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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. Physiol Plant 2024; 176:e14326. [PMID: 38708565 DOI: 10.1111/ppl.14326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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Huang J, Ladd SN, Ingrisch J, Kübert A, Meredith LK, van Haren J, Bamberger I, Daber LE, Kühnhammer K, Bailey K, Hu J, Fudyma J, Shi L, Dippold MA, Meeran K, Miller L, O'Brien MJ, Yang H, Herrera-Ramírez D, Hartmann H, Trumbore S, Bahn M, Werner C, Lehmann MM. The mobilization and transport of newly fixed carbon are driven by plant water use in an experimental rainforest under drought. J Exp Bot 2024; 75:2545-2557. [PMID: 38271585 DOI: 10.1093/jxb/erae030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Accepted: 01/24/2024] [Indexed: 01/27/2024]
Abstract
Non-structural carbohydrates (NSCs) are building blocks for biomass and fuel metabolic processes. However, it remains unclear how tropical forests mobilize, export, and transport NSCs to cope with extreme droughts. We combined drought manipulation and ecosystem 13CO2 pulse-labeling in an enclosed rainforest at Biosphere 2, assessed changes in NSCs, and traced newly assimilated carbohydrates in plant species with diverse hydraulic traits and canopy positions. We show that drought caused a depletion of leaf starch reserves and slowed export and transport of newly assimilated carbohydrates below ground. Drought effects were more pronounced in conservative canopy trees with limited supply of new photosynthates and relatively constant water status than in those with continual photosynthetic supply and deteriorated water status. We provide experimental evidence that local utilization, export, and transport of newly assimilated carbon are closely coupled with plant water use in canopy trees. We highlight that these processes are critical for understanding and predicting tree resistance and ecosystem fluxes in tropical forest under drought.
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Affiliation(s)
- Jianbei Huang
- Max Planck Institute for Biogeochemistry, D-07745 Jena, Germany
| | - S Nemiah Ladd
- Ecosystem Physiology, Albert-Ludwig-University of Freiburg, Freiburg, Germany
- Department of Environmental Sciences, University of Basel, Bernoullistrasse 30, 4056 Basel, Switzerland
| | - Johannes Ingrisch
- Ecosystem Physiology, Albert-Ludwig-University of Freiburg, Freiburg, Germany
- Department of Ecology, University of Innsbruck, Sternwartestr 15, 6020 Innsbruck, Austria
| | - Angelika Kübert
- Ecosystem Physiology, Albert-Ludwig-University of Freiburg, Freiburg, Germany
| | - Laura K Meredith
- School of Natural Resources and the Environment, University of Arizona, 1064 E. Lowell St., Tucson, AZ 85721, USA
- Biosphere 2, University of Arizona, 32540 S. Biosphere Rd, Oracle, AZ 85739, USA
| | - Joost van Haren
- Biosphere 2, University of Arizona, 32540 S. Biosphere Rd, Oracle, AZ 85739, USA
- Honors College, University of Arizona, 1101 East Mabel Street, Tucson, AZ 85719, USA
| | - Ines Bamberger
- Ecosystem Physiology, Albert-Ludwig-University of Freiburg, Freiburg, Germany
- Atmospheric Chemistry Group, University of Bayreuth (BayCEER), Germany
| | - L Erik Daber
- Ecosystem Physiology, Albert-Ludwig-University of Freiburg, Freiburg, Germany
| | - Kathrin Kühnhammer
- Ecosystem Physiology, Albert-Ludwig-University of Freiburg, Freiburg, Germany
| | - Kinzie Bailey
- School of Natural Resources and the Environment, University of Arizona, 1064 E. Lowell St., Tucson, AZ 85721, USA
| | - Jia Hu
- School of Natural Resources and the Environment, University of Arizona, 1064 E. Lowell St., Tucson, AZ 85721, USA
| | - Jane Fudyma
- Department of Environmental Science, University of Arizona, Tucson, AZ, USA
- Department of Land, Air, and Water Resources, University of California, Davis, CA, USA
| | - Lingling Shi
- Biogeochemistry of Agroecosystems, University of Göttingen, Göttingen, Germany
- Geo-Biosphere Interactions, University of Tuebingen, Tuebingen, Germany
| | - Michaela A Dippold
- Biogeochemistry of Agroecosystems, University of Göttingen, Göttingen, Germany
- Geo-Biosphere Interactions, University of Tuebingen, Tuebingen, Germany
| | - Kathiravan Meeran
- Department of Ecology, University of Innsbruck, Sternwartestr 15, 6020 Innsbruck, Austria
| | - Luke Miller
- Biosphere 2, University of Arizona, 32540 S. Biosphere Rd, Oracle, AZ 85739, USA
| | - Michael J O'Brien
- Estación Experimental de Zonas Áridas, Consejo Superior de Investigaciones Científicas, Almería, Spain
| | - Hui Yang
- Max Planck Institute for Biogeochemistry, D-07745 Jena, Germany
| | | | - Henrik Hartmann
- Max Planck Institute for Biogeochemistry, D-07745 Jena, Germany
- Institute for Forest Protection, Julius Kühn Institute (JKI) - Federal Research Centre for Cultivated Plants, Erwin-Baur-Straße 27, D-06484 Quedlinburg, Germany
| | - Susan Trumbore
- Max Planck Institute for Biogeochemistry, D-07745 Jena, Germany
| | - Michael Bahn
- Department of Ecology, University of Innsbruck, Sternwartestr 15, 6020 Innsbruck, Austria
| | - Christiane Werner
- Ecosystem Physiology, Albert-Ludwig-University of Freiburg, Freiburg, Germany
| | - Marco M Lehmann
- Swiss Federal Research Institute WSL, 8903 Birmensdorf, Switzerland
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Jin N, Yu X, Dong J, Duan M, Mo Y, Feng L, Bai R, Zhao J, Song J, Dossa GGO, Lu H. Vertical variation in leaf functional traits of Parashorea chinensis with different canopy layers. Front Plant Sci 2024; 15:1335524. [PMID: 38348271 PMCID: PMC10859428 DOI: 10.3389/fpls.2024.1335524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 01/08/2024] [Indexed: 02/15/2024]
Abstract
Introduction Canopy species need to shift their ecological adaptation to improve light and water resources utilization, and the study of intraspecific variations in plant leaf functional traits based at individual scale is of great significance for evaluating plant adaptability to climate change. Methods In this study, we evaluate how leaf functional traits of giant trees relate to spatial niche specialization along a vertical gradient. We sampled the tropical flagship species of Parashorea chinensis around 60 meters tall and divided their crowns into three vertical layers. Fourteen key leaf functional traits including leaf morphology, photosynthetic, hydraulic and chemical physiology were measured at each canopy layer to investigate the intraspecific variation of leaf traits and the interrelationships between different functional traits. Additionally, due to the potential impact of different measurement methods (in-situ and ex-situ branch) on photosynthetic physiological parameters, we also compared the effects of these two gas exchange measurements. Results and discussion In-situ measurements revealed that most leaf functional traits of individual-to-individual P. chinensis varied significantly at different canopy heights. Leaf hydraulic traits such as midday leaf water potential (MWP) and leaf osmotic potential (OP) were insignificantly correlated with leaf photosynthetic physiological traits such as maximal net assimilation rate per mass (A mass). In addition, great discrepancies were found between in-situ and ex-situ measurements of photosynthetic parameters. The ex-situ measurements caused a decrease by 53.63%, 27.86%, and 38.05% in A mass, and a decrease of 50.00%, 19.21%, and 27.90% in light saturation point compared to the in-situ measurements. These findings provided insights into our understanding of the response mechanisms of P. chinensis to micro-habitat in Xishuangbanna tropical seasonal rainforests and the fine scale adaption of different resultant of decoupled traits, which have implications for understanding ecological adaption strategies of P. chinensis under environmental changes.
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Affiliation(s)
- Nan Jin
- School of Ecology and Environment Science, Yunnan University, Kunming, China
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, China
- National Forest Ecosystem Research Station at Xishuangbanna, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, China
- Xishuangbanna Forest Ecosystem Yunnan Field Scientific Observation Research Station, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, China
| | - Xiaocheng Yu
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, China
- National Forest Ecosystem Research Station at Xishuangbanna, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, China
- Xishuangbanna Forest Ecosystem Yunnan Field Scientific Observation Research Station, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, China
| | - Jinlong Dong
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, China
- National Forest Ecosystem Research Station at Xishuangbanna, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, China
- Xishuangbanna Forest Ecosystem Yunnan Field Scientific Observation Research Station, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, China
| | - Mengcheng Duan
- Qianyanzhou Ecological Research Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Yuxuan Mo
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, China
| | - Leiyun Feng
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, China
- National Forest Ecosystem Research Station at Xishuangbanna, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, China
- Xishuangbanna Forest Ecosystem Yunnan Field Scientific Observation Research Station, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, China
| | - Rong Bai
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, China
- National Forest Ecosystem Research Station at Xishuangbanna, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, China
- Xishuangbanna Forest Ecosystem Yunnan Field Scientific Observation Research Station, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, China
| | - Jianli Zhao
- School of Ecology and Environment Science, Yunnan University, Kunming, China
| | - Jia Song
- School of Environmental and Geographical Science, Shanghai Normal University, Shanghai, China
| | - Gbadamassi Gouvide Olawole Dossa
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, China
| | - Huazheng Lu
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, China
- National Forest Ecosystem Research Station at Xishuangbanna, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, China
- Xishuangbanna Forest Ecosystem Yunnan Field Scientific Observation Research Station, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, China
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Huang Q, Xu J, Wong JP, Radeloff VC, Songer M. Prioritizing global tall forests toward the 30 × 30 goals. Conserv Biol 2023; 37:e14135. [PMID: 37377172 DOI: 10.1111/cobi.14135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 05/26/2023] [Accepted: 06/05/2023] [Indexed: 06/29/2023]
Abstract
The Global Deal for Nature sets an ambitious goal to protect 30% of Earth's land and ocean by 2030. The 30 × 30 initiative is a way to allocate conservation resources and extend protection to conserve vulnerable and underprotected ecosystems while reducing carbon emissions to combat climate change. However, most prioritization methods for identifying high-value conservation areas are based on thematic attributes and do not consider vertical habitat structure. Global tall forests represent a rare vertical habitat structure that harbors high species richness in various taxonomic groups and is associated with large amounts of aboveground biomass. Global tall forests should be prioritized when planning global protected areas toward reaching the 30 × 30 goals. We examined the spatial distribution of global tall forests based on the Global Canopy Height 2020 product. We defined global tall forests as areas with the average canopy height above 3 thresholds (20, 25, and 30 m). We quantified the spatial distribution and protection level of global tall forests in high-protection zones, where the 30 × 30 goals are being met or are within reach, and low-protection zones, where there is a low chance of reaching 30 × 30 goals. We quantified the protection level by computing the percentage of global tall forest area protected based on the 2017 World Database on Protected Areas. We also determined the global extent and protection level of undisturbed, mature, tall forests based on the 2020 Global Intact Forest Landscapes mask. In most cases, the percentage of protection decreased as forest height reached the top strata. In the low-protection zones, <30% of forests were protected in almost all tall forest strata. In countries such as Brazil, tall forests had a higher percentage of protection (consistently >30%) compared to forests of lower height, presenting a more effective conservation model than in countries such as the United States, where forest protection was almost uniformly <30% across height strata. Our results show an urgent need to target forest conservation in the greatest height strata, particularly in high-protection areas, where most global tall forests are found. Vegetation vertical structure can inform the decision-making process toward the 30 × 30 goals because it can be used to identify areas of high conservation value for biodiversity protection which also contribute to carbon sequestration.
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Affiliation(s)
- Qiongyu Huang
- Conservation Ecology Center, Smithsonian's National Zoo and Conservation Biology Institute, Front Royal, Virginia, USA
| | - Jin Xu
- Conservation Ecology Center, Smithsonian's National Zoo and Conservation Biology Institute, Front Royal, Virginia, USA
| | - Jesse Pan Wong
- Conservation Ecology Center, Smithsonian's National Zoo and Conservation Biology Institute, Front Royal, Virginia, USA
- Department of Geography, Kent State University, Kent, Ohio, USA
| | - Volker C Radeloff
- Forest and Wildlife Ecology Department, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Melissa Songer
- Conservation Ecology Center, Smithsonian's National Zoo and Conservation Biology Institute, Front Royal, Virginia, USA
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5
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Liu F, Liu H, Adalibieke W, Peng Z, Liang B, Feng S, Shi L, Zhu X. Decline in stability of forest productivity in the tropics as determined by canopy water content. iScience 2023; 26:107211. [PMID: 37456836 PMCID: PMC10339190 DOI: 10.1016/j.isci.2023.107211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 05/19/2023] [Accepted: 06/22/2023] [Indexed: 07/18/2023] Open
Abstract
The impacts of low soil moisture (SM) and high vapour pressure deficit (VPD) on tree's photosynthesis and productivity are ultimately realized by changing water content in the canopy leaves. In this study, variations in canopy water content (CWC) that can be detected from microwave remotely sensed vegetation optical depth (VOD) have been proposed as a promising measure of vegetation water status, and we first reported that the regulation of CWC on productivity stability is universally applicable for global forests. Results of structural equation model (SEM) also confirmed the significant negative effect of CWC on coefficient of variation (CV) of productivity, indicating that the decrease in CWC could inevitably induce the instability of forest productivity under climate change. The most significant decrease (p < 0.01) of CWC is observed primarily in evergreen broadleaf forest in the tropics, implying an increasing instability of the most important carbon sink in terrestrial ecosystem.
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Affiliation(s)
- Feng Liu
- College of Urban and Environmental Sciences and MOE Laboratory for Earth Surface Processes, Peking University, Beijing 100871, China
| | - Hongyan Liu
- College of Urban and Environmental Sciences and MOE Laboratory for Earth Surface Processes, Peking University, Beijing 100871, China
| | - Wulahati Adalibieke
- College of Urban and Environmental Sciences and MOE Laboratory for Earth Surface Processes, Peking University, Beijing 100871, China
| | - Zhaoyu Peng
- College of Urban and Environmental Sciences and MOE Laboratory for Earth Surface Processes, Peking University, Beijing 100871, China
| | - Boyi Liang
- College of Forestry, Precision Forestry Key Laboratory of Beijing, Beijing Forestry University, Beijing 100083, China
| | - Siwen Feng
- College of Urban and Environmental Sciences and MOE Laboratory for Earth Surface Processes, Peking University, Beijing 100871, China
| | - Liang Shi
- College of Urban and Environmental Sciences and MOE Laboratory for Earth Surface Processes, Peking University, Beijing 100871, China
| | - Xinrong Zhu
- College of Urban and Environmental Sciences and MOE Laboratory for Earth Surface Processes, Peking University, Beijing 100871, China
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Ferdous J, Islam M, Rahman M. The role of tree size, wood anatomical and leaf stomatal traits in shaping tree hydraulic efficiency and safety in a South Asian tropical moist forest. Glob Ecol Conserv 2023. [DOI: 10.1016/j.gecco.2023.e02453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023] Open
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Wu C, Wang Y, Sun H. Targeted and untargeted metabolomics reveals deep analysis of drought stress responses in needles and roots of Pinus taeda seedlings. Front Plant Sci 2023; 13:1031466. [PMID: 36798806 PMCID: PMC9927248 DOI: 10.3389/fpls.2022.1031466] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 12/28/2022] [Indexed: 06/01/2023]
Abstract
Drought stress is one of major environmental stresses affecting plant growth and yield. Although Pinus taeda trees are planted in rainy southern China, local drought sometime occurs and can last several months, further affecting their growth and resin production. In this study, P. taeda seedlings were treated with long-term drought (42 d), and then targeted and untargeted metabolomics analysis were carried out to evaluate drought tolerance of P. taeda. Targeted metabolomics analysis showed that levels of some sugars, phytohormones, and amino acids significantly increased in the roots and needles of water-stressed (WS) P. taeda seedlings, compared with well-watered (WW) pine seedlings. These metabolites included sucrose in pine roots, the phytohormones abscisic acid and sacylic acid in pine needles, the phytohormone gibberellin (GA4) and the two amino acids, glycine and asparagine, in WS pine roots. Compared with WW pine seedlings, the neurotransmitter acetylcholine significantly increased in needles of WS pine seedlings, but significantly reduced in their roots. The neurotransmitters L-glutamine and hydroxytyramine significantly increased in roots and needles of WS pine seedlings, respectively, compared with WW pine seedlings, but the neurotransmitter noradrenaline significantly reduced in needles of WS pine seedlings. Levels of some unsaturated fatty acids significantly reduced in roots or needles of WS pine seedlings, compared with WW pine seedlings, such as linoleic acid, oleic acid, myristelaidic acid, myristoleic acid in WS pine roots, and palmitelaidic acid, erucic acid, and alpha-linolenic acid in WS pine needles. However, three saturated fatty acids significantly increased in WS pine seedlings, i.e., dodecanoic acid in WS pine needles, tricosanoic acid and heptadecanoic acid in WS pine roots. Untargeted metabolomics analysis showed that levels of some metabolites increased in WS pine seedlings, especially sugars, long-chain lipids, flavonoids, and terpenoids. A few of specific metabolites increased greatly, such as androsin, piceatanol, and panaxatriol in roots and needles of WS pine seedlings. Comparing with WW pine seedlings, it was found that the most enriched pathways in WS pine needles included flavone and flavonol biosynthesis, ABC transporters, diterpenoid biosynthesis, plant hormone signal transduction, and flavonoid biosynthesis; in WS pine roots, the most enriched pathways included tryptophan metabolism, caffeine metabolism, sesquiterpenoid and triterpenoid biosynthesis, plant hormone signal transduction, biosynthesis of phenylalanine, tyrosine, and tryptophan. Under long-term drought stress, P. taeda seedlings showed their own metabolomics characteristics, and some new metabolites and biosynthesis pathways were found, providing a guideline for breeding drought-tolerant cultivars of P. taeda.
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Affiliation(s)
- Chu Wu
- College of Horticulture & Gardening, Yangtze University, Jingzhou, Hubei, China
| | - Yun Wang
- College of Life Sciences, Yangtze University, Jingzhou, Hubei, China
| | - Honggang Sun
- Institute of Subtropic Forestry, Chinese Academy of Forestry, Fuyang, Zhejiang, China
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8
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Helmer EH, Kay S, Marcano-Vega H, Powers JS, Wood TE, Zhu X, Gwenzi D, Ruzycki TS. Multiscale predictors of small tree survival across a heterogeneous tropical landscape. PLoS One 2023; 18:e0280322. [PMID: 36920898 PMCID: PMC10016699 DOI: 10.1371/journal.pone.0280322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 12/27/2022] [Indexed: 03/16/2023] Open
Abstract
Uncertainties about controls on tree mortality make forest responses to land-use and climate change difficult to predict. We tracked biomass of tree functional groups in tropical forest inventories across Puerto Rico and the U.S. Virgin Islands, and with random forests we ranked 86 potential predictors of small tree survival (young or mature stems 2.5-12.6 cm diameter at breast height). Forests span dry to cloud forests, range in age, geology and past land use and experienced severe drought and storms. When excluding species as a predictor, top predictors are tree crown ratio and height, two to three species traits and stand to regional factors reflecting local disturbance and the system state (widespread recovery, drought, hurricanes). Native species, and species with denser wood, taller maximum height, or medium typical height survive longer, but short trees and species survive hurricanes better. Trees survive longer in older stands and with less disturbed canopies, harsher geoclimates (dry, edaphically dry, e.g., serpentine substrates, and highest-elevation cloud forest), or in intervals removed from hurricanes. Satellite image phenology and bands, even from past decades, are top predictors, being sensitive to vegetation type and disturbance. Covariation between stand-level species traits and geoclimate, disturbance and neighboring species types may explain why most neighbor variables, including introduced vs. native species, had low or no importance, despite univariate correlations with survival. As forests recovered from a hurricane in 1998 and earlier deforestation, small trees of introduced species, which on average have lighter wood, died at twice the rate of natives. After hurricanes in 2017, the total biomass of trees ≥12.7 cm dbh of the introduced species Spathodea campanulata spiked, suggesting that more frequent hurricanes might perpetuate this light-wooded species commonness. If hurricane recovery favors light-wooded species while drought favors others, climate change influences on forest composition and ecosystem services may depend on the frequency and severity of extreme climate events.
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Affiliation(s)
- Eileen H. Helmer
- USDA Forest Service, International Institute of Tropical Forestry, Río Piedras, Puerto Rico, United States of America
- * E-mail:
| | - Shannon Kay
- USDA Forest Service, Rocky Mountain Research Station Fort Collins, Fort Collins, Colorado, United States of America
| | - Humfredo Marcano-Vega
- USDA Forest Service, International Institute of Tropical Forestry, Río Piedras, Puerto Rico, United States of America
- USDA Forest Service, Southern Research Station, Asheville, NC, United States of America
| | - Jennifer S. Powers
- Departments of Ecology, Evolution and Behavior and Plant and Microbial Biology, University of Minnesota, St. Paul, Minnesota, United States of America
| | - Tana E. Wood
- USDA Forest Service, International Institute of Tropical Forestry, Río Piedras, Puerto Rico, United States of America
| | - Xiaolin Zhu
- Department of Land Surveying and Geo-Informatics, The Hong Kong Polytechnic University, Hung Hom, Hong Kong
| | - David Gwenzi
- Department of Environmental Science & Management, Cal Poly Humboldt State University, Arcata, California, United States of America
| | - Thomas S. Ruzycki
- Center for Environmental Management of Military Lands, Colorado State University, Fort Collins, Colorado, United States of America
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