciudad Universitaria, Ciudad de México 04510, Mexico
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Kafuti C, Lehnebach R, Bourland N, Beeckman H, Van Acker J, Luambua NK, Van den Bulcke J. Earlier onset and slower heartwood investment in faster-growing trees of African tropical species. ANNALS OF BOTANY 2024; 133:905-916. [PMID: 37409979 PMCID: PMC11082515 DOI: 10.1093/aob/mcad079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 07/04/2023] [Indexed: 07/07/2023]
Abstract
BACKGROUND AND AIMS Heartwood plays an important role in maintaining the structural integrity of trees. Although its formation has long been thought to be driven solely by internal ageing processes, more recent hypotheses suggest that heartwood formation acts as a regulator of the tree water balance by modulating the quantity of sapwood. Testing both hypotheses would shed light on the potential ecophysiological nature of heartwood formation, a very common process in trees. METHODS We measured quantities of heartwood and sapwood, xylem conduits and the width and number of growth rings on 406 stems of Pericopsis elata with ages ranging from 2 to 237 years. A subset of 17 trees with similar ages but varying growth rate were sampled in a shaded (slower-growth) site and a sun-exposed (faster-growth) site. We used regression analysis and structural equation modelling to investigate the dynamics and drivers of heartwood formation. KEY RESULTS We found a positive effect of growth rate on the probability of heartwood occurrence, suggesting an earlier heartwood onset in faster-growing stems. After this onset age, heartwood area increased with stem diameter and age. Despite the similar heartwood production per unit stem diameter increment, shaded trees produced heartwood faster than sun-exposed trees. Tree age and hydraulics showed similar direct effects on heartwood and sapwood area of sun-exposed trees, suggesting their mutual role in driving the heartwood dynamics of sun-exposed trees. However, for shaded trees, only tree hydraulics showed a direct effect, suggesting its prominent role over age in driving the heartwood dynamics in limited growing conditions. The positive relationship between growth rate and maximum stomatal conductance supported this conclusion. CONCLUSIONS Heartwood area increases as the tree ages, but at a slower rate in trees where water demand is balanced by a sufficient water supply. Our findings suggest that heartwood formation is not only a structural process but also functional.
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Affiliation(s)
- Chadrack Kafuti
- UGent-Woodlab, Laboratory of Wood Technology, Department of Environment, Ghent University, Coupure Links 653, 9000 Gent, Belgium
- Service of Wood Biology, Royal Museum for Central Africa, Leuvensesteenweg 13, 3080 Tervuren, Belgium
- Faculty of Agricultural Sciences, Department of Natural Resources Management, University of Kinshasa, 117 Kinshasa XI, Democratic Republic of the Congo
| | - Romain Lehnebach
- UGent-Woodlab, Laboratory of Wood Technology, Department of Environment, Ghent University, Coupure Links 653, 9000 Gent, Belgium
- CIRAD, UMR Ecologie des Forêts de Guyane (EcoFoG), AgroParisTech, CNRS, INRA, Université Des Antilles, Université de Guyane, 97310 Kourou, France
| | - Nils Bourland
- Service of Wood Biology, Royal Museum for Central Africa, Leuvensesteenweg 13, 3080 Tervuren, Belgium
- Center for International Forestry Research, Situ Gede, Sindang Barang, Bogor (Barat) 16115, Indonesia
| | - Hans Beeckman
- Service of Wood Biology, Royal Museum for Central Africa, Leuvensesteenweg 13, 3080 Tervuren, Belgium
| | - Joris Van Acker
- UGent-Woodlab, Laboratory of Wood Technology, Department of Environment, Ghent University, Coupure Links 653, 9000 Gent, Belgium
| | - Nestor K Luambua
- Service of Wood Biology, Royal Museum for Central Africa, Leuvensesteenweg 13, 3080 Tervuren, Belgium
- Faculté des sciences Agronomiques, Université Officielle de Mbujimayi, Mbujimayi, Democratic Republic of Congo
| | - Jan Van den Bulcke
- UGent-Woodlab, Laboratory of Wood Technology, Department of Environment, Ghent University, Coupure Links 653, 9000 Gent, Belgium
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Segovia-Rivas A, Olson ME. Temperature and Turgor "Limitation" and Environmental "Control" in Xylem Biology and Dendrochronology. Integr Comp Biol 2023; 63:1364-1375. [PMID: 37550219 DOI: 10.1093/icb/icad110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 07/23/2023] [Accepted: 07/28/2023] [Indexed: 08/09/2023] Open
Abstract
Trees and other woody plants are immensely ecologically important, making it essential to understand the causes of relationships between tree structure and function. To help these efforts, we highlight persistent traditions in plant biology of appealing to environmental factors "limiting" or "controlling" woody plant features. Examples include the idea that inevitable drops in cell turgor with plant height limit cell expansion and thus leaf size and tree height; that low temperatures prohibit lignification of cells and thus the growth of woody plants at high elevation; and notions from dendrochronology and related fields that climate factors such as rainfall and temperature "control" growth ring features. We show that notions of "control," "limitation," and the like imply that selection would favor a given trait value, but that these would-be favored values are developmentally impossible to produce. Such "limitation" scenarios predict trait frequency distributions that are very narrow and are abruptly curtailed at the upper limit of developmental possibility (the right-hand side of the distribution). Such distributions have, to our knowledge, never been observed, so we see little empirical support for "limitation" hypotheses. We suggest that, as a more productive starting point, plant biologists should examine adaptation hypotheses, in which developmental possibility is wide (congruent with the wide ranges of trait variation that really are observed), but only some of the possible variants are favored. We suggest that (1) the traditional the proximate/ultimate causation distinction, (2) purging scenarios of teleology/anthropomorphism, and (3) stating hypotheses in terms of developmental potential and natural selection are three simple ways of making "limitation" hypotheses clearer with regard to biological process and thus empirically testable.
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Affiliation(s)
- Alí Segovia-Rivas
- Instituto de Biología, , Universidad Nacional Autónoma de México, Tercer Circuito sn de Ciudad Universitaria, Ciudad de México 04510, Mexico
| | - Mark E Olson
- Instituto de Biología, , Universidad Nacional Autónoma de México, Tercer Circuito sn de Ciudad Universitaria, Ciudad de México 04510, Mexico
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Avalos G, Cambronero M, Alvarez-Vergnani C. Divergence in functional traits in seven species of neotropical palms of different forest strata. Oecologia 2023; 203:323-333. [PMID: 37875736 DOI: 10.1007/s00442-023-05466-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 10/12/2023] [Indexed: 10/26/2023]
Abstract
Functional traits are morphological and physiological characteristics that determine growth, reproduction, and survival strategies. The leaf economics spectrum proposes two opposing life history strategies: species with an "acquisitive" strategy grow fast and exploit high-resource environments, while species with a "conservative" strategy emphasize survival and slow growth under low resource conditions. We analyzed intra and interspecific variation in nine functional traits related to biomass allocation and tissue quality in seven Neotropical palm species from understory and canopy strata. We expected that the level of resources of a stratum that a species typically exploits would determine the dominance of either the exploitative or conservative strategy, as well as degree of divergence in functional traits between species. If this is correct, then canopy species will show an acquisitive strategy emphasizing traits targeting a larger size, whereas understory species will show a conservative strategy with traits promoting efficient biomass allocation and survival in the shade. Two principal components (57.22% of the variation) separated palm species into: (a) canopy species whose traits were congruent with the acquisitive strategy and emphasized large size (i.e., diameter, height, carbon content, and leaf area), and (b) understory species whose traits were associated with efficient biomass allocation (i.e., dry mass fraction -DMF- and tissue density). As we unravel the variation in functional traits in palms, which make up a substantial proportion of the tropical flora, we gain a deeper understanding of how plants adapt to environmental gradients.
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Affiliation(s)
- Gerardo Avalos
- Escuela de Biología, Universidad de Costa Rica, San Pedro, San José, 11501-2060, Costa Rica.
- The School for Field Studies, Center for Ecological Resilience Studies, 100 Cummings Center, Suite 534G, Beverly, MA, 01915, USA.
| | - Milena Cambronero
- The School for Field Studies, Center for Ecological Resilience Studies, 100 Cummings Center, Suite 534G, Beverly, MA, 01915, USA
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Sobral M. Plant subindividual functional diversity and carbon cycling. TRENDS IN PLANT SCIENCE 2023; 28:1357-1359. [PMID: 37775453 DOI: 10.1016/j.tplants.2023.09.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 09/01/2023] [Accepted: 09/08/2023] [Indexed: 10/01/2023]
Abstract
Plant subindividual trait variation is a neglected level of functional diversity that contributes to the variation of phenotypes and ecological communities. Disregarding the role of subindividual functional diversity (SFD) in nature may lead to incorrect understanding of spatial and temporal scales of relationships between trait diversity, ecosystem function, and carbon cycling.
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Affiliation(s)
- Mar Sobral
- Departamento de Edafoloxía e Química Agrícola, Universidade de Santiago de Compostela, Santiago de Compostela, Spain.
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Mungi NA, Jhala YV, Qureshi Q, le Roux E, Svenning JC. Megaherbivores provide biotic resistance against alien plant dominance. Nat Ecol Evol 2023; 7:1645-1653. [PMID: 37652995 DOI: 10.1038/s41559-023-02181-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 07/26/2023] [Indexed: 09/02/2023]
Abstract
While human-driven biological invasions are rapidly spreading, finding scalable and effective control methods poses an unresolved challenge. Here, we assess whether megaherbivores-herbivores reaching ≥1,000 kg of body mass-offer a nature-based solution to plant invasions. Invasive plants are generally adapted to maximize vegetative growth. Megaherbivores, with broad dietary tolerances, could remove large biomass of established plants, facilitating new plant growth. We used a massive dataset obtained from 26,838 camera stations and 158,979 vegetation plots to assess the relationships between megaherbivores, native plants and alien plants across India (~121,330 km2). We found a positive relationship between megaherbivore abundance and native plant richness and abundance, and a concomitant reduction in alien plant abundance. This relationship was strongest in protected areas with midproductive ecosystem and high megaherbivore density but it was lost in areas where thicket-forming alien plants predominated (>40% cover). By incorporating the role of ecosystem productivity, plants traits and densities of megaherbivores on megaherbivore-vegetation relationships, our study highlights a function of megaherbivores in controlling alien plant proliferation and facilitating diverse native plants in invaded ecosystems. The study shows great potential for megafauna-based trophic rewilding as a nature-based solution to counteract dominance of plant invasions.
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Affiliation(s)
- Ninad Avinash Mungi
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) & Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, Aarhus, Denmark.
- Wildlife Institute of India, Dehradun, India.
| | | | | | - Elizabeth le Roux
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) & Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, Aarhus, Denmark
| | - Jens-Christian Svenning
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) & Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, Aarhus, Denmark
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Deng JY, Wang YJ, Chen LF, Luo T, Wang R, Chen XY. Functional trait divergence associated with heteromorphic leaves in a climbing fig. FRONTIERS IN PLANT SCIENCE 2023; 14:1261240. [PMID: 37794929 PMCID: PMC10546399 DOI: 10.3389/fpls.2023.1261240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 09/01/2023] [Indexed: 10/06/2023]
Abstract
Introduction Plants that display heteroblasty possess conspicuous variations in leaf morphology between their juvenile and adult phases, with certain species retaining juvenile-like leaves even in adulthood. Nevertheless, the ecological advantages of maintaining two or more distinct leaf types in heteroblastic plants at the adult stage remain unclear. Method The aim of this study is to examine the adaptive significance of heteroblastic leaves sampled from branches with divergent functions (sterile and fertile branches) of mature Ficus pumila individuals by comparing their morphological, anatomical, and physiological characteristics. Result Leaves on sterile branches (LSs) exhibited a significantly larger specific leaf area, thinner palisade and spongy tissues, lower chlorophyll contents, and lower light saturation points than leaves on fertile branches (LFs). These results demonstrate that LSs are better adapted to low light environments, while LFs are well equipped to take advantages of high light conditions. However, both LFs and LSs have a low light compensation point with no significant difference between them, indicating that they start to accumulate photosynthetic products under similar light conditions. Interestingly, significant higher net photosynthetic rate was detected in LFs, showing they have higher photosynthetic capacity. Furthermore, LFs produced significant more nutrients compared to LSs, which may associate to their ability of accumulating more photosynthetic products under full light conditions and higher photosynthetic capacity. Discussion Overall, we observed a pattern of divergence in morphological features of leaves on two functional branches. Anatomical and physiological features indicate that LFs have an advantage in varied light conditions, providing amounts of photosynthetic products to support the sexual reproduction, while LSs adapt to low light environments. Our findings provide evidence that heteroblasty facilitates F. pumila to utilize varying light environments, likely associated with its growth form as a climbing plant. This strategy allows the plant to allocate resources more effectively and optimize its overall fitness.
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Affiliation(s)
- Jun-Yin Deng
- Zhejiang Tiantong Forest Ecosystem National Observation and Research Station, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, China
| | - Yong-Jin Wang
- Zhejiang Tiantong Forest Ecosystem National Observation and Research Station, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, China
| | - Lu-Fan Chen
- Zhejiang Tiantong Forest Ecosystem National Observation and Research Station, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, China
| | - Tong Luo
- Zhejiang Tiantong Forest Ecosystem National Observation and Research Station, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, China
| | - Rong Wang
- Zhejiang Tiantong Forest Ecosystem National Observation and Research Station, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, China
- Shanghai Institute of Pollution Control & Ecological Security, Shanghai, China
| | - Xiao-Yong Chen
- Zhejiang Tiantong Forest Ecosystem National Observation and Research Station, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, China
- Shanghai Institute of Pollution Control & Ecological Security, Shanghai, China
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Losada M, Sobral M, Silvius KM, Varela S, Martínez Cortizas AM, Fragoso JMV. Mammal traits and soil biogeochemistry: Functional diversity relates to composition of soil organic matter. Ecol Evol 2023; 13:e10392. [PMID: 37600493 PMCID: PMC10433116 DOI: 10.1002/ece3.10392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 07/02/2023] [Accepted: 07/19/2023] [Indexed: 08/22/2023] Open
Abstract
Mammal diversity affects carbon concentration in Amazonian soils. It is known that some species traits determine carbon accumulation in organisms (e.g., size and longevity), and are also related to feeding strategies, thus linking species traits to the type of organic remains that are incorporated into the soil. Trait diversity in mammal assemblages - that is, its functional diversity - may therefore constitute another mechanism linking biodiversity to soil organic matter (SOM) accumulation. To address this hypothesis, we analyzed across 83 mammal assemblages in the Amazon biome (Guyana), the elemental (by ED-XRF and CNH analysis) and molecular (FTIR-ATR) composition of SOM of topsoils (401 samples) and trait diversity (functional richness, evenness, and divergence) for each mammal assemblage. Lower mammal functional richness but higher functional divergence were related to higher content of carbonyl and aliphatic SOM, potentially affecting SOM recalcitrance. Our results might allow the design of biodiversity management plans that consider the effect of mammal traits on carbon sequestration and accumulation in soils.
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Affiliation(s)
- María Losada
- EcoPast (GI‐1553), Departmento de Edafoloxía e Química Agrícola, Facultade de BioloxíaUniversidade de Santiago de CompostelaSantiago de CompostelaSpain
| | - Mar Sobral
- EcoPast (GI‐1553), Departmento de Edafoloxía e Química Agrícola, Facultade de BioloxíaUniversidade de Santiago de CompostelaSantiago de CompostelaSpain
| | - Kirsten M. Silvius
- Department of Forest Resources and Environmental ConservationVirginia TechBlacksburgVirginiaUSA
| | - Sara Varela
- MAPAS Lab, Departamento de Ecoloxía e Bioloxía AnimalUniversidade de VigoVigoSpain
| | - Antonio M. Martínez Cortizas
- CRETUS – EcoPast (GI‐1553), Departmento de Edafoloxía e Química Agrícola, Facultade de BioloxíaUniversidade de Santiago de CompostelaSantiago de CompostelaSpain
| | - José M. V. Fragoso
- Departamento de ZoologiaUniversidade de BrasíliaBrasíliaBrazil
- Institute of Biodiversity Science and SustainabilityCalifornia Academy of SciencesSan FranciscoCaliforniaUSA
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Blonder BW, Aparecido LMT, Hultine KR, Lombardozzi D, Michaletz ST, Posch BC, Slot M, Winter K. Plant water use theory should incorporate hypotheses about extreme environments, population ecology, and community ecology. THE NEW PHYTOLOGIST 2023; 238:2271-2283. [PMID: 36751903 DOI: 10.1111/nph.18800] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 01/30/2023] [Indexed: 05/19/2023]
Abstract
Plant water use theory has largely been developed within a plant-performance paradigm that conceptualizes water use in terms of value for carbon gain and that sits within a neoclassical economic framework. This theory works very well in many contexts but does not consider other values of water to plants that could impact their fitness. Here, we survey a range of alternative hypotheses for drivers of water use and stomatal regulation. These hypotheses are organized around relevance to extreme environments, population ecology, and community ecology. Most of these hypotheses are not yet empirically tested and some are controversial (e.g. requiring more agency and behavior than is commonly believed possible for plants). Some hypotheses, especially those focused around using water to avoid thermal stress, using water to promote reproduction instead of growth, and using water to hoard it, may be useful to incorporate into theory or to implement in Earth System Models.
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Affiliation(s)
- Benjamin Wong Blonder
- Department of Environmental Science, Policy, and Management, University of California Berkeley, Berkeley, CA, 94720, USA
| | - Luiza Maria Teophilo Aparecido
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ, 85287, USA
- Department of Research, Conservation and Collections, Desert Botanical Garden, Phoenix, AZ, 85008, USA
| | - Kevin R Hultine
- Department of Research, Conservation and Collections, Desert Botanical Garden, Phoenix, AZ, 85008, USA
| | - Danica Lombardozzi
- Climate and Global Dynamics Laboratory, National Center for Atmospheric Research, Boulder, CO, 80305, USA
| | - Sean T Michaletz
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Bradley C Posch
- Department of Environmental Science, Policy, and Management, University of California Berkeley, Berkeley, CA, 94720, USA
- Department of Research, Conservation and Collections, Desert Botanical Garden, Phoenix, AZ, 85008, USA
- Department of Biological Sciences, Texas Tech University, Lubbock, TX, 79409, USA
| | - Martijn Slot
- Smithsonian Tropical Research Institute, Balboa, Ancón, 0843-03092, Panama
| | - Klaus Winter
- Smithsonian Tropical Research Institute, Balboa, Ancón, 0843-03092, Panama
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Sobral M, Schleuning M, Martínez Cortizas A. Trait diversity shapes the carbon cycle. Trends Ecol Evol 2023:S0169-5347(23)00061-7. [PMID: 37045717 DOI: 10.1016/j.tree.2023.03.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 03/17/2023] [Accepted: 03/20/2023] [Indexed: 04/14/2023]
Abstract
Trait evolution is shaped by carbon economics at the organismal level. Here, we expand this idea to the ecosystem level and show how the trait diversity of ecological communities influences the carbon cycle. Systematic shifts in trait diversity will likely trigger changes in the carbon cycle.
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Affiliation(s)
- Mar Sobral
- CRETUS, EcoPast (GI-1553), Facultade de Bioloxía, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
| | - Matthias Schleuning
- Senckenberg Biodiversity and Climate Research Centre (SBiK-F), Senckenberganlage 25, 60325 Frankfurt am Main, Germany
| | - Antonio Martínez Cortizas
- CRETUS, EcoPast (GI-1553), Facultade de Bioloxía, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
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12
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Losada M, Martínez Cortizas AM, Silvius KM, Varela S, Raab TK, Fragoso JM, Sobral M. Mammal and tree diversity accumulate different types of soil organic matter in the northern Amazon. iScience 2023; 26:106088. [PMID: 36915677 PMCID: PMC10006633 DOI: 10.1016/j.isci.2023.106088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 12/06/2022] [Accepted: 01/25/2023] [Indexed: 01/31/2023] Open
Abstract
Diversity of plants and animals influence soil carbon through their contributions to soil organic matter (SOM). However, we do not know whether mammal and tree communities affect SOM composition in the same manner. This question is relevant because not all forms of carbon are equally resistant to mineralization by microbes and thus, relevant to carbon storage. We analyzed the elemental and molecular composition of 401 soil samples, with relation to the species richness of 83 mammal and tree communities at a landscape scale across 4.8 million hectares in the northern Amazon. We found opposite effects of mammal and tree richness over SOM composition. Mammal diversity is related to SOM rich in nitrogen, sulfur and iron whereas tree diversity is related to SOM rich in aliphatic and carbonyl compounds. These results help us to better understand the role of biodiversity in the carbon cycle and its implications for climate change mitigation.
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Affiliation(s)
- María Losada
- CRETUS - EcoPast (GI-1553), Departmento de Edafoloxía e Química Agrícola, Facultade de Bioloxía, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Antonio M. Martínez Cortizas
- CRETUS - EcoPast (GI-1553), Departmento de Edafoloxía e Química Agrícola, Facultade de Bioloxía, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
- Bolin Centre for Climate Research, Stockholm University, 106 91 Stockholm, Sweden
| | - Kirsten M. Silvius
- Department of Forest Resources and Environmental Conservation, Virginia Tech University, Blacksburg, VA 24061, USA
| | - Sara Varela
- MAPAS Lab, Departamento de Ecoloxía e Bioloxía Animal, Universidade de Vigo, 36310 Vigo, Spain
| | - Ted K. Raab
- Carnegie Institution for Science, Deparment of Global Ecology, Stanford, CA 94305, USA
| | - Jose M.V. Fragoso
- Departamento de Zoologia, Universidade de Brasılia, Brasılia, DF 70910-900, Brazil
- Institute of Biodiversity Science and Sustainability, California Academy of Sciences, San Francisco, CA 94118, USA
| | - Mar Sobral
- CRETUS - EcoPast (GI-1553), Departmento de Edafoloxía e Química Agrícola, Facultade de Bioloxía, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
- Corresponding author
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Piper FI, Fajardo A. Carbon stress causes earlier budbreak in shade-tolerant species and delays it in shade-intolerant species. AMERICAN JOURNAL OF BOTANY 2023; 110:1-11. [PMID: 36696584 DOI: 10.1002/ajb2.16129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Revised: 12/16/2022] [Accepted: 12/16/2022] [Indexed: 05/11/2023]
Abstract
PREMISE Climate change may lead to C stress (negative C balance) in trees. Because nonstructural carbohydrates (NSC) are required during metabolic reactivation in the spring, C stress might delay budbreak timing. This effect is expected to be greater in shade-intolerant than in shade-tolerant species, owing to the faster C economy in the shade-intolerant. METHODS We experimentally induced C stress in saplings of six temperate tree species that differed in their light requirements by exposing them to either full light or shade from summer to spring, then recorded the date of first budbreak for the individuals. Because the levels of C reserves that represent effective C stress may differ among species, we estimated the degree of C stress by recording survival during the experiment and measuring whole-sapling NSC concentrations after budbreak. RESULTS Shade reduced NSC concentrations and increased the sugar fraction in the NSC in all species. In the shade, shade-intolerant species had higher mortality and generally lower NSC concentrations than the shade-tolerant species, indicating a trend for more severe C stress in species with faster C economy. In shade-intolerant species, budbreak started earlier and proceeded faster in full light than in shade, but in shade-tolerant species budbreak was delayed in full light. The effects of the light environments on budbreak were not greater in shade-intolerant than in shade-tolerant species. CONCLUSIONS Our study reveals a correspondence between budbreak responses to light and the light requirements of the species. This finding confirms that C metabolism has a significant role in triggering budbreak and demonstrates that whether C stress accelerates or delays budbreak depends on the species' light requirements.
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Affiliation(s)
- Frida I Piper
- Instituto de Ciencias Biológicas (ICB), Universidad de Talca, Campus Lircay, Talca, 3460000, Chile
- Instituto de Ecología y Biodiversidad (IEB), Chile. Victoria 631, Barrio Universitario, Concepción, Chile
- Millenium Nucleus of Patagonian Limit of Life (LiLi), Universidad de Talca, Chile
| | - Alex Fajardo
- Instituto de Investigación Interdisciplinaria (I3), Vicerrectoría Académica, Universidad de Talca, Campus Lircay, Talca, 3460000, Chile
- Instituto de Ecología y Biodiversidad (IEB), Chile. Victoria 631, Barrio Universitario, Concepción, Chile
- Millenium Nucleus of Patagonian Limit of Life (LiLi), Universidad de Talca, Chile
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Asefa M, Worthy SJ, Cao M, Song X, Lozano YM, Yang J. Above- and below-ground plant traits are not consistent in response to drought and competition treatments. ANNALS OF BOTANY 2022; 130:939-950. [PMID: 36001733 PMCID: PMC9851322 DOI: 10.1093/aob/mcac108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Accepted: 08/19/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND AND AIMS Our understanding of plant responses to biotic and abiotic drivers is largely based on above-ground plant traits, with little focus on below-ground traits despite their key role in water and nutrient uptake. Here, we aimed to understand the extent to which above- and below-ground traits are co-ordinated, and how these traits respond to soil moisture gradients and plant intraspecific competition. METHODS We chose seedlings of five tropical tree species and grew them in a greenhouse for 16 weeks under a soil moisture gradient [low (drought), medium and high (well-watered) moisture levels] with and without intraspecific competition. At harvest, we measured nine above- and five below-ground traits of all seedlings based on standard protocols. KEY RESULTS In response to the soil moisture gradient, above-ground traits are found to be consistent with the leaf economics spectrum, whereas below-ground traits are inconsistent with the root economics spectrum. We found high specific leaf area and total leaf area in well-watered conditions, while high leaf dry matter content, leaf thickness and stem dry matter content were observed in drought conditions. However, below-ground traits showed contrasting patterns, with high specific root length but low root branching index in the low water treatment. The correlations between above- and below-ground traits across the soil moisture gradient were variable, i.e. specific leaf area was positively correlated with specific root length, while it was negatively correlated with root average diameter across moisture levels. However, leaf dry matter content was unexpectedly positively correlated with both specific root length and root branching index. Intraspecific competition has influenced both above- and below-ground traits, but interacted with soil moisture to affect only below-ground traits. Consistent with functional equilibrium theory, more biomass was allocated to roots under drought conditions, and to leaves under sufficient soil moisture conditions. CONCLUSIONS Our results indicate that the response of below-ground traits to plant intraspecific competition and soil moisture conditions may not be inferred using above-ground traits, suggesting that multiple resource use axes are needed to understand plant ecological strategies. Lack of consistent leaf-root trait correlations across the soil moisture gradient highlight the multidimensionality of plant trait relationships which needs more exploration.
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Affiliation(s)
- Mengesha Asefa
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, 666303, China
- Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Mengla, 666303, China
- Department of Biology, College of Natural and Computational Sciences, University of Gondar, Gondar, 196, Ethiopia
| | - Samantha J Worthy
- Department of Evolution and Ecology, University of California, Davis, CA, USA
| | - Min Cao
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, 666303, China
| | - Xiaoyang Song
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, 666303, China
- Center of Conservation Biology, Core Botanical Gardens, Chinese Academy of Sciences, Mengla, 666303, China
| | - Yudi M Lozano
- Freie Universität Berlin, Institute of Biology, Plant Ecology, D-14195 Berlin, Germany
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), D-14195 Berlin, Germany
| | - Jie Yang
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, 666303, China
- Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Mengla, 666303, China
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