1
|
Penha D, Brum M, Alves LF, Domingues TF, Meneses A, Branches R, Restrepo-Coupe N, Oliveira RS, Moura JMS, Pequeno PACLA, Prohaska N, Saleska SR. Preserving isohydricity: vertical environmental variability explains Amazon forest water-use strategies. TREE PHYSIOLOGY 2024; 44:tpae088. [PMID: 39041710 DOI: 10.1093/treephys/tpae088] [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: 01/10/2024] [Revised: 07/07/2024] [Accepted: 07/18/2024] [Indexed: 07/24/2024]
Abstract
Increases in hydrological extremes, including drought, are expected for Amazon forests. A fundamental challenge for predicting forest responses lies in identifying ecological strategies which underlie such responses. Characterization of species-specific hydraulic strategies for regulating water-use, thought to be arrayed along an 'isohydric-anisohydric' spectrum, is a widely used approach. However, recent studies have questioned the usefulness of this classification scheme, because its metrics are strongly influenced by environments, and hence can lead to divergent classifications even within the same species. Here, we propose an alternative approach positing that individual hydraulic regulation strategies emerge from the interaction of environments with traits. Specifically, we hypothesize that the vertical forest profile represents a key gradient in drought-related environments (atmospheric vapor pressure deficit, soil water availability) that drives divergent tree water-use strategies for coordinated regulation of stomatal conductance (gs) and leaf water potentials (ΨL) with tree rooting depth, a proxy for water availability. Testing this hypothesis in a seasonal eastern Amazon forest in Brazil, we found that hydraulic strategies indeed depend on height-associated environments. Upper canopy trees, experiencing high vapor pressure deficit (VPD), but stable soil water access through deep rooting, exhibited isohydric strategies, defined by little seasonal change in the diurnal pattern of gs and steady seasonal minimum ΨL. In contrast, understory trees, exposed to less variable VPD but highly variable soil water availability, exhibited anisohydric strategies, with fluctuations in diurnal gs that increased in the dry season along with increasing variation in ΨL. Our finding that canopy height structures the coordination between drought-related environmental stressors and hydraulic traits provides a basis for preserving the applicability of the isohydric-to-anisohydric spectrum, which we show here may consistently emerge from environmental context. Our work highlights the importance of understanding how environmental heterogeneity structures forest responses to climate change, providing a mechanistic basis for improving models of tropical ecosystems.
Collapse
Affiliation(s)
- Deliane Penha
- Instituto de Biodiversidade e Florestas, Programa de Pós-Graduação Sociedade, Natureza e Desenvolvimento, Universidade Federal do Oeste do Pará, Vera Paz, s/n, Salé, Santarém, Pará, 68040-255, Brazil
- Instituto de Engenharia e Geociências, Programa de Pós-Graduação em Recursos Naturais da Amazônia, Universidade Federal do Oeste do Pará, Vera Paz, s/n, Salé, Santarém, Pará, 68040-255, Brazil
| | - Mauro Brum
- Department of Ecology and Evolutionary Biology, University of Arizona, 1200 E University Blvd, Tucson, AZ 85721, United States
- Departamento de Biologia Vegetal, Instituto de Biologia, CP 6109, Universidade Estadual de Campinas (UNICAMP), Barão Geraldo, Campinas SP 13083-970, Brazil
| | - Luciana F Alves
- Center for Tropical Research, Institute of the Environment and Sustainability, University of California, Los Angeles, 619 Charles E. Young Drive East, La Kretz Hall, Suite 300, Box 951496, Los Angeles, CA 90095-1496, United States
| | - Tomas F Domingues
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Av. Bandeirantes, 3900, Monte Alegre, Ribeirão Preto, SP 14040-901, Brazil
| | - Anderson Meneses
- Instituto de Biodiversidade e Florestas, Programa de Pós-Graduação Sociedade, Natureza e Desenvolvimento, Universidade Federal do Oeste do Pará, Vera Paz, s/n, Salé, Santarém, Pará, 68040-255, Brazil
- Instituto de Engenharia e Geociências, Programa de Pós-Graduação em Recursos Naturais da Amazônia, Universidade Federal do Oeste do Pará, Vera Paz, s/n, Salé, Santarém, Pará, 68040-255, Brazil
- Instituto de Engenharia e Geociências, Laboratório de Inteligência Computacional, Universidade Federal do Oeste do Pará, Vera Paz, s/n, Salé, Santarém, Pará, 68040-255, Brazil
| | - Rardiles Branches
- Programa de Pós-Graduação em Meteorologia, Instituto Nacional de Pesquisas Espaciais, Rodovia Presidente Dutra, km 40, Cachoeira Paulista, São Paulo 12630-000, Brazil
| | - Natalia Restrepo-Coupe
- Department of Ecology and Evolutionary Biology, University of Arizona, 1200 E University Blvd, Tucson, AZ 85721, United States
| | - Rafael S Oliveira
- Departamento de Biologia Vegetal, Instituto de Biologia, CP 6109, Universidade Estadual de Campinas (UNICAMP), Barão Geraldo, Campinas SP 13083-970, Brazil
| | - José Mauro S Moura
- Instituto de Engenharia e Geociências, Programa de Pós-Graduação em Recursos Naturais da Amazônia, Universidade Federal do Oeste do Pará, Vera Paz, s/n, Salé, Santarém, Pará, 68040-255, Brazil
- Interdisciplinary and Intercultural Training Institute, Federal University of Western Para, Vera Paz, s/n, Salé, Santarém, Pará, 68040-255, Brazil
| | - Pedro A C L Aurélio Pequeno
- Programa de Pós-graduação em Recursos Naturais (PRONAT), Universidade Federal de Roraima, Av. Cap. Ene Garcez, 2413, Aeroporto, Roraima, Boa Vista, 69310-000, Brazil
| | - Neill Prohaska
- Department of Ecology and Evolutionary Biology, University of Arizona, 1200 E University Blvd, Tucson, AZ 85721, United States
| | - Scott R Saleska
- Department of Ecology and Evolutionary Biology, University of Arizona, 1200 E University Blvd, Tucson, AZ 85721, United States
| |
Collapse
|
2
|
Ziegler C, Cochard H, Stahl C, Foltzer L, Gérard B, Goret JY, Heuret P, Levionnois S, Maillard P, Bonal D, Coste S. Residual water losses mediate the trade-off between growth and drought survival across saplings of 12 tropical rainforest tree species with contrasting hydraulic strategies. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:4128-4147. [PMID: 38613495 DOI: 10.1093/jxb/erae159] [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: 07/31/2023] [Accepted: 04/12/2024] [Indexed: 04/15/2024]
Abstract
Knowledge of the physiological mechanisms underlying species vulnerability to drought is critical for better understanding patterns of tree mortality. Investigating plant adaptive strategies to drought should thus help to fill this knowledge gap, especially in tropical rainforests exhibiting high functional diversity. In a semi-controlled drought experiment using 12 rainforest tree species, we investigated the diversity in hydraulic strategies and whether they determined the ability of saplings to use stored non-structural carbohydrates during an extreme imposed drought. We further explored the importance of water- and carbon-use strategies in relation to drought survival through a modelling approach. Hydraulic strategies varied considerably across species with a continuum between dehydration tolerance and avoidance. During dehydration leading to hydraulic failure and irrespective of hydraulic strategies, species showed strong declines in whole-plant starch concentrations and maintenance, or even increases in soluble sugar concentrations, potentially favouring osmotic adjustments. Residual water losses mediated the trade-off between time to hydraulic failure and growth, indicating that dehydration avoidance is an effective drought-survival strategy linked to the 'fast-slow' continuum of plant performance at the sapling stage. Further investigations on residual water losses may be key to understanding the response of tropical rainforest tree communities to climate change.
Collapse
Affiliation(s)
- Camille Ziegler
- UMR EcoFoG, AgroParisTech, CIRAD, CNRS, INRAE, Université des Antilles, Université de Guyane, 97310 Kourou, France
- Université de Lorraine, AgroParisTech, INRAE, UMR SILVA, 54000 Nancy, France
| | - Hervé Cochard
- Université Clermont-Auvergne, INRAE, PIAF, 63000 Clermont-Ferrand, France
| | - Clément Stahl
- UMR EcoFoG, AgroParisTech, CIRAD, CNRS, INRAE, Université des Antilles, Université de Guyane, 97310 Kourou, France
| | - Louis Foltzer
- Université de Lorraine, AgroParisTech, INRAE, UMR SILVA, 54000 Nancy, France
| | - Bastien Gérard
- Université de Lorraine, AgroParisTech, INRAE, UMR SILVA, 54000 Nancy, France
| | - Jean-Yves Goret
- UMR EcoFoG, AgroParisTech, CIRAD, CNRS, INRAE, Université des Antilles, Université de Guyane, 97310 Kourou, France
| | - Patrick Heuret
- UMR EcoFoG, AgroParisTech, CIRAD, CNRS, INRAE, Université des Antilles, Université de Guyane, 97310 Kourou, France
- AMAP, Univ. Montpellier, CIRAD, CNRS, INRAE, IRD, 34000 Montpellier, France
| | - Sébastien Levionnois
- UMR EcoFoG, AgroParisTech, CIRAD, CNRS, INRAE, Université des Antilles, Université de Guyane, 97310 Kourou, France
- AMAP, Univ. Montpellier, CIRAD, CNRS, INRAE, IRD, 34000 Montpellier, France
| | - Pascale Maillard
- Université de Lorraine, AgroParisTech, INRAE, UMR SILVA, 54000 Nancy, France
| | - Damien Bonal
- Université de Lorraine, AgroParisTech, INRAE, UMR SILVA, 54000 Nancy, France
| | - Sabrina Coste
- UMR EcoFoG, AgroParisTech, CIRAD, CNRS, INRAE, Université des Antilles, Université de Guyane, 97310 Kourou, France
| |
Collapse
|
3
|
Song C, Fu Y, Zhu S, Xu W, Ye Q, Yuan W. Linkages between stem vulnerability curves and tree demography and their implications for plant physiological modeling. TREE PHYSIOLOGY 2024; 44:tpae078. [PMID: 38959856 DOI: 10.1093/treephys/tpae078] [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: 01/05/2024] [Revised: 06/22/2024] [Accepted: 07/01/2024] [Indexed: 07/05/2024]
Abstract
Vulnerability curves (VCs) have been measured extensively to describe the differences in plant vulnerability to cavitation. Although the roles of hydraulic conductivity (Ks,max) and hydraulic safety (P50, embolism resistance), both of which are parameters of VCs ('sigmoidal' type), in tree demography have been evaluated across different forests, the direct linkages between VCs and tree demography are rarely explored. In this study, we combined measured VCs and plot data of 16 tree species in Panamanian seasonal tropical forests to investigate the connections between VCs and tree mortality, recruitment and growth. We found that the mortality and recruitment rates of evergreen species were most significantly positively correlated with P50. However, the mortality and recruitment rates of deciduous species only exhibited significant positive correlations with parameter a, which describes the steepness of VCs and indicates the sensitivity of conductivity loss with water potential decline, but is often neglected. These differences among evergreen and deciduous species may contribute to the poor performance of existing quantitative relationships (such as the fitting relationships for all 16 species) in capturing tree mortality and recruitment dynamics. Additionally, evergreen species presented a significant positive relationship between relative growth rate (RGR) and Ks,max, while deciduous species did not display such relationship. The RGR of both evergreen and deciduous species also displayed no significant correlations with P50 and a. Further analysis demonstrated that species with steeper VCs tended to have high mortality and recruitment rates, while species with flatter VCs were usually those with low mortality and recruitment rates. Our results highlight the important role of parameter a in tree demography, especially for deciduous species. Given that VC is a key component of plant hydraulic models, integrating measured VC rather than optimizing its parameters will help improve the ability to simulate and predict forest response to water availability.
Collapse
Affiliation(s)
- Chaoqing Song
- School of Atmospheric Sciences, Guangdong Province Data Center of Terrestrial and Marine Ecosystems Carbon Cycle, Sun Yat-Sen University, Daxue Road, Gaoxin District, Zhuhai, 519082, Guangdong, China
| | - Yangyang Fu
- School of Atmospheric Sciences, Guangdong Province Data Center of Terrestrial and Marine Ecosystems Carbon Cycle, Sun Yat-Sen University, Daxue Road, Gaoxin District, Zhuhai, 519082, Guangdong, China
| | - Shidan Zhu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi Key Laboratory of Forest Ecology and Conservation, Guangxi University, Daxuedong Road 100, Xixiangtang District, Nanning, 530004, Guangxi, China
| | - Wenfang Xu
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Xingke Road 723, Tianhe District, Guangzhou, 510650, Guangdong, China
| | - Qing Ye
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Xingke Road 723, Tianhe District, Guangzhou, 510650, Guangdong, China
| | - Wenping Yuan
- Institute of Carbon Neutrality, Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Zhongguancun North Street 100, Haidian District, Beijing, 100871, China
| |
Collapse
|
4
|
Gauthey A, Bachofen C, Chin A, Cochard H, Gisler J, Mas E, Meusburger K, Peters RL, Schaub M, Tunas A, Zweifel R, Grossiord C. Twenty years of irrigation acclimation is driven by denser canopies and not by plasticity in twig- and needle-level hydraulics in a Pinus sylvestris forest. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:3141-3152. [PMID: 38375924 PMCID: PMC11103111 DOI: 10.1093/jxb/erae066] [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: 11/09/2023] [Accepted: 02/19/2024] [Indexed: 02/21/2024]
Abstract
Climate change is predicted to increase atmospheric vapor pressure deficit, exacerbating soil drought, and thus enhancing tree evaporative demand and mortality. Yet, few studies have addressed the longer-term drought acclimation strategy of trees, particularly the importance of morphological versus hydraulic plasticity. Using a long-term (20 years) irrigation experiment in a natural forest, we investigated the acclimation of Scots pine (Pinus sylvestris) morpho-anatomical traits (stomatal anatomy and crown density) and hydraulic traits (leaf water potential, vulnerability to cavitation (Ψ50), specific hydraulic conductivity (Ks), and tree water deficit) to prolonged changes in soil moisture. We found that low water availability reduced twig water potential and increased tree water deficit during the growing season. Still, the trees showed limited adjustments in most branch-level hydraulic traits (Ψ50 and Ks) and needle anatomy. In contrast, trees acclimated to prolonged irrigation by increasing their crown density and hence the canopy water demand. This study demonstrates that despite substantial canopy adjustments, P. sylvestris may be vulnerable to extreme droughts because of limited adjustment potential in its hydraulic system. While sparser canopies reduce water demand, such shifts take decades to occur under chronic water deficits and might not mitigate short-term extreme drought events.
Collapse
Affiliation(s)
- Alice Gauthey
- Plant Ecology Research Laboratory PERL, School of Architecture, Civil and Environmental Engineering, EPFL, CH-1015, Lausanne, Switzerland
- Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, CH-8903, Birmensdorf, Switzerland
| | - Christoph Bachofen
- Plant Ecology Research Laboratory PERL, School of Architecture, Civil and Environmental Engineering, EPFL, CH-1015, Lausanne, Switzerland
- Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, CH-8903, Birmensdorf, Switzerland
| | - Alana Chin
- Plant Ecology Group, Institute for Integrative Biology, ETH-Zürich, Zürich, Switzerland
| | - Hervé Cochard
- INRAE, PIAF, Université Clermont-Auvergne, Clermont-Ferrand, France
| | - Jonas Gisler
- Forest Dynamics Research Unit, Swiss Federal Institute for Forest, Snow and Landscape WSL, CH-8903, Birmensdorf, Switzerland
| | - Eugénie Mas
- Plant Ecology Research Laboratory PERL, School of Architecture, Civil and Environmental Engineering, EPFL, CH-1015, Lausanne, Switzerland
- Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, CH-8903, Birmensdorf, Switzerland
| | - Katrin Meusburger
- Forest Soils and Biochemistry, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, CH-8903, Birmensdorf, Switzerland
| | - Richard L Peters
- Physiological Plant Ecology, Department of Environmental Sciences, University of Basel, Schönbeinstrasse 6, CH-4056, Basel, Switzerland
| | - Marcus Schaub
- Forest Dynamics Research Unit, Swiss Federal Institute for Forest, Snow and Landscape WSL, CH-8903, Birmensdorf, Switzerland
| | - Alex Tunas
- Plant Ecology Research Laboratory PERL, School of Architecture, Civil and Environmental Engineering, EPFL, CH-1015, Lausanne, Switzerland
- Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, CH-8903, Birmensdorf, Switzerland
- Department of Ecology, University of Innsbruck, Sternwartestrasse 15, A-6020, Innsbruck, Austria
| | - Roman Zweifel
- Forest Dynamics Research Unit, Swiss Federal Institute for Forest, Snow and Landscape WSL, CH-8903, Birmensdorf, Switzerland
| | - Charlotte Grossiord
- Plant Ecology Research Laboratory PERL, School of Architecture, Civil and Environmental Engineering, EPFL, CH-1015, Lausanne, Switzerland
- Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, CH-8903, Birmensdorf, Switzerland
| |
Collapse
|
5
|
Wittemann M, Mujawamariya M, Ntirugulirwa B, Uwizeye FK, Zibera E, Manzi OJL, Nsabimana D, Wallin G, Uddling J. Plasticity and implications of water-use traits in contrasting tropical tree species under climate change. PHYSIOLOGIA PLANTARUM 2024; 176:e14326. [PMID: 38708565 DOI: 10.1111/ppl.14326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Accepted: 04/12/2024] [Indexed: 05/07/2024]
Abstract
Plants face a trade-off between hydraulic safety and growth, leading to a range of water-use strategies in different species. However, little is known about such strategies in tropical trees and whether different water-use traits can acclimate to warming. We studied five water-use traits in 20 tropical tree species grown at three different altitudes in Rwanda (RwandaTREE): stomatal conductance (gs), leaf minimum conductance (gmin), plant hydraulic conductance (Kplant), leaf osmotic potential (ψo) and net defoliation during drought. We also explored the links between these traits and growth and mortality data. Late successional (LS) species had low Kplant, gs and gmin and, thus, low water loss, while low ψo helped improve leaf water status during drought. Early successional (ES) species, on the contrary, used more water during both moist and dry conditions and exhibited pronounced drought defoliation. The ES strategy was associated with lower mortality and more pronounced growth enhancement at the warmer sites compared to LS species. While Kplant and gmin showed downward acclimation in warmer climates, ψo did not acclimate and gs measured at prevailing temperature did not change. Due to distinctly different water use strategies between successional groups, ES species may be better equipped for a warmer climate as long as defoliation can bridge drought periods.
Collapse
Affiliation(s)
- Maria Wittemann
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Myriam Mujawamariya
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
- Department of Biology, College of Science and Technology, University of Rwanda, Kigali, Rwanda
| | - Bonaventure Ntirugulirwa
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
- Department of Biology, College of Science and Technology, University of Rwanda, Kigali, Rwanda
- Rwanda Agriculture and Animal Resources Development Board (RAB), Kigali, Rwanda
- Rwanda Forestry Authority, Muhanga, Rwanda
| | - Felicien K Uwizeye
- School of Forestry and Biodiversity and Biological Sciences, College of Agriculture, Animal Sciences and Veterinary Medicine, University of Rwanda, Musanze, Rwanda
| | - Etienne Zibera
- School of Forestry and Biodiversity and Biological Sciences, College of Agriculture, Animal Sciences and Veterinary Medicine, University of Rwanda, Musanze, Rwanda
| | - Olivier Jean Leonce Manzi
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
- Integrated Polytechnic Regional College-Kitabi, Rwanda Polytechnic, Huye, Rwanda
| | - Donat Nsabimana
- School of Forestry and Biodiversity and Biological Sciences, College of Agriculture, Animal Sciences and Veterinary Medicine, University of Rwanda, Musanze, Rwanda
| | - Göran Wallin
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Johan Uddling
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| |
Collapse
|
6
|
Duan H, Shao C, Zhao N, Wang D, Resco de Dios V, Tissue DT. The role of leaf superoxide dismutase and proline on intra-specific photosynthesis recovery of Schima superba following drought. Sci Rep 2024; 14:8824. [PMID: 38627563 PMCID: PMC11021533 DOI: 10.1038/s41598-024-59467-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Accepted: 04/11/2024] [Indexed: 04/19/2024] Open
Abstract
Understanding the physiological and biochemical responses of tree seedlings under extreme drought stress, along with recovery during rewatering, and potential intra-species differences, will allow us to more accurately predict forest responses under future climate change. Here, we selected seedlings from four provenances (AH (Anhui), JX (Jiangxi), HN (Hunan) and GX (Guangxi)) of Schima superba and carried out a simulated drought-rewatering experiment in a field-based rain-out shelter. Seedlings were progressively dried until they reached 50% and 88% loss of xylem hydraulic conductivity (PLC) (i.e. P50 and P88), respectively, before they were rehydrated and maintained at field capacity for 30 days. Leaf photosynthesis (Asat), water status, activity of superoxide dismutase (SOD), and proline (Pro) concentration were monitored and their associations were determined. Increasing drought significantly reduced Asat, relative water content (RWC) and SOD activity in all provenances, and Pro concentration was increased to improve water retention; all four provenances exhibited similar response patterns, associated with similar leaf ultrastructure at pre-drought. Upon rewatering, physiological and biochemical traits were restored to well-watered control values in P50-stressed seedlings. In P88-stressed seedlings, Pro was restored to control values, while SOD was not fully recovered. The recovery pattern differed partially among provenances. There was a progression of recovery following watering, with RWC firstly recovered, followed by SOD and Pro, and then Asat, but with significant associations among these traits. Collectively, the intra-specific differences of S. superba seedlings in recovery of physiology and biochemistry following rewatering highlight the need to consider variations within a given tree species coping with future more frequent drought stress.
Collapse
Affiliation(s)
- Honglang Duan
- Institute for Forest Resources & Environment of Guizhou, College of Forestry, Guizhou University, Guiyang, 550025, China.
- Jiangxi Provincial Key Laboratory for Restoration of Degraded Ecosystems & Watershed Ecohydrology, Nanchang Institute of Technology, Nanchang, 330099, China.
| | - Changchang Shao
- Institute for Forest Resources & Environment of Guizhou, College of Forestry, Guizhou University, Guiyang, 550025, China
| | - Nan Zhao
- Jiangxi Provincial Key Laboratory for Restoration of Degraded Ecosystems & Watershed Ecohydrology, Nanchang Institute of Technology, Nanchang, 330099, China
| | - Defu Wang
- Research Center of Sichuan Old Revolutionary Areas Development, Sichuan University of Arts and Science, Dazhou, 635000, China
| | - Víctor Resco de Dios
- Department of Crop and Forest Sciences, University of Lleida, 25198, Lleida, Spain
| | - David T Tissue
- Hawkesbury Institute for the Environment, Hawkesbury Campus, Western Sydney University, Richmond, NSW, 2753, Australia
- Global Centre for Land-Based Innovation, Hawkesbury Campus, Western Sydney University, Richmond, NSW, 2753, Australia
| |
Collapse
|
7
|
O'Keefe K, Nippert JB, Keen RM, McCulloh KA. Contrasting shrub and grass hydraulic responses to experimental drought. Oecologia 2024; 204:931-941. [PMID: 38607552 DOI: 10.1007/s00442-024-05543-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 03/07/2024] [Indexed: 04/13/2024]
Abstract
Whole-plant hydraulics provide important information about responses to water limitation and can be used to understand how plant communities may change in a drier climate when measured on multiple species. Here, we measured above- and belowground hydraulic traits in Cornus drummondii, an encroaching shrub within North American tallgrass prairies, and Andropogon gerardii, a dominant C4 grass, to assess the potential hydraulic responses to future drought as this region undergoes woody expansion. Shelters that reduced precipitation by 50% and 0% were built over shrubs and grasses growing in sites that are burned at 1-year and 4-year frequencies. We then measured aboveground (Kshoot), belowground (Kroot), and whole-plant maximum hydraulic conductance (Kplant) in C. drummondii and Kroot in A. gerardii. We also measured vulnerability to embolism (P50) in C. drummondii stems. Overall, we show that: (1) A. gerardii had substantially greater Kroot than C. drummondii; (2) belowground hydraulic functioning was linked with aboveground processes; (3) above- and belowground C. drummondii hydraulics were not negatively impacted by the rainfall reductions imposed here. These results suggest that a multi-year drought will not ameliorate rates of woody expansion and highlight key differences in aboveground and belowground hydraulics for dominant species within the same ecosystem.
Collapse
Affiliation(s)
- Kimberly O'Keefe
- Department of Biological Sciences, St. Edward's University, Austin, TX, 78704, USA.
- Department of Botany, University of Wisconsin, Madison, WI, 53706, USA.
| | - Jesse B Nippert
- Division of Biology, Kansas State University, Manhattan, KS, 66506, USA
| | - Rachel M Keen
- Division of Biology, Kansas State University, Manhattan, KS, 66506, USA
- Department of Ecology and Evolutionary Biology, Kansas Biological Survey, The University of Kansas, Lawrence, KS, 66047, USA
| | | |
Collapse
|
8
|
Beckett HAA, Bryant C, Neeman T, Mencuccini M, Ball MC. Plasticity in branch water relations and stem hydraulic vulnerability enhances hydraulic safety in mangroves growing along a salinity gradient. PLANT, CELL & ENVIRONMENT 2024; 47:854-870. [PMID: 37975319 DOI: 10.1111/pce.14764] [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: 08/09/2023] [Revised: 10/05/2023] [Accepted: 10/31/2023] [Indexed: 11/19/2023]
Abstract
Coping with water stress depends on maintaining cellular function and hydraulic conductance. Yet measurements of vulnerability to drought and salinity do not often focus on capacitance in branch organs that buffer hydraulic function during water stress. The relationships between branch water relations, stem hydraulic vulnerability and stem anatomy were investigated in two co-occurring mangroves Aegiceras corniculatum and Rhizophora stylosa growing at low and high salinity. The dynamics of branch water release acted to conserve water content in the stem at the expense of the foliage during extended drying. Hydraulic redistribution from the foliage to the stem increased stem relative water content by up to 21%. The water potentials at which 12% and 50% loss of stem hydraulic conductivity occurred decreased by ~1.7 MPa in both species between low and high salinity sites. These coordinated tissue adjustments increased hydraulic safety despite declining turgor safety margins at higher salinity sites. Our results highlight the complex interplay of plasticity in organ-level water relations with hydraulic vulnerability in the maintenance of stem hydraulic function in mangroves distributed along salinity gradients. These results emphasise the importance of combining water relations and hydraulic vulnerability parameters to understand vulnerability to water stress across the whole plant.
Collapse
Affiliation(s)
- Holly A A Beckett
- Plant Science Division, Research School of Biology, Australian National University, Canberra, Australia
| | - Callum Bryant
- Plant Science Division, Research School of Biology, Australian National University, Canberra, Australia
| | - Teresa Neeman
- Biological Data Science Institute, Australian National University, Canberra, Australia
| | - Maurizio Mencuccini
- Ecological and Forestry Applications Research Centre (CREAF), Barcelona, Bellaterra, Spain
| | - Marilyn C Ball
- Plant Science Division, Research School of Biology, Australian National University, Canberra, Australia
| |
Collapse
|
9
|
Li S, Huang X, Zheng R, Zhang M, Zou Z, Heal KV, Zhou L. Xylem plasticity of root, stem, and branch in Cunninghamia lanceolata under drought stress: implications for whole-plant hydraulic integrity. FRONTIERS IN PLANT SCIENCE 2024; 15:1308360. [PMID: 38439985 PMCID: PMC10910014 DOI: 10.3389/fpls.2024.1308360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 01/19/2024] [Indexed: 03/06/2024]
Abstract
Introduction A better understanding of xylem hydraulic characteristics in trees is critical to elucidate the mechanisms of forest decline and tree mortality from water deficit. As well as temperate forests and forests growing in arid regions, subtropical and tropical forests are also predicted to experience an increased frequency and intensity of climate change-induced drought in the near future. Methods In this study, 1-year-old Cunninghamia lanceolata seedlings (a typical subtropical species in southern China) were selected for a continuous controlled drought pot experiment of 45 days duration. The experimental treatments were non-drought (control), light drought, moderate drought and severe drought stress, which were 80%, 60%, 50%, and 40%, respectively of soil field maximum moisture capacity. Results The hydraulic conductivity, specific conductivity and water potential of roots, stems, and branches of C. lanceolata all decreased with the prolonging of drought in the different drought intensities. The relative decrease in these hydraulic values were greater in roots than in stems and branches, indicating that roots are more sensitive to drought. Root tracheid diameters normally reduce to ensure security of water transport with prolonged drought, whilst the tracheid diameters of stems and branches expand initially to ensure water transport and then decrease to reduce the risk of embolism with continuing drought duration. The pit membrane diameter of roots, stems and branches generally increased to different extents during the 15-45 days drought duration, which is conducive to enhanced radial water transport ability. The tracheid density and pit density of stems generally decreased during drought stress, which decreased water transport efficiency and increased embolism occurrence. Correlation analysis indicated that anatomical plasticity greatly influenced the hydraulic properties, whilst the relationships varied among different organs. In roots, tracheid diameter decreased and tracheid density increased to enhance water transport security; stems and branches may increase tracheid diameter and pit membrane diameter to increase hydraulic conductivity ability, but may increase the occurrence of xylem embolism. Discussion In summary, under drought stress, the xylem anatomical characteristics of C. lanceolata organs were highly plastic to regulate water transport vertically and radially to maintain the trade-off between hydraulic conductivity efficiency and safety.
Collapse
Affiliation(s)
- Shubin Li
- Forestry College, Fujian Agriculture and Forestry University, Fuzhou, China
- Chinese Fir Engineering Technology Research Center of the State Forestry and Grassland Administration, Fuzhou, China
| | - Xiaoyan Huang
- Forestry College, Fujian Agriculture and Forestry University, Fuzhou, China
- Chinese Fir Engineering Technology Research Center of the State Forestry and Grassland Administration, Fuzhou, China
| | - Ruping Zheng
- Forestry College, Fujian Agriculture and Forestry University, Fuzhou, China
- Huaying Forestry Development Center, Huaying, China
| | - Maxiao Zhang
- Chinese Fir Engineering Technology Research Center of the State Forestry and Grassland Administration, Fuzhou, China
- College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Zhiguang Zou
- Forestry College, Fujian Agriculture and Forestry University, Fuzhou, China
- Chinese Fir Engineering Technology Research Center of the State Forestry and Grassland Administration, Fuzhou, China
| | - Kate V. Heal
- School of Geo Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Lili Zhou
- Chinese Fir Engineering Technology Research Center of the State Forestry and Grassland Administration, Fuzhou, China
- College of Geography and Oceanography, Minjiang University, Fuzhou, China
| |
Collapse
|
10
|
Zhang Z, Wang X, Guo S, Li Z, He M, Zhang Y, Li G, Han X, Yang G. Divergent patterns and drivers of leaf functional traits of Robinia pseudoacacia and Pinus tabulaeformis plantations along a precipitation gradient in the Loess plateau, China. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 348:119318. [PMID: 37857219 DOI: 10.1016/j.jenvman.2023.119318] [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: 07/21/2023] [Revised: 09/30/2023] [Accepted: 10/06/2023] [Indexed: 10/21/2023]
Abstract
Changes in precipitation patterns in arid and semi-arid regions can reshape plant functional traits and significantly affect ecosystem functions. However, the synchronous responses of leaf economical, anatomical, photosynthetic, and biochemical traits to precipitation changes and their driving factors have rarely been investigated, which hinders our understanding of plants' ecological adaptation strategies to drought tolerance in arid areas. Therefore, the leaf traits of two typical plantations (Robinia pseudoacacia, RP and Pinus tabulaeformis, PT) along the precipitation gradient in the Loess Plateau, including economical, anatomical, photosynthetic, and biochemical traits, were investigated in this study. The results show that the leaf photosynthetic traits of RP and PT increase along the precipitation gradient, whereas leaf biochemical traits decrease. The anatomical traits of PT decrease with increasing precipitation, whereas no significant variation was observed for RP. Random Forest analysis show that LNC, LDMC, Chl, and PRO are leaf traits that significantly vary with the precipitation gradient in both plantations. Correlation analysis reveals that the traits coordination of RP is better than that of PT. The LMG model was used to determine driving factors. The results suggest that MAP explains the variation of PT leaf traits better (30.38%-36.78%), whereas SCH and SPH contribute more to the variation of RP leaf traits (20.88%-41.76%). In addition, the piecewise Structural Equation Model shows that the climate and soil physical and chemical properties directly affect the selected leaf functional traits of RP, whereas only the soil chemical properties directly affect the selected leaf functional traits of PT. The results of this study contribute to the understanding of the ecological adaptation of plants to environmental gradients and highlight that correlations among leaf traits should be considered when predicting plant adaptation strategies under future global change scenarios.
Collapse
Affiliation(s)
- Zhenjiao Zhang
- College of Agronomy, Northwest A&F University, Yangling, 712100, Shaanxi, PR China; Shaanxi Engineering Research Center of Circular Agriculture, Yangling, 712100, Shaanxi, PR China
| | - Xing Wang
- College of Agronomy, Northwest A&F University, Yangling, 712100, Shaanxi, PR China; Shaanxi Engineering Research Center of Circular Agriculture, Yangling, 712100, Shaanxi, PR China
| | - Shujuan Guo
- A School of Agricultural Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, PR China.
| | - Zhenxia Li
- College of Agronomy, Northwest A&F University, Yangling, 712100, Shaanxi, PR China; Shaanxi Engineering Research Center of Circular Agriculture, Yangling, 712100, Shaanxi, PR China
| | - Mengfan He
- College of Agronomy, Northwest A&F University, Yangling, 712100, Shaanxi, PR China; Shaanxi Engineering Research Center of Circular Agriculture, Yangling, 712100, Shaanxi, PR China
| | - Yunlong Zhang
- College of Agronomy, Northwest A&F University, Yangling, 712100, Shaanxi, PR China; Shaanxi Engineering Research Center of Circular Agriculture, Yangling, 712100, Shaanxi, PR China
| | - Guixing Li
- College of Agronomy, Northwest A&F University, Yangling, 712100, Shaanxi, PR China; Shaanxi Engineering Research Center of Circular Agriculture, Yangling, 712100, Shaanxi, PR China
| | - Xinhui Han
- College of Agronomy, Northwest A&F University, Yangling, 712100, Shaanxi, PR China; Shaanxi Engineering Research Center of Circular Agriculture, Yangling, 712100, Shaanxi, PR China.
| | - Gaihe Yang
- College of Agronomy, Northwest A&F University, Yangling, 712100, Shaanxi, PR China; Shaanxi Engineering Research Center of Circular Agriculture, Yangling, 712100, Shaanxi, PR China
| |
Collapse
|
11
|
Binks O, Cernusak LA, Liddell M, Bradford M, Coughlin I, Bryant C, Palma AC, Hoffmann L, Alam I, Carle HJ, Rowland L, Oliveira RS, Laurance SGW, Mencuccini M, Meir P. Vapour pressure deficit modulates hydraulic function and structure of tropical rainforests under nonlimiting soil water supply. THE NEW PHYTOLOGIST 2023; 240:1405-1420. [PMID: 37705460 DOI: 10.1111/nph.19257] [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: 03/28/2023] [Accepted: 08/07/2023] [Indexed: 09/15/2023]
Abstract
Atmospheric conditions are expected to become warmer and drier in the future, but little is known about how evaporative demand influences forest structure and function independently from soil moisture availability, and how fast-response variables (such as canopy water potential and stomatal conductance) may mediate longer-term changes in forest structure and function in response to climate change. We used two tropical rainforest sites with different temperatures and vapour pressure deficits (VPD), but nonlimiting soil water supply, to assess the impact of evaporative demand on ecophysiological function and forest structure. Common species between sites allowed us to test the extent to which species composition, relative abundance and intraspecific variability contributed to site-level differences. The highest VPD site had lower midday canopy water potentials, canopy conductance (gc ), annual transpiration, forest stature, and biomass, while the transpiration rate was less sensitive to changes in VPD; it also had different height-diameter allometry (accounting for 51% of the difference in biomass between sites) and higher plot-level wood density. Our findings suggest that increases in VPD, even in the absence of soil water limitation, influence fast-response variables, such as canopy water potentials and gc , potentially leading to longer-term changes in forest stature resulting in reductions in biomass.
Collapse
Affiliation(s)
- Oliver Binks
- CREAF, Cerdanyola del Vallès, Barcelona, 08193, Spain
- Research School of Biology, The Australian National University, Canberra, 2601, ACT, Australia
| | - Lucas A Cernusak
- Centre for Tropical Environmental and Sustainability Science, College of Science and Engineering, James Cook University, Cairns, 4878, Qld, Australia
| | - Michael Liddell
- Centre for Tropical Environmental and Sustainability Science, College of Science and Engineering, James Cook University, Cairns, 4878, Qld, Australia
| | - Matt Bradford
- CSIRO Land and Water, Atherton, 4883, Qld, Australia
| | - Ingrid Coughlin
- Research School of Biology, The Australian National University, Canberra, 2601, ACT, Australia
| | - Callum Bryant
- Research School of Biology, The Australian National University, Canberra, 2601, ACT, Australia
| | - Ana C Palma
- Centre for Tropical Environmental and Sustainability Science, College of Science and Engineering, James Cook University, Cairns, 4878, Qld, Australia
| | - Luke Hoffmann
- Centre for Tropical Environmental and Sustainability Science, College of Science and Engineering, James Cook University, Cairns, 4878, Qld, Australia
| | - Iftakharul Alam
- Centre for Tropical Environmental and Sustainability Science, College of Science and Engineering, James Cook University, Cairns, 4878, Qld, Australia
| | - Hannah J Carle
- Research School of Biology, The Australian National University, Canberra, 2601, ACT, Australia
| | - Lucy Rowland
- Geography, Faculty of Environment Science and Economy, University of Exeter, Laver Building, Exeter, EX4 4QE, UK
| | - Rafael S Oliveira
- Departamento de Biologia Vegetal, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, 13083-970, SP, Brazil
| | - Susan G W Laurance
- Centre for Tropical Environmental and Sustainability Science, College of Science and Engineering, James Cook University, Cairns, 4878, Qld, Australia
| | | | - Patrick Meir
- Research School of Biology, The Australian National University, Canberra, 2601, ACT, Australia
- School of Geosciences, University of Edinburgh, Edinburgh, EH9 3FF, UK
| |
Collapse
|
12
|
Song HQ, Wang YQ, Yan CL, Zeng WH, Chen YJ, Zhang JL, Liu H, Zhang QM, Zhu SD. Can leaf drought tolerance predict species abundance and its changes in tropical-subtropical forests? TREE PHYSIOLOGY 2023; 43:1319-1325. [PMID: 37154549 DOI: 10.1093/treephys/tpad058] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 04/14/2023] [Accepted: 05/01/2023] [Indexed: 05/10/2023]
Abstract
Climate change has resulted in an increase in drought severity in the species-rich tropical and subtropical forests of southern China. Exploring the spatiotemporal relationship between drought-tolerance trait and tree abundance provides a means to elucidate the impact of droughts on community assembly and dynamics. In this study, we measured the leaf turgor loss point (πtlp) for 399 tree species from three tropical forest plots and three subtropical forest plots. The plot area was 1 ha and tree abundance was calculated as total basal area per hectare according to the nearest community census data. The first aim of this study was to explore πtlp abundance relationships in the six plots across a range of precipitation seasonality. Additionally, three of the six plots (two tropical forests and one subtropical forest) had consecutive community censuses data (12-22 years) and the mortality ratios and abundance year slope of tree species were analyzed. The second aim was to examine whether πtlp is a predictor of tree mortality and abundance changes. Our results showed that tree species with lower (more negative) πtlp were more abundant in the tropical forests with relative high seasonality. However, πtlp was not related to tree abundance in the subtropical forests with low seasonality. Moreover, πtlp was not a good predictor of tree mortality and abundance changes in both humid and dry forests. This study reveals the restricted role of πtlp in predicting the response of forests to increasing droughts under climate change.
Collapse
Affiliation(s)
- Hui-Qing Song
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Forestry, Guangxi University, Nanning 530004, Guangxi, China
| | - Yong-Qiang Wang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Forestry, Guangxi University, Nanning 530004, Guangxi, China
| | - Chao-Long Yan
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Forestry, Guangxi University, Nanning 530004, Guangxi, China
| | - Wen-Hao Zeng
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Forestry, Guangxi University, Nanning 530004, Guangxi, China
| | - Ya-Jun Chen
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, Yunnan, China
| | - Jiao-Lin Zhang
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, Yunnan, China
| | - Hui Liu
- Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, Guangdong, China
| | - Qian-Mei Zhang
- Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, Guangdong, China
- Dinghushan Forest Ecosystem Research Station, South China Botanical Garden, Chinese Academy of Sciences, Zhaoqing 526070, Guangdong, China
| | - Shi-Dan Zhu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Forestry, Guangxi University, Nanning 530004, Guangxi, China
| |
Collapse
|
13
|
Rowland L, Ramírez-Valiente JA, Hartley IP, Mencuccini M. How woody plants adjust above- and below-ground traits in response to sustained drought. THE NEW PHYTOLOGIST 2023. [PMID: 37306017 DOI: 10.1111/nph.19000] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 04/01/2023] [Indexed: 06/13/2023]
Abstract
Future increases in drought severity and frequency are predicted to have substantial impacts on plant function and survival. However, there is considerable uncertainty concerning what drought adjustment is and whether plants can adjust to sustained drought. This review focuses on woody plants and synthesises the evidence for drought adjustment in a selection of key above-ground and below-ground plant traits. We assess whether evaluating the drought adjustment of single traits, or selections of traits that operate on the same plant functional axis (e.g. photosynthetic traits) is sufficient, or whether a multi-trait approach, integrating across multiple axes, is required. We conclude that studies on drought adjustments in woody plants might overestimate the capacity for adjustment to drier environments if spatial studies along gradients are used, without complementary experimental approaches. We provide evidence that drought adjustment is common in above-ground and below-ground traits; however, whether this is adaptive and sufficient to respond to future droughts remains uncertain for most species. To address this uncertainty, we must move towards studying trait integration within and across multiple axes of plant function (e.g. above-ground and below-ground) to gain a holistic view of drought adjustments at the whole-plant scale and how these influence plant survival.
Collapse
Affiliation(s)
- Lucy Rowland
- Geography, Faculty of Environment, Science and Economy, University of Exeter, Exeter, EX4 4RJ, UK
| | | | - Iain P Hartley
- Geography, Faculty of Environment, Science and Economy, University of Exeter, Exeter, EX4 4RJ, UK
| | - Maurizio Mencuccini
- CREAF, Campus de Bellaterra (UAB), Cerdanyola del Vallés, Barcelona, 08193, Spain
- ICREA, Barcelona, 08010, Spain
| |
Collapse
|
14
|
Simioni PF, Emilio T, Giles AL, Viana de Freitas G, Silva Oliveira R, Setime L, Pierre Vitoria A, Pireda S, Vieira da Silva I, Da Cunha M. Anatomical traits related to leaf and branch hydraulic functioning on Amazonian savanna plants. AOB PLANTS 2023; 15:plad018. [PMID: 37214224 PMCID: PMC10198777 DOI: 10.1093/aobpla/plad018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 04/23/2023] [Indexed: 05/24/2023]
Abstract
Amazonian savannas are isolated patches of open habitats found within the extensive matrix of Amazonian tropical forests. There remains limited evidence on how Amazonian plants from savannas differ in the traits related to drought resistance and water loss control. Previous studies have reported several xeromorphic characteristics of Amazonian savanna plants at the leaf and branch levels that are linked to soil, solar radiation, rainfall and seasonality. How anatomical features relate to plant hydraulic functioning in this ecosystem is less known and instrumental if we want to accurately model transitions in trait states between alternative vegetation in Amazonia. In this context, we combined studies of anatomical and hydraulic traits to understand the structure-function relationships of leaf and wood xylem in plants of Amazonian savannas. We measured 22 leaf, wood and hydraulic traits, including embolism resistance (as P50), Hydraulic Safety Margin (HSM) and isotope-based water use efficiency (WUE), for the seven woody species that account for 75% of the biomass of a typical Amazonian savanna on rocky outcrops in the state of Mato Grosso, Brazil. Few anatomical traits are related to hydraulic traits. Our findings showed wide variation exists among the seven species studied here in resistance to embolism, water use efficiency and structural anatomy, suggesting no unique dominant functional plant strategy to occupy an Amazonian savanna. We found wide variation in resistance to embolism (-1.6 ± 0.1 MPa and -5.0 ± 0.5 MPa) with species that are less efficient in water use (e.g. Kielmeyera rubriflora, Macairea radula, Simarouba versicolor, Parkia cachimboensis and Maprounea guianensis) showing higher stomatal conductance potential, supporting xylem functioning with leaf succulence and/or safer wood anatomical structures and that species that are more efficient in water use (e.g. Norantea guianensis and Alchornea discolor) can exhibit riskier hydraulic strategies. Our results provide a deeper understanding of how branch and leaf structural traits combine to allow for different hydraulic strategies among coexisting plants. In Amazonian savannas, this may mean investing in buffering water loss (e.g. succulence) at leaf level or safer structures (e.g. thicker pit membranes) and architectures (e.g. vessel grouping) in their branch xylem.
Collapse
Affiliation(s)
| | - Thaise Emilio
- Programa Nacional de Pós-Doutorado (PNPD), Programa de Pós-Graduação em Ecologia, Instituto de Biologia, UNICAMP, Campinas, Brasil
| | - André L Giles
- Instituo Nacional de Pesquisa da Amazonia (INPA), Manaus, Amazonas, Brasil
- Departamento de Fitotecnia, Centro de Ciências Agrárias, Universidade Federal de Santa Catarina, Florianópolis, Brasil
| | - Gustavo Viana de Freitas
- Laboratório de Ciências Ambientais, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes, RJ, Brasil
| | | | - Lara Setime
- Laboratório de Biologia Celular e Tecidual, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes, RJ, Brasil
| | - Angela Pierre Vitoria
- Laboratório de Ciências Ambientais, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes, RJ, Brasil
| | - Saulo Pireda
- Laboratório de Biologia Celular e Tecidual, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes, RJ, Brasil
| | - Ivone Vieira da Silva
- Laboratório de Biologia Vegetal, Universidade do Estado do Mato Grosso, Alta Floresta, MT, Brasil
| | - Maura Da Cunha
- Laboratório de Biologia Celular e Tecidual, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes, RJ, Brasil
| |
Collapse
|
15
|
Tavares JV, Oliveira RS, Mencuccini M, Signori-Müller C, Pereira L, Diniz FC, Gilpin M, Marca Zevallos MJ, Salas Yupayccana CA, Acosta M, Pérez Mullisaca FM, Barros FDV, Bittencourt P, Jancoski H, Scalon MC, Marimon BS, Oliveras Menor I, Marimon BH, Fancourt M, Chambers-Ostler A, Esquivel-Muelbert A, Rowland L, Meir P, Lola da Costa AC, Nina A, Sanchez JMB, Tintaya JS, Chino RSC, Baca J, Fernandes L, Cumapa ERM, Santos JAR, Teixeira R, Tello L, Ugarteche MTM, Cuellar GA, Martinez F, Araujo-Murakami A, Almeida E, da Cruz WJA, Del Aguila Pasquel J, Aragāo L, Baker TR, de Camargo PB, Brienen R, Castro W, Ribeiro SC, Coelho de Souza F, Cosio EG, Davila Cardozo N, da Costa Silva R, Disney M, Espejo JS, Feldpausch TR, Ferreira L, Giacomin L, Higuchi N, Hirota M, Honorio E, Huaraca Huasco W, Lewis S, Flores Llampazo G, Malhi Y, Monteagudo Mendoza A, Morandi P, Chama Moscoso V, Muscarella R, Penha D, Rocha MC, Rodrigues G, Ruschel AR, Salinas N, Schlickmann M, Silveira M, Talbot J, Vásquez R, Vedovato L, Vieira SA, Phillips OL, Gloor E, Galbraith DR. Basin-wide variation in tree hydraulic safety margins predicts the carbon balance of Amazon forests. Nature 2023; 617:111-117. [PMID: 37100901 PMCID: PMC10156596 DOI: 10.1038/s41586-023-05971-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 03/17/2023] [Indexed: 04/28/2023]
Abstract
Tropical forests face increasing climate risk1,2, yet our ability to predict their response to climate change is limited by poor understanding of their resistance to water stress. Although xylem embolism resistance thresholds (for example, [Formula: see text]50) and hydraulic safety margins (for example, HSM50) are important predictors of drought-induced mortality risk3-5, little is known about how these vary across Earth's largest tropical forest. Here, we present a pan-Amazon, fully standardized hydraulic traits dataset and use it to assess regional variation in drought sensitivity and hydraulic trait ability to predict species distributions and long-term forest biomass accumulation. Parameters [Formula: see text]50 and HSM50 vary markedly across the Amazon and are related to average long-term rainfall characteristics. Both [Formula: see text]50 and HSM50 influence the biogeographical distribution of Amazon tree species. However, HSM50 was the only significant predictor of observed decadal-scale changes in forest biomass. Old-growth forests with wide HSM50 are gaining more biomass than are low HSM50 forests. We propose that this may be associated with a growth-mortality trade-off whereby trees in forests consisting of fast-growing species take greater hydraulic risks and face greater mortality risk. Moreover, in regions of more pronounced climatic change, we find evidence that forests are losing biomass, suggesting that species in these regions may be operating beyond their hydraulic limits. Continued climate change is likely to further reduce HSM50 in the Amazon6,7, with strong implications for the Amazon carbon sink.
Collapse
Affiliation(s)
- Julia Valentim Tavares
- School of Geography, University of Leeds, Leeds, UK.
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden.
| | - Rafael S Oliveira
- Department of Plant Biology, Institute of Biology, University of Campinas, Campinas, Brazil
| | | | - Caroline Signori-Müller
- School of Geography, University of Leeds, Leeds, UK
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
- Department of Plant Biology, Institute of Biology, Programa de Pós Graduação em Biologia Vegetal, University of Campinas, Campinas, Brazil
| | - Luciano Pereira
- Department of Plant Biology, Institute of Biology, University of Campinas, Campinas, Brazil
- Institute of Systematic Botany and Ecology, Ulm University, Ulm, Germany
| | | | | | | | | | - Martin Acosta
- Programa de Pós-Graduação em Ecologia e Manejo de Recursos Naturais, Universidade Federal do Acre, Rio Branco, Brazil
| | | | - Fernanda de V Barros
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
- Department of Plant Biology, Institute of Biology, Programa de Pós Graduação em Ecologia, University of Campinas, Campinas, Brazil
| | - Paulo Bittencourt
- Department of Plant Biology, Institute of Biology, University of Campinas, Campinas, Brazil
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Halina Jancoski
- Departamento de Ciências Biológicas, Universidade do Estado de Mato Grosso (UNEMAT), Nova Xavantina, Brazil
| | - Marina Corrêa Scalon
- Departamento de Ciências Biológicas, Universidade do Estado de Mato Grosso (UNEMAT), Nova Xavantina, Brazil
- Programa de Pós-Graduação em Ecologia e Conservação, Universidade Federal do Paraná, Curitiba, Brazil
| | - Beatriz S Marimon
- Departamento de Ciências Biológicas, Universidade do Estado de Mato Grosso (UNEMAT), Nova Xavantina, Brazil
| | - Imma Oliveras Menor
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, UK
- AMAP (Botanique et Modélisation de l'Architecture des Plantes et des Végétations), CIRAD, CNRS, INRA, IRD, Université de Montpellier, Montpellier, France
| | - Ben Hur Marimon
- Departamento de Ciências Biológicas, Universidade do Estado de Mato Grosso (UNEMAT), Nova Xavantina, Brazil
| | - Max Fancourt
- School of Geography, University of Leeds, Leeds, UK
| | | | - Adriane Esquivel-Muelbert
- School of Geography, University of Birmingham, Birmingham, UK
- Birmingham Institute of Forest Research (BIFoR), Birmingham, UK
| | - Lucy Rowland
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Patrick Meir
- School of Geosciences, University of Edinburgh, Edinburgh, UK
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory, Australia
| | | | - Alex Nina
- Pontificia Universidad Católica del Perú, Lima, Peru
| | | | - Jose S Tintaya
- Universidad Nacional de San Antonio Abad del Cusco, Cusco, Peru
| | | | - Jean Baca
- Universidad Nacional de la Amazonia Peruana, Iquitos, Peru
| | | | - Edwin R M Cumapa
- Instituto de Geociências, Faculdade de Meteorologia, Universidade Federal do Pará, Belém, Brazil
| | | | - Renata Teixeira
- Universidad Nacional de San Antonio Abad del Cusco, Cusco, Peru
| | - Ligia Tello
- Universidad Nacional de la Amazonia Peruana, Iquitos, Peru
| | - Maira T M Ugarteche
- Museo de Historia Natural Noel Kempff Mercado, Santa Cruz de la Sierra, Bolivia
- Universidad Autonoma Gabriel Rene Moreno, Santa Cruz, Bolivia
| | - Gina A Cuellar
- Museo de Historia Natural Noel Kempff Mercado, Santa Cruz de la Sierra, Bolivia
- Universidad Autonoma Gabriel Rene Moreno, Santa Cruz, Bolivia
| | - Franklin Martinez
- Museo de Historia Natural Noel Kempff Mercado, Santa Cruz de la Sierra, Bolivia
- Universidad Autonoma Gabriel Rene Moreno, Santa Cruz, Bolivia
| | - Alejandro Araujo-Murakami
- Museo de Historia Natural Noel Kempff Mercado, Santa Cruz de la Sierra, Bolivia
- Universidad Autonoma Gabriel Rene Moreno, Santa Cruz, Bolivia
| | - Everton Almeida
- Instituto de Biodiversidade e Florestas, Universidade Federal do Oeste do Pará, Santarém, Brazil
| | | | - Jhon Del Aguila Pasquel
- Universidad Nacional de la Amazonia Peruana (UNAP), Iquitos, Peru
- Instituto de Investigaciones de la Amazonia Peruana, Iquitos, Peru
| | - Luís Aragāo
- National Institute for Space Research (INPE), São José dos Campos-SP, Brazil
| | | | | | - Roel Brienen
- School of Geography, University of Leeds, Leeds, UK
| | - Wendeson Castro
- Laboratório de Botânica e Ecologia Vegetal, Universidade Federal do Acre, Rio Branco, Brazil
- SOS Amazônia, Programa Governança e Proteção da Paisagem Verde na Amazônia, Rio Branco-AC, Brazil
| | | | | | - Eric G Cosio
- Sección Química, Pontificia Universidad Católica del Perú, Lima, Peru
| | | | - Richarlly da Costa Silva
- Programa de Pós-Graduação em Ecologia e Manejo de Recursos Naturais, Universidade Federal do Acre, Rio Branco, Brazil
- Instituto Federal de Educação, Ciência e Tecnologia do Acre, Campus Baixada do Sol, Rio Branco, Brazil
| | - Mathias Disney
- Department of Geography, University College London, London, UK
| | - Javier Silva Espejo
- Universidad Nacional de San Antonio Abad del Cusco, Cusco, Peru
- Departamento de Biología, Universidad de La Serena, La Serena, Chile
| | - Ted R Feldpausch
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | | | - Leandro Giacomin
- Departamento de Sistemática e Ecologia, Centro de Ciências Exatas e da Natureza, Universidade Federal da Paraíba, João Pessoa, Brazil
| | - Niro Higuchi
- Instituto Nacional de Pesquisas da Amazônia, Manaus, Brazil
| | - Marina Hirota
- Department of Plant Biology, Institute of Biology, University of Campinas, Campinas, Brazil
- Department of Physics, Federal University of Santa Catarina, Florianópolis, Brazil
| | - Euridice Honorio
- Instituto de Investigaciones de la Amazonia Peruana, Iquitos, Peru
| | - Walter Huaraca Huasco
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, UK
| | - Simon Lewis
- School of Geography, University of Leeds, Leeds, UK
- Department of Geography, University College London, London, UK
| | - Gerardo Flores Llampazo
- Instituto de Investigaciones de la Amazonia Peruana, Iquitos, Peru
- Universidad Nacional Jorge Basadre de Grohmann (UNJBG), Tacna, Peru
| | - Yadvinder Malhi
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, UK
| | - Abel Monteagudo Mendoza
- Universidad Nacional de San Antonio Abad del Cusco, Cusco, Peru
- Jardín Botánico de Missouri, Oxapampa, Peru
| | - Paulo Morandi
- Departamento de Ciências Biológicas, Universidade do Estado de Mato Grosso (UNEMAT), Nova Xavantina, Brazil
| | - Victor Chama Moscoso
- Universidad Nacional de San Antonio Abad del Cusco, Cusco, Peru
- Jardín Botánico de Missouri, Oxapampa, Peru
| | - Robert Muscarella
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Deliane Penha
- Programa de Pós-Graduação em Biodiversidade, Universidade Federal do Oeste do Pará, Santarém, Brazil
| | - Mayda Cecília Rocha
- Instituto de Ciências e Tecnologia das Águas, Universidade Federal do Oeste do Pará, Santarém, Brazil
| | - Gleicy Rodrigues
- Programa de Pós-Graduação em Botânica, Instituto Nacional de Pesquisas da Amazônia, Manaus, Brazil
| | | | - Norma Salinas
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, UK
- Sección Química, Pontificia Universidad Católica del Perú, Lima, Peru
| | - Monique Schlickmann
- Programa de Pós-Graduação em Biodiversidade, Universidade Federal do Oeste do Pará, Santarém, Brazil
| | - Marcos Silveira
- Museu Universitário, Centro de Ciências Biológicas e da Natureza, Universidade Federal do Acre, Rio Branco, Brazil
| | - Joey Talbot
- Institute for Transport Studies, University of Leeds, Leeds, UK
| | | | - Laura Vedovato
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Simone Aparecida Vieira
- Núcleo de Estudos e Pesquisas Ambientais, Universidade Estadual de Campinas, Campinas, Brazil
| | | | | | | |
Collapse
|
16
|
Yao Y, Ciais P, Viovy N, Joetzjer E, Chave J. How drought events during the last century have impacted biomass carbon in Amazonian rainforests. GLOBAL CHANGE BIOLOGY 2023; 29:747-762. [PMID: 36285645 PMCID: PMC10100251 DOI: 10.1111/gcb.16504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 09/27/2022] [Indexed: 06/16/2023]
Abstract
During the last two decades, inventory data show that droughts have reduced biomass carbon sink of the Amazon forest by causing mortality to exceed growth. However, process-based models have struggled to include drought-induced responses of growth and mortality and have not been evaluated against plot data. A process-based model, ORCHIDEE-CAN-NHA, including forest demography with tree cohorts, plant hydraulic architecture and drought-induced tree mortality, was applied over Amazonia rainforests forced by gridded climate fields and rising CO2 from 1901 to 2019. The model reproduced the decelerating signal of net carbon sink and drought sensitivity of aboveground biomass (AGB) growth and mortality observed at forest plots across selected Amazon intact forests for 2005 and 2010. We predicted a larger mortality rate and a more negative sensitivity of the net carbon sink during the 2015/16 El Niño compared with the former droughts. 2015/16 was indeed the most severe drought since 1901 regarding both AGB loss and area experiencing a severe carbon loss. We found that even if climate change did increase mortality, elevated CO2 contributed to balance the biomass mortality, since CO2 -induced stomatal closure reduces transpiration, thus, offsets increased transpiration from CO2 -induced higher foliage area.
Collapse
Affiliation(s)
- Yitong Yao
- Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA‐CNRS‐UVSQUniversité Paris‐SaclayGif‐sur‐YvetteFrance
| | - Philippe Ciais
- Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA‐CNRS‐UVSQUniversité Paris‐SaclayGif‐sur‐YvetteFrance
| | - Nicolas Viovy
- Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA‐CNRS‐UVSQUniversité Paris‐SaclayGif‐sur‐YvetteFrance
| | - Emilie Joetzjer
- INRAE, Universite de Lorraine, AgroParisTech, UMR SilvaNancyFrance
| | - Jerome Chave
- Laboratoire Evolution et Diversité Biologique UMR 5174 CNRS, IRDUniversité Paul SabatierToulouseFrance
| |
Collapse
|
17
|
Zhang YJ, Hochberg U, Rockwell FE, Ponomarenko A, Chen YJ, Manandhar A, Graham AC, Holbrook NM. Xylem conduit deformation across vascular plants: an evolutionary spandrel or protective valve? THE NEW PHYTOLOGIST 2023; 237:1242-1255. [PMID: 36307967 DOI: 10.1111/nph.18584] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Accepted: 10/18/2022] [Indexed: 06/16/2023]
Abstract
The hydraulic system of vascular plants and its integrity is essential for plant survival. To transport water under tension, the walls of xylem conduits must approximate rigid pipes. Against this expectation, conduit deformation has been reported in the leaves of a few species and hypothesized to function as a 'circuit breaker' against embolism. Experimental evidence is lacking, and its generality is unknown. We demonstrated the role of conduit deformation in protecting the upstream xylem from embolism through experiments on three species and surveyed a diverse selection of vascular plants for conduit deformation in leaves. Conduit deformation in minor veins occurred before embolism during slow dehydration. When leaves were exposed to transient increases in transpiration, conduit deformation was accompanied by large water potential differences from leaf to stem and minimal embolism in the upstream xylem. In the three species tested, collapsible vein endings provided clear protection of upstream xylem from embolism during transient increases in transpiration. We found conduit deformation in diverse vascular plants, including 11 eudicots, ginkgo, a cycad, a fern, a bamboo, and a grass species, but not in two bamboo and a palm species, demonstrating that the potential for 'circuit breaker' functionality may be widespread across vascular plants.
Collapse
Affiliation(s)
- Yong-Jiang Zhang
- School of Biology and Ecology, University of Maine, Orono, ME, 04469, USA
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
- Climate Change Institute, University of Maine, Orono, ME, 04469, USA
| | - Uri Hochberg
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
- ARO Volcani Center, Institute of Soil, Water and Environmental Sciences, Rishon Lezion, 7505101, Israel
| | - Fulton E Rockwell
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Alexandre Ponomarenko
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Ya-Jun Chen
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan, 666303, China
| | - Anju Manandhar
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Adam C Graham
- Center for Nanoscale Systems, Harvard University, Cambridge, MA, 02138, USA
| | - N Michele Holbrook
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
| |
Collapse
|
18
|
Docherty EM, Gloor E, Sponchiado D, Gilpin M, Pinto CAD, Junior HM, Coughlin I, Ferreira L, Junior JAS, da Costa ACL, Meir P, Galbraith D. Long-term drought effects on the thermal sensitivity of Amazon forest trees. PLANT, CELL & ENVIRONMENT 2023; 46:185-198. [PMID: 36230004 PMCID: PMC10092618 DOI: 10.1111/pce.14465] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 10/07/2022] [Accepted: 10/09/2022] [Indexed: 06/16/2023]
Abstract
The continued functioning of tropical forests under climate change depends on their resilience to drought and heat. However, there is little understanding of how tropical forests will respond to combinations of these stresses, and no field studies to date have explicitly evaluated whether sustained drought alters sensitivity to temperature. We measured the temperature response of net photosynthesis, foliar respiration and the maximum quantum efficiency of photosystem II (Fv /Fm ) of eight hyper-dominant Amazonian tree species at the world's longest-running tropical forest drought experiment, to investigate the effect of drought on forest thermal sensitivity. Despite a 0.6°C-2°C increase in canopy air temperatures following long-term drought, no change in overall thermal sensitivity of net photosynthesis or respiration was observed. However, photosystem II tolerance to extreme-heat damage (T50 ) was reduced from 50.0 ± 0.3°C to 48.5 ± 0.3°C under drought. Our results suggest that long-term reductions in precipitation, as projected across much of Amazonia by climate models, are unlikely to greatly alter the response of tropical forests to rising mean temperatures but may increase the risk of leaf thermal damage during heatwaves.
Collapse
Affiliation(s)
- Emma M. Docherty
- Department of Earth and Environment, School of GeographyUniversity of LeedsLeedsUK
| | - Emanuel Gloor
- Department of Earth and Environment, School of GeographyUniversity of LeedsLeedsUK
| | - Daniela Sponchiado
- Departamento de Ciências Biológicas, Laboratório de Ecologia VegetalUniversidade do Estado de Mato GrossoNova XavantinaMato GrossoBrasil
| | - Martin Gilpin
- Department of Earth and Environment, School of GeographyUniversity of LeedsLeedsUK
| | | | | | - Ingrid Coughlin
- Departamento de Biologia, FFCLRPUniversidade de São PauloRibeirao PretoSão PauloBrasil
- College of Science, Research School of BiologyAustralian National UniversityCanberraAustralian Capital TerritorAustralia
| | | | | | - Antonio C. L. da Costa
- Instituto de GeosciênciasUniversidade Federaldo ParáBelémParáBrasil
- Museu Paraense Emílio GoeldiBelémParáBrasil
| | - Patrick Meir
- College of Science, Research School of BiologyAustralian National UniversityCanberraAustralian Capital TerritorAustralia
- College of Science and Engineering, School of GeoSciencesUniversity of EdinburghEdinburghUK
| | - David Galbraith
- Department of Earth and Environment, School of GeographyUniversity of LeedsLeedsUK
| |
Collapse
|
19
|
Increasing and widespread vulnerability of intact tropical rainforests to repeated droughts. Proc Natl Acad Sci U S A 2022; 119:e2116626119. [PMID: 36067321 PMCID: PMC9477241 DOI: 10.1073/pnas.2116626119] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Intact tropical rainforests have been exposed to severe droughts in recent decades, which may threaten their integrity, their ability to sequester carbon, and their capacity to provide shelter for biodiversity. However, their response to droughts remains uncertain due to limited high-quality, long-term observations covering extensive areas. Here, we examined how the upper canopy of intact tropical rainforests has responded to drought events globally and during the past 3 decades. By developing a long pantropical time series (1992 to 2018) of monthly radar satellite observations, we show that repeated droughts caused a sustained decline in radar signal in 93%, 84%, and 88% of intact tropical rainforests in the Americas, Africa, and Asia, respectively. Sudden decreases in radar signal were detected around the 1997-1998, 2005, 2010, and 2015 droughts in tropical Americas; 1999-2000, 2004-2005, 2010-2011, and 2015 droughts in tropical Africa; and 1997-1998, 2006, and 2015 droughts in tropical Asia. Rainforests showed similar low resistance (the ability to maintain predrought condition when drought occurs) to severe droughts across continents, but American rainforests consistently showed the lowest resilience (the ability to return to predrought condition after the drought event). Moreover, while the resistance of intact tropical rainforests to drought is decreasing, albeit weakly in tropical Africa and Asia, forest resilience has not increased significantly. Our results therefore suggest the capacity of intact rainforests to withstand future droughts is limited. This has negative implications for climate change mitigation through forest-based climate solutions and the associated pledges made by countries under the Paris Agreement.
Collapse
|
20
|
Bittencourt PRDL, Bartholomew DC, Banin LF, Bin Suis MAF, Nilus R, Burslem DFRP, Rowland L. Divergence of hydraulic traits among tropical forest trees across topographic and vertical environment gradients in Borneo. THE NEW PHYTOLOGIST 2022; 235:2183-2198. [PMID: 35633119 PMCID: PMC9545514 DOI: 10.1111/nph.18280] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 05/23/2022] [Indexed: 06/13/2023]
Abstract
Fine-scale topographic-edaphic gradients are common in tropical forests and drive species spatial turnover and marked changes in forest structure and function. We evaluate how hydraulic traits of tropical tree species relate to vertical and horizontal spatial niche specialization along such a gradient. Along a topographic-edaphic gradient with uniform climate in Borneo, we measured six key hydraulic traits in 156 individuals of differing heights in 13 species of Dipterocarpaceae. We investigated how hydraulic traits relate to habitat, tree height and their interaction on this gradient. Embolism resistance increased in trees on sandy soils but did not vary with tree height. By contrast, water transport capacity increased on sandier soils and with increasing tree height. Habitat and height only interact for hydraulic efficiency, with slope for height changing from positive to negative from the clay-rich to the sandier soil. Habitat type influenced trait-trait relationships for all traits except wood density. Our data reveal that variation in the hydraulic traits of dipterocarps is driven by a combination of topographic-edaphic conditions, tree height and taxonomic identity. Our work indicates that hydraulic traits play a significant role in shaping forest structure across topographic-edaphic and vertical gradients and may contribute to niche specialization among dipterocarp species.
Collapse
Affiliation(s)
| | - David C. Bartholomew
- College of Life and Environmental SciencesUniversity of ExeterExeterEX4 4QEUK
- Department of Ecology and Environmental ScienceUmeå University90736UmeåSweden
| | | | | | - Reuben Nilus
- Sabah Forestry DepartmentForest Research CentrePO Box 1407Sandakan90715SabahMalaysia
| | | | - Lucy Rowland
- College of Life and Environmental SciencesUniversity of ExeterExeterEX4 4QEUK
| |
Collapse
|
21
|
Zhou XL, Ma JY, Liu ZD, Dai NF, Yang HQ, Yang L, Wang YH, Shen SK. Gene Co-expression Network and Regression Analysis Identify the Transcriptomic, Physiological, and Biochemical Indicators of the Response of Alpine Woody Plant Rhododendron rex to Drought Stress. FRONTIERS IN PLANT SCIENCE 2022; 13:896691. [PMID: 35693180 PMCID: PMC9174646 DOI: 10.3389/fpls.2022.896691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 05/05/2022] [Indexed: 06/15/2023]
Abstract
Increasing severity of drought stress due to global change and extreme weather has been affecting the biodiversity, function, and stability of forest ecosystems. However, despite being an important component in the alpine and subalpine vegetation in forest ecosystems, Rhododendron species have been paid rare attention in the study of molecular mechanism of tolerance or response to drought. Herein, we investigated the correlation of transcriptomic changes with the physiological and biochemical indicators of Rhododendron rex under drought stress by using the co-expression network approach and regression analysis. Compared with the control treatment, the number of significantly differentially expressed unigenes (DEGs) increased with the degree of drought stress. The DEGs were mainly enriched in the cell wall metabolic process, signaling pathways, sugar metabolism, and nitrogen metabolism. Coupled analysis of the transcriptome, physiological, and biochemical parameters indicated that the metabolic pathways were highly correlated with the physiological and biochemical indicators under drought stress, especially the chlorophyll fluorescence parameters, such as the actual photosynthetic efficiency of photosystem II, electron transport rate, photochemical quenching coefficient, and the maximum quantum efficiency of photosystem II photochemistry. The majority of the response genes related to the metabolic pathways, including photosynthesis, sugar metabolism, and phytohormone signal pathway, were highly expressed under drought stress. In addition, genes associated with cell wall, pectin, and galacturonan metabolism also played crucial roles in the response of R. rex to drought stress. The results provided novel insight into the molecular response of the alpine woody species under drought stress and may improve the understanding of the response of forest ecosystems to the global climate change.
Collapse
Affiliation(s)
- Xiong-Li Zhou
- School of Ecology and Environmental Science, Yunnan University, Kunming, China
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Yunnan University, Kunming, China
- Yunnan Key Laboratory for Plateau Mountain Ecology and Restoration of Degraded Environments, Yunnan University, Kunming, China
| | - Jin-Yan Ma
- School of Ecology and Environmental Science, Yunnan University, Kunming, China
| | - Zhen-Dian Liu
- School of Ecology and Environmental Science, Yunnan University, Kunming, China
| | - Ni-fei Dai
- School of Ecology and Environmental Science, Yunnan University, Kunming, China
| | - Hui-Qin Yang
- School of Ecology and Environmental Science, Yunnan University, Kunming, China
| | - Liu Yang
- School of Ecology and Environmental Science, Yunnan University, Kunming, China
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Yunnan University, Kunming, China
| | - Yue-Hua Wang
- School of Ecology and Environmental Science, Yunnan University, Kunming, China
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Yunnan University, Kunming, China
| | - Shi-Kang Shen
- School of Ecology and Environmental Science, Yunnan University, Kunming, China
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Yunnan University, Kunming, China
- Yunnan Key Laboratory for Plateau Mountain Ecology and Restoration of Degraded Environments, Yunnan University, Kunming, China
| |
Collapse
|
22
|
Characteristics of Plant Community and Its Relationship with Groundwater Depth of the Desert Riparian Zone in the Lower Reaches of the Ugan River, Northwest China. WATER 2022. [DOI: 10.3390/w14101663] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
The vegetation in the desert riparian zone represents a critical barrier in the maintenance of the ecosystem’s balance. However, in recent years, the vegetation degradation of the riparian zone has seriously hindered economic development and ecological environment conservation. Based on a field investigation and literature, the mechanisms of vegetation degradation in the lower reaches of the Ugan River are discussed in this study through the analysis of plant coverage, diversity, substitution rate, distribution pattern, grey correlation analysis, and the relationship with groundwater depth. The results showed that the vegetation coverage in this region is relatively low when the water depth exceeds 4 m. Furthermore, the Shannon–Wiener index, the Simpson index, and the Pielou index all decreased with increases in water depth. Woody plants are the main species maintaining the ecological balance of the region with an aggregation distribution pattern. The degradation of vegetation is the result of the lack of water sources and the intense water consumption caused by human activities (especially agricultural). To promote ecological balance and vegetation restoration, the relative optimal water depth range should be maintained within 2 to 5 m as well as proper control of human activities. In addition, the degraded vegetation can gradually be restored using point and surface (i.e., flowering in the center and spreading to the surrounding areas). The results can provide a scientific basis for vegetation restoration and ecological conservation in the lower reaches of China’s Ugan River.
Collapse
|
23
|
Variations in leaf water status and drought tolerance of dominant tree species growing in multi-aged tropical forests in Thailand. Sci Rep 2022; 12:6882. [PMID: 35477746 PMCID: PMC9044374 DOI: 10.1038/s41598-022-10988-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 04/18/2022] [Indexed: 11/13/2022] Open
Abstract
Large-scale abandoned agricultural areas in Southeast Asia resulted in patches of forests of multiple successions and characteristics, challenging the study of their responses to environmental changes, especially under climatic water stress. Here, we investigated seasonal variation in leaf water status and drought tolerance of dominant tree species in three multi-aged tropical forests, ranging from 5 to > 200 years old, with contrasting soil moisture in Thailand. Seasonal variation in leaf water status differed among the forests with trees in young and intermediate sites demonstrating larger differences between seasons than the old-growth forest. Although vulnerability to embolism curves revealed that trees in old-growth forest were potentially more sensitive to declining leaf water status than others, they were predicted to lose < 5% of their hydraulic capacity as opposed to 13% for the trees in the younger sites. Our results suggest that the responses to water stress of tree species in different forest ages greatly vary with a tendency of trees in younger sites to be more resilience than those in older sites. Such information would benefit the selection of tree species that could adapt well to specific environments, thus improving the strategies for managing forests of different ages under a warmer future.
Collapse
|
24
|
Guillemot J, Martin-StPaul NK, Bulascoschi L, Poorter L, Morin X, Pinho BX, le Maire G, R L Bittencourt P, Oliveira RS, Bongers F, Brouwer R, Pereira L, Gonzalez Melo GA, Boonman CCF, Brown KA, Cerabolini BEL, Niinemets Ü, Onoda Y, Schneider JV, Sheremetiev S, Brancalion PHS. Small and slow is safe: On the drought tolerance of tropical tree species. GLOBAL CHANGE BIOLOGY 2022; 28:2622-2638. [PMID: 35007364 DOI: 10.1111/gcb.16082] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 12/09/2021] [Accepted: 12/09/2021] [Indexed: 06/14/2023]
Abstract
Understanding how evolutionary history and the coordination between trait trade-off axes shape the drought tolerance of trees is crucial to predict forest dynamics under climate change. Here, we compiled traits related to drought tolerance and the fast-slow and stature-recruitment trade-off axes in 601 tropical woody species to explore their covariations and phylogenetic signals. We found that xylem resistance to embolism (P50) determines the risk of hydraulic failure, while the functional significance of leaf turgor loss point (TLP) relies on its coordination with water use strategies. P50 and TLP exhibit weak phylogenetic signals and substantial variation within genera. TLP is closely associated with the fast-slow trait axis: slow species maintain leaf functioning under higher water stress. P50 is associated with both the fast-slow and stature-recruitment trait axes: slow and small species exhibit more resistant xylem. Lower leaf phosphorus concentration is associated with more resistant xylem, which suggests a (nutrient and drought) stress-tolerance syndrome in the tropics. Overall, our results imply that (1) drought tolerance is under strong selective pressure in tropical forests, and TLP and P50 result from the repeated evolutionary adaptation of closely related taxa, and (2) drought tolerance is coordinated with the ecological strategies governing tropical forest demography. These findings provide a physiological basis to interpret the drought-induced shift toward slow-growing, smaller, denser-wooded trees observed in the tropics, with implications for forest restoration programmes.
Collapse
Affiliation(s)
- Joannès Guillemot
- CIRAD, UMR Eco&Sols, Piracicaba, São Paulo, Brazil
- Eco&Sols, Univ. Montpellier, CIRAD, INRAe, Institut Agro, IRD, Montpellier, France
- Department of Forest Sciences, ESALQ, University of São Paulo, Piracicaba, São Paulo, Brazil
| | | | - Leticia Bulascoschi
- Department of Forest Sciences, ESALQ, University of São Paulo, Piracicaba, São Paulo, Brazil
| | - Lourens Poorter
- Forest Ecology and Forest Management Group, Wageningen University, Wageningen, The Netherlands
| | - Xavier Morin
- CEFE, CNRS, Univ. Montpellier, EPHE, IRD, Univ. Paul Valéry Montpellier 3, Montpellier, France
| | - Bruno X Pinho
- AMAP, Univ Montpellier, INRAe, CIRAD, CNRS, IRD, Montpellier, France
- Departamento de Botânica, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil
| | - Guerric le Maire
- CIRAD, UMR Eco&Sols, Piracicaba, São Paulo, Brazil
- Eco&Sols, Univ. Montpellier, CIRAD, INRAe, Institut Agro, IRD, Montpellier, France
| | | | - Rafael S Oliveira
- Department of Plant Biology, Institute of Biology, University of Campinas - UNICAMP, Campinas, São Paulo, Brazil
| | - Frans Bongers
- Forest Ecology and Forest Management Group, Wageningen University, Wageningen, The Netherlands
| | - Rens Brouwer
- Forest Ecology and Forest Management Group, Wageningen University, Wageningen, The Netherlands
| | - Luciano Pereira
- Department of Plant Biology, Institute of Biology, University of Campinas - UNICAMP, Campinas, São Paulo, Brazil
- Institute of Systematic Botany and Ecology, Ulm University, Ulm, Germany
| | | | - Coline C F Boonman
- Department of Aquatic Ecology and Environmental Biology, Institute for Water and Wetland Research, Radboud University, Nijmegen, The Netherlands
| | - Kerry A Brown
- Department of Geography, Geology and the Environment, Kingston University London, Kingston Upon Thames, UK
| | - Bruno E L Cerabolini
- Department of Biotechnologies and Life Sciences (DBSV), University of Insubria, Varese, Italy
| | - Ülo Niinemets
- Estonian University of Life Sciences, Tartu, Estonia
| | - Yusuke Onoda
- Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Julio V Schneider
- Department of Botany and Molecular Evolution, Senckenberg Research Institute and Natural History Museum Frankfurt, Frankfurt, Germany
- Senckenberg Research Institute and Natural History Museum Frankfurt, Frankfurt, Germany
| | | | - Pedro H S Brancalion
- Department of Forest Sciences, ESALQ, University of São Paulo, Piracicaba, São Paulo, Brazil
| |
Collapse
|
25
|
Giles AL, Rowland L, Bittencourt PRL, Bartholomew DC, Coughlin I, Costa PB, Domingues T, Miatto RC, Barros FV, Ferreira LV, Groenendijk P, Oliveira AAR, da Costa ACL, Meir P, Mencuccini M, Oliveira RS. Small understorey trees have greater capacity than canopy trees to adjust hydraulic traits following prolonged experimental drought in a tropical forest. TREE PHYSIOLOGY 2022; 42:537-556. [PMID: 34508606 DOI: 10.1093/treephys/tpab121] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 09/08/2021] [Indexed: 06/13/2023]
Abstract
Future climate change predictions for tropical forests highlight increased frequency and intensity of extreme drought events. However, it remains unclear whether large and small trees have differential strategies to tolerate drought due to the different niches they occupy. The future of tropical forests is ultimately dependent on the capacity of small trees (<10 cm in diameter) to adjust their hydraulic system to tolerate drought. To address this question, we evaluated whether the drought tolerance of neotropical small trees can adjust to experimental water stress and was different from tall trees. We measured multiple drought resistance-related hydraulic traits across nine common neotropical genera at the world's longest-running tropical forest throughfall-exclusion experiment and compared their responses with surviving large canopy trees. Small understorey trees in both the control and the throughfall-exclusion treatment had lower minimum stomatal conductance and maximum hydraulic leaf-specific conductivity relative to large trees of the same genera, as well as a greater hydraulic safety margin (HSM), percentage loss of conductivity and embolism resistance, demonstrating that they occupy a distinct hydraulic niche. Surprisingly, in response to the drought treatment, small trees increased specific hydraulic conductivity by 56.3% and leaf:sapwood area ratio by 45.6%. The greater HSM of small understorey trees relative to large canopy trees likely enabled them to adjust other aspects of their hydraulic systems to increase hydraulic conductivity and take advantage of increases in light availability in the understorey resulting from the drought-induced mortality of canopy trees. Our results demonstrate that differences in hydraulic strategies between small understorey and large canopy trees drive hydraulic niche segregation. Small understorey trees can adjust their hydraulic systems in response to changes in water and light availability, indicating that natural regeneration of tropical forests following long-term drought may be possible.
Collapse
Affiliation(s)
- A L Giles
- Instituto de Biologia, University of Campinas (UNICAMP), R. Monteiro Lobato, 255 - Barão Geraldo, Campinas SP 13083-970, Brazil
| | - L Rowland
- College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4RJ, UK
| | - P R L Bittencourt
- College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4RJ, UK
| | - D C Bartholomew
- College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4RJ, UK
| | - I Coughlin
- Departamento de Biologia, FFCLRP, Universidade de São Paulo, Av. Bandeirantes, 3900 - Vila Monte Alegre, Ribeirão Preto SP 14040-900, Brazil
- Research School of Biology, Australian National University, 134 Linnaeus Way, Canberra ACT 2601, Australia
| | - P B Costa
- Instituto de Biologia, University of Campinas (UNICAMP), R. Monteiro Lobato, 255 - Barão Geraldo, Campinas SP 13083-970, Brazil
- Biological Sciences, Stirling Highway, Perth, WA 6009, Australia
| | - T Domingues
- Departamento de Biologia, FFCLRP, Universidade de São Paulo, Av. Bandeirantes, 3900 - Vila Monte Alegre, Ribeirão Preto SP 14040-900, Brazil
| | - R C Miatto
- Departamento de Biologia, FFCLRP, Universidade de São Paulo, Av. Bandeirantes, 3900 - Vila Monte Alegre, Ribeirão Preto SP 14040-900, Brazil
| | - F V Barros
- College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4RJ, UK
| | - L V Ferreira
- Museu Paraense Emílio Goeldi, Av. Gov Magalhães Barata, 376 - São Brás, Belém PA 66040-170, Brazil
| | - P Groenendijk
- Instituto de Biologia, University of Campinas (UNICAMP), R. Monteiro Lobato, 255 - Barão Geraldo, Campinas SP 13083-970, Brazil
| | - A A R Oliveira
- Museu Paraense Emílio Goeldi, Av. Gov Magalhães Barata, 376 - São Brás, Belém PA 66040-170, Brazil
| | - A C L da Costa
- Museu Paraense Emílio Goeldi, Av. Gov Magalhães Barata, 376 - São Brás, Belém PA 66040-170, Brazil
- Biological Sciences, Stirling Highway, Perth, WA 6009, Australia
| | - P Meir
- Research School of Biology, Australian National University, 134 Linnaeus Way, Canberra ACT 2601, Australia
- School of GeoSciences, University of Edinburgh, Drummond St Edinburgh EH9 3FF, UK
| | - M Mencuccini
- CREAF, Campus UAB, Edifici C Campus de Bellaterra Cerdanyola del Vallés 08193, Spain
- ICREA, Passeig de Lluís Companys, 23, Barcelona 08010, Spain
| | - R S Oliveira
- Instituto de Biologia, University of Campinas (UNICAMP), R. Monteiro Lobato, 255 - Barão Geraldo, Campinas SP 13083-970, Brazil
| |
Collapse
|
26
|
Weithmann G, Link RM, Banzragch BE, Würzberg L, Leuschner C, Schuldt B. Soil water availability and branch age explain variability in xylem safety of European beech in Central Europe. Oecologia 2022; 198:629-644. [PMID: 35212818 PMCID: PMC8956530 DOI: 10.1007/s00442-022-05124-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 01/24/2022] [Indexed: 12/17/2022]
Abstract
Xylem embolism resistance has been identified as a key trait with a causal relation to drought-induced tree mortality, but not much is known about its intra-specific trait variability (ITV) in dependence on environmental variation. We measured xylem safety and efficiency in 300 European beech (Fagus sylvatica L.) trees across 30 sites in Central Europe, covering a precipitation reduction from 886 to 522 mm year−1. A broad range of variables that might affect embolism resistance in mature trees, including climatic and soil water availability, competition, and branch age, were examined. The average P50 value varied by up to 1 MPa between sites. Neither climatic aridity nor structural variables had a significant influence on P50. However, P50 was less negative for trees with a higher soil water storage capacity, and positively related to branch age, while specific conductivity (Ks) was not significantly associated with either of these variables. The greatest part of the ITV for xylem safety and efficiency was attributed to random variability within populations. We conclude that the influence of site water availability on P50 and Ks is low in European beech, and that the high degree of within-population variability for P50, partly due to variation in branch age, hampers the identification of a clear environmental signal.
Collapse
Affiliation(s)
- Greta Weithmann
- Plant Ecology, Albrecht Von Haller Institute for Plant Sciences, University of Goettingen, Untere Karspüle 2, 37073, Göttingen, Germany
| | - Roman M Link
- Plant Ecology, Albrecht Von Haller Institute for Plant Sciences, University of Goettingen, Untere Karspüle 2, 37073, Göttingen, Germany.,Ecophysiology and Vegetation Ecology, Julius-von-Sachs-Institute of Biological Sciences, University of Würzburg, Julius-von-Sachs-Platz, 97082, Würzburg, Germany
| | - Bat-Enerel Banzragch
- Plant Ecology, Albrecht Von Haller Institute for Plant Sciences, University of Goettingen, Untere Karspüle 2, 37073, Göttingen, Germany
| | - Laura Würzberg
- Plant Ecology, Albrecht Von Haller Institute for Plant Sciences, University of Goettingen, Untere Karspüle 2, 37073, Göttingen, Germany
| | - Christoph Leuschner
- Plant Ecology, Albrecht Von Haller Institute for Plant Sciences, University of Goettingen, Untere Karspüle 2, 37073, Göttingen, Germany.,Centre for Biodiversity and Sustainable Land Use (CBL), University of Goettingen, 37075, Göttingen, Germany
| | - Bernhard Schuldt
- Plant Ecology, Albrecht Von Haller Institute for Plant Sciences, University of Goettingen, Untere Karspüle 2, 37073, Göttingen, Germany. .,Ecophysiology and Vegetation Ecology, Julius-von-Sachs-Institute of Biological Sciences, University of Würzburg, Julius-von-Sachs-Platz, 97082, Würzburg, Germany.
| |
Collapse
|
27
|
Garcia MN, Hu J, Domingues TF, Groenendijk P, Oliveira RS, Costa FRC. Local hydrological gradients structure high intraspecific variability in plant hydraulic traits in two dominant central Amazonian tree species. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:939-952. [PMID: 34545938 DOI: 10.1093/jxb/erab432] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 09/19/2021] [Indexed: 06/13/2023]
Abstract
Addressing the intraspecific variability of functional traits helps understand how climate change might influence the distribution of organismal traits across environments, but this is notably understudied in the Amazon, especially for plant hydraulic traits commonly used to project drought responses. We quantified the intraspecific trait variability of leaf mass per area, wood density, and xylem embolism resistance for two dominant central Amazonian tree species, along gradients of water and light availability, while accounting for tree age and height. Intraspecific variability in hydraulic traits was high, with within-species variability comparable to the whole-community variation. Hydraulic trait variation was modulated mostly by the hydrological environment, with higher embolism resistance of trees growing on deep-water-table plateaus compared with shallow-water-table valleys. Intraspecific variability of leaf mass per area and wood density was mostly modulated by intrinsic factors and light. The different environmental and intrinsic drivers of variation among and within individuals lead to an uncoupled coordination among carbon acquisition/conservation and water-use traits. Our findings suggest multivariate ecological strategies driving tropical tree distributions even within species, and reflect differential within-population sensitivities along environmental gradients. Therefore, intraspecific trait variability must be considered for accurate predictions of the responses of tropical forests to climate change.
Collapse
Affiliation(s)
- Maquelle N Garcia
- Tropical Forest Science Program, National Institute of Amazon Researches, Manaus, AM, Brazil
| | - Jia Hu
- School of Natural Resources and the Environment, University of Arizona, Tucson, AZ, USA
| | - Tomas F Domingues
- Department of Biology, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Peter Groenendijk
- Department of Plant Biology, Institute of Biology, P.O. Box: 6109, University of Campinas - UNICAMP, 13083-970, Campinas, SP, Brazil
| | - Rafael S Oliveira
- Department of Plant Biology, Institute of Biology, P.O. Box: 6109, University of Campinas - UNICAMP, 13083-970, Campinas, SP, Brazil
| | - Flávia R C Costa
- Coordenação de Pesquisas em Biodiversidade, Instituto Nacional de Pesquisas da Amazônia, Caixa Postal 2223, CEP 69008-971, Manaus, AM, Brazil
| |
Collapse
|
28
|
Nardini A. Can trees harden up to survive global change-type droughts? TREE PHYSIOLOGY 2021; 41:2004-2007. [PMID: 34542153 DOI: 10.1093/treephys/tpab128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 09/16/2021] [Indexed: 06/13/2023]
Affiliation(s)
- Andrea Nardini
- Dipartimento di Scienze della Vita, Università di Trieste, Via L. Giorgieri 10, 34127 Trieste, Italy
| |
Collapse
|
29
|
Trabi CL, Pereira L, Guan X, Miranda MT, Bittencourt PRL, Oliveira RS, Ribeiro RV, Jansen S. A User Manual to Measure Gas Diffusion Kinetics in Plants: Pneumatron Construction, Operation, and Data Analysis. FRONTIERS IN PLANT SCIENCE 2021; 12:633595. [PMID: 34163496 PMCID: PMC8216216 DOI: 10.3389/fpls.2021.633595] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 05/12/2021] [Indexed: 05/17/2023]
Abstract
The Pneumatron device measures gas diffusion kinetics in the xylem of plants. The device provides an easy, low-cost, and powerful tool for research on plant water relations and gas exchange. Here, we describe in detail how to construct and operate this device to estimate embolism resistance of angiosperm xylem, and how to analyse pneumatic data. Simple and more elaborated ways of constructing a Pneumatron are shown, either using wires, a breadboard, or a printed circuit board. The instrument is based on an open-source hardware and software system, which allows users to operate it in an automated or semi-automated way. A step-by-step manual and a troubleshooting section are provided. An excel spreadsheet and an R-script are also presented for fast and easy data analysis. This manual aims at helping users to avoid common mistakes, such as unstable measurements of the minimum and maximum amount of gas discharged from xylem tissue, which has major consequences for estimating embolism resistance. Major advantages of the Pneumatron device include its automated and accurate measurements of gas diffusion rates, including highly precise measurements of the gas volume in intact, embolised conduits. It is currently unclear if the method can also be applied to woody monocots, gymnosperm species that possess torus-margo pit membranes, or to herbaceous species.
Collapse
Affiliation(s)
| | - Luciano Pereira
- Institute of Systematic Botany and Ecology, Ulm University, Ulm, Germany
- Center R&D in Ecophysiology and Biophysics, Agronomic Institute (IAC), Campinas, Brazil
- Department of Plant Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Xinyi Guan
- Institute of Systematic Botany and Ecology, Ulm University, Ulm, Germany
| | - Marcela T. Miranda
- Center R&D in Ecophysiology and Biophysics, Agronomic Institute (IAC), Campinas, Brazil
| | | | - Rafael S. Oliveira
- Department of Plant Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Rafael V. Ribeiro
- Department of Plant Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Steven Jansen
- Institute of Systematic Botany and Ecology, Ulm University, Ulm, Germany
| |
Collapse
|
30
|
Rowland L, Martínez-Vilalta J, Mencuccini M. Hard times for high expectations from hydraulics: predicting drought-induced forest mortality at landscape scales remains a challenge. THE NEW PHYTOLOGIST 2021; 230:1685-1687. [PMID: 33797779 DOI: 10.1111/nph.17317] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Affiliation(s)
- Lucy Rowland
- College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4QE, UK
| | - Jordi Martínez-Vilalta
- CREAF, Bellaterra (Cerdanyola del Vallès), 08193, Spain
- Universitat Autònoma de Barcelona, Bellaterra (Cerdanyola del Vallès), 08193, Spain
| | - Maurizio Mencuccini
- CREAF, Bellaterra (Cerdanyola del Vallès), 08193, Spain
- ICREA, Pg. Lluís Companys 23, Barcelona, 08010, Spain
| |
Collapse
|
31
|
Nunes MH, Jucker T, Riutta T, Svátek M, Kvasnica J, Rejžek M, Matula R, Majalap N, Ewers RM, Swinfield T, Valbuena R, Vaughn NR, Asner GP, Coomes DA. Recovery of logged forest fragments in a human-modified tropical landscape during the 2015-16 El Niño. Nat Commun 2021; 12:1526. [PMID: 33750781 PMCID: PMC7943823 DOI: 10.1038/s41467-020-20811-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Accepted: 12/02/2020] [Indexed: 01/29/2023] Open
Abstract
The past 40 years in Southeast Asia have seen about 50% of lowland rainforests converted to oil palm and other plantations, and much of the remaining forest heavily logged. Little is known about how fragmentation influences recovery and whether climate change will hamper restoration. Here, we use repeat airborne LiDAR surveys spanning the hot and dry 2015-16 El Niño Southern Oscillation event to measure canopy height growth across 3,300 ha of regenerating tropical forests spanning a logging intensity gradient in Malaysian Borneo. We show that the drought led to increased leaf shedding and branch fall. Short forest, regenerating after heavy logging, continued to grow despite higher evaporative demand, except when it was located close to oil palm plantations. Edge effects from the plantations extended over 300 metres into the forests. Forest growth on hilltops and slopes was particularly impacted by the combination of fragmentation and drought, but even riparian forests located within 40 m of oil palm plantations lost canopy height during the drought. Our results suggest that small patches of logged forest within plantation landscapes will be slow to recover, particularly as ENSO events are becoming more frequent. It is unclear whether tropical forest fragments within plantation landscapes are resilient to drought. Here the authors analyse LiDAR and ground-based data from the 2015-16 El Niño event across a logging intensity gradient in Borneo. Although regenerating forests continued to grow, canopy height near oil palm plantations decreased, and a strong edge effect extended up to at least 300 m away.
Collapse
Affiliation(s)
- Matheus Henrique Nunes
- Department of Plant Sciences and Conservation Research Institute, University of Cambridge, Cambridge, CB2 3QZ, UK. .,Department of Geosciences and Geography, University of Helsinki, Helsinki, 00014, Finland.
| | - Tommaso Jucker
- Department of Plant Sciences and Conservation Research Institute, University of Cambridge, Cambridge, CB2 3QZ, UK.,School of Biological Sciences, University of Bristol, Bristol, BS8 1TH, UK
| | - Terhi Riutta
- Department of Life Sciences, Imperial College London, Silwood Park Campus, Buckhurst Road, Ascot, Berkshire, SL5 7PY, UK.,School of Geography and the Environment, Environmental Change Institute, University of Oxford, Oxford, OX1 3QY, UK
| | - Martin Svátek
- Department of Forest Botany, Dendrology and Geobiocoenology, Faculty of Forestry and Wood Technology, Mendel University in Brno, 613 00, Brno, Czech Republic
| | - Jakub Kvasnica
- Department of Forest Botany, Dendrology and Geobiocoenology, Faculty of Forestry and Wood Technology, Mendel University in Brno, 613 00, Brno, Czech Republic
| | - Martin Rejžek
- Department of Forest Botany, Dendrology and Geobiocoenology, Faculty of Forestry and Wood Technology, Mendel University in Brno, 613 00, Brno, Czech Republic
| | - Radim Matula
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Kamýcká 129, Prague, 165 00, Czech Republic
| | | | - Robert M Ewers
- Department of Life Sciences, Imperial College London, Silwood Park Campus, Buckhurst Road, Ascot, Berkshire, SL5 7PY, UK
| | - Tom Swinfield
- Department of Plant Sciences and Conservation Research Institute, University of Cambridge, Cambridge, CB2 3QZ, UK
| | - Rubén Valbuena
- Department of Plant Sciences and Conservation Research Institute, University of Cambridge, Cambridge, CB2 3QZ, UK.,School of Natural Sciences, Bangor University, Gwynedd, LL57 2UW, UK
| | - Nicholas R Vaughn
- Center for Global Discovery and Conservation Science, Arizona State University, Tempe AZ and Hilo, Tempe, HI, USA
| | - Gregory P Asner
- Center for Global Discovery and Conservation Science, Arizona State University, Tempe AZ and Hilo, Tempe, HI, USA
| | - David A Coomes
- Department of Plant Sciences and Conservation Research Institute, University of Cambridge, Cambridge, CB2 3QZ, UK.
| |
Collapse
|
32
|
Rowland L, Oliveira RS, Bittencourt PRL, Giles AL, Coughlin I, Costa PDB, Domingues T, Ferreira LV, Vasconcelos SS, Junior JAS, Oliveira AAR, da Costa ACL, Meir P, Mencuccini M. Plant traits controlling growth change in response to a drier climate. THE NEW PHYTOLOGIST 2021; 229:1363-1374. [PMID: 32981040 DOI: 10.1111/nph.16972] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 09/16/2020] [Indexed: 06/11/2023]
Abstract
Plant traits are increasingly being used to improve prediction of plant function, including plant demography. However, the capability of plant traits to predict demographic rates remains uncertain, particularly in the context of trees experiencing a changing climate. Here we present data combining 17 plant traits associated with plant structure, metabolism and hydraulic status, with measurements of long-term mean, maximum and relative growth rates for 176 trees from the world's longest running tropical forest drought experiment. We demonstrate that plant traits can predict mean annual tree growth rates with moderate explanatory power. However, only combinations of traits associated more directly with plant functional processes, rather than more commonly employed traits like wood density or leaf mass per area, yield the power to predict growth. Critically, we observe a shift from growth being controlled by traits related to carbon cycling (assimilation and respiration) in well-watered trees, to traits relating to plant hydraulic stress in drought-stressed trees. We also demonstrate that even with a very comprehensive set of plant traits and growth data on large numbers of tropical trees, considerable uncertainty remains in directly interpreting the mechanisms through which traits influence performance in tropical forests.
Collapse
Affiliation(s)
- Lucy Rowland
- College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4RJ, UK
| | - Rafael S Oliveira
- Instituto de Biologia, University of Campinas (UNICAMP), Campinas, SP, 13083-970, Brasil
- Biological Sciences, UWA, Perth, Crawle, WA, 6009, Australia
| | - Paulo R L Bittencourt
- College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4RJ, UK
- Programa de Pós Graduação em Ecologia Institute of Biology, University of Campinas - UNICAMP 13083-970, PO Box 6109, Campinas, SP, Brazil
| | - Andre L Giles
- Programa de Pós Graduação em Ecologia Institute of Biology, University of Campinas - UNICAMP 13083-970, PO Box 6109, Campinas, SP, Brazil
| | - Ingrid Coughlin
- Departamento de Biologia, FFCLRP, Universidade de São Paulo, Ribeirão Preto, SP, 14040-900, Brasil
- Research School of Biology, Australian National University, Canberra, ACT, 2601, Australia
| | - Patricia de Britto Costa
- Biological Sciences, UWA, Perth, Crawle, WA, 6009, Australia
- Programa de Pós Graduação em Biologia Vegetal Institute of Biology, University of Campinas - UNICAMP, PO Box 6109, Campinas, SP, 13083-970, Brazil
| | - Tomas Domingues
- Departamento de Biologia, FFCLRP, Universidade de São Paulo, Ribeirão Preto, SP, 14040-900, Brasil
| | | | | | - João A S Junior
- Instituto de Geosciências, Universidade Federal do Pará, Belém, PA, 66075-110, Brasil
| | - Alex A R Oliveira
- School of GeoSciences, University of Edinburgh, Edinburgh, EH9 3FF, UK
| | - Antonio C L da Costa
- Museu Paraense Emílio Goeldi, Belém, PA, 66040-170, Brasil
- EMBRAPA Amazônia Oriental, 14 Belém, PA, 66095-903, Brasil
| | - Patrick Meir
- Research School of Biology, Australian National University, Canberra, ACT, 2601, Australia
- School of GeoSciences, University of Edinburgh, Edinburgh, EH9 3FF, UK
| | - Maurizio Mencuccini
- CREAF, Campus UAB, Cerdanyola del Vallés, 08193, Spain
- ICREA, Barcelona, 08010, Spain
| |
Collapse
|
33
|
Levionnois S, Jansen S, Wandji RT, Beauchêne J, Ziegler C, Coste S, Stahl C, Delzon S, Authier L, Heuret P. Linking drought-induced xylem embolism resistance to wood anatomical traits in Neotropical trees. THE NEW PHYTOLOGIST 2021; 229:1453-1466. [PMID: 32964439 DOI: 10.1111/nph.16942] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 09/04/2020] [Indexed: 05/27/2023]
Abstract
Drought-induced xylem embolism is considered to be one of the main factors driving mortality in woody plants worldwide. Although several structure-functional mechanisms have been tested to understand the anatomical determinants of embolism resistance, there is a need to study this topic by integrating anatomical data for many species. We combined optical, laser, and transmission electron microscopy to investigate vessel diameter, vessel grouping, and pit membrane ultrastructure for 26 tropical rainforest tree species across three major clades (magnoliids, rosiids, and asteriids). We then related these anatomical observations to previously published data on drought-induced embolism resistance, with phylogenetic analyses. Vessel diameter, vessel grouping, and pit membrane ultrastructure were all predictive of xylem embolism resistance, but with weak predictive power. While pit membrane thickness was a predictive trait when vestured pits were taken into account, the pit membrane diameter-to-thickness ratio suggests a strong importance of the deflection resistance of the pit membrane. However, phylogenetic analyses weakly support adaptive coevolution. Our results emphasize the functional significance of pit membranes for air-seeding in tropical rainforest trees, highlighting also the need to study their mechanical properties due to the link between embolism resistance and pit membrane diameter-to-thickness ratio. Finding support for adaptive coevolution also remains challenging.
Collapse
Affiliation(s)
- Sébastien Levionnois
- UMR EcoFoG, AgroParisTech, CIRAD, CNRS, INRAE, Université des Antilles, Université de Guyane, Kourou, 97310, France
- UMR AMAP, Université de Montpellier, CIRAD, CNRS, INRAE, IRD, Montpellier, 34000, France
| | - Steven Jansen
- Institute of Systematic Botany and Ecology, Ulm University, Ulm, D-89081, Germany
| | - Ruth Tchana Wandji
- UMR EcoFoG, AgroParisTech, CIRAD, CNRS, INRAE, Université des Antilles, Université de Guyane, Kourou, 97310, France
| | - Jacques Beauchêne
- UMR EcoFoG, AgroParisTech, CIRAD, CNRS, INRAE, Université des Antilles, Université de Guyane, Kourou, 97310, France
| | - Camille Ziegler
- UMR EcoFoG, AgroParisTech, CIRAD, CNRS, INRAE, Université des Antilles, Université de Guyane, Kourou, 97310, France
- AgroParisTech, UMR Silva, INRAE, Université de Lorraine, Nancy, F-54000, France
| | - Sabrina Coste
- UMR EcoFoG, AgroParisTech, CIRAD, CNRS, INRAE, Université des Antilles, Université de Guyane, Kourou, 97310, France
| | - Clément Stahl
- UMR EcoFoG, AgroParisTech, CIRAD, CNRS, INRAE, Université des Antilles, Université de Guyane, Kourou, 97310, France
| | - Sylvain Delzon
- UMR BIOGECO, INRAE, Université de Bordeaux, Pessac, 33615, France
| | - Louise Authier
- UMR EcoFoG, AgroParisTech, CIRAD, CNRS, INRAE, Université des Antilles, Université de Guyane, Kourou, 97310, France
| | - Patrick Heuret
- UMR EcoFoG, AgroParisTech, CIRAD, CNRS, INRAE, Université des Antilles, Université de Guyane, Kourou, 97310, France
| |
Collapse
|
34
|
Doughty CE, Cheesman AW, Riutta T, Thomson ER, Shenkin A, Nottingham AT, Telford EM, Huaraca Huasco W, Majalap N, Arn Teh Y, Meir P, Malhi Y. Predicting tropical tree mortality with leaf spectroscopy. Biotropica 2020. [DOI: 10.1111/btp.12901] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Christopher E. Doughty
- School of Informatics, Computing, and Cyber Systems Northern Arizona University Flagstaff AZ USA
| | - Alexander W. Cheesman
- College of Life and Environmental Sciences University of Exeter Exeter UK
- College of Science & Engineering James Cook University Cairns Qld Australia
| | - Terhi Riutta
- Environmental Change Institute School of Geography and the Environment University of Oxford Oxford UK
- Department of Life Sciences Imperial College London Ascot UK
| | - Eleanor R. Thomson
- Environmental Change Institute School of Geography and the Environment University of Oxford Oxford UK
| | - Alexander Shenkin
- Environmental Change Institute School of Geography and the Environment University of Oxford Oxford UK
| | - Andrew T. Nottingham
- School of Geography, University of Leeds Leeds UK
- School of Geosciences University of Edinburgh Edinburgh UK
| | | | - Walter Huaraca Huasco
- Environmental Change Institute School of Geography and the Environment University of Oxford Oxford UK
| | - Noreen Majalap
- Forest Research Centre Sabah Forestry Department Sandakan Malaysia
| | - Yit Arn Teh
- School of Natural and Environmental Sciences Newcastle University Newcastle Upon Tyne UK
| | - Patrick Meir
- School of Geosciences University of Edinburgh Edinburgh UK
- Research School of Biology Australian National University Canberra ACT Australia
| | - Yadvinder Malhi
- Environmental Change Institute School of Geography and the Environment University of Oxford Oxford UK
| |
Collapse
|
35
|
Bartholomew DC, Bittencourt PRL, da Costa ACL, Banin LF, de Britto Costa P, Coughlin SI, Domingues TF, Ferreira LV, Giles A, Mencuccini M, Mercado L, Miatto RC, Oliveira A, Oliveira R, Meir P, Rowland L. Small tropical forest trees have a greater capacity to adjust carbon metabolism to long-term drought than large canopy trees. PLANT, CELL & ENVIRONMENT 2020; 43:2380-2393. [PMID: 32643169 DOI: 10.1111/pce.13838] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 06/30/2020] [Accepted: 07/01/2020] [Indexed: 06/11/2023]
Abstract
The response of small understory trees to long-term drought is vital in determining the future composition, carbon stocks and dynamics of tropical forests. Long-term drought is, however, also likely to expose understory trees to increased light availability driven by drought-induced mortality. Relatively little is known about the potential for understory trees to adjust their physiology to both decreasing water and increasing light availability. We analysed data on maximum photosynthetic capacity (Jmax , Vcmax ), leaf respiration (Rleaf ), leaf mass per area (LMA), leaf thickness and leaf nitrogen and phosphorus concentrations from 66 small trees across 12 common genera at the world's longest running tropical rainfall exclusion experiment and compared responses to those from 61 surviving canopy trees. Small trees increased Jmax , Vcmax , Rleaf and LMA (71, 29, 32, 15% respectively) in response to the drought treatment, but leaf thickness and leaf nutrient concentrations did not change. Small trees were significantly more responsive than large canopy trees to the drought treatment, suggesting greater phenotypic plasticity and resilience to prolonged drought, although differences among taxa were observed. Our results highlight that small tropical trees have greater capacity to respond to ecosystem level changes and have the potential to regenerate resilient forests following future droughts.
Collapse
Affiliation(s)
- David C Bartholomew
- School of Geography, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Paulo R L Bittencourt
- School of Geography, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
- Instituto de Biologia, University of Campinas (UNICAMP), Campinas, Brazil
| | | | | | | | - Sarah I Coughlin
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory, Australia
| | - Tomas F Domingues
- Departamento de Biologia, FFCLRP, Universidade de São Paulo, Ribeirão Preto, Brazil
| | | | - André Giles
- Instituto de Biologia, University of Campinas (UNICAMP), Campinas, Brazil
| | - Maurizio Mencuccini
- ICREA, Barcelona, Spain
- CREAF, Universidad Autonoma de Barcelona, Barcelona, Spain
| | - Lina Mercado
- School of Geography, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
- UK Centre for Ecology and Hydrology, Wallingford, UK
| | - Raquel C Miatto
- Departamento de Biologia, FFCLRP, Universidade de São Paulo, Ribeirão Preto, Brazil
| | | | - Rafael Oliveira
- Instituto de Biologia, University of Campinas (UNICAMP), Campinas, Brazil
| | - Patrick Meir
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory, Australia
- School of Geosciences, University of Edinburgh, Edinburgh, UK
| | - Lucy Rowland
- School of Geography, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| |
Collapse
|
36
|
De Kauwe MG, Medlyn BE, Ukkola AM, Mu M, Sabot MEB, Pitman AJ, Meir P, Cernusak LA, Rifai SW, Choat B, Tissue DT, Blackman CJ, Li X, Roderick M, Briggs PR. Identifying areas at risk of drought-induced tree mortality across South-Eastern Australia. GLOBAL CHANGE BIOLOGY 2020; 26:5716-5733. [PMID: 32512628 DOI: 10.1111/gcb.15215] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 05/25/2020] [Indexed: 06/11/2023]
Abstract
South-East Australia has recently been subjected to two of the worst droughts in the historical record (Millennium Drought, 2000-2009 and Big Dry, 2017-2019). Unfortunately, a lack of forest monitoring has made it difficult to determine whether widespread tree mortality has resulted from these droughts. Anecdotal observations suggest the Big Dry may have led to more significant tree mortality than the Millennium drought. Critically, to be able to robustly project future expected climate change effects on Australian vegetation, we need to assess the vulnerability of Australian trees to drought. Here we implemented a model of plant hydraulics into the Community Atmosphere Biosphere Land Exchange (CABLE) land surface model. We parameterized the drought response behaviour of five broad vegetation types, based on a common garden dry-down experiment with species originating across a rainfall gradient (188-1,125 mm/year) across South-East Australia. The new hydraulics model significantly improved (~35%-45% reduction in root mean square error) CABLE's previous predictions of latent heat fluxes during periods of water stress at two eddy covariance sites in Australia. Landscape-scale predictions of the greatest percentage loss of hydraulic conductivity (PLC) of about 40%-60%, were broadly consistent with satellite estimates of regions of the greatest change in both droughts. In neither drought did CABLE predict that trees would have reached critical PLC in widespread areas (i.e. it projected a low mortality risk), although the model highlighted critical levels near the desert regions of South-East Australia where few trees live. Overall, our experimentally constrained model results imply significant resilience to drought conferred by hydraulic function, but also highlight critical data and scientific gaps. Our approach presents a promising avenue to integrate experimental data and make regional-scale predictions of potential drought-induced hydraulic failure.
Collapse
Affiliation(s)
- Martin G De Kauwe
- ARC Centre of Excellence for Climate Extremes, Sydney, NSW, Australia
- Climate Change Research Centre, University of New South Wales, Sydney, NSW, Australia
- Evolution & Ecology Research Centre, University of New South Wales, Sydney, NSW, Australia
| | - Belinda E Medlyn
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Anna M Ukkola
- ARC Centre of Excellence for Climate Extremes, Sydney, NSW, Australia
- Research School of Earth Sciences, Australian National University, Canberra, ACT, Australia
| | - Mengyuan Mu
- ARC Centre of Excellence for Climate Extremes, Sydney, NSW, Australia
- Climate Change Research Centre, University of New South Wales, Sydney, NSW, Australia
| | - Manon E B Sabot
- ARC Centre of Excellence for Climate Extremes, Sydney, NSW, Australia
- Climate Change Research Centre, University of New South Wales, Sydney, NSW, Australia
- Evolution & Ecology Research Centre, University of New South Wales, Sydney, NSW, Australia
| | - Andrew J Pitman
- ARC Centre of Excellence for Climate Extremes, Sydney, NSW, Australia
- Climate Change Research Centre, University of New South Wales, Sydney, NSW, Australia
| | - Patrick Meir
- Research School of Biology, The Australian National University, Acton, ACT, Australia
- School of Geosciences, University of Edinburgh, Edinburgh, UK
| | - Lucas A Cernusak
- College of Science and Engineering, James Cook University, Cairns, Qld, Australia
| | - Sami W Rifai
- Climate Change Research Centre, University of New South Wales, Sydney, NSW, Australia
| | - Brendan Choat
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - David T Tissue
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Chris J Blackman
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Ximeng Li
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Michael Roderick
- ARC Centre of Excellence for Climate Extremes, Sydney, NSW, Australia
- Research School of Earth Sciences, Australian National University, Canberra, ACT, Australia
| | | |
Collapse
|
37
|
Affiliation(s)
- Timothy J. Brodribb
- School of Biological Sciences, University of Tasmania, Hobart, TAS 7001, Australia
| | - Jennifer Powers
- Departments of Ecology, Evolution and Behavior and Plant and Microbial Biology, University of Minnesota, 140 Gortner Laboratory, Saint Paul, MN 55108, USA
| | - Hervé Cochard
- Université Clermont Auvergne, INRAE, PIAF, 63000 Clermont-Ferrand, France
| | - Brendan Choat
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW 2751, Australia
| |
Collapse
|