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Zhang Q, Ma N, Su Y, Liu X. Characteristics of Growth, Photosynthesis, C/N Ratio, and Antioxidant Capacity in the Seedling Stage of Aquilaria sinensis 'Qinan'. PLANTS (BASEL, SWITZERLAND) 2025; 14:896. [PMID: 40265848 PMCID: PMC11945267 DOI: 10.3390/plants14060896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2025] [Revised: 03/09/2025] [Accepted: 03/11/2025] [Indexed: 04/24/2025]
Abstract
In this study, Aquilaria sinensis 'Qinan', a strain of A. sinensis that easily forms agarwood, was selected and propagated by grafting seedlings. Existing research has mainly focused on the characteristics of agarwood formation, but little attention has been paid to the growth characteristics of A. sinensis 'Qinan'. In this study, the growth rate, photosynthetic capacity, leaf size, carbon and nitrogen contents, and antioxidant capacity were evaluated during the early growth stage in A. sinensis 'Qinan' and A. sinensis grafted seedlings. Compared with A. sinensis, A. sinensis 'Qinan' exhibited higher net photosynthetic rate (9.2 μmol m-2 s-1 in A. sinensis 'Qinan' and 7.8 μmol m-2 s-1 in A. sinensis) in the mature leaf. There were higher contents of secondary metabolites such as flavonoids and phenols, with stronger antioxidant capacity in A. sinensis 'Qinan'. Larger leaf area (43.9 cm2 in A. sinensis and 30.1 cm2 in A. sinensis 'Qinan'), higher nitrogen content (24.9 mg kg-1 in A. sinensis and 23.7 mg kg-1 in A. sinensis 'Qinan') in young leaves, faster growth rate, and larger biomass were observed in A. sinensis. The results indicate that differences exist in nutrient distribution during the growth process of A. sinensis 'Qinan' and A. sinensis, with more substances being used to synthesize defensive secondary metabolites in A. sinensis 'Qinan'.
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Affiliation(s)
- Qilei Zhang
- Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou 510520, China; (Q.Z.)
- State Key Laboratory of Efficient Production of Forest Resources, Beijing 100091, China
| | - Ning Ma
- Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou 510520, China; (Q.Z.)
- College of Landscape Architecture, Nanjing Forestry University, Nanjing 210037, China
| | - Yu Su
- Guangzhou Institute of Forestry and Landscape Architecture, Guangzhou 510080, China
- Guangzhou Collaborative Innovation Center on Science-Tech of Ecology and Landscape, Guangzhou 510405, China
| | - Xiaojin Liu
- Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou 510520, China; (Q.Z.)
- State Key Laboratory of Efficient Production of Forest Resources, Beijing 100091, China
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2
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Guo JJ, Gong XW, Hao GY. Leaf Transpirational Cooling and Thermal Tolerance Vary Along the Spectrum of Iso-Anisohydric Stomatal Regulation in Sand-Fixing Shrubs. PLANT, CELL & ENVIRONMENT 2025; 48:2053-2066. [PMID: 39552528 DOI: 10.1111/pce.15279] [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: 06/30/2024] [Revised: 10/24/2024] [Accepted: 10/28/2024] [Indexed: 11/19/2024]
Abstract
Transpirational cooling is crucial for plant thermal regulation to avoid overheating; however, during prolonged and/or acute heat stress it often necessitates stomatal closure to reduce the risk of hydraulic failure due to dehydration. The intricate interplay between thermal regulation, water transport and use may govern plant performance in water-limited and simultaneously heat-stressed environments, yet this remains inadequately understood. Here, in a common garden, we evaluated the functional associations among physiological characteristics related to leaf thermoregulation, heat tolerance, xylem water transport, and stomatal regulation in eight shrub species commonly used for fixing active sand dunes in northern China. Our study showed that traits associated with heat adaptation and xylem hydraulics were closely related to stomatal regulation. More isohydric shrub species with higher water transport efficiency possessed stronger transpirational cooling capacity; whereas the more anisohydric species demonstrated greater tolerance to overheating. Moreover, leaf heat tolerance was strongly coordinated with drought tolerance reflected by leaf turgor loss point. These results underscore the importance of stomatal regulation in shaping plant thermal adaptive strategies and provide valuable insights into the coupling of water and heat-related physiological processes in plants adapted to sandy land environments prone to combined drought and heat stresses.
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Grants
- The study was supported by National Key R&D Program of China (2023YFF1304201), the National Natural Science Foundation of China (32471827, 32220103010, 32192431, and 31722013), the Major Program of Institute of Applied Ecology, Chinese Academy of Sciences (IAEMP202201), the Liaoning Provincial Science and Technology Major Project (2023JH1/10400001), the China Postdoctoral Science Foundation (2023M733674), the Project of Doctoral Research Startup Fund of Liaoning Province (2023-BS-021), the Youth Startup Fund of Institute of Applied Ecology, Chinese Academy of Sciences, and the Fund of CAS Key Laboratory of Forest Ecology and Silviculture, Institute of Applied Ecology, Chinese Academy of Sciences (KLFES-2025).
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Affiliation(s)
- Jing-Jing Guo
- CAS Key Laboratory of Forest Ecology and Silviculture, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
- Daqinggou Ecological Research Station, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
- Key Laboratory of Territorial Ecosystem Carbon Neutrality, Liaoning Province, Shenyang, China
| | - Xue-Wei Gong
- CAS Key Laboratory of Forest Ecology and Silviculture, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
- Daqinggou Ecological Research Station, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
- Key Laboratory of Territorial Ecosystem Carbon Neutrality, Liaoning Province, Shenyang, China
| | - Guang-You Hao
- CAS Key Laboratory of Forest Ecology and Silviculture, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
- Daqinggou Ecological Research Station, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
- Key Laboratory of Territorial Ecosystem Carbon Neutrality, Liaoning Province, Shenyang, China
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3
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Crous KY, Middleby KB, Cheesman AW, Bouet AYM, Schiffer M, Liddell MJ, Barton CVM, Cernusak LA. Leaf warming in the canopy of mature tropical trees reduced photosynthesis due to downregulation of photosynthetic capacity and reduced stomatal conductance. THE NEW PHYTOLOGIST 2025; 245:1421-1436. [PMID: 39644130 DOI: 10.1111/nph.20320] [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: 08/20/2024] [Accepted: 11/11/2024] [Indexed: 12/09/2024]
Abstract
Tropical forests play a large role in the global carbon cycle by annually absorbing 30% of our annual carbon emissions. However, these forests have evolved under relatively stable temperature conditions and may be sensitive to current climate warming. Few experiments have investigated the effects of warming on large, mature trees to better understand how higher temperatures affect these forests in situ. We targeted four tree species (Endiandra microneura, Castanospermum australe, Cleistanthus myrianthus and Myristica globosa) of the Australian tropical rainforest and warmed leaves in the canopy by 4°C for 8 months. We measured temperature response curves of photosynthesis and respiration, and determined the critical temperatures for chloroplast function based on Chl fluorescence. Both stomatal conductance and photosynthesis were strongly reduced by 48 and 35%, respectively, with warming. While reduced stomatal conductance was likely in response to higher vapour pressure deficit, the biochemistry of photosynthesis responded to higher temperatures via reduced Vcmax25 (-28%) and Jmax25 (-29%). There was no shift of the Topt of photosynthesis. Concurrently, respiration rates at a common temperature did not change in response to warming, suggesting limited respiratory thermal acclimation. This combination of physiological responses to leaf warming in mature tropical trees may suggest a reduced carbon sink with future warming in tropical forests.
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Affiliation(s)
- Kristine Y Crous
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, 2751, Australia
- School of Science, Western Sydney University, Penrith, NSW, 2751, Australia
| | - Kali B Middleby
- Centre for Tropical Environmental and Sustainability Science (TESS) and College of Science and Engineering, James Cook University, Cairns, Qld, 4878, Australia
| | - Alexander W Cheesman
- Centre for Tropical Environmental and Sustainability Science (TESS) and College of Science and Engineering, James Cook University, Cairns, Qld, 4878, Australia
| | - Angelina Y M Bouet
- Centre for Tropical Environmental and Sustainability Science (TESS) and College of Science and Engineering, James Cook University, Cairns, Qld, 4878, Australia
| | - Michele Schiffer
- Division of Research - Research Infrastructure, James Cook University, Cairns, Qld, 4878, Australia
| | - Michael J Liddell
- Centre for Tropical Environmental and Sustainability Science (TESS) and College of Science and Engineering, James Cook University, Cairns, Qld, 4878, Australia
| | - Craig V M Barton
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, 2751, Australia
| | - Lucas A Cernusak
- Centre for Tropical Environmental and Sustainability Science (TESS) and College of Science and Engineering, James Cook University, Cairns, Qld, 4878, Australia
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4
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Javad A, Premugh V, Tiwari R, Bandaru P, Sunny R, Hegde B, Clerici S, Galbraith D, Gloor M, Barua D. Leaf Temperatures in an Indian Tropical Forest Exceed Physiological Limits but Durations of Exposures Are Currently Not Sufficient to Cause Lasting Damage. GLOBAL CHANGE BIOLOGY 2025; 31:e70069. [PMID: 39925198 PMCID: PMC11808423 DOI: 10.1111/gcb.70069] [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: 06/19/2024] [Revised: 12/28/2024] [Accepted: 01/06/2025] [Indexed: 02/11/2025]
Abstract
Increasing temperatures in the tropics will reduce performance of trees and agroforestry species and may lead to lasting damage and leaf death. One criterion to determine future forest resilience is to evaluate damage caused by temperature on Photosystem-II (PSII), a particularly sensitive component of photosynthesis. The temperature at which 50% of PSII function is lost (T50) is a widely used measure of irreversible damage to leaves. To assess vulnerability to high temperatures, studies have measured T50 or leaf temperatures, but rarely both. Further, because extant leaf temperature records are short, duration of exposure above thresholds like T50 has not been considered. Finally, these studies do not directly assess the effect of threshold exceedance on leaves. To understand how often, and how long, leaf temperatures exceed critical thresholds, we measured leaf temperatures of forest and agroforestry species in a tropical forest in the Western Ghats of India where air temperatures are high. We quantified species-specific physiological thresholds and assessed leaf damage after high-temperature exposure. We found that leaf temperatures already exceed T50. However, continuous exposure durations above critical thresholds are very skewed with most events lasting for much less than 30 min. As T50 was measured after a 30-min exposure, our results suggest that threshold exceedances and exposure durations for lasting damage are currently not reached and will rarely be reached if maximum air temperatures increase by 4°C. Consistent with this, we found only minor indications of heat damage in the forest species. However, there were indications of heat-induced reduction in PSII function and damage in the agroforestry leaves which have lower T50. Our findings suggest that, for forest species, while high-temperature thresholds may be surpassed, durations of exposure above thresholds remain short, and therefore, are unlikely to lead to irreversible damage and leaf death, even under 4°C warming.
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Affiliation(s)
- Akhil Javad
- Department of BiologyIndian Institute of Science Education and ResearchPuneMaharashtraIndia
- School of GeographyUniversity of LeedsLeedsUK
| | - Vikhyath Premugh
- Department of BiologyIndian Institute of Science Education and ResearchPuneMaharashtraIndia
| | | | - Peddiraju Bandaru
- Department of BiologyIndian Institute of Science Education and ResearchPuneMaharashtraIndia
| | - Ron Sunny
- Department of BiologyIndian Institute of Science Education and ResearchPuneMaharashtraIndia
| | | | | | | | | | - Deepak Barua
- Department of BiologyIndian Institute of Science Education and ResearchPuneMaharashtraIndia
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5
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Cuervo-Gómez M, Melgarejo LM, Salgado-Negret B. Thermal acclimation of tree species in a tropical Andean city: Exploring the role of species origin and thermal niche. AMERICAN JOURNAL OF BOTANY 2025; 112:e16462. [PMID: 39871519 DOI: 10.1002/ajb2.16462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2024] [Revised: 11/08/2024] [Accepted: 11/11/2024] [Indexed: 01/29/2025]
Abstract
PREMISE The warmer and drier atmospheric conditions of urban environments challenge plant performance to different extents based on a species' ability to acclimate to the conditions. We evaluated the influence of species origin and thermal niche on the acclimation of leaf traits and shifts in the occupation of the functional trait space of 10 tree species growing in two environmentally contrasting sites in Bogotá, Colombia. METHODS We measured six leaf traits per species in both sites and used generalized linear models to evaluate the influence of origin and thermal niche on acclimation of leaf traits and t-tests to analyze shifts in the occupation of the functional trait space. RESULTS Species origin predicted thermal tolerance and morphological trait acclimation to warmer conditions. Although exotic species decreased thermal tolerance at the warmer site, species from both origins acclimated traits consistently. Shifts in the occupation of the functional trait space varied between origins; warmer conditions reduced the size of the functional trait space of exotics and increased the phenotypic similarity of natives. Thermal tolerance acclimation and changes in functional trait space varied across species. Finally, thermal niche metrics were uncoupled from species origin and failed to explain the acclimation capacity of the studied species. CONCLUSIONS Although species origin influenced acclimation to warmer conditions, the effect of origin was not related to species' thermal niches. Our results provide crucial information for decision-makers involved in designing urban and peri-urban green spaces that can withstand climate change.
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Affiliation(s)
- María Cuervo-Gómez
- Departamento de Biología, Universidad Nacional de Colombia, sede Bogotá, Colombia
| | - Luz Marina Melgarejo
- Departamento de Biología, Universidad Nacional de Colombia, sede Bogotá, Colombia
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6
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Middleby KB, Cheesman AW, Hopkinson R, Baker L, Ramirez Garavito S, Breed MF, Cernusak LA. Ecotypic Variation in Leaf Thermoregulation and Heat Tolerance but Not Thermal Safety Margins in Tropical Trees. PLANT, CELL & ENVIRONMENT 2025; 48:649-663. [PMID: 39318061 PMCID: PMC11615421 DOI: 10.1111/pce.15141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2024] [Revised: 07/31/2024] [Accepted: 08/22/2024] [Indexed: 09/26/2024]
Abstract
To avoid reaching lethal temperatures during periods of heat stress, plants may acclimate either their biochemical thermal tolerance or leaf morphological and physiological characteristics to reduce leaf temperature (Tleaf). While plants from warmer environments may have a greater capacity to regulate Tleaf, the extent of intraspecific variation and contribution of provenance is relatively unexplored. We tested whether upland and lowland provenances of four tropical tree species grown in a common garden differed in their thermal safety margins by measuring leaf thermal traits, midday leaf-to-air temperature differences (∆Tleaf) and critical leaf temperatures defined by chlorophyll fluorescence (Tcrit). Provenance variation was species- and trait-specific. Higher ∆Tleaf and Tcrit were observed in the lowland provenance for Terminalia microcarpa, and in the upland provenance for Castanospermum australe, with no provenance effects in the other two species. Within-species covariation of Tcrit and ∆Tleaf led to a convergence of thermal safety margins across provenances. While future studies should expand the number of provenances and species investigated, our findings suggest that lowland and upland provenances may not differ substantially in their vulnerability to heat stress, as determined by thermal safety margins, despite differences in operating temperatures and Tcrit.
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Affiliation(s)
- Kali B. Middleby
- College of Science and EngineeringJames Cook UniversityCairnsQueenslandAustralia
| | | | | | - Leesa Baker
- College of Science and EngineeringJames Cook UniversityCairnsQueenslandAustralia
| | | | - Martin F. Breed
- College of Science and EngineeringFlinders UniversityBedford ParkSouth AustraliaAustralia
| | - Lucas A. Cernusak
- College of Science and EngineeringJames Cook UniversityCairnsQueenslandAustralia
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7
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Martínez-Villa JA, Paquette A, Feeley KJ, Morales-Morales PA, Messier C, Durán SM. Changes in morphological and physiological traits of urban trees in response to elevated temperatures within an Urban Heat Island. TREE PHYSIOLOGY 2024; 44:tpae145. [PMID: 39541501 DOI: 10.1093/treephys/tpae145] [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: 04/27/2024] [Revised: 10/18/2024] [Accepted: 11/13/2024] [Indexed: 11/16/2024]
Abstract
Urban heat islands (UHIs) are a common phenomenon in metropolitan areas worldwide where the air temperature is significantly higher in urban areas than in surrounding suburban, rural or natural areas. Mitigation strategies to counteract UHI effects include increasing tree cover and green spaces to reduce heat. The successful application of these approaches necessitates a deep understanding of the thermal tolerances in urban trees and their susceptibility to elevated urban temperatures. We evaluated how the photosynthetic thermal optimum (Topt), photosynthetic heat tolerance (T50) and key leaf thermoregulatory morphological traits (leaf area [LA], specific leaf area, leaf width, thickness and leaf dry matter content) differ between conspecific trees growing in 'hot' (UHI) vs 'cool' parts of Montreal, Canada (with a difference of 3.4 °C in air temperature), to assess the ability of seven common tree species to acclimation to higher temperatures. We hypothesized that individuals with hotter growing temperatures would exhibit higher Topt and T50, as well as leaf thermoregulatory morphological traits aligned with conservative strategies (e.g., reduced LA and increased leaf mass) compared with their counterparts in the cooler parts of the city. Contrary to our a priori hypotheses, LA increased with growing temperatures and only four of the seven species had higher T50 and only three had higher Topt values in the hotter area. These results suggest that many tree species cannot acclimate to elevated temperatures and that the important services they provide, such as carbon capture, can be negatively affected by high temperatures caused by climate change and/or the UHI effect. The ability vs inability of tree species to acclimate to high temperatures should be considered when implementing long term tree planting programs in urban areas.
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Affiliation(s)
- Johanna Andrea Martínez-Villa
- Département des sciences biologiques, Centre for Forest Research, Université du Québec à Montréal, Montréal, Québec, 141 Av. du Président-Kennedy, Montréal, QC H2X 1Y4, Canada
| | - Alain Paquette
- Département des sciences biologiques, Centre for Forest Research, Université du Québec à Montréal, Montréal, Québec, 141 Av. du Président-Kennedy, Montréal, QC H2X 1Y4, Canada
| | - Kenneth J Feeley
- Biology Department, University of Miami, 1301 Memorial Dr #215, Coral Gables, FL 33146, United States
| | - Paula Andrea Morales-Morales
- Departamento de Ciencias Forestales, Universidad Nacional de Colombia - Sede Medellín, Medellin, Antioquia, Cra. 65 #59a-110, Medellín, Antioquia, Colombia
| | - Christian Messier
- Département des sciences biologiques, Centre for Forest Research, Université du Québec à Montréal, Montréal, Québec, 141 Av. du Président-Kennedy, Montréal, QC H2X 1Y4, Canada
| | - Sandra M Durán
- Department of Forest and Rangeland Stewardship, Colorado State University, 1472 Campus DeliveryFort Collins, CO 80523-1472, United States
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Eze C, Winter K, Slot M. Vapor-pressure-deficit-controlled temperature response of photosynthesis in tropical trees. PHOTOSYNTHETICA 2024; 62:318-325. [PMID: 39649359 PMCID: PMC11622557 DOI: 10.32615/ps.2024.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2024] [Accepted: 09/06/2024] [Indexed: 12/10/2024]
Abstract
Rising temperatures can affect stomatal and nonstomatal control over photosynthesis, through stomatal closure in response to increasing vapor pressure deficit (VPD), and biochemical limitations, respectively. To explore the independent effects of temperature and VPD, we conducted leaf-level temperature-response measurements while controlling VPD on three tropical tree species. Photosynthesis and stomatal conductance consistently decreased with increasing VPD, whereas photosynthesis typically responded weakly to changes in temperature when a stable VPD was maintained during measurements, resulting in wide parabolic temperature-response curves. We have shown that the negative effect of temperature on photosynthesis in tropical forests across ecologically important temperature ranges does not stem from direct warming effects on biochemical processes but from the indirect effect of warming, through changes in VPD. Understanding the acclimation potential of tropical trees to elevated VPD will be critical to anticipate the consequences of global warming for tropical forests.
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Affiliation(s)
- C.E. Eze
- Smithsonian Tropical Research Institute, Apartado 0843-03092, Balboa, Ancón, Republic of Panama
- Department of Agronomy, Michael Okpara University of Agriculture Umudike, Abia State 440109, Nigeria
| | - K. Winter
- Smithsonian Tropical Research Institute, Apartado 0843-03092, Balboa, Ancón, Republic of Panama
| | - M. Slot
- Smithsonian Tropical Research Institute, Apartado 0843-03092, Balboa, Ancón, Republic of Panama
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9
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Manzi OJL, Wittemann M, Dusenge ME, Habimana J, Manishimwe A, Mujawamariya M, Ntirugulirwa B, Zibera E, Tarvainen L, Nsabimana D, Wallin G, Uddling J. Canopy temperatures strongly overestimate leaf thermal safety margins of tropical trees. THE NEW PHYTOLOGIST 2024; 243:2115-2129. [PMID: 39073111 DOI: 10.1111/nph.20013] [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: 02/29/2024] [Accepted: 07/07/2024] [Indexed: 07/30/2024]
Abstract
Current estimates of temperature effects on plants mostly rely on air temperature, although it can significantly deviate from leaf temperature (Tleaf). To address this, some studies have used canopy temperature (Tcan). However, Tcan fails to capture the fine-scale variation in Tleaf among leaves and species in diverse canopies. We used infrared radiometers to study Tleaf and Tcan and how they deviate from air temperature (ΔTleaf and ΔTcan) in multispecies tropical tree plantations at three sites along an elevation and temperature gradient in Rwanda. Our results showed high Tleaf (up to c. 50°C) and ΔTleaf (on average 8-10°C and up to c. 20°C) of sun-exposed leaves during 10:00 h-15:00 h, being close to or exceeding photosynthetic heat tolerance thresholds. These values greatly exceeded simultaneously measured values of Tcan and ΔTcan, respectively, leading to strongly overestimated leaf thermal safety margins if basing those on Tcan data. Stomatal conductance and leaf size affected Tleaf and Tcan in line with their expected influences on leaf energy balance. Our findings highlight the importance of leaf traits for leaf thermoregulation and show that monitoring Tcan is not enough to capture the peak temperatures and heat stress experienced by individual leaves of different species in tropical forest canopies.
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Affiliation(s)
- Olivier Jean Leonce Manzi
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 463, Gothenburg, SE-405 30, Sweden
- Integrated Polytechnic Regional College-Kitabi, Rwanda Polytechnic, PO Box 330, Huye, Rwanda
| | - Maria Wittemann
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 463, Gothenburg, SE-405 30, Sweden
| | - Mirindi Eric Dusenge
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 463, Gothenburg, SE-405 30, Sweden
- Department of Biology, Mount Allison University, Sackville, NB, E4L 1E4, Canada
| | - Jacques Habimana
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 463, Gothenburg, SE-405 30, Sweden
| | - Aloysie Manishimwe
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 463, Gothenburg, SE-405 30, Sweden
- Department of Biology, College of Science and Technology, University of Rwanda, Avenue de l'Armée, PO Box 3900, Kigali, Rwanda
| | - Myriam Mujawamariya
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 463, Gothenburg, SE-405 30, Sweden
- Department of Biology, College of Science and Technology, University of Rwanda, Avenue de l'Armée, PO Box 3900, Kigali, Rwanda
| | - Bonaventure Ntirugulirwa
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 463, Gothenburg, SE-405 30, Sweden
- Department of Biology, College of Science and Technology, University of Rwanda, Avenue de l'Armée, PO Box 3900, Kigali, Rwanda
- Rwanda Agriculture and Animal Resources Development Board, PO Box 5016, Kigali, Rwanda
- Rwanda Forestry Authority, PO Box 46, Muhanga, Rwanda
| | - Etienne Zibera
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 463, Gothenburg, SE-405 30, Sweden
- School of Agriculture and Food Sciences, College of Agriculture, Animal Sciences and Veterinary Medicine, University of Rwanda, PO Box 210, Musanze, Rwanda
| | - Lasse Tarvainen
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 463, Gothenburg, SE-405 30, Sweden
| | - Donat Nsabimana
- School of Forestry and Biodiversity Conservation, College of Agriculture, Animal Sciences and Veterinary Medicine, University of Rwanda, PO Box 210, Musanze, Rwanda
| | - Göran Wallin
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 463, Gothenburg, SE-405 30, Sweden
| | - Johan Uddling
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 463, Gothenburg, SE-405 30, Sweden
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10
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Gauthey A, Kahmen A, Limousin JM, Vilagrosa A, Didion-Gency M, Mas E, Milano A, Tunas A, Grossiord C. High heat tolerance, evaporative cooling, and stomatal decoupling regulate canopy temperature and their safety margins in three European oak species. GLOBAL CHANGE BIOLOGY 2024; 30:e17439. [PMID: 39092538 DOI: 10.1111/gcb.17439] [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: 02/15/2024] [Revised: 06/03/2024] [Accepted: 07/08/2024] [Indexed: 08/04/2024]
Abstract
Heatwaves and soil droughts are increasing in frequency and intensity, leading many tree species to exceed their thermal thresholds, and driving wide-scale forest mortality. Therefore, investigating heat tolerance and canopy temperature regulation mechanisms is essential to understanding and predicting tree vulnerability to hot droughts. We measured the diurnal and seasonal variation in leaf water potential (Ψ), gas exchange (photosynthesis Anet and stomatal conductance gs), canopy temperature (Tcan), and heat tolerance (leaf critical temperature Tcrit and thermal safety margins TSM, i.e., the difference between maximum Tcan and Tcrit) in three oak species in forests along a latitudinal gradient (Quercus petraea in Switzerland, Quercus ilex in France, and Quercus coccifera in Spain) throughout the growing season. Gas exchange and Ψ of all species were strongly reduced by increased air temperature (Tair) and soil drying, resulting in stomatal closure and inhibition of photosynthesis in Q. ilex and Q. coccifera when Tair surpassed 30°C and soil moisture dropped below 14%. Across all seasons, Tcan was mainly above Tair but increased strongly (up to 10°C > Tair) when Anet was null or negative. Although trees endured extreme Tair (up to 42°C), positive TSM were maintained during the growing season due to high Tcrit in all species (average Tcrit of 54.7°C) and possibly stomatal decoupling (i.e., Anet ≤0 while gs >0). Indeed, Q. ilex and Q. coccifera trees maintained low but positive gs (despite null Anet), decreasing Ψ passed embolism thresholds. This may have prevented Tcan from rising above Tcrit during extreme heat. Overall, our work highlighted that the mechanisms behind heat tolerance and leaf temperature regulation in oak trees include a combination of high evaporative cooling, large heat tolerance limits, and stomatal decoupling. These processes must be considered to accurately predict plant damages, survival, and mortality during extreme heatwaves.
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Affiliation(s)
- Alice Gauthey
- Plant Ecology Research Laboratory PERL, School of Architecture, Civil and Environmental Engineering, EPFL, Lausanne, Switzerland
- Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Birmingham Institute of Forest Research, University of Birmingham, Birmingham, UK
| | - Ansgar Kahmen
- Physiological Plant Ecology, Department of Environmental Sciences, University of Basel, Basel, Switzerland
| | - Jean-Marc Limousin
- Centre d'Ecologie Fonctionnelle et Evolutive, CNRS, EPHE, IRD, Université de Montpellier, Montpellier, France
| | - Alberto Vilagrosa
- CEAM Foundation, Joint Research Unit University of Alicante-CEAM, Department Ecology, University of Alicante, Alicante, Spain
| | - Margaux Didion-Gency
- Forest Dynamics Unit, Swiss Federal Institute for Forest, Snow and Landscape WSL, Birmensdorf, Switzerland
| | - Eugénie Mas
- Plant Ecology Research Laboratory PERL, School of Architecture, Civil and Environmental Engineering, EPFL, Lausanne, Switzerland
- Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Forest Global Earth Observatory, Smithsonian Tropical Research Institute, Washington, District of Columbia, USA
| | - Arianna Milano
- Plant Ecology Research Laboratory PERL, School of Architecture, Civil and Environmental Engineering, EPFL, Lausanne, Switzerland
- Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Alex Tunas
- Plant Ecology Research Laboratory PERL, School of Architecture, Civil and Environmental Engineering, EPFL, Lausanne, Switzerland
- Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
- Department of Ecology, University of Innsbruck, Innsbruck, Austria
| | - Charlotte Grossiord
- Plant Ecology Research Laboratory PERL, School of Architecture, Civil and Environmental Engineering, EPFL, Lausanne, Switzerland
- Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
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11
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Middleby KB, Cheesman AW, Cernusak LA. Impacts of elevated temperature and vapour pressure deficit on leaf gas exchange and plant growth across six tropical rainforest tree species. THE NEW PHYTOLOGIST 2024; 243:648-661. [PMID: 38757766 DOI: 10.1111/nph.19822] [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: 12/16/2023] [Accepted: 04/30/2024] [Indexed: 05/18/2024]
Abstract
Elevated air temperature (Tair) and vapour pressure deficit (VPDair) significantly influence plant functioning, yet their relative impacts are difficult to disentangle. We examined the effects of elevated Tair (+6°C) and VPDair (+0.7 kPa) on the growth and physiology of six tropical tree species. Saplings were grown under well-watered conditions in climate-controlled glasshouses for 6 months under three treatments: (1) low Tair and low VPDair, (2) high Tair and low VPDair, and (3) high Tair and high VPDair. To assess acclimation, physiological parameters were measured at a set temperature. Warm-grown plants grown under elevated VPDair had significantly reduced stomatal conductance and increased instantaneous water use efficiency compared to plants grown under low VPDair. Photosynthetic biochemistry and thermal tolerance (Tcrit) were unaffected by VPDair, but elevated Tair caused Jmax25 to decrease and Tcrit to increase. Sapling biomass accumulation for all species responded positively to an increase in Tair, but elevated VPDair limited growth. This study shows that stomatal limitation caused by even moderate increases in VPDair can decrease productivity and growth rates in tropical species independently from Tair and has important implications for modelling the impacts of climate change on tropical forests.
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Affiliation(s)
- Kali B Middleby
- College of Science and Engineering, James Cook University, Cairns, QLD, 4878, Australia
| | - Alexander W Cheesman
- College of Science and Engineering, James Cook University, Cairns, QLD, 4878, Australia
| | - Lucas A Cernusak
- College of Science and Engineering, James Cook University, Cairns, QLD, 4878, Australia
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12
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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.
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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
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13
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Bison NN, Michaletz ST. Variation in leaf carbon economics, energy balance, and heat tolerance traits highlights differing timescales of adaptation and acclimation. THE NEW PHYTOLOGIST 2024. [PMID: 38532535 DOI: 10.1111/nph.19702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 03/06/2024] [Indexed: 03/28/2024]
Abstract
Multivariate leaf trait correlations are hypothesized to originate from natural selection on carbon economics traits that control lifetime leaf carbon gain, and energy balance traits governing leaf temperatures, physiological rates, and heat injury. However, it is unclear whether macroevolution of leaf traits primarily reflects selection for lifetime carbon gain or energy balance, and whether photosynthetic heat tolerance is coordinated along these axes. To evaluate these hypotheses, we measured carbon economics, energy balance, and photosynthetic heat tolerance traits for 177 species (157 families) in a common garden that minimizes co-variation of taxa and climate. We observed wide variation in carbon economics, energy balance, and heat tolerance traits. Carbon economics and energy balance (but not heat tolerance) traits were phylogenetically structured, suggesting macroevolution of leaf mass per area and leaf dry matter content reflects selection on carbon gain rather than energy balance. Carbon economics and energy balance traits varied along a common axis orthogonal to heat tolerance traits. Our results highlight a fundamental mismatch in the timescales over which morphological and heat tolerance traits respond to environmental variation. Whereas carbon economics and energy balance traits are constrained by species' evolutionary histories, photosynthetic heat tolerance traits are not and can acclimate readily to leaf microclimates.
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Affiliation(s)
- Nicole N Bison
- Department of Botany, The University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
- Biodiversity Research Centre, The University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Sean T Michaletz
- Department of Botany, The University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
- Biodiversity Research Centre, The University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
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14
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Song X, Gu J, Ye Y, Wang M, Wang R, Ma H, Shao X. Exploring Intraspecific Trait Variation in a Xerophytic Moss Species Indusiella thianschanica (Ptychomitriaceae) across Environmental Gradients on the Tibetan Plateau. PLANTS (BASEL, SWITZERLAND) 2024; 13:921. [PMID: 38611451 PMCID: PMC11013618 DOI: 10.3390/plants13070921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2024] [Revised: 03/12/2024] [Accepted: 03/13/2024] [Indexed: 04/14/2024]
Abstract
Investigating intraspecific trait variability is crucial for understanding plant adaptation to various environments, yet research on lithophytic mosses in extreme environments remains scarce. This study focuses on Indusiella thianschanica Broth. Hal., a unique lithophytic moss species in the extreme environments of the Tibetan Plateau, aiming to uncover its adaptation and response mechanisms to environmental changes. Specimens were collected from 26 sites across elevations ranging from 3642 m to 5528 m, and the relationships between 23 morphological traits and 15 environmental factors were analyzed. Results indicated that coefficients of variation (CV) ranged from 5.91% to 36.11%, with gametophyte height (GH) and basal cell transverse wall thickness (STW) showing the highest and lowest variations, respectively. Temperature, elevation, and potential evapo-transpiration (PET) emerged as primary environmental drivers. Leaf traits, especially those of the leaf sheath, exhibited a more pronounced response to the environment. The traits exhibited apparent covariation in response to environmental challenges and indicated flexible adaptive strategies. This study revealed the adaptation and response patterns of different morphological traits of I. thianschanica to environmental changes on the Tibetan Plateau, emphasizing the significant effect of temperature on trait variation. Our findings deepen the understanding of the ecology and adaptive strategies of lithophytic mosses.
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Affiliation(s)
- Xiaotong Song
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; (X.S.); (J.G.); (M.W.)
- Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing 100193, China
| | - Jiqi Gu
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; (X.S.); (J.G.); (M.W.)
- Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing 100193, China
- State Key Laboratory of Earth Surface Processes and Resource Ecology, College of Life Sciences, Beijing Normal University, Beijing 100875, China
| | - Yanhui Ye
- Resources & Environment College, Tibet Agriculture & Animal Husbandry University, Nyingchi 860000, China;
| | - Mengzhen Wang
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; (X.S.); (J.G.); (M.W.)
- Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing 100193, China
| | - Ruihong Wang
- Institute of Tibet Plateau Ecology, Tibet Agricultural & Animal Husbandry University, Nyingchi 860000, China; (R.W.); (H.M.)
- Key Laboratory of Forest Ecology in Tibet Plateau, Tibet Agricultural & Animal Husbandry University, Ministry of Education, Nyingchi 860000, China
| | - Heping Ma
- Institute of Tibet Plateau Ecology, Tibet Agricultural & Animal Husbandry University, Nyingchi 860000, China; (R.W.); (H.M.)
- Key Laboratory of Forest Ecology in Tibet Plateau, Tibet Agricultural & Animal Husbandry University, Ministry of Education, Nyingchi 860000, China
| | - Xiaoming Shao
- College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; (X.S.); (J.G.); (M.W.)
- Beijing Key Laboratory of Biodiversity and Organic Farming, China Agricultural University, Beijing 100193, China
- Resources & Environment College, Tibet Agriculture & Animal Husbandry University, Nyingchi 860000, China;
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15
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Ning QR, Li Q, Zhang HP, Jin Y, Gong XW, Jiao RF, Bakpa EP, Zhao H, Liu H. Weak correlations among leaf thermal metrics, economic traits and damages under natural heatwaves. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 916:170022. [PMID: 38220006 DOI: 10.1016/j.scitotenv.2024.170022] [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: 11/13/2023] [Revised: 12/29/2023] [Accepted: 01/07/2024] [Indexed: 01/16/2024]
Abstract
The frequency and intensity of heatwaves are increasing around the world, causing severe damages to plants, but whether leaf thermal metrics is in line with leaf economic spectrum is still controversial. Here, we measured leaf damage ratio, leaf thermal metrics (tolerance and sensitivity) and economic traits of 131 woody species across five cities along the Yangtze River after a two-month natural extreme temperature event. We found that leaf thermal sensitivity but not thermal tolerance was correlated with leaf damage ratio, and the relationships between leaf thermal metrics and economic traits were weak, indicating that leaf thermal adaptation may be independent from leaf carbon construction. This study suggests a potential indicator for predicting plant survival under heatwaves, urging future research to explore more physiological traits to comprehensively understand plant heat responses and adaptations.
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Affiliation(s)
- Qiu-Rui Ning
- Guangdong Provincial Key Laboratory of Applied Botany, Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, State Key Laboratory of Plant Diversity and Specialty Crops, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China; Key Laboratory of National Forestry and Grassland Administration on Plant Conservation and Utilization in Southern China, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Qiang Li
- School of Tropical Medicine, Hainan Medical University, Haikou, China
| | - Hao-Ping Zhang
- Guangdong Provincial Key Laboratory of Applied Botany, Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, State Key Laboratory of Plant Diversity and Specialty Crops, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China; Key Laboratory of National Forestry and Grassland Administration on Plant Conservation and Utilization in Southern China, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Yi Jin
- Lushan Botanical Garden, Chinese Academy of Sciences, Jiujiang, China
| | - Xue-Wei Gong
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
| | - Rui-Fang Jiao
- Guangdong Provincial Key Laboratory of Applied Botany, Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, State Key Laboratory of Plant Diversity and Specialty Crops, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China; Key Laboratory of National Forestry and Grassland Administration on Plant Conservation and Utilization in Southern China, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Emily Patience Bakpa
- Guangdong Provincial Key Laboratory of Applied Botany, Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, State Key Laboratory of Plant Diversity and Specialty Crops, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China; Key Laboratory of National Forestry and Grassland Administration on Plant Conservation and Utilization in Southern China, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Han Zhao
- Guangdong Provincial Key Laboratory of Applied Botany, Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, State Key Laboratory of Plant Diversity and Specialty Crops, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Hui Liu
- Guangdong Provincial Key Laboratory of Applied Botany, Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, State Key Laboratory of Plant Diversity and Specialty Crops, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China; Key Laboratory of National Forestry and Grassland Administration on Plant Conservation and Utilization in Southern China, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China.
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16
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Cox AJF, González-Caro S, Meir P, Hartley IP, Restrepo Z, Villegas JC, Sanchez A, Mercado LM. Variable thermal plasticity of leaf functional traits in Andean tropical montane forests. PLANT, CELL & ENVIRONMENT 2024; 47:731-750. [PMID: 38047584 DOI: 10.1111/pce.14778] [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: 06/14/2023] [Revised: 11/08/2023] [Accepted: 11/21/2023] [Indexed: 12/05/2023]
Abstract
Tropical montane forests (TMFs) are biodiversity hotspots and provide vital ecosystem services, but they are disproportionately vulnerable to climate warming. In the Andes, cold-affiliated species from high elevations are being displaced at the hot end of their thermal distributions by warm-affiliated species migrating upwards from lower elevations, leading to compositional shifts. Leaf functional traits are strong indicators of plant performance and at the community level have been shown to vary along elevation gradients, reflecting plant adaptations to different environmental niches. However, the plastic response of such traits to relatively rapid temperature change in Andean TMF species remains unknown. We used three common garden plantations within a thermosequence in the Colombian Andes to investigate the warming and cooling responses of key leaf functional traits in eight cold- and warm-affiliated species with variable thermal niches. Cold-affiliated species shifted their foliar nutrient concentrations when exposed to warming, while all other traits did not significantly change; contrastingly, warm-affiliated species were able to adjust structural, nutrient and water-use efficiency traits from acquisitive to conservative strategies in response to cooling. Our findings suggest that cold-affiliated species will struggle to acclimate functional traits to warming, conferring warm-affiliated species a competitive advantage under climate change.
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Affiliation(s)
- Andrew J F Cox
- Department of Geography, Faculty of Environment, Science and Economy, University of Exeter, Exeter, UK
| | - Sebastián González-Caro
- Department of Geography, Faculty of Environment, Science and Economy, University of Exeter, Exeter, UK
| | - Patrick Meir
- School of Geosciences, University of Edinburgh, Edinburgh, UK
- Division of Plant Sciences, Research, The Australian National University, Canberra, Australia
| | - Iain P Hartley
- Department of Geography, Faculty of Environment, Science and Economy, University of Exeter, Exeter, UK
| | - Zorayda Restrepo
- Grupo de Investigación en Ecología Aplicada, Universidad de Antioquia, Medellín, Colombia
- Grupo de Servicios Ecositémicos y Cambio Climático, Corporación, Medellín, Colombia
| | - Juan C Villegas
- Grupo de Investigación en Ecología Aplicada, Universidad de Antioquia, Medellín, Colombia
| | - Adriana Sanchez
- Programa de Biología, Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
| | - Lina M Mercado
- Department of Geography, Faculty of Environment, Science and Economy, University of Exeter, Exeter, UK
- UK Centre for Ecology & Hydrology, Crowmarsh-Gifford, Wallingford, UK
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17
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Gao T, Zhang D, Shen W, Xu S, Jia X, Liu X, Tan K, Zhou Y, Zhang Z, Ma F, Li C. MdASMT9-mediated melatonin biosynthesis enhances basal thermotolerance in apple plants. PLANT, CELL & ENVIRONMENT 2024; 47:751-764. [PMID: 38164091 DOI: 10.1111/pce.14791] [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: 09/03/2023] [Revised: 11/26/2023] [Accepted: 12/11/2023] [Indexed: 01/03/2024]
Abstract
High temperatures negatively impact the yield and quality of fruit crops. Exogenous melatonin (MT) application has been shown to enhance heat tolerance, but the response of endogenous MT to heat stress, particularly in perennial fruit trees, remains unclear. The present study investigated the effects of high temperatures on transgenic apple plants overexpressing the MT biosynthesis gene N-acetylserotonin methyltransferase 9 (MdASMT9). Endogenous MT protected transgenic plants from heat stress by increasing antioxidant enzyme activity and scavenging reactive oxygen species (ROS), and protecting the chloroplasts from damage. Application of MT and overexpression of MdASMT9 also reduced abscisic acid accumulation through promoting MdWRKY33-mediated transcriptional inhibition of MdNCED1 and MdNCED3, thus inducing stomatal opening for better heat dissipation. Furthermore, MT-enhanced autophagic activity through promoting MdWRKY33-mediated transcriptional enhancement of MdATG18a under heat stress. These findings provide new insights into the regulation of endogenous MT and its role in improving basal thermotolerance in perennial fruit trees.
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Affiliation(s)
- Tengteng Gao
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production/Shaanxi Key Laboratory of Apple, Pomology Department, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, China
| | - Danni Zhang
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production/Shaanxi Key Laboratory of Apple, Pomology Department, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, China
| | - Wentao Shen
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production/Shaanxi Key Laboratory of Apple, Pomology Department, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, China
| | - Shuo Xu
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production/Shaanxi Key Laboratory of Apple, Pomology Department, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, China
| | - Xumei Jia
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production/Shaanxi Key Laboratory of Apple, Pomology Department, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, China
| | - Xiaomin Liu
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production/Shaanxi Key Laboratory of Apple, Pomology Department, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, China
| | - Kexin Tan
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production/Shaanxi Key Laboratory of Apple, Pomology Department, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, China
| | - Yi Zhou
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production/Shaanxi Key Laboratory of Apple, Pomology Department, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, China
| | - Zhijun Zhang
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production/Shaanxi Key Laboratory of Apple, Pomology Department, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, China
| | - Fengwang Ma
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production/Shaanxi Key Laboratory of Apple, Pomology Department, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, China
| | - Chao Li
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production/Shaanxi Key Laboratory of Apple, Pomology Department, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, China
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18
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Wei L, Sanczuk P, De Pauw K, Caron MM, Selvi F, Hedwall PO, Brunet J, Cousins SAO, Plue J, Spicher F, Gasperini C, Iacopetti G, Orczewska A, Uria-Diez J, Lenoir J, Vangansbeke P, De Frenne P. Using warming tolerances to predict understory plant responses to climate change. GLOBAL CHANGE BIOLOGY 2024; 30:e17064. [PMID: 38273565 DOI: 10.1111/gcb.17064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 10/27/2023] [Accepted: 11/06/2023] [Indexed: 01/27/2024]
Abstract
Climate change is pushing species towards and potentially beyond their critical thermal limits. The extent to which species can cope with temperatures exceeding their critical thermal limits is still uncertain. To better assess species' responses to warming, we compute the warming tolerance (ΔTniche ) as a thermal vulnerability index, using species' upper thermal limits (the temperature at the warm limit of their distribution range) minus the local habitat temperature actually experienced at a given location. This metric is useful to predict how much more warming species can tolerate before negative impacts are expected to occur. Here we set up a cross-continental transplant experiment involving five regions distributed along a latitudinal gradient across Europe (43° N-61° N). Transplant sites were located in dense and open forests stands, and at forest edges and in interiors. We estimated the warming tolerance for 12 understory plant species common in European temperate forests. During 3 years, we examined the effects of the warming tolerance of each species across all transplanted locations on local plant performance, in terms of survival, height, ground cover, flowering probabilities and flower number. We found that the warming tolerance (ΔTniche ) of the 12 studied understory species was significantly different across Europe and varied by up to 8°C. In general, ΔTniche were smaller (less positive) towards the forest edge and in open stands. Plant performance (growth and reproduction) increased with increasing ΔTniche across all 12 species. Our study demonstrated that ΔTniche of understory plant species varied with macroclimatic differences among regions across Europe, as well as in response to forest microclimates, albeit to a lesser extent. Our findings support the hypothesis that plant performance across species decreases in terms of growth and reproduction as local temperature conditions reach or exceed the warm limit of the focal species.
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Affiliation(s)
- Liping Wei
- CAS Engineering Laboratory for Vegetation Ecosystem Restoration on Islands and Coastal Zones, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
- Forest & Nature Lab, Department of Environment, Faculty of Bioscience Engineering, Ghent University, Melle-Gontrode, Belgium
| | - Pieter Sanczuk
- Forest & Nature Lab, Department of Environment, Faculty of Bioscience Engineering, Ghent University, Melle-Gontrode, Belgium
| | - Karen De Pauw
- Forest & Nature Lab, Department of Environment, Faculty of Bioscience Engineering, Ghent University, Melle-Gontrode, Belgium
| | - Maria Mercedes Caron
- Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto Multidisciplinario de Biología Vegetal (IMBIV), CONICET, Córdoba, Argentina
- European Forest Institute-Mediterranean Facility, Barcelona, Spain
| | - Federico Selvi
- Department of Agriculture, Food, Environment and Forestry, University of Florence, Florence, Italy
| | - Per-Ola Hedwall
- Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences, Lomma, Sweden
| | - Jörg Brunet
- Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences, Lomma, Sweden
| | - Sara A O Cousins
- Landscapes, Environment and Geomatics, Department of Physical Geography, Stockholm University, Stockholm, Sweden
| | - Jan Plue
- Department of Urban and Rural Development, SLU Swedish Biodiversity Centre (CBM), Institutionen för stad och land, Uppsala, Sweden
| | - Fabien Spicher
- UMR CNRS 7058 Ecologie et Dynamique des Systèmes Anthropisés (EDYSAN), Université de Picardie Jules Verne, Amiens, France
| | - Cristina Gasperini
- Department of Agriculture, Food, Environment and Forestry, University of Florence, Florence, Italy
| | - Giovanni Iacopetti
- Department of Agriculture, Food, Environment and Forestry, University of Florence, Florence, Italy
| | - Anna Orczewska
- Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia, Katowice, Poland
| | - Jaime Uria-Diez
- Department of Forest Sciences, NEIKER-Basque Institute for Agricultural Research and Development, Basque Research and Technology Alliance (BRTA), Derio, Spain
| | - Jonathan Lenoir
- UMR CNRS 7058 Ecologie et Dynamique des Systèmes Anthropisés (EDYSAN), Université de Picardie Jules Verne, Amiens, France
| | - Pieter Vangansbeke
- Forest & Nature Lab, Department of Environment, Faculty of Bioscience Engineering, Ghent University, Melle-Gontrode, Belgium
- Earth and Life Institute, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Pieter De Frenne
- Forest & Nature Lab, Department of Environment, Faculty of Bioscience Engineering, Ghent University, Melle-Gontrode, Belgium
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19
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Qu LP, Chen J, Xiao J, De Boeck HJ, Dong G, Jiang SC, Hu YL, Wang YX, Shao CL. The complexity of heatwaves impact on terrestrial ecosystem carbon fluxes: Factors, mechanisms and a multi-stage analytical approach. ENVIRONMENTAL RESEARCH 2024; 240:117495. [PMID: 37890820 DOI: 10.1016/j.envres.2023.117495] [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: 08/25/2023] [Revised: 10/23/2023] [Accepted: 10/23/2023] [Indexed: 10/29/2023]
Abstract
Extreme heatwaves have become more frequent and severe in recent decades, and are expected to significantly influence carbon fluxes at regional scales across global terrestrial ecosystems. Nevertheless, accurate prediction of future heatwave impacts remains challenging due to a lack of a consistent comprehension of intrinsic and extrinsic mechanisms. We approached this knowledge gap by analyzing the complexity factors in heatwave studies, including the methodology for determining heatwave events, divergent responses of individual ecosystem components at multiple ecological and temporal scales, and vegetation status and hydrothermal environment, among other factors. We found that heatwaves essentially are continuously changing compound environmental stress that can unfold into multiple chronological stages, and plant physiology and carbon flux responses differs in each of these stages. This approach offers a holistic perspective, recognizing that the impacts of heatwaves on ecosystems can be better understood when evaluated over time. These stages include instantaneous, post-heatwave, legacy, and cumulative effects, each contributing uniquely to the overall impact on the ecosystem carbon cycle. Next, we investigated the importance of the timing of heatwaves and the possible divergent consequences caused by different annual heatwave patterns. Finally, a conceptual framework is proposed to establish a united foundation for the study and comprehension of the consequences of heatwaves on ecosystem carbon cycle. This instrumental framework will assist in guiding regional assessments of heatwave impacts, shedding light on the underlying mechanisms responsible for the varied responses of terrestrial ecosystems to specific heatwave events, which are imperative for devising efficient adaptation and mitigation approaches.
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Affiliation(s)
- Lu-Ping Qu
- College of JunCao Science and Ecology, Fujian Agriculture and Forestry University, Fuzhou, China.
| | - Jiquan Chen
- Center for Global Change & Earth Observations (CGCEO), Michigan State University, East Lansing, MI, 48823, USA.
| | - Jingfeng Xiao
- Earth Systems Research Center, Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, NH, 03824, USA.
| | - Hans J De Boeck
- Research Group of Plants and Ecosystems (PLECO), Department of Biology, University of Antwerp, 2610, Wilrijk, Belgium.
| | - Gang Dong
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China; School of Life Science, Shanxi University, Taiyuan, China.
| | | | - Ya-Lin Hu
- College of JunCao Science and Ecology, Fujian Agriculture and Forestry University, Fuzhou, China.
| | - Yi-Xuan Wang
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
| | - Chang-Liang Shao
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
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20
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Chen X, Li J, Peñuelas J, Li X, Hu D, Wang M, Zhong Q, Cheng D. Temperature dependence of carbon metabolism in the leaves in sun and shade in a subtropical forest. Oecologia 2024; 204:59-69. [PMID: 38091103 DOI: 10.1007/s00442-023-05487-7] [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: 05/20/2023] [Accepted: 11/15/2023] [Indexed: 02/02/2024]
Abstract
Rising temperatures pose a threat to the stability of climate regulation by carbon metabolism in subtropical forests. Although the effects of temperature on leaf carbon metabolism traits in sun-exposed leaves are well understood, there is limited knowledge about its impacts on shade leaves and the implications for ecosystem-climate feedbacks. In this study, we measured temperature response curves of photosynthesis and respiration for 62 woody species in summer (including both evergreen and deciduous species) and 20 evergreen species in winter. The aim was to uncover the temperature dependence of carbon metabolism in both sun and shade leaves in subtropical forests. Our findings reveal that shade had no significant effects on the mean optimum photosynthetic temperatures (TOpt) or temperature range (T90). However, there were decreases observed in mean stomatal conductance, mean area-based photosynthetic rates at TOpt and 25 °C, as well as mean area-based dark respiration rates at 25 °C in both evergreen and deciduous species. Moreover, the respiration-temperature sensitivity (Q10) of sun leaves was higher than that of shade leaves in winter, with the reverse being true in summer. Leaf economics spectrum traits, such as leaf mass per area, and leaf concentration of nitrogen and phosphorus across species, proved to be good predictors of TOpt, T90, mass-based photosynthetic rate at TOpt, and mass-based photosynthetic and respiration rate at 25 °C. However, Q10 was poorly predicted by these leaf economics spectrum traits except for shade leaves in winter. Our results suggest that model estimates of carbon metabolism in multilayered subtropical forest canopies do not necessitate independent parameterization of T90 and TOpt temperature responses in sun and shade leaves. Nevertheless, a deeper understanding and quantification of canopy variations in Q10 responses to temperature are necessary to confirm the generality of temperature-carbon metabolism trait responses and enhance ecosystem model estimates of carbon dynamics under future climate warming.
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Affiliation(s)
- Xiaoping Chen
- Key Laboratory of Humid Subtropical Eco-Geographical Process (Ministry of Education), College of Geographical Sciences, Fujian Normal University, Fuzhou, China
- College of Tourism, Resources and Environment, Zaozhuang University, Zaozhuang, Shandong, China
- Fujian Provincial Key Laboratory of Plant Ecophysiology, College of Geographical Sciences, Fujian Normal University, Fuzhou, China
| | - Jinlong Li
- Key Laboratory of Humid Subtropical Eco-Geographical Process (Ministry of Education), College of Geographical Sciences, Fujian Normal University, Fuzhou, China
- Fujian Provincial Key Laboratory of Plant Ecophysiology, College of Geographical Sciences, Fujian Normal University, Fuzhou, China
| | - Josep Peñuelas
- Global Ecology Unit, CSIC, CREAF-CSIC-UAB, 08193, Bellaterra, Catalonia, Spain
- CREAF, 08193, Cerdanyola del Vallès, Catalonia, Spain
| | - Xueqin Li
- Key Laboratory of Humid Subtropical Eco-Geographical Process (Ministry of Education), College of Geographical Sciences, Fujian Normal University, Fuzhou, China
- Fujian Provincial Key Laboratory of Plant Ecophysiology, College of Geographical Sciences, Fujian Normal University, Fuzhou, China
| | - Dandan Hu
- Key Laboratory of Humid Subtropical Eco-Geographical Process (Ministry of Education), College of Geographical Sciences, Fujian Normal University, Fuzhou, China
- Fujian Provincial Key Laboratory of Plant Ecophysiology, College of Geographical Sciences, Fujian Normal University, Fuzhou, China
| | - Mantang Wang
- College of Tourism, Resources and Environment, Zaozhuang University, Zaozhuang, Shandong, China
| | - Quanlin Zhong
- Key Laboratory of Humid Subtropical Eco-Geographical Process (Ministry of Education), College of Geographical Sciences, Fujian Normal University, Fuzhou, China
- Fujian Provincial Key Laboratory of Plant Ecophysiology, College of Geographical Sciences, Fujian Normal University, Fuzhou, China
| | - Dongliang Cheng
- Key Laboratory of Humid Subtropical Eco-Geographical Process (Ministry of Education), College of Geographical Sciences, Fujian Normal University, Fuzhou, China.
- Fujian Provincial Key Laboratory of Plant Ecophysiology, College of Geographical Sciences, Fujian Normal University, Fuzhou, China.
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21
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Moran ME, Aparecido LMT, Koepke DF, Cooper HF, Doughty CE, Gehring CA, Throop HL, Whitham TG, Allan GJ, Hultine KR. Limits of thermal and hydrological tolerance in a foundation tree species (Populus fremontii) in the desert southwestern United States. THE NEW PHYTOLOGIST 2023; 240:2298-2311. [PMID: 37680030 DOI: 10.1111/nph.19247] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 08/05/2023] [Indexed: 09/09/2023]
Abstract
Populus fremontii is among the most dominant, and ecologically important riparian tree species in the western United States and can thrive in hyper-arid riparian corridors. Yet, P. fremontii forests have rapidly declined over the last decade, particularly in places where temperatures sometimes exceed 50°C. We evaluated high temperature tolerance of leaf metabolism, leaf thermoregulation, and leaf hydraulic function in eight P. fremontii populations spanning a 5.3°C mean annual temperature gradient in a well-watered common garden, and at source locations throughout the lower Colorado River Basin. Two major results emerged. First, despite having an exceptionally high Tcrit (the temperature at which Photosystem II is disrupted) relative to other tree taxa, recent heat waves exceeded Tcrit , requiring evaporative leaf cooling to maintain leaf-to-air thermal safety margins. Second, in midsummer, genotypes from the warmest locations maintained lower midday leaf temperatures, a higher midday stomatal conductance, and maintained turgor pressure at lower water potentials than genotypes from more temperate locations. Taken together, results suggest that under well-watered conditions, P. fremontii can regulate leaf temperature below Tcrit along the warm edge of its distribution. Nevertheless, reduced Colorado River flows threaten to lower water tables below levels needed for evaporative cooling during episodic heat waves.
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Affiliation(s)
- Madeline E Moran
- School of Life Sciences, Arizona State University, Tempe, AZ, 85287, USA
| | - Luiza M T Aparecido
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ, 85287, USA
| | - Dan F Koepke
- Department of Research, Conservation and Collections, Desert Botanical Garden, Phoenix, AZ, 85008, USA
| | - Hillary F Cooper
- Department of Biological Sciences and Center for Adaptable Western Landscapes, Northern Arizona University, Flagstaff, AZ, 86011, USA
| | - Christopher E Doughty
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ, 86011, USA
| | - Catherine A Gehring
- Department of Biological Sciences and Center for Adaptable Western Landscapes, Northern Arizona University, Flagstaff, AZ, 86011, USA
| | - Heather L Throop
- School of Life Sciences, Arizona State University, Tempe, AZ, 85287, USA
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ, 85287, USA
| | - Thomas G Whitham
- Department of Biological Sciences and Center for Adaptable Western Landscapes, Northern Arizona University, Flagstaff, AZ, 86011, USA
| | - Gerard J Allan
- Department of Biological Sciences and Center for Adaptable Western Landscapes, Northern Arizona University, Flagstaff, AZ, 86011, USA
| | - Kevin R Hultine
- Department of Research, Conservation and Collections, Desert Botanical Garden, Phoenix, AZ, 85008, USA
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22
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Gauthey A, Bachofen C, Deluigi J, Didion-Gency M, D'Odorico P, Gisler J, Mas E, Schaub M, Schuler P, Still CJ, Tunas A, Grossiord C. Absence of canopy temperature variation despite stomatal adjustment in Pinus sylvestris under multidecadal soil moisture manipulation. THE NEW PHYTOLOGIST 2023; 240:127-137. [PMID: 37483100 DOI: 10.1111/nph.19136] [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: 04/20/2023] [Accepted: 06/23/2023] [Indexed: 07/25/2023]
Abstract
Global warming and droughts push forests closer to their thermal limits, altering tree carbon uptake and growth. To prevent critical overheating, trees can adjust their thermotolerance (Tcrit ), temperature and photosynthetic optima (Topt and Aopt ), and canopy temperature (Tcan ) to stay below damaging thresholds. However, we lack an understanding of how soil droughts affect photosynthetic thermal plasticity and Tcan regulation. In this study, we measured the effect of soil moisture on the seasonal and diurnal dynamics of net photosynthesis (A), stomatal conductance (gs ), and Tcan , as well as the thermal plasticity of photosynthesis (Tcrit , Topt , and Aopt ), over the course of 1 yr using a long-term irrigation experiment in a drought-prone Pinus sylvestris forest in Switzerland. Irrigation resulted in higher needle-level A, gs , Topt , and Aopt compared with naturally drought-exposed trees. No daily or seasonal differences in Tcan were observed between treatments. Trees operated below their thermal thresholds (Tcrit ), independently of soil moisture content. Despite strong Tcan and Tair coupling, we provide evidence that drought reduces trees' temperature optimum due to a substantial reduction of gs during warm and dry periods of the year. These findings provide important insights regarding the effects of soil drought on the thermal tolerance of P. sylvestris.
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Affiliation(s)
- Alice Gauthey
- Plant Ecology Research Laboratory PERL, School of Architecture, Civil and Environmental Engineering, EPFL, Lausanne, CH-1015, Switzerland
- Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, CH-8903, Switzerland
| | - Christoph Bachofen
- Plant Ecology Research Laboratory PERL, School of Architecture, Civil and Environmental Engineering, EPFL, Lausanne, CH-1015, Switzerland
- Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, CH-8903, Switzerland
| | - Janisse Deluigi
- Plant Ecology Research Laboratory PERL, School of Architecture, Civil and Environmental Engineering, EPFL, Lausanne, CH-1015, Switzerland
- Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, CH-8903, Switzerland
| | - Margaux Didion-Gency
- Forest Dynamics Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, CH-8903, Switzerland
| | - Petra D'Odorico
- Land Change Science Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, CH-8903, Switzerland
| | - Jonas Gisler
- Forest Dynamics Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, CH-8903, Switzerland
| | - Eugénie Mas
- Plant Ecology Research Laboratory PERL, School of Architecture, Civil and Environmental Engineering, EPFL, Lausanne, CH-1015, Switzerland
- Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, CH-8903, Switzerland
| | - Marcus Schaub
- Forest Dynamics Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, CH-8903, Switzerland
| | - Philipp Schuler
- Forest Dynamics Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, CH-8903, Switzerland
| | - Christopher J Still
- Forest Ecosystems and Society, Oregon State University, Corvallis, 97331, OR, USA
| | - Alex Tunas
- Plant Ecology Research Laboratory PERL, School of Architecture, Civil and Environmental Engineering, EPFL, Lausanne, CH-1015, Switzerland
- Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, CH-8903, Switzerland
| | - Charlotte Grossiord
- Plant Ecology Research Laboratory PERL, School of Architecture, Civil and Environmental Engineering, EPFL, Lausanne, CH-1015, Switzerland
- Community Ecology Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, CH-8903, Switzerland
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23
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Doughty CE, Keany JM, Wiebe BC, Rey-Sanchez C, Carter KR, Middleby KB, Cheesman AW, Goulden ML, da Rocha HR, Miller SD, Malhi Y, Fauset S, Gloor E, Slot M, Oliveras Menor I, Crous KY, Goldsmith GR, Fisher JB. Tropical forests are approaching critical temperature thresholds. Nature 2023; 621:105-111. [PMID: 37612501 DOI: 10.1038/s41586-023-06391-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 06/30/2023] [Indexed: 08/25/2023]
Abstract
The critical temperature beyond which photosynthetic machinery in tropical trees begins to fail averages approximately 46.7 °C (Tcrit)1. However, it remains unclear whether leaf temperatures experienced by tropical vegetation approach this threshold or soon will under climate change. Here we found that pantropical canopy temperatures independently triangulated from individual leaf thermocouples, pyrgeometers and remote sensing (ECOSTRESS) have midday peak temperatures of approximately 34 °C during dry periods, with a long high-temperature tail that can exceed 40 °C. Leaf thermocouple data from multiple sites across the tropics suggest that even within pixels of moderate temperatures, upper canopy leaves exceed Tcrit 0.01% of the time. Furthermore, upper canopy leaf warming experiments (+2, 3 and 4 °C in Brazil, Puerto Rico and Australia, respectively) increased leaf temperatures non-linearly, with peak leaf temperatures exceeding Tcrit 1.3% of the time (11% for more than 43.5 °C, and 0.3% for more than 49.9 °C). Using an empirical model incorporating these dynamics (validated with warming experiment data), we found that tropical forests can withstand up to a 3.9 ± 0.5 °C increase in air temperatures before a potential tipping point in metabolic function, but remaining uncertainty in the plasticity and range of Tcrit in tropical trees and the effect of leaf death on tree death could drastically change this prediction. The 4.0 °C estimate is within the 'worst-case scenario' (representative concentration pathway (RCP) 8.5) of climate change predictions2 for tropical forests and therefore it is still within our power to decide (for example, by not taking the RCP 6.0 or 8.5 route) the fate of these critical realms of carbon, water and biodiversity3,4.
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Affiliation(s)
- Christopher E Doughty
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ, USA.
| | - Jenna M Keany
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ, USA
| | - Benjamin C Wiebe
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ, USA
| | - Camilo Rey-Sanchez
- Department of Marine, Earth and Atmospheric Sciences, North Carolina State University, Raleigh, NC, USA
| | - Kelsey R Carter
- College of Forest Resources and Environmental Sciences, Michigan Technological University, Houghton, MI, USA
- Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Kali B Middleby
- Centre for Tropical Environmental and Sustainability Science, James Cook University, Cairns, Queensland, Australia
| | - Alexander W Cheesman
- Centre for Tropical Environmental and Sustainability Science, James Cook University, Cairns, Queensland, Australia
| | - Michael L Goulden
- Department of Earth System Science, University of California, Irvine, CA, USA
| | - Humberto R da Rocha
- Departamento de Ciencias Atmosfericas, Universidade de São Paulo, São Paulo, Brazil
| | - Scott D Miller
- Atmospheric Sciences Research Center, State University of New York at Albany, Albany, NY, USA
| | - Yadvinder Malhi
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, UK
| | - Sophie Fauset
- School of Geography, Earth and Environmental Sciences, University of Plymouth, Plymouth, UK
| | | | - Martijn Slot
- Smithsonian Tropical Research Institute, Balboa, Ancon, Republic of Panama
| | - 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
| | - Kristine Y Crous
- Western Sydney University, Hawkesbury Institute for the Environment, Penrith, New South Wales, Australia
| | - Gregory R Goldsmith
- Schmid College of Science and Technology, Chapman University, Orange, CA, USA
| | - Joshua B Fisher
- Schmid College of Science and Technology, Chapman University, Orange, CA, USA
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24
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Crous KY, Cheesman AW, Middleby K, Rogers EIE, Wujeska-Klause A, Bouet AYM, Ellsworth DS, Liddell MJ, Cernusak LA, Barton CVM. Similar patterns of leaf temperatures and thermal acclimation to warming in temperate and tropical tree canopies. TREE PHYSIOLOGY 2023; 43:1383-1399. [PMID: 37099805 PMCID: PMC10423462 DOI: 10.1093/treephys/tpad054] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 03/22/2023] [Accepted: 04/17/2023] [Indexed: 06/19/2023]
Abstract
As the global climate warms, a key question is how increased leaf temperatures will affect tree physiology and the coupling between leaf and air temperatures in forests. To explore the impact of increasing temperatures on plant performance in open air, we warmed leaves in the canopy of two mature evergreen forests, a temperate Eucalyptus woodland and a tropical rainforest. The leaf heaters consistently maintained leaves at a target of 4 °C above ambient leaf temperatures. Ambient leaf temperatures (Tleaf) were mostly coupled to air temperatures (Tair), but at times, leaves could be 8-10 °C warmer than ambient air temperatures, especially in full sun. At both sites, Tleaf was warmer at higher air temperatures (Tair > 25 °C), but was cooler at lower Tair, contrary to the 'leaf homeothermy hypothesis'. Warmed leaves showed significantly lower stomatal conductance (-0.05 mol m-2 s-1 or -43% across species) and net photosynthesis (-3.91 μmol m-2 s-1 or -39%), with similar rates in leaf respiration rates at a common temperature (no acclimation). Increased canopy leaf temperatures due to future warming could reduce carbon assimilation via reduced photosynthesis in these forests, potentially weakening the land carbon sink in tropical and temperate forests.
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Affiliation(s)
- K Y Crous
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, New South Wales 2751, Australia
| | - A W Cheesman
- Centre for Tropical Environmental and Sustainability Science (TESS) and College of Science and Engineering, James Cook University, Cairns, Queensland 4878, Australia
| | - K Middleby
- Centre for Tropical Environmental and Sustainability Science (TESS) and College of Science and Engineering, James Cook University, Cairns, Queensland 4878, Australia
| | - E I E Rogers
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, New South Wales 2751, Australia
| | - A Wujeska-Klause
- Urban Studies, School of Social Science, Western Sydney University, Penrith, New South Wales 2751, Australia
| | - A Y M Bouet
- Centre for Tropical Environmental and Sustainability Science (TESS) and College of Science and Engineering, James Cook University, Cairns, Queensland 4878, Australia
| | - D S Ellsworth
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, New South Wales 2751, Australia
| | - M J Liddell
- Centre for Tropical Environmental and Sustainability Science (TESS) and College of Science and Engineering, James Cook University, Cairns, Queensland 4878, Australia
| | - L A Cernusak
- Centre for Tropical Environmental and Sustainability Science (TESS) and College of Science and Engineering, James Cook University, Cairns, Queensland 4878, Australia
| | - C V M Barton
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, New South Wales 2751, Australia
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25
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Cox AJF, Hartley IP, Meir P, Sitch S, Dusenge ME, Restrepo Z, González-Caro S, Villegas JC, Uddling J, Mercado LM. Acclimation of photosynthetic capacity and foliar respiration in Andean tree species to temperature change. THE NEW PHYTOLOGIST 2023; 238:2329-2344. [PMID: 36987979 DOI: 10.1111/nph.18900] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 03/13/2023] [Indexed: 05/19/2023]
Abstract
Climate warming is causing compositional changes in Andean tropical montane forests (TMFs). These shifts are hypothesised to result from differential responses to warming of cold- and warm-affiliated species, with the former experiencing mortality and the latter migrating upslope. The thermal acclimation potential of Andean TMFs remains unknown. Along a 2000 m Andean altitudinal gradient, we planted individuals of cold- and warm-affiliated species (under common soil and irrigation), exposing them to the hot and cold extremes of their thermal niches, respectively. We measured the response of net photosynthesis (Anet ), photosynthetic capacity and leaf dark respiration (Rdark ) to warming/cooling, 5 months after planting. In all species, Anet and photosynthetic capacity at 25°C were highest when growing at growth temperatures (Tg ) closest to their thermal means, declining with warming and cooling in cold-affiliated and warm-affiliated species, respectively. When expressed at Tg , photosynthetic capacity and Rdark remained unchanged in cold-affiliated species, but the latter decreased in warm-affiliated counterparts. Rdark at 25°C increased with temperature in all species, but remained unchanged when expressed at Tg . Both species groups acclimated to temperature, but only warm-affiliated species decreased Rdark to photosynthetic capacity ratio at Tg as temperature increased. This could confer them a competitive advantage under future warming.
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Affiliation(s)
- Andrew J F Cox
- Geography, Faculty of Environment, Science and Economy, University of Exeter, Exeter, EX4 4RKJ, UK
| | - Iain P Hartley
- Geography, Faculty of Environment, Science and Economy, University of Exeter, Exeter, EX4 4RKJ, UK
| | - Patrick Meir
- School of Geosciences, University of Edinburgh, Edinburgh, EH9 3JN, UK
- Division of Plant Sciences, Research School of Biology, The Australian National University, Canberra, ACT, 2601, Australia
| | - Stephen Sitch
- Geography, Faculty of Environment, Science and Economy, University of Exeter, Exeter, EX4 4RKJ, UK
| | - Mirindi Eric Dusenge
- Geography, Faculty of Environment, Science and Economy, University of Exeter, Exeter, EX4 4RKJ, UK
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, Gothenburg, SE-405 30, Sweden
- Department of Biology, The University of Western Ontario, London, ON, N6A 3K7, Canada
| | - Zorayda Restrepo
- Grupo de Investigación en Ecología Aplicada, Universidad de Antioquia, Medellín, Colombia
- UK Centre for Ecology and Hydrology, Crowmarsh-Gifford, Wallingford, OX10 8BB, UK
| | - Sebastian González-Caro
- Geography, Faculty of Environment, Science and Economy, University of Exeter, Exeter, EX4 4RKJ, UK
- UK Centre for Ecology and Hydrology, Crowmarsh-Gifford, Wallingford, OX10 8BB, UK
| | - Juan Camilo Villegas
- Grupo de Investigación en Ecología Aplicada, Universidad de Antioquia, Medellín, Colombia
| | - Johan Uddling
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, Gothenburg, SE-405 30, Sweden
| | - Lina M Mercado
- Geography, Faculty of Environment, Science and Economy, University of Exeter, Exeter, EX4 4RKJ, UK
- UK Centre for Ecology and Hydrology, Crowmarsh-Gifford, Wallingford, OX10 8BB, UK
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26
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Guo Z, Still CJ, Lee CKF, Ryu Y, Blonder B, Wang J, Bonebrake TC, Hughes A, Li Y, Yeung HCH, Zhang K, Law YK, Lin Z, Wu J. Does plant ecosystem thermoregulation occur? An extratropical assessment at different spatial and temporal scales. THE NEW PHYTOLOGIST 2023; 238:1004-1018. [PMID: 36495263 DOI: 10.1111/nph.18632] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 11/11/2022] [Indexed: 06/17/2023]
Abstract
To what degree plant ecosystems thermoregulate their canopy temperature (Tc ) is critical to assess ecosystems' metabolisms and resilience with climate change, but remains controversial, with opinions from no to moderate thermoregulation capability. With global datasets of Tc , air temperature (Ta ), and other environmental and biotic variables from FLUXNET and satellites, we tested the 'limited homeothermy' hypothesis (indicated by Tc & Ta regression slope < 1 or Tc < Ta around midday) across global extratropics, including temporal and spatial dimensions. Across daily to weekly and monthly timescales, over 80% of sites/ecosystems have slopes ≥1 or Tc > Ta around midday, rejecting the above hypothesis. For those sites unsupporting the hypothesis, their Tc -Ta difference (ΔT) exhibits considerable seasonality that shows negative, partial correlations with leaf area index, implying a certain degree of thermoregulation capability. Spatially, site-mean ΔT exhibits larger variations than the slope indicator, suggesting ΔT is a more sensitive indicator for detecting thermoregulatory differences across biomes. Furthermore, this large spatial-wide ΔT variation (0-6°C) is primarily explained by environmental variables (38%) and secondarily by biotic factors (15%). These results demonstrate diverse thermoregulation patterns across global extratropics, with most ecosystems negating the 'limited homeothermy' hypothesis, but their thermoregulation still occurs, implying that slope < 1 or Tc < Ta are not necessary conditions for plant thermoregulation.
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Affiliation(s)
- Zhengfei Guo
- School for Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Christopher J Still
- Forest Ecosystems and Society, Oregon State University, Corvallis, OR, 97331, USA
| | - Calvin K F Lee
- School for Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Youngryel Ryu
- Department of Landscape Architecture and Rural Systems Engineering, College of Agriculture and Life Sciences, Seoul National University, Gwanak-gu, Seoul, South Korea
| | - Benjamin Blonder
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA, 94720, USA
| | - Jing Wang
- School for Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Timothy C Bonebrake
- School for Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, China
- Institute for Climate and Carbon Neutrality, The University of Hong Kong, Hong Kong, China
| | - Alice Hughes
- School for Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, China
- Institute for Climate and Carbon Neutrality, The University of Hong Kong, Hong Kong, China
| | - Yan Li
- State Key Laboratory of Earth Surface Processes and Resources Ecology, Beijing Normal University, Beijing, 100875, China
| | - Henry C H Yeung
- School for Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Kun Zhang
- School for Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, China
- Department of Mathematics, The University of Hong Kong, Hong Kong, China
| | - Ying Ki Law
- School for Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Ziyu Lin
- School for Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Jin Wu
- School for Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, China
- Institute for Climate and Carbon Neutrality, The University of Hong Kong, Hong Kong, China
- State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong, China
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27
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Vinod N, Slot M, McGregor IR, Ordway EM, Smith MN, Taylor TC, Sack L, Buckley TN, Anderson-Teixeira KJ. Thermal sensitivity across forest vertical profiles: patterns, mechanisms, and ecological implications. THE NEW PHYTOLOGIST 2023; 237:22-47. [PMID: 36239086 DOI: 10.1111/nph.18539] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Accepted: 07/31/2022] [Indexed: 06/16/2023]
Abstract
Rising temperatures are influencing forests on many scales, with potentially strong variation vertically across forest strata. Using published research and new analyses, we evaluate how microclimate and leaf temperatures, traits, and gas exchange vary vertically in forests, shaping tree, and ecosystem ecology. In closed-canopy forests, upper canopy leaves are exposed to the highest solar radiation and evaporative demand, which can elevate leaf temperature (Tleaf ), particularly when transpirational cooling is curtailed by limited stomatal conductance. However, foliar traits also vary across height or light gradients, partially mitigating and protecting against the elevation of upper canopy Tleaf . Leaf metabolism generally increases with height across the vertical gradient, yet differences in thermal sensitivity across the gradient appear modest. Scaling from leaves to trees, canopy trees have higher absolute metabolic capacity and growth, yet are more vulnerable to drought and damaging Tleaf than their smaller counterparts, particularly under climate change. By contrast, understory trees experience fewer extreme high Tleaf 's but have fewer cooling mechanisms and thus may be strongly impacted by warming under some conditions, particularly when exposed to a harsher microenvironment through canopy disturbance. As the climate changes, integrating the patterns and mechanisms reviewed here into models will be critical to forecasting forest-climate feedback.
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Affiliation(s)
- Nidhi Vinod
- Conservation Ecology Center, Smithsonian's National Zoo & Conservation Biology Institute, Front Royal, VA, 22630, USA
- Department of Ecology and Evolutionary Biology, UCLA, Los Angeles, CA, 90039, USA
| | - Martijn Slot
- Smithsonian Tropical Research Institute, Apartado Postal 0843-03092, Panama City, Panama
| | - Ian R McGregor
- Center for Geospatial Analytics, North Carolina State University, Raleigh, NC, 27607, USA
| | - Elsa M Ordway
- Department of Ecology and Evolutionary Biology, UCLA, Los Angeles, CA, 90039, USA
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Marielle N Smith
- Department of Forestry, Michigan State University, East Lansing, MI, 48824, USA
- School of Natural Sciences, College of Environmental Sciences and Engineering, Bangor University, Bangor, LL57 2DG, UK
| | - Tyeen C Taylor
- Department of Civil & Environmental Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Lawren Sack
- Department of Ecology and Evolutionary Biology, UCLA, Los Angeles, CA, 90039, USA
| | - Thomas N Buckley
- Department of Plant Sciences, University of California, Davis, CA, 95616, USA
| | - Kristina J Anderson-Teixeira
- Conservation Ecology Center, Smithsonian's National Zoo & Conservation Biology Institute, Front Royal, VA, 22630, USA
- Smithsonian Tropical Research Institute, Apartado Postal 0843-03092, Panama City, Panama
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28
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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: 2.5] [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.
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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
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29
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Tree species matter for forest microclimate regulation during the drought year 2018: disentangling environmental drivers and biotic drivers. Sci Rep 2022; 12:17559. [PMID: 36266469 PMCID: PMC9584904 DOI: 10.1038/s41598-022-22582-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 10/17/2022] [Indexed: 01/13/2023] Open
Abstract
Tree canopies are considered to effectively buffer climate extremes and to mitigate climate change effects. Droughts, which are predicted to become more frequent in the course of climate change, might alter the microclimatic cooling potential of trees. However, our understanding of how microclimate at the tree canopy level is modulated by environmental and tree characteristics and their interactions is still limited. Here, we investigated canopy temperature regulation for five mature co-occurring tree species for two contrasting hydrological situations during the severe drought in 2018. Even though we observed a significant drought-induced decline in canopy cover and transpiration across tree species, we found evidence that differences in the water use strategies of trees affected cooling mechanisms differently. Although a large share of the variations in the cooling potential of trees was explained by direct and indirect effects of meteorological factors, we identified a gradual shift in importance from latent heat flux to components defining the magnitude of sensible heat flux on the energy budget of tree as the drought gained severity. The decrease in latent heat fluxes, approximated by sap flow rates, furthermore resulted in a reduced cooling potential and an equalization of tree species canopy temperatures.
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30
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Li X, Wen Y, Chen X, Qie Y, Cao KF, Wee AKS. Correlations between photosynthetic heat tolerance and leaf anatomy and climatic niche in Asian mangrove trees. PLANT BIOLOGY (STUTTGART, GERMANY) 2022; 24:960-966. [PMID: 35962602 DOI: 10.1111/plb.13460] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 07/18/2022] [Indexed: 06/15/2023]
Abstract
Photosynthetic heat tolerance (PHT ) is a key predictor of plant response to climate change. Mangroves are an ecologically and economically important coastal plant community comprised of trees growing at their physiological limits. Mangroves are currently impacted by global warming, yet the PHT of mangrove trees is poorly understood. In this study, we provide the first assessment of PHT in 13 Asian mangrove species, based on the critical temperature that causes the initial damage (TCrit ) and the temperature that causes 50% damage (T50 ) to photosystem II. We tested the hypotheses that the PHT in mangroves is: (i) correlated with climatic niche and leaf traits, and (ii) higher than in plants from other tropical ecosystems. Our results demonstrated correlations between PHT and multiple key climate variables, the palisade to spongy mesophyll ratio and the leaf area. The two most heat-sensitive species were Kandelia obovata and Avicennia marina. Our study also revealed that mangrove trees show high heat tolerance compared to plants from other tropical ecosystems. The high PHT of mangroves thus demonstrated a conservative evolutionary strategy in heat tolerance, and highlights the need for integrative and comparative studies on thermoregulatory traits and climatic niche in order to understand the physiological response of mangrove trees to climate change-driven heatwaves and rising global temperatures.
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Affiliation(s)
- X Li
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, Guangxi, China
| | - Y Wen
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - X Chen
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, Guangxi, China
| | - Y Qie
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, Guangxi, China
| | - K-F Cao
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, Guangxi, China
| | - A K S Wee
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, Guangxi, China
- School of Environmental and Geographical Sciences, University of Nottingham Malaysia, Jalan Broga, Semenyih, Malaysia
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31
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No evidence of canopy-scale leaf thermoregulation to cool leaves below air temperature across a range of forest ecosystems. Proc Natl Acad Sci U S A 2022; 119:e2205682119. [PMID: 36095211 PMCID: PMC9499539 DOI: 10.1073/pnas.2205682119] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Understanding and predicting the relationship between leaf temperature (Tleaf) and air temperature (Tair) is essential for projecting responses to a warming climate, as studies suggest that many forests are near thermal thresholds for carbon uptake. Based on leaf measurements, the limited leaf homeothermy hypothesis argues that daytime Tleaf is maintained near photosynthetic temperature optima and below damaging temperature thresholds. Specifically, leaves should cool below Tair at higher temperatures (i.e., > ∼25-30°C) leading to slopes <1 in Tleaf/Tair relationships and substantial carbon uptake when leaves are cooler than air. This hypothesis implies that climate warming will be mitigated by a compensatory leaf cooling response. A key uncertainty is understanding whether such thermoregulatory behavior occurs in natural forest canopies. We present an unprecedented set of growing season canopy-level leaf temperature (Tcan) data measured with thermal imaging at multiple well-instrumented forest sites in North and Central America. Our data do not support the limited homeothermy hypothesis: canopy leaves are warmer than air during most of the day and only cool below air in mid to late afternoon, leading to Tcan/Tair slopes >1 and hysteretic behavior. We find that the majority of ecosystem photosynthesis occurs when canopy leaves are warmer than air. Using energy balance and physiological modeling, we show that key leaf traits influence leaf-air coupling and ultimately the Tcan/Tair relationship. Canopy structure also plays an important role in Tcan dynamics. Future climate warming is likely to lead to even greater Tcan, with attendant impacts on forest carbon cycling and mortality risk.
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32
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Carter KR, Dickman LT. Recovery of seedling carbon balance despite hydraulic impairment following hot drought. TREE PHYSIOLOGY 2022; 42:1527-1531. [PMID: 35445728 DOI: 10.1093/treephys/tpac045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 04/04/2022] [Indexed: 06/14/2023]
Affiliation(s)
- Kelsey R Carter
- Earth and Environmental Science Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - L Turin Dickman
- Earth and Environmental Science Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
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33
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Brienen R, Helle G, Pons T, Boom A, Gloor M, Groenendijk P, Clerici S, Leng M, Jones C. Paired analysis of tree ring width and carbon isotopes indicates when controls on tropical tree growth change from light to water limitations. TREE PHYSIOLOGY 2022; 42:1131-1148. [PMID: 34718816 PMCID: PMC9190751 DOI: 10.1093/treephys/tpab142] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 10/22/2021] [Indexed: 06/13/2023]
Abstract
Light and water availability are likely to vary over the lifespan of closed-canopy forest trees, with understory trees experiencing greater limitations to growth by light and canopy trees greater limitation due to drought. As drought and shade have opposing effects on isotope discrimination (Δ13C), paired measurement of ring width and Δ13C can potentially be used to differentiate between water and light limitations on tree growth. We tested this approach for Cedrela trees from three tropical forests in Bolivia and Mexico that differ in rainfall and canopy structure. Using lifetime ring width and Δ13C data for trees of up to and over 200 years old, we assessed how controls on tree growth changed from understory to the canopy. Growth and Δ13C are mostly anti-correlated in the understory, but this anti-correlation disappeared or weakened when trees reached the canopy, especially at the wettest site. This indicates that understory growth variation is controlled by photosynthetic carbon assimilation due to variation in light levels. Once trees reached the canopy, inter-annual variation in growth and Δ13C at one of the dry sites showed positive correlations, indicating that inter-annual variation in growth is driven by variation in water stress affecting stomatal conductance. Paired analysis of ring widths and carbon isotopes provides significant insight in what environmental factors control growth over a tree's life; strong light limitations for understory trees in closed-canopy moist forests switched to drought stress for (sub)canopy trees in dry forests. We show that combined isotope and ring width measurements can significantly improve our insights in tree functioning and be used to disentangle limitations due to shade from those due to drought.
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Affiliation(s)
| | - Gerhard Helle
- GFZ—German Research Centre for Geosciences, Section 4.3 Climate Dynamics and Landscape Evolution, 14473 Potsdam, Germany
| | - Thijs Pons
- Plant Ecophysiology, Institute of Environmental Biology, Utrecht University, 3512 Utrecht, The Netherlands
| | - Arnoud Boom
- School of Geography, University of Leicester, Leicester LE1 7RH, UK
| | - Manuel Gloor
- School of Geography, University of Leeds, Leeds LS2 9JT, UK
| | - Peter Groenendijk
- Department of Plant Biology, Institute of Biology, PO Box: 6109, University of Campinas, UNICAMP, Campinas 13083-970, Brazil
- Ecology and Biodiversity, Institute of Environmental Biology, Utrecht University, 3584 Utrecht, The Netherlands
| | | | - Melanie Leng
- National Environmental Isotope Facility, British Geological Survey, Nottingham NG12 5GG, UK
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34
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Blasini DE, Koepke DF, Bush SE, Allan GJ, Gehring CA, Whitham TG, Day TA, Hultine KR. Tradeoffs between leaf cooling and hydraulic safety in a dominant arid land riparian tree species. PLANT, CELL & ENVIRONMENT 2022; 45:1664-1681. [PMID: 35147232 DOI: 10.1111/pce.14292] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 02/07/2022] [Indexed: 06/14/2023]
Abstract
Leaf carbon gain optimization in hot environments requires balancing leaf thermoregulation with avoiding excessive water loss via transpiration and hydraulic failure. The tradeoffs between leaf thermoregulation and transpirational water loss can determine the ecological consequences of heat waves that are increasing in frequency and intensity. We evaluated leaf thermoregulation strategies in warm- (>40°C maximum summer temperature) and cool-adapted (<40°C maximum summer temperature) genotypes of the foundation tree species, Populus fremontii, using a common garden near the mid-elevational point of its distribution. We measured leaf temperatures and assessed three modes of leaf thermoregulation: leaf morphology, midday canopy stomatal conductance and stomatal sensitivity to vapour pressure deficit. Data were used to parameterize a leaf energy balance model to estimate contrasts in midday leaf temperature in warm- and cool-adapted genotypes. Warm-adapted genotypes had 39% smaller leaves and 38% higher midday stomatal conductance, reflecting a 3.8°C cooler mean leaf temperature than cool-adapted genotypes. Leaf temperatures modelled over the warmest months were on average 1.1°C cooler in warm- relative to cool-adapted genotypes. Results show that plants adapted to warm environments are predisposed to tightly regulate leaf temperatures during heat waves, potentially at an increased risk of hydraulic failure.
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Affiliation(s)
- Davis E Blasini
- School of Life Sciences, Arizona State University, Tempe, Arizona, USA
| | - Dan F Koepke
- Department of Research, Conservation and Collections, Desert Botanical Garden, Phoenix, Arizona, USA
| | - Susan E Bush
- Department of Research, Conservation and Collections, Desert Botanical Garden, Phoenix, Arizona, USA
| | - Gerard J Allan
- Center for Adaptable Western Landscapes, Northern Arizona University, Flagstaff, Arizona, USA
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, USA
| | - Catherine A Gehring
- Center for Adaptable Western Landscapes, Northern Arizona University, Flagstaff, Arizona, USA
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, USA
| | - Thomas G Whitham
- Center for Adaptable Western Landscapes, Northern Arizona University, Flagstaff, Arizona, USA
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, USA
| | - Thomas A Day
- School of Life Sciences, Arizona State University, Tempe, Arizona, USA
| | - Kevin R Hultine
- Department of Research, Conservation and Collections, Desert Botanical Garden, Phoenix, Arizona, USA
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35
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Bartholomew DC, Banin LF, Bittencourt PRL, Suis MAF, Mercado LM, Nilus R, Burslem DFRP, Rowland LR. Differential nutrient limitation and tree height control leaf physiology, supporting niche partitioning in tropical dipterocarp forests. Funct Ecol 2022. [DOI: 10.1111/1365-2435.14094] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- D. C. Bartholomew
- College of Life and Environmental Sciences University of Exeter Exeter UK
- Department of Ecology and Environmental Science Umeå University Umeå Sweden
| | - L. F. Banin
- UK Centre for Ecology & Hydrology, Penicuik Midlothian UK
| | | | - M. A. F. Suis
- Forest Research Centre, Sabah Forestry Department, P.O. Box 1407, 90715 Sandakan Sabah Malaysia
| | - L. M. Mercado
- College of Life and Environmental Sciences University of Exeter Exeter UK
- UK Centre for Ecology & Hydrology Wallingford UK
| | - R. Nilus
- Forest Research Centre, Sabah Forestry Department, P.O. Box 1407, 90715 Sandakan Sabah Malaysia
| | | | - L. R. Rowland
- College of Life and Environmental Sciences University of Exeter Exeter UK
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36
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Peng G, Xiong Y, Yin M, Wang X, Zhou W, Cheng Z, Zhang YJ, Yang D. Leaf Venation Architecture in Relation to Leaf Size Across Leaf Habits and Vein Types in Subtropical Woody Plants. FRONTIERS IN PLANT SCIENCE 2022; 13:873036. [PMID: 35599892 PMCID: PMC9121095 DOI: 10.3389/fpls.2022.873036] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 03/21/2022] [Indexed: 05/12/2023]
Abstract
Leaves are enormously diverse in their size and venation architecture, both of which are core determinants of plant adaptation to environments. Leaf size is an important determinant of leaf function and ecological strategy, while leaf venation, the main structure for support and transport, determines the growth, development, and performance of a leaf. The scaling relationship between venation architecture and leaf size has been explored, but the relationship within a community and its potential variations among species with different vein types and leaf habits have not been investigated. Here, we measured vein traits and leaf size across 39 broad-leaved woody species within a subtropical forest community in China and analyzed the scaling relationship using ordinary least squares and standard major axis method. Then, we compared our results with the global dataset. The major vein density, and the ratio of major (1° and 2°) to minor (3° and higher) vein density both geometrically declined with leaf size across different vein types and leaf habits. Further, palmate-veined species have higher major vein density and a higher ratio of major to minor vein density at the given leaf size than pinnate-veined species, while evergreen and deciduous species showed no difference. These robust trends were confirmed by reanalyzing the global dataset using the same major vein classification as ours. We also found a tradeoff between the cell wall mass per vein length of the major vein and the major vein density. These vein scaling relationships have important implications on the optimization of leaf size, niche differentiation of coexisting species, plant drought tolerance, and species distribution.
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Affiliation(s)
- Guoquan Peng
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, China
| | - Yingjie Xiong
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, China
| | - Mengqi Yin
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, China
| | - Xiaolin Wang
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, China
| | - Wei Zhou
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, China
| | - Zhenfeng Cheng
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, China
| | - Yong-Jiang Zhang
- School of Biology and Ecology, University of Maine, Orono, ME, United States
| | - Dongmei Yang
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, China
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37
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Zhao F, Yang T, Luo C, Rao W, Yang G, Li G, Shen Z. Comparing Elevational Patterns of Taxonomic, Phylogenetic, and Functional Diversity of Woody Plants Reveal the Asymmetry of Community Assembly Mechanisms on a Mountain in the Hengduan Mountains Region. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.869258] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The contributions and interaction of biotic and abiotic processes in community assembly are crucial for understanding the elevational patterns of biodiversity. The combined analyses of taxonomic, phylogenetic, and functional diversity are necessary to resolve this issue. By investigating vegetation in 24 transects sampled on Hongla Snow Mountain, in the central Hengduan Mountain Ranges in Southwest China, we delineated the elevational vegetation spectrum on the eastern and western slopes, analyzed the elevational variation in taxonomic, phylogenetic, and functional diversity of woody plant species, and compared the community structure of phylogeny and function in the low-elevational shrublands, mid-elevational forests, and alpine shrubs and meadows. The species richness, phylogenetic diversity, and functional diversity of woody plants showed nonstandard hump-shaped patterns with two peaks along the elevational gradient. The community structure of phylogeny and function (including tree height, leaf area, specific leaf area, leaf thickness, bark thickness, and wood density) clustered in the low-elevation shrub communities, being random and over-dispersed in mid-elevational forests. The phylogenic structure was over-dispersed in alpine communities, whereas the functional structure was clustered. Elevational patterns in taxonomic, phylogenetic, and functional diversity, together with the mean and variation in woody plant functional traits, suggested drought stress and freeze stress as environmental filters dominating the assembly of low and high elevation non-forest communities, and a conspicuous effect of biotic facilitation was also suggested for alpine habitats. By contrast, interspecific competition dominated the community assembly of forests at mid-elevations. The difference in biodiversity indices between the west and east slopes reflected the effects of the Indian Monsoon on the geomorphic patterns of ecosystem structure. These results increased our understanding of biodiversity patterns and underlying mechanisms in the Hengduan Mountains of Southwest China and highlighted the priorities for biodiversity conservation in this region.
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38
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Kitudom N, Fauset S, Zhou Y, Fan Z, Li M, He M, Zhang S, Xu K, Lin H. Thermal safety margins of plant leaves across biomes under a heatwave. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 806:150416. [PMID: 34852425 DOI: 10.1016/j.scitotenv.2021.150416] [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: 07/15/2021] [Revised: 09/13/2021] [Accepted: 09/14/2021] [Indexed: 06/13/2023]
Abstract
Climate change has great impacts on forest ecosystems, especially with the increasing frequency of heatwaves. Thermal safety margin (TSM) calculated by the difference between body temperature and thermotolerance threshold is useful to predict thermal safety of organisms. It has been widely used for animals, whereas has rarely been reported for plants. Besides, most of the previous studies used only thermotolerance to estimate thermal safety or used thermotolerance and air temperature (Ta) to calculate TSM. However, leaf temperature (Tl) is the real "body" temperature of plant leaves. Tl decoupling from Ta might induce large error in TSM. Here, we investigated TSM of photosystem II (thermotolerance of PSII - the maximum Tl) of dominant canopy plants in four forests from tropical to temperate biomes during a heatwave, and compared the TSMs calculated by Tl (TSM.Tl) and Ta (TSM.Ta) respectively. Also, thermal related leaf traits were investigated. The results showed that both TSM. Tl and TSM.Ta decreased from the cool forests to the hot forests. TSM.Tl was highly correlated with the maximum leaf temperature (Tlmax), while had an opposite trend with thermotolerance across biomes. Thus, Tlmax instead of thermotolerance can be used to evaluate TSM. The maximum Ta (Tamax), Tlmax and leaf traits explained 68% of the variance of thermotolerance in a random forest model, where Tamax and Tlmax explained 62%. TSM.Ta could not distinguish thermal safety differences between co-occurring species. The overestimation of TSM by TSM.Ta increased from the tropical to the temperate forest, and increased with Tl within biome. Therefore, it is not recommended to use TSM.Ta in cold forests. The present study enriches the dataset of photosynthetic TSMs across biomes, proposes using Tlmax to estimate TSMs of leaves, and highlights the risk of hot dry forest during heatwaves.
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Affiliation(s)
- Nawatbhrist Kitudom
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Sophie Fauset
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China; School of Geography, Earth and Environmental Sciences, University of Plymouth, Plymouth, UK
| | - Yingying Zhou
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zexin Fan
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China; Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Xishuangbanna 666303, China; Ailaoshan Station of Subtropical Forest Ecosystem Studies, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Jingdong, Yunnan 676209, China
| | - Murong Li
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China; College of Biology and Chemistry, Puer University, Puer, Yunnan 665000, China
| | - Mingjian He
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China; College of Biology and Chemistry, Puer University, Puer, Yunnan 665000, China
| | - Shubin Zhang
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China
| | - Kun Xu
- Yunnan Lijiang Forest Ecosystem National Observation and Research Station, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China
| | - Hua Lin
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China; Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Xishuangbanna 666303, China.
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39
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Warming Responses of Leaf Morphology Are Highly Variable among Tropical Tree Species. FORESTS 2022. [DOI: 10.3390/f13020219] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Leaf morphological traits vary along climate gradients, but it is currently unclear to what extent this results from acclimation rather than adaptation. Knowing so is important for predicting the functioning of long-lived organisms, such as trees, in a rapidly changing climate. We investigated the leaf morphological warming responses of 18 tropical tree species with early (ES) abd late (LS) successional strategies, planted at three sites along an elevation gradient from 2400 m a.s.l. (15.2 °C mean temperature) to 1300 m a.s.l. (20.6 °C mean temperature) in Rwanda. Leaf size expressed as leaf area (LA) and leaf mass per area (LMA) decreased, while leaf width-to-length ratio (W/L) increased with warming, but only for one third to half of the species. While LA decreased in ES species, but mostly not in LS species, changes in LMA and leaf W/L were common in both successional groups. ES species had lower LMA and higher LA and leaf W/L compared to LS species. Values of LMA and LA of juvenile trees in this study were mostly similar to corresponding data on four mature tree species in another elevation-gradient study in Rwanda, indicating that our results are applicable also to mature forest trees. We conclude that leaf morphological responses to warming differ greatly between both successional groups and individual species, with potential consequences for species competitiveness and community composition in a warmer climate.
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Tarvainen L, Wittemann M, Mujawamariya M, Manishimwe A, Zibera E, Ntirugulirwa B, Ract C, Manzi OJL, Andersson MX, Spetea C, Nsabimana D, Wallin G, Uddling J. Handling the heat - photosynthetic thermal stress in tropical trees. THE NEW PHYTOLOGIST 2022; 233:236-250. [PMID: 34655491 DOI: 10.1111/nph.17809] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 10/09/2021] [Indexed: 06/13/2023]
Abstract
Warming climate increases the risk for harmful leaf temperatures in terrestrial plants, causing heat stress and loss of productivity. The heat sensitivity may be particularly high in equatorial tropical tree species adapted to a thermally stable climate. Thermal thresholds of the photosynthetic system of sun-exposed leaves were investigated in three tropical montane tree species native to Rwanda with different growth and water use strategies (Harungana montana, Syzygium guineense and Entandrophragma exselsum). Measurements of chlorophyll fluorescence, leaf gas exchange, morphology, chemistry and temperature were made at three common gardens along an elevation/temperature gradient. Heat tolerance acclimated to maximum leaf temperature (Tleaf ) across the species. At the warmest sites, the thermal threshold for normal function of photosystem II was exceeded in the species with the highest Tleaf despite their higher heat tolerance. This was not the case in the species with the highest transpiration rates and lowest Tleaf . The results point to two differently effective strategies for managing thermal stress: tolerance through physiological adjustment of leaf osmolality and thylakoid membrane lipid composition, or avoidance through morphological adaptation and transpiratory cooling. More severe photosynthetic heat stress in low-transpiring montane climax species may result in a competitive disadvantage compared to high-transpiring pioneer species with more efficient leaf cooling.
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Affiliation(s)
- Lasse Tarvainen
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, Gothenburg, SE-405 30, Sweden
| | - Maria Wittemann
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, Gothenburg, SE-405 30, Sweden
- Department of Biology, University of Rwanda, University Avenue, PO Box 117, Huye, Rwanda
| | - Myriam Mujawamariya
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, Gothenburg, SE-405 30, Sweden
- Department of Biology, University of Rwanda, University Avenue, PO Box 117, Huye, Rwanda
| | - Aloysie Manishimwe
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, Gothenburg, SE-405 30, Sweden
- Department of Biology, University of Rwanda, University Avenue, PO Box 117, Huye, Rwanda
| | - Etienne Zibera
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, Gothenburg, SE-405 30, Sweden
- Department of Biology, University of Rwanda, University Avenue, PO Box 117, Huye, Rwanda
| | - Bonaventure Ntirugulirwa
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, Gothenburg, SE-405 30, Sweden
- Department of Biology, University of Rwanda, University Avenue, PO Box 117, Huye, Rwanda
- Rwanda Agriculture and Animal Development Board, PO Box 5016, Kigali, Rwanda
| | - Claire Ract
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, Gothenburg, SE-405 30, Sweden
| | - Olivier J L Manzi
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, Gothenburg, SE-405 30, Sweden
- Department of Biology, University of Rwanda, University Avenue, PO Box 117, Huye, Rwanda
| | - Mats X Andersson
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, Gothenburg, SE-405 30, Sweden
| | - Cornelia Spetea
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, Gothenburg, SE-405 30, Sweden
| | - Donat Nsabimana
- School of Forestry and Biodiversity and Biological Sciences, University of Rwanda, Busogo, Rwanda
| | - Göran Wallin
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, Gothenburg, SE-405 30, Sweden
| | - Johan Uddling
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, Gothenburg, SE-405 30, Sweden
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41
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Du B, Zhu Y, Kang H, Liu C. Spatial variations in stomatal traits and their coordination with leaf traits in Quercus variabilis across Eastern Asia. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 789:147757. [PMID: 34058578 DOI: 10.1016/j.scitotenv.2021.147757] [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: 02/10/2021] [Revised: 05/07/2021] [Accepted: 05/10/2021] [Indexed: 05/26/2023]
Abstract
The stomatal traits influence ecosystem carbon-water fluxes and play essential roles that enable plants to adapt to changing environmental conditions. However, how stomatal traits vary along a large climate gradient and whether stomatal traits coordinated with other leaf functional traits in response to environmental changes remain unclear. We investigated the stomatal density (SD), stomatal size (SS), and leaf traits (leaf area (LA), leaf mass per area (LMA), and vein density (VD)) of 44 in situ Quercus variabilis populations across Eastern Asia (24 to 51.8°N, 99 to 137°E) and 15 populations grown in a common garden, and evaluated their relationships with environmental factors. Stepwise multiple regression showed that the SD was significantly associated with mean annual precipitation (MAP), LMA, and VD, and the SS with latitude, mean annual temperature (MAT), mean monthly solar radiation (MMSR), and VD. The SD was positively correlated with the LMA, while the SS was negatively correlated with the VD. The SD and LMA increased with decreasing precipitation, which indicated that they may coordinate to commonly enhance plant resistance against drought. The SS decreased; however, the VD increased with temperature. This implied that plants might further reduce their SS by increasing VD limitations under global warming. In the common garden, plants exhibited a higher SD and VD and lower SS and LA compared to those in the field; however, no relation between the stomatal and leaf traits was observed. Our results suggested that stomatal traits have high environmental plasticity and are highly coordinated with other leaf functional traits in response to environmental changes. Nevertheless, this coordination may have been formed through long-term adaptations, rather than over short time spans.
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Affiliation(s)
- Baoming Du
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yanhua Zhu
- Instrumental Analysis Center, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hongzhang Kang
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China; School of Design, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Chunjiang Liu
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Urban Forest Ecosystem Research Station, State Forestry Administration, Shanghai 200240, China; Shanghai Yangtze River Delta Eco-environmental Change and Management Observation and Research Station, Ministry of Science and Technology, Shanghai 200240, China.
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42
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Carter KR, Wood TE, Reed SC, Butts KM, Cavaleri MA. Experimental warming across a tropical forest canopy height gradient reveals minimal photosynthetic and respiratory acclimation. PLANT, CELL & ENVIRONMENT 2021; 44:2879-2897. [PMID: 34169547 DOI: 10.1111/pce.14134] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Accepted: 06/08/2021] [Indexed: 06/13/2023]
Abstract
Tropical forest canopies cycle vast amounts of carbon, yet we still have a limited understanding of how these critical ecosystems will respond to climate warming. We implemented in situ leaf-level + 3°C experimental warming from the understory to the upper canopy of two Puerto Rican tropical tree species, Guarea guidonia and Ocotea sintenisii. After approximately 1 month of continuous warming, we assessed adjustments in photosynthesis, chlorophyll fluorescence, stomatal conductance, leaf traits and foliar respiration. Warming did not alter net photosynthetic temperature response for either species; however, the optimum temperature of Ocotea understory leaf photosynthetic electron transport shifted upward. There was no Ocotea respiratory treatment effect, while Guarea respiratory temperature sensitivity (Q10 ) was down-regulated in heated leaves. The optimum temperatures for photosynthesis (Topt ) decreased 3-5°C from understory to the highest canopy position, perhaps due to upper canopy stomatal conductance limitations. Guarea upper canopy Topt was similar to the mean daytime temperatures, while Ocotea canopy leaves often operated above Topt . With minimal acclimation to warmer temperatures in the upper canopy, further warming could put these forests at risk of reduced CO2 uptake, which could weaken the overall carbon sink strength of this tropical forest.
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Affiliation(s)
- Kelsey R Carter
- College of Forest Resources and Environmental Science, Michigan Technological University, Houghton, Michigan, USA
- Earth and Environmental Science Division, Los Alamos National Laboratory, Los Alamos, New Mexico, USA
| | - Tana E Wood
- United States Department of Agriculture, Forest Service, International Institute of Tropical Forestry, Jardin Botánico Sur, Río Piedras, Puerto Rico, USA
| | - Sasha C Reed
- U.S. Geological Survey, Southwest Biological Science Center, Moab, Utah, USA
| | - Kaylie M Butts
- College of Forest Resources and Environmental Science, Michigan Technological University, Houghton, Michigan, USA
| | - Molly A Cavaleri
- College of Forest Resources and Environmental Science, Michigan Technological University, Houghton, Michigan, USA
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43
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Cook AM, Berry N, Milner KV, Leigh A. Water availability influences thermal safety margins for leaves. Funct Ecol 2021. [DOI: 10.1111/1365-2435.13868] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Alicia M. Cook
- School of Life Sciences University of Technology Sydney Broadway NSW Australia
| | - Neil Berry
- School of Life Sciences University of Technology Sydney Broadway NSW Australia
| | - Kirsty V. Milner
- School of Life Sciences University of Technology Sydney Broadway NSW Australia
| | - Andrea Leigh
- School of Life Sciences University of Technology Sydney Broadway NSW Australia
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44
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Slot M, Cala D, Aranda J, Virgo A, Michaletz ST, Winter K. Leaf heat tolerance of 147 tropical forest species varies with elevation and leaf functional traits, but not with phylogeny. PLANT, CELL & ENVIRONMENT 2021; 44:2414-2427. [PMID: 33817813 DOI: 10.1111/pce.14060] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 03/29/2021] [Indexed: 06/12/2023]
Abstract
Exceeding thermal thresholds causes irreversible damage and ultimately loss of leaves. The lowland tropics are among the warmest forested biomes, but little is known about heat tolerance of tropical forest plants. We surveyed leaf heat tolerance of sun-exposed leaves from 147 tropical lowland and pre-montane forest species by determining the temperatures at which potential photosystem II efficiency based on chlorophyll a fluorescence started to decrease (TCrit ) and had decreased by 50% (T50 ). TCrit averaged 46.7°C (5th-95th percentile: 43.5°C-49.7°C) and T50 averaged 49.9°C (47.8°C-52.5°C). Heat tolerance partially adjusted to site temperature; TCrit and T50 decreased with elevation by 0.40°C and 0.26°C per 100 m, respectively, while mean annual temperature decreased by 0.63°C per 100 m. The phylogenetic signal in heat tolerance was weak, suggesting that heat tolerance is more strongly controlled by environment than by evolutionary legacies. TCrit increased with the estimated thermal time constant of the leaves, indicating that species with thermally buffered leaves maintain higher heat tolerance. Among lowland species, T50 increased with leaf mass per area, suggesting that in species with structurally more costly leaves the risk of leaf loss during hot spells is reduced. These results provide insight in variation in heat tolerance at local and regional scales.
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Affiliation(s)
- Martijn Slot
- Smithsonian Tropical Research Institute, Panama City, Republic of Panama
| | - Daniela Cala
- Smithsonian Tropical Research Institute, Panama City, Republic of Panama
- Paul H. O'Neill School of Public and Environmental Affairs, Indiana University, Bloomington, Indiana, USA
| | - Jorge Aranda
- Smithsonian Tropical Research Institute, Panama City, Republic of Panama
| | - Aurelio Virgo
- Smithsonian Tropical Research Institute, Panama City, Republic of Panama
| | - Sean T Michaletz
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Klaus Winter
- Smithsonian Tropical Research Institute, Panama City, Republic of Panama
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45
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Flo V, Martínez-Vilalta J, Mencuccini M, Granda V, Anderegg WRL, Poyatos R. Climate and functional traits jointly mediate tree water-use strategies. THE NEW PHYTOLOGIST 2021; 231:617-630. [PMID: 33893652 DOI: 10.1111/nph.17404] [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: 10/19/2020] [Accepted: 04/03/2021] [Indexed: 06/12/2023]
Abstract
Tree water use is central to plant function and ecosystem fluxes. However, it is still unknown how organ-level water-relations traits are coordinated to determine whole-tree water-use strategies in response to drought, and whether this coordination depends on climate. Here we used a global sap flow database (SAPFLUXNET) to study the response of water use, in terms of whole-tree canopy conductance (G), to vapour pressure deficit (VPD) and to soil water content (SWC) for 142 tree species. We investigated the individual and coordinated effect of six water-relations traits (vulnerability to embolism, Huber value, hydraulic conductivity, turgor-loss point, rooting depth and leaf size) on water-use parameters, also accounting for the effect of tree height and climate (mean annual precipitation, MAP). Reference G and its sensitivity to VPD were tightly coordinated with water-relations traits rather than with MAP. Species with efficient xylem transport had higher canopy conductance but also higher sensitivity to VPD. Moreover, we found that angiosperms had higher reference G and higher sensitivity to VPD than did gymnosperms. Our results highlight the need to consider trait integration and reveal the complications and challenges of defining a single, whole-plant resource use spectrum ranging from 'acquisitive' to 'conservative'.
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Affiliation(s)
- Victor Flo
- CREAF, Bellaterra (Cerdanyola del Vallès), Catalonia, 08193, Spain
- Univ Autònoma de Barcelona, Bellaterra (Cerdanyola del Vallès), Catalonia, 08193, Spain
| | - Jordi Martínez-Vilalta
- CREAF, Bellaterra (Cerdanyola del Vallès), Catalonia, 08193, Spain
- Univ Autònoma de Barcelona, Bellaterra (Cerdanyola del Vallès), Catalonia, 08193, Spain
| | - Maurizio Mencuccini
- CREAF, Bellaterra (Cerdanyola del Vallès), Catalonia, 08193, Spain
- ICREA, Barcelona, 08010, Spain
| | - Victor Granda
- CREAF, Bellaterra (Cerdanyola del Vallès), Catalonia, 08193, Spain
| | - William R L Anderegg
- School of Biological Sciences, University of Utah, Salt Lake City, UT, 84112, USA
| | - Rafael Poyatos
- CREAF, Bellaterra (Cerdanyola del Vallès), Catalonia, 08193, Spain
- Univ Autònoma de Barcelona, Bellaterra (Cerdanyola del Vallès), Catalonia, 08193, Spain
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46
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Tiwari R, Gloor E, da Cruz WJA, Schwantes Marimon B, Marimon-Junior BH, Reis SM, de Souza IA, Krause HG, Slot M, Winter K, Ashley D, Béu RG, Borges CS, Da Cunha M, Fauset S, Ferreira LDS, Gonçalves MDA, Lopes TT, Marques EQ, Mendonça NG, Mendonça NG, Noleto PT, de Oliveira CHL, Oliveira MA, Pireda S, Dos Santos Prestes NCC, Santos DM, Santos EB, da Silva ELS, de Souza IA, de Souza LJ, Vitória AP, Foyer CH, Galbraith D. Photosynthetic quantum efficiency in south-eastern Amazonian trees may be already affected by climate change. PLANT, CELL & ENVIRONMENT 2021; 44:2428-2439. [PMID: 32339294 DOI: 10.1111/pce.13770] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 03/28/2020] [Indexed: 06/11/2023]
Abstract
Tropical forests are experiencing unprecedented high-temperature conditions due to climate change that could limit their photosynthetic functions. We studied the high-temperature sensitivity of photosynthesis in a rainforest site in southern Amazonia, where some of the highest temperatures and most rapid warming in the Tropics have been recorded. The quantum yield (Fv /Fm ) of photosystem II was measured in seven dominant tree species using leaf discs exposed to varying levels of heat stress. T50 was calculated as the temperature at which Fv /Fm was half the maximum value. T5 is defined as the breakpoint temperature, at which Fv /Fm decline was initiated. Leaf thermotolerance in the rapidly warming southern Amazonia was the highest recorded for forest tree species globally. T50 and T5 varied between species, with one mid-storey species, Amaioua guianensis, exhibiting particularly high T50 and T5 values. While the T50 values of the species sampled were several degrees above the maximum air temperatures experienced in southern Amazonia, the T5 values of several species are now exceeded under present-day maximum air temperatures.
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Affiliation(s)
| | | | | | | | - Ben Hur Marimon-Junior
- Universidade do Estado de Mato Grosso, Laboratório de Ecologia Vegetal, Nova Xavantina, Brazil
| | - Simone M Reis
- Universidade do Estado de Mato Grosso, Laboratório de Ecologia Vegetal, Nova Xavantina, Brazil
| | - Igor Araújo de Souza
- Universidade do Estado de Mato Grosso, Laboratório de Ecologia Vegetal, Nova Xavantina, Brazil
| | - Heinrich G Krause
- Smithsonian Tropical Research Institute, Panama City, Panama
- Institute of Plant Biochemistry, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Martijn Slot
- Smithsonian Tropical Research Institute, Panama City, Panama
| | - Klaus Winter
- Smithsonian Tropical Research Institute, Panama City, Panama
| | - David Ashley
- School of Geography, University of Leeds, Leeds, UK
| | - Raiane G Béu
- Universidade do Estado de Mato Grosso, Laboratório de Ecologia Vegetal, Nova Xavantina, Brazil
| | - Camila S Borges
- Universidade do Estado de Mato Grosso, Laboratório de Ecologia Vegetal, Nova Xavantina, Brazil
| | - Maura Da Cunha
- Laboratório de Biologia Celular e Tecidual, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos Dos Goytacazes, Brazil
| | - Sophie Fauset
- Faculty of Science and Engineering, School of Geography, Earth and Environmental Sciences, University of Plymouth, Plymouth, UK
| | - Laura D S Ferreira
- Universidade do Estado de Mato Grosso, Laboratório de Ecologia Vegetal, Nova Xavantina, Brazil
| | | | - Thaynara T Lopes
- Universidade do Estado de Mato Grosso, Laboratório de Ecologia Vegetal, Nova Xavantina, Brazil
| | - Eduardo Q Marques
- Universidade do Estado de Mato Grosso, Laboratório de Ecologia Vegetal, Nova Xavantina, Brazil
| | - Natalia G Mendonça
- Universidade do Estado de Mato Grosso, Laboratório de Ecologia Vegetal, Nova Xavantina, Brazil
| | - Natana G Mendonça
- Universidade do Estado de Mato Grosso, Laboratório de Ecologia Vegetal, Nova Xavantina, Brazil
| | - Pedro T Noleto
- Universidade do Estado de Mato Grosso, Laboratório de Ecologia Vegetal, Nova Xavantina, Brazil
| | | | - Milene A Oliveira
- Universidade do Estado de Mato Grosso, Laboratório de Ecologia Vegetal, Nova Xavantina, Brazil
| | - Saulo Pireda
- Laboratório de Biologia Celular e Tecidual, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos Dos Goytacazes, Brazil
| | | | - Denilson M Santos
- Universidade do Estado de Mato Grosso, Laboratório de Ecologia Vegetal, Nova Xavantina, Brazil
| | - Eduarda B Santos
- Universidade do Estado de Mato Grosso, Laboratório de Ecologia Vegetal, Nova Xavantina, Brazil
| | | | - Izabel A de Souza
- Universidade do Estado de Mato Grosso, Laboratório de Ecologia Vegetal, Nova Xavantina, Brazil
| | - Luciana J de Souza
- Universidade do Estado de Mato Grosso, Laboratório de Ecologia Vegetal, Nova Xavantina, Brazil
| | - Angela P Vitória
- Laboratório de Ciências Ambientais, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos Dos Goytacazes, Brazil
| | - Christine H Foyer
- Faculty of Biological Sciences, University of Leeds, Leeds, UK
- School of Biosciences, University of Birmingham, Birmingham, UK
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47
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Still CJ, Rastogi B, Page GFM, Griffith DM, Sibley A, Schulze M, Hawkins L, Pau S, Detto M, Helliker BR. Imaging canopy temperature: shedding (thermal) light on ecosystem processes. THE NEW PHYTOLOGIST 2021; 230:1746-1753. [PMID: 33666251 DOI: 10.1111/nph.17321] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 02/03/2021] [Indexed: 06/12/2023]
Abstract
Canopy temperature Tcan is a key driver of plant function that emerges as a result of interacting biotic and abiotic processes and properties. However, understanding controls on Tcan and forecasting canopy responses to weather extremes and climate change are difficult due to sparse measurements of Tcan at appropriate spatial and temporal scales. Burgeoning observations of Tcan from thermal cameras enable evaluation of energy budget theory and better understanding of how environmental controls, leaf traits and canopy structure influence temperature patterns. The canopy scale is relevant for connecting to remote sensing and testing biosphere model predictions. We anticipate that future breakthroughs in understanding of ecosystem responses to climate change will result from multiscale observations of Tcan across a range of ecosystems.
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Affiliation(s)
- Christopher J Still
- Forest Ecosystems and Society, Oregon State University, Corvallis, OR, 97331, USA
| | - Bharat Rastogi
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, 80309, USA
- Global Monitoring Laboratory, National Oceanic and Atmospheric Administration, Boulder, CO, 80305, USA
| | - Gerald F M Page
- Forest Ecosystems and Society, Oregon State University, Corvallis, OR, 97331, USA
| | - Dan M Griffith
- Forest Ecosystems and Society, Oregon State University, Corvallis, OR, 97331, USA
| | - Adam Sibley
- Forest Ecosystems and Society, Oregon State University, Corvallis, OR, 97331, USA
| | - Mark Schulze
- H.J. Andrews Experimental Forest, Oregon State University, Blue River, OR, 97413, USA
| | - Linnia Hawkins
- Forest Ecosystems and Society, Oregon State University, Corvallis, OR, 97331, USA
| | - Stephanie Pau
- Department of Geography, Florida State University, Tallahassee, FL, 32304, USA
| | - Matteo Detto
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, 08540, USA
- Smithsonian Tropical Research Institute, Balboa, Panama
| | - Brent R Helliker
- Department of Biology, University of Pennsylvania, 433 S. University Avenue, Philadelphia, PA, 19104, USA
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48
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Boanares D, Lemos-Filho JP, Isaias RMS, França MGC. Photosynthetic heat tolerance in plants with different foliar water -uptake strategies. AMERICAN JOURNAL OF BOTANY 2021; 108:811-819. [PMID: 33891308 DOI: 10.1002/ajb2.1648] [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: 08/10/2020] [Accepted: 11/24/2020] [Indexed: 06/12/2023]
Abstract
PREMISE The distribution and even the survival of plant species are influenced by temperature. In an old climatically buffered infertile landscape (OCBIL) in Brazil, we previously characterized different strategies for foliar water uptake (FWU). It is possible that photosystem II tolerance to heat and excessive light intensity varies among species with different FWU capacities. METHODS The relationship between FWU, photoinhibition, and thermotolerance was investigated in seven species from this ecosystem. RESULTS The species with slow water absorption and high water absorption are those that presented less photoinhibition. Contrastingly, the species that have fast and low water absorption presented greater thermotolerance when their leaves are totally hydrated. However, when there is greater leaf dehydration, the most thermotolerant species were those with slow but high water absorption. CONCLUSIONS Foliar water uptake is an important trait for plants to tolerate excessive light intensity and higher temperatures. Plants in this OCBIL may be differentially affected by future global warming, and the best strategy to deal with this expected climate change is with slow and high absorption of water.
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Affiliation(s)
- Daniela Boanares
- Departamento de Botânica, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, CEP 31270-901, Brasil
| | - José P Lemos-Filho
- Departamento de Botânica, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, CEP 31270-901, Brasil
| | - Rosy M S Isaias
- Departamento de Botânica, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, CEP 31270-901, Brasil
| | - Marcel G C França
- Departamento de Botânica, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, CEP 31270-901, Brasil
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49
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Tserej O, Feeley KJ. Variation in leaf temperatures of tropical and subtropical trees are related to leaf thermoregulatory traits and not geographic distributions. Biotropica 2021. [DOI: 10.1111/btp.12919] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Olga Tserej
- Biology Department University of Miami Coral Gables FL USA
- Fairchild Tropical Botanic Garden Coral Gables FL USA
| | - Kenneth J. Feeley
- Biology Department University of Miami Coral Gables FL USA
- Fairchild Tropical Botanic Garden Coral Gables FL USA
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50
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Cavaleri MA. Cold-blooded forests in a warming world. THE NEW PHYTOLOGIST 2020; 228:1455-1457. [PMID: 33011978 DOI: 10.1111/nph.16916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 09/01/2020] [Indexed: 06/11/2023]
Affiliation(s)
- Molly A Cavaleri
- College of Forest Resources & Environmental Science, Michigan Technological University, Houghton, MI, 49931, USA
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