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Qu Z, Lin C, Zhao H, Chen T, Yao X, Wang X, Yang Y, Chen G. Above- and belowground phenology responses of subtropical Chinese fir (Cunninghamia lanceolata) to soil warming, precipitation exclusion and their interaction. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 933:173147. [PMID: 38740199 DOI: 10.1016/j.scitotenv.2024.173147] [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: 01/07/2024] [Revised: 05/08/2024] [Accepted: 05/09/2024] [Indexed: 05/16/2024]
Abstract
Plant phenology plays an important role in nutrient cycling and carbon balance in forest ecosystems, but its response to the interaction of global warming and precipitation reduction remains unclear. In this study, an experiment with factorial soil warming (ambient, ambient +5 °C) and precipitation exclusion (ambient, ambient -50 %) was conducted in a subtropical Chinese fir (Cunninghamia lanceolata) plantation. We investigated the effects of soil warming, precipitation exclusion, and their interactions on Chinese fir phenology involving tree height and fine root growth. In the meantime, the impact of tree height growth and related climatic factors on fine root production was also assessed. The results showed that: (1) more variable phenology responses were observed in fine root growth than in tree height growth to the climatic treatments; the duration of fine root growth and tree height growth was significantly reduced by the precipitation exclusion and warming treatment, respectively; phenology differences of fine root and tree height growth caused by the solo warming and precipitation exclusion treatment were further enhanced by the combined treatment; and despite the greater inter-annual phenology stability of tree height growth than that of fine root growth, both of them showed insignificant response to all the climate treatments; (2) asynchrony of phenology between tree height and fine root growth was significantly enlarged by solo warming and precipitation exclusion treatments, and further enlarged by the combined treatment; (3) fine root production was significantly and positively correlated with air, and soil temperature, and tree height growth as well, which was altered by warming and precipitation exclusion treatments. Our results demonstrated that climatic changes significantly and differently alter phenology of, and extend the phenology asynchrony between, above and below ground plant components, and also highlight the climate-sensitive and variable nature of root phenology. Overall, these phenology responses to climatic change may weaken the close link between fine root production and tree height growth, which may result in temporal mismatch between nutrient demand and supply in Chinese fir plantation.
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Affiliation(s)
- Zekun Qu
- Key Laboratory of Humid Subtropical Eco-geographical Process of Ministry of Education, School of Geographical Sciences, Fujian Normal University, Fuzhou, China; Fujian Sanming Forest Ecosystem National Observation and Research Station, Sanming, China; State Key Laboratory of Humid Subtropical Mountain Ecology, Fujian Normal University, Fuzhou, China
| | - Chengfang Lin
- Key Laboratory of Humid Subtropical Eco-geographical Process of Ministry of Education, School of Geographical Sciences, Fujian Normal University, Fuzhou, China; Fujian Sanming Forest Ecosystem National Observation and Research Station, Sanming, China; State Key Laboratory of Humid Subtropical Mountain Ecology, Fujian Normal University, Fuzhou, China.
| | - Haiying Zhao
- Key Laboratory of Humid Subtropical Eco-geographical Process of Ministry of Education, School of Geographical Sciences, Fujian Normal University, Fuzhou, China; Fujian Sanming Forest Ecosystem National Observation and Research Station, Sanming, China; State Key Laboratory of Humid Subtropical Mountain Ecology, Fujian Normal University, Fuzhou, China
| | - Tingting Chen
- Key Laboratory of Humid Subtropical Eco-geographical Process of Ministry of Education, School of Geographical Sciences, Fujian Normal University, Fuzhou, China; Fujian Sanming Forest Ecosystem National Observation and Research Station, Sanming, China; State Key Laboratory of Humid Subtropical Mountain Ecology, Fujian Normal University, Fuzhou, China
| | - Xiaodong Yao
- Key Laboratory of Humid Subtropical Eco-geographical Process of Ministry of Education, School of Geographical Sciences, Fujian Normal University, Fuzhou, China; Fujian Sanming Forest Ecosystem National Observation and Research Station, Sanming, China; State Key Laboratory of Humid Subtropical Mountain Ecology, Fujian Normal University, Fuzhou, China
| | - Xiaohong Wang
- Key Laboratory of Humid Subtropical Eco-geographical Process of Ministry of Education, School of Geographical Sciences, Fujian Normal University, Fuzhou, China; Fujian Sanming Forest Ecosystem National Observation and Research Station, Sanming, China; State Key Laboratory of Humid Subtropical Mountain Ecology, Fujian Normal University, Fuzhou, China
| | - Yusheng Yang
- Key Laboratory of Humid Subtropical Eco-geographical Process of Ministry of Education, School of Geographical Sciences, Fujian Normal University, Fuzhou, China; Fujian Sanming Forest Ecosystem National Observation and Research Station, Sanming, China; State Key Laboratory of Humid Subtropical Mountain Ecology, Fujian Normal University, Fuzhou, China
| | - Guangshui Chen
- Key Laboratory of Humid Subtropical Eco-geographical Process of Ministry of Education, School of Geographical Sciences, Fujian Normal University, Fuzhou, China; Fujian Sanming Forest Ecosystem National Observation and Research Station, Sanming, China; State Key Laboratory of Humid Subtropical Mountain Ecology, Fujian Normal University, Fuzhou, China.
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2
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Kearsley E, Verbeeck H, Stoffelen P, Janssens SB, Yakusu EK, Kosmala M, De Mil T, Bauters M, Kitima ER, Ndiapo JM, Chuda AL, Richardson AD, Wingate L, Ilondea BA, Beeckman H, van den Bulcke J, Boeckx P, Hufkens K. Historical tree phenology data reveal the seasonal rhythms of the Congo Basin rainforest. PLANT-ENVIRONMENT INTERACTIONS (HOBOKEN, N.J.) 2024; 5:e10136. [PMID: 38476212 PMCID: PMC10926959 DOI: 10.1002/pei3.10136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 01/05/2024] [Accepted: 01/23/2024] [Indexed: 03/14/2024]
Abstract
Tropical forest phenology directly affects regional carbon cycles, but the relation between species-specific and whole-canopy phenology remains largely uncharacterized. We present a unique analysis of historical tropical tree phenology collected in the central Congo Basin, before large-scale impacts of human-induced climate change. Ground-based long-term (1937-1956) phenological observations of 140 tropical tree species are recovered, species-specific phenological patterns analyzed and related to historical meteorological records, and scaled to characterize stand-level canopy dynamics. High phenological variability within and across species and in climate-phenology relationships is observed. The onset of leaf phenophases in deciduous species was triggered by drought and light availability for a subset of species and showed a species-specific decoupling in time along a bi-modal seasonality. The majority of the species remain evergreen, although central African forests experience relatively low rainfall. Annually a maximum of 1.5% of the canopy is in leaf senescence or leaf turnover, with overall phenological variability dominated by a few deciduous species, while substantial variability is attributed to asynchronous events of large and/or abundant trees. Our results underscore the importance of accounting for constituent signals in canopy-wide scaling and the interpretation of remotely sensed phenology signals.
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Affiliation(s)
- Elizabeth Kearsley
- Computational and Applied Vegetation Ecology Lab, Department of Environment, Faculty of Bioscience EngineeringGhent UniversityGentBelgium
- BlueGreen LabsMelseleBelgium
| | - Hans Verbeeck
- Computational and Applied Vegetation Ecology Lab, Department of Environment, Faculty of Bioscience EngineeringGhent UniversityGentBelgium
| | | | - Steven B. Janssens
- Meise Botanic GardenMeiseBelgium
- Department of Biology, Leuven Plant InstituteKULeuvenLeuvenBelgium
| | - Emmanuel Kasongo Yakusu
- UGent‐Woodlab (Laboratory of Wood Technology), Department of Environment, Faculty of Bioscience EngineeringGhent UniversityGentBelgium
- Service of Wood BiologyRoyal Museum for Central AfricaTervurenBelgium
- Faculté de gestion des ressources naturelles renouvelablesUniversité de KisanganiKisanganiDemocratic Republic of Congo
| | - Margaret Kosmala
- Department of Organismic and Evolutionary BiologyHarvard UniversityCambridgeMassachusettsUSA
- CIBO TechnologiesCambridgeMassachusettsUSA
| | - Tom De Mil
- Forest is Life, TERRA Teaching and Research Centre, Gembloux Agro Bio‐TechUniversity of LiègeGemblouxBelgium
| | - Marijn Bauters
- Isotope Bioscience Laboratory ‐ ISOFYS, Department of Green Chemistry and TechnologyGhent UniversityGentBelgium
- Research Group of Plants and Ecosystems (PLECO), Department of BiologyUniversity of AntwerpWilrijkBelgium
| | - Elasi Ramanzani Kitima
- Institut National pour l'Etude et la Recherche Agronomiques‐INERAYangambiDemocratic Republic of Congo
| | - José Mbifo Ndiapo
- Institut National pour l'Etude et la Recherche Agronomiques‐INERAYangambiDemocratic Republic of Congo
| | - Adelard Lonema Chuda
- Institut National pour l'Etude et la Recherche Agronomiques‐INERAYangambiDemocratic Republic of Congo
| | - Andrew D. Richardson
- Center for Ecosystem Science and SocietyNorthern Arizona UniversityFlagstaffArizonaUSA
- School of Informatics, Computing and Cyber SystemsNorthern Arizona UniversityFlagstaffArizonaUSA
| | | | - Bhély Angoboy Ilondea
- UGent‐Woodlab (Laboratory of Wood Technology), Department of Environment, Faculty of Bioscience EngineeringGhent UniversityGentBelgium
- Service of Wood BiologyRoyal Museum for Central AfricaTervurenBelgium
- Institut National pour l'Étude et la Recherche AgronomiquesKinshasaDemocratic Republic of Congo
| | - Hans Beeckman
- Service of Wood BiologyRoyal Museum for Central AfricaTervurenBelgium
| | - Jan van den Bulcke
- UGent‐Woodlab (Laboratory of Wood Technology), Department of Environment, Faculty of Bioscience EngineeringGhent UniversityGentBelgium
| | - Pascal Boeckx
- Isotope Bioscience Laboratory ‐ ISOFYS, Department of Green Chemistry and TechnologyGhent UniversityGentBelgium
| | - Koen Hufkens
- Computational and Applied Vegetation Ecology Lab, Department of Environment, Faculty of Bioscience EngineeringGhent UniversityGentBelgium
- BlueGreen LabsMelseleBelgium
- INRAE, UMR ISPAVillenave d'OrnonFrance
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3
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Lin S, Wang H, Dai J, Ge Q. Spring wood phenology responds more strongly to chilling temperatures than bud phenology in European conifers. TREE PHYSIOLOGY 2024; 44:tpad146. [PMID: 38079514 DOI: 10.1093/treephys/tpad146] [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: 08/02/2023] [Revised: 10/19/2023] [Accepted: 12/01/2023] [Indexed: 02/09/2024]
Abstract
A comparative assessment of bud and wood phenology could aid a better understanding of tree growth dynamics. However, the reason for asynchronism or synchronism in leaf and cambial phenology remains unclear. To test the assumption that the temporal relationship between the budburst date and the onset date of wood formation is due to their common or different responses to environmental factors, we constructed a wood phenology dataset from previous literature, and compared it with an existing bud phenology dataset in Europe. We selected three common conifers (Larix decidua Mill., Picea abies (L.) H. Karst. and Pinus sylvestris L.) in both datasets and analyzed 909 records of the onset of wood formation at 47 sites and 238,720 records of budburst date at 3051 sites. We quantified chilling accumulation (CA) and forcing requirement (FR) of budburst and onset of wood formation based on common measures of CA and FR. We then constructed negative exponential CA-FR curves for bud and wood phenology separately. The results showed that the median, variance and probability distribution of CA-FR curves varied significantly between bud and wood phenology for three conifers. The different FR under the same chilling condition caused asynchronous bud and wood phenology. Furthermore, the CA-FR curves manifested that wood phenology was more sensitive to chilling than bud phenology. Thus, the FR of the onset of wood formation increases more than that of budburst under the same warming scenarios, explaining the stronger earlier trends in the budburst date than the onset date of woody formation simulated by the process-based model. Our work not only provides a possible explanation for asynchronous bud and wood phenology from the perspective of organ-specific responses to chilling and forcing, but also develops a phenological model for predicting both bud and wood phenology with acceptable uncertainties.
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Affiliation(s)
- Shaozhi Lin
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 11A, Datun Road, Chaoyang District, Beijing 100101, China
- University of Chinese Academy of Sciences, 19A, Yuquan Road, Shijingshan District, Beijing 100049, China
| | - Huanjiong Wang
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 11A, Datun Road, Chaoyang District, Beijing 100101, China
| | - Junhu Dai
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 11A, Datun Road, Chaoyang District, Beijing 100101, China
- University of Chinese Academy of Sciences, 19A, Yuquan Road, Shijingshan District, Beijing 100049, China
- China-Pakistan Joint Research Center on Earth Sciences, Chinese Academy of Sciences - Higher Education Commission of Pakistan, Sector H-9, East Service Road, Islamabad 45320, Pakistan
| | - Quansheng Ge
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 11A, Datun Road, Chaoyang District, Beijing 100101, China
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Robinson D. OPT-ing out: Root-shoot dynamics are caused by local resource capture and biomass allocation, not optimal partitioning. PLANT, CELL & ENVIRONMENT 2023; 46:3023-3039. [PMID: 36285352 DOI: 10.1111/pce.14470] [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: 06/16/2022] [Revised: 10/11/2022] [Accepted: 10/20/2022] [Indexed: 06/16/2023]
Abstract
Combining plant growth analysis with a simple model of local resource capture and biomass allocation applied to exemplary experimental data, showed that dynamic changes in allocation to roots when nutrients are scarce is caused by disparities in growth rates between roots and shoots. Whole-plant growth rates also change but are not caused by an adaptive allocation response. Allocation and whole-plant growth rate are interdependent, not independent, traits. Following a switch in nutrient availability or partial biomass removal, convergence of allocation and growth rate trajectories does not reflect goal-seeking behaviour, but the constraints imposed by finite resource availability. Optimal root-shoot allocations are unnecessary to maximise whole-plant growth rate. Similar growth rates are attainable with different allocations. Changes in allocation cannot maintain or restore a superior whole-plant growth rate. Roots and shoots do not have to be tightly coordinated but can operate semiautonomously, as their modular construction permits. These findings question the plausibility of the prevailing general explanation of plants' root-shoot allocation responses, 'optimal partitioning theory' (OPT). Local allocation models, not OPT, explain the origins of variability in root-shoot trade-offs in individuals, the allocation of biomass at global and ecosystem scales and inform selection for allocation plasticity in crop breeding.
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Affiliation(s)
- David Robinson
- School of Biological Sciences, University of Aberdeen, Aberdeen, UK
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5
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Volaire F, Barkaoui K, Grémillet D, Charrier G, Dangles O, Lamarque LJ, Martin-StPaul N, Chuine I. Is a seasonally reduced growth potential a convergent strategy to survive drought and frost in plants? ANNALS OF BOTANY 2023; 131:245-254. [PMID: 36567631 PMCID: PMC9992932 DOI: 10.1093/aob/mcac153] [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: 04/29/2022] [Accepted: 12/14/2022] [Indexed: 06/17/2023]
Abstract
BACKGROUND Plants have adapted to survive seasonal life-threatening frost and drought. However, the timing and frequency of such events are impacted by climate change, jeopardizing plant survival. Understanding better the strategies of survival to dehydration stress is therefore timely and can be enhanced by the cross-fertilization of research between disciplines (ecology, physiology), models (woody, herbaceous species) and types of stress (drought, frost). SCOPE We build upon the 'growth-stress survival' trade-off, which underpins the identification of global plant strategies across environments along a 'fast-slow' economics spectrum. Although phenological adaptations such as dormancy are crucial to survive stress, plant global strategies along the fast-slow economic spectrum rarely integrate growth variations across seasons. We argue that the growth-stress survival trade-off can be a useful framework to identify convergent plant ecophysiological strategies to survive both frost and drought. We review evidence that reduced physiological activity, embolism resistance and dehydration tolerance of meristematic tissues are interdependent strategies that determine thresholds of mortality among plants under severe frost and drought. We show that complete dormancy, i.e. programmed growth cessation, before stress occurrence, minimizes water flows and maximizes dehydration tolerance during seasonal life-threatening stresses. We propose that incomplete dormancy, i.e. the programmed reduction of growth potential during the harshest seasons, could be an overlooked but major adaptation across plants. Quantifying stress survival in a range of non-dormant versus winter- or summer-dormant plants, should reveal to what extent incomplete to complete dormancy could represent a proxy for dehydration tolerance and stress survival. CONCLUSIONS Our review of the strategies involved in dehydration stress survival suggests that winter and summer dormancy are insufficiently acknowledged as plant ecological strategies. Incorporating a seasonal fast-slow economics spectrum into global plant strategies improves our understanding of plant resilience to seasonal stress and refines our prevision of plant adaptation to extreme climatic events.
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Affiliation(s)
- Florence Volaire
- CEFE, Université Montpellier, INRAE, CNRS, EPHE, IRD, F-34090 Montpellier, France
| | - Karim Barkaoui
- CIRAD, UMR ABSys, F-34398 Montpellier, France
- ABSys, Université F-34060 Montpellier, CIHEAM-IAMM, CIRAD, INRAE, Institut Agro, Montpellier, France
| | - David Grémillet
- CEFE, Université Montpellier, CNRS, EPHE, IRD, F-34090 Montpellier, France
- Percy FitzPatrick Institute of African Ornithology, University of Cape Town, Rondebosch, South Africa
| | - Guillaume Charrier
- Université Clermont Auvergne, INRAE, PIAF, F-63000 Clermont Ferrand, France
| | - Olivier Dangles
- CEFE, Université Montpellier, CNRS, EPHE, IRD, F-34090 Montpellier, France
| | - Laurent J Lamarque
- Département des Sciences de l’Environnement, Université du Québec à Trois-Rivières, Trois-Rivières, QC, G9A 5H7, Canada
| | - Nicolas Martin-StPaul
- INRAE, URFM, Domaine Saint Paul, Centre de recherche PACA, 228 route de l’Aérodrome, CS 40509, Domaine Saint-Paul, Site Agroparc, France
| | - Isabelle Chuine
- CEFE, Université Montpellier, CNRS, EPHE, IRD, F-34090 Montpellier, France
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6
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Li S, Dong S, Fu Y, Zhou B, Liu S, Shen H, Xu Y, Gao X, Xiao J, Wu S, Li F. Air or soil temperature matters the responses of alpine plants in biomass accumulation to climate warming. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 844:157141. [PMID: 35798113 DOI: 10.1016/j.scitotenv.2022.157141] [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: 05/27/2022] [Revised: 06/27/2022] [Accepted: 06/29/2022] [Indexed: 06/15/2023]
Abstract
Climate change has substantially affected plant phenology and growth on the Qinghai-Tibetan Plateau (QTP), while it remains unclear how plant phenology and growth impact the plant biomass under climate change. We used long-term data (from 1997 to 2017) for four plants, Stipa purpurea, Artemisia scoparia, Kobresia humilis and Astragalus laxmannii in the alpine meadow to examine the relationships among multiple climate factors, vegetative growth, reproductive growth, intrinsic growth rate and biomass. The order of returning to green determines the growth strategies of different plants, the earliest plants to green (p < 0.05) (e.g., Stipa purpurea and Artemisia scoparia) would choose the strategy of vegetative growth (p < 0.05); the earlier plants (p < 0.05) (e.g., Kobresia humilis) would be regulated by both vegetative growth and reproductive growth (p < 0.05); while the latest plant to green (p < 0.05) such as Astragalus laxmannii, would choose intrinsic growth rate rather than growing season (P < 0.05). Temperature was the most important drivers for key phenological phases and growth patterns of four species, different factors play a role in different stages of the growth period, i.e., in the early and late stage is the soil temperature, while in the middle stage is the average temperature or the maximum temperature, and all the optimum thresholds were >30 day. These findings provide the in-situ evidences of long-term changes in phenology and its associated growth on the biomass of alpine plants on the QTP in the era of climate change.
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Affiliation(s)
- Shuai Li
- College of Resource and Environment, Shanxi Agricultural University, Taigu 030801, China
| | - Shikui Dong
- School of Grassland Science, Beijing Forestry University, Beijing 100083, China.
| | - Yongshuo Fu
- College of Water Sciences, Beijing Normal University, Beijing 100875, China
| | - Bingrong Zhou
- Qinghai Institute of Meteorology Sciences, Xining 810001, China
| | - Shiliang Liu
- School of Environment, Beijing Normal University, Beijing 100875, China
| | - Hao Shen
- School of Grassland Science, Beijing Forestry University, Beijing 100083, China
| | - Yudan Xu
- College of Grassland Science, Shanxi Agricultural University, Taigu 030801, China
| | - Xiaoxia Gao
- School of Environment, Beijing Normal University, Beijing 100875, China
| | - Jiannan Xiao
- School of Environment, Beijing Normal University, Beijing 100875, China
| | - Shengnan Wu
- School of Grassland Science, Beijing Forestry University, Beijing 100083, China
| | - Fu Li
- Qinghai Institute of Meteorology Sciences, Xining 810001, China
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7
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Burdon RD, Bartlett MJ. Putative biotic drivers of plant phenology: With special reference to pathogens and deciduousness. Ecol Evol 2022; 12:e8932. [PMID: 35784056 PMCID: PMC9163672 DOI: 10.1002/ece3.8932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 04/15/2022] [Accepted: 04/19/2022] [Indexed: 11/24/2022] Open
Abstract
Plant phenology is not only manifested in the seasonal timing of vegetative and reproductive processes but also has ontogenetic aspects. The adaptive basis of seasonal phenology has been considered mainly in terms of climatic drivers. However, some biotic factors as likely evolutionary influences on plants’ phenology appear to have been under‐researched. Several specific cases of putative biotic factors driving plant phenology are outlined, involving both herbivores and pathogens. These illustrate the diversity of likely interactions rather than any systematic coverage or review. Emphasis is on woody perennials, in which phenology is often most multifaceted and complicated by the ontogenetic aspect. The complete seasonal leaf fall that characterizes deciduous plants may be a very important defense against some pathogens. Whether biotic influences drive acquisition or long‐term persistence of deciduousness is considered. In one case, of leaf rusts in poplars, countervailing influences of the rusts and climate suggest persistence. Often, however, biotic and environmental influences likely reinforce each other. The timing and duration of shoot flushing may in at least some cases contribute to defenses against herbivores, largely through brief periods of “predator satiation” when plant tissues have highest food value. Wide re‐examination of plant phenology, accommodating the roles of biotic factors and their interplays with environments as additional adaptive drivers, is advocated toward developing and applying hypotheses that are observationally or experimentally testable.
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Affiliation(s)
- Rowland D. Burdon
- Scion (New Zealand Forest Research Institute Ltd) Rotorua New Zealand
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8
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Menezes J, Garcia S, Grandis A, Nascimento H, Domingues TF, Guedes AV, Aleixo I, Camargo P, Campos J, Damasceno A, Dias-Silva R, Fleischer K, Kruijt B, Cordeiro AL, Martins NP, Meir P, Norby RJ, Pereira I, Portela B, Rammig A, Ribeiro AG, Lapola DM, Quesada CA. Changes in leaf functional traits with leaf age: when do leaves decrease their photosynthetic capacity in Amazonian trees? TREE PHYSIOLOGY 2022; 42:922-938. [PMID: 33907798 DOI: 10.1093/treephys/tpab042] [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: 04/24/2020] [Revised: 09/22/2020] [Accepted: 03/30/2021] [Indexed: 06/12/2023]
Abstract
Most leaf functional trait studies in the Amazon basin do not consider ontogenetic variations (leaf age), which may influence ecosystem productivity throughout the year. When leaf age is taken into account, it is generally considered discontinuous, and leaves are classified into age categories based on qualitative observations. Here, we quantified age-dependent changes in leaf functional traits such as the maximum carboxylation rate of ribulose-1,5-biphosphate carboxylase/oxygenase (Rubisco) (Vcmax), stomatal control (Cgs%), leaf dry mass per area and leaf macronutrient concentrations for nine naturally growing Amazon tropical trees with variable phenological strategies. Leaf ages were assessed by monthly censuses of branch-level leaf demography; we also performed leaf trait measurements accounting for leaf chronological age based on days elapsed since the first inclusion in the leaf demography, not predetermined age classes. At the tree community scale, a nonlinear relationship between Vcmax and leaf age existed: young, developing leaves showed the lowest mean photosynthetic capacity, increasing to a maximum at 45 days and then decreasing gradually with age in both continuous and categorical age group analyses. Maturation times among species and phenological habits differed substantially, from 8 ± 30 to 238 ± 30 days, and the rate of decline of Vcmax varied from -0.003 to -0.065 μmol CO2 m-2 s-1 day-1. Stomatal control increased significantly in young leaves but remained constant after peaking. Mass-based phosphorus and potassium concentrations displayed negative relationships with leaf age, whereas nitrogen did not vary temporally. Differences in life strategies, leaf nutrient concentrations and phenological types, not the leaf age effect alone, may thus be important factors for understanding observed photosynthesis seasonality in Amazonian forests. Furthermore, assigning leaf age categories in diverse tree communities may not be the recommended method for studying carbon uptake seasonality in the Amazon, since the relationship between Vcmax and leaf age could not be confirmed for all trees.
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Affiliation(s)
- Juliane Menezes
- Tropical Forest Sciences Graduate Program, National Institute of Amazonian Research (INPA), Manaus, Amazonas, Brazil
| | - Sabrina Garcia
- Laboratory of Biogeochemical Sciences, National Institute of Amazonian Research (INPA), Manaus, Amazonas 69067-375, Brazil
| | - Adriana Grandis
- Laboratory of Physiology and Ecology of Plants (Lafieco), Department of Botany, Biosciences Institute, University of Sao Paulo, Sao Paulo 05508-090, Brazil
| | - Henrique Nascimento
- Biodiversity Coordination (CBIO), National Institute of Amazonian Research (INPA), Manaus, Amazonas 69067-375, Brazil
| | - Tomas F Domingues
- Department of Biology-FFCLRP, University of Sao Paulo, Ribeirao Preto, Sao Paulo 14040-901, Brazil
| | - Alacimar V Guedes
- Forestry and Environmental Sciences Graduate Program (PPGCIFA), Federal University of Amazonas, Manaus, Amazonas 69067-005, Brazil
| | - Izabela Aleixo
- Laboratory of Biogeochemical Sciences, National Institute of Amazonian Research (INPA), Manaus, Amazonas 69067-375, Brazil
| | - Plínio Camargo
- Isotopic Ecology Laboratory of the Center for Nuclear Energy in Agriculture (CENA), University of Sao Paulo, Piracicaba, Sao Paulo 13416-000, Brazil
| | - Jéssica Campos
- Tropical Forest Sciences Graduate Program, National Institute of Amazonian Research (INPA), Manaus, Amazonas, Brazil
| | - Amanda Damasceno
- Ecology Graduate Program, National Institute of Amazonian Research, Manaus, Amazonas 69067-375, Brazil
| | - Renann Dias-Silva
- Zoology Graduate Program, Federal University of Amazonas, Manaus, Amazonas 69067-005, Brazil
| | - Katrin Fleischer
- School of Life Sciences, Technical University of Munich, Freising 85354, Germany
| | - Bart Kruijt
- Wageningen University & Research, 6700 AA PO Box 47 PB Wageningen, Netherlands
| | - Amanda L Cordeiro
- Tropical Forest Sciences Graduate Program, National Institute of Amazonian Research (INPA), Manaus, Amazonas, Brazil
- Department of Ecosystem Science and Sustainability, Warner College of Natural Resources, Colorado State University, Fort Collins, Colorado 80523-1476
| | - Nathielly P Martins
- Tropical Forest Sciences Graduate Program, National Institute of Amazonian Research (INPA), Manaus, Amazonas, Brazil
| | - Patrick Meir
- Research School of Biology, Australian National University (ANU), Canberra 2601, Australia
- School of Geosciences, University of Edinburgh, Edinburgh EH9 3FF, UK
| | - Richard J Norby
- Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Iokanam Pereira
- Tropical Forest Sciences Graduate Program, National Institute of Amazonian Research (INPA), Manaus, Amazonas, Brazil
| | - Bruno Portela
- Laboratory of Biogeochemical Sciences, National Institute of Amazonian Research (INPA), Manaus, Amazonas 69067-375, Brazil
| | - Anja Rammig
- School of Life Sciences, Technical University of Munich, Freising 85354, Germany
| | - Ana Gracy Ribeiro
- Tropical Forest Sciences Graduate Program, National Institute of Amazonian Research (INPA), Manaus, Amazonas, Brazil
| | - David M Lapola
- Center for Meteorological and Climatic Research Applied to Agriculture (CEPAGRI), University of Campinas, Campinas, Sao Paulo 13083-886, Brazil
| | - Carlos A Quesada
- Environmental Dynamics Coordination (CDAM), National Institute of Amazonian Research (INPA), Manaus, Amazonas 69067-375, Brazil
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Gallup SM, Baker IT, Gallup JL, Restrepo‐Coupe N, Haynes KD, Geyer NM, Denning AS. Accurate Simulation of Both Sensitivity and Variability for Amazonian Photosynthesis: Is It Too Much to Ask? JOURNAL OF ADVANCES IN MODELING EARTH SYSTEMS 2021; 13:e2021MS002555. [PMID: 34594478 PMCID: PMC8459247 DOI: 10.1029/2021ms002555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 07/22/2021] [Accepted: 07/28/2021] [Indexed: 06/13/2023]
Abstract
Estimates of Amazon rainforest gross primary productivity (GPP) differ by a factor of 2 across a suite of three statistical and 18 process models. This wide spread contributes uncertainty to predictions of future climate. We compare the mean and variance of GPP from these models to that of GPP at six eddy covariance (EC) towers. Only one model's mean GPP across all sites falls within a 99% confidence interval for EC GPP, and only one model matches EC variance. The strength of model response to climate drivers is related to model ability to match the seasonal pattern of the EC GPP. Models with stronger seasonal swings in GPP have stronger responses to rain, light, and temperature than does EC GPP. The model to data comparison illustrates a trade-off inherent to deterministic models between accurate simulation of a mean (average) and accurate responsiveness to drivers. The trade-off exists because all deterministic models simplify processes and lack at least some consequential driver or interaction. If a model's sensitivities to included drivers and their interactions are accurate, then deterministically predicted outcomes have less variability than is realistic. If a GPP model has stronger responses to climate drivers than found in data, model predictions may match the observed variance and seasonal pattern but are likely to overpredict GPP response to climate change. High or realistic variability of model estimates relative to reference data indicate that the model is hypersensitive to one or more drivers.
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Affiliation(s)
- Sarah M. Gallup
- Graduate Degree Program in EcologyColorado State UniversityFort CollinsCOUSA
| | - Ian T. Baker
- Department of Atmospheric ScienceColorado State UniversityFort CollinsCOUSA
| | - John L. Gallup
- Department of EconomicsPortland State UniversityPortlandORUSA
| | - Natalia Restrepo‐Coupe
- Department of Ecology and Evolutionary BiologyUniversity of ArizonaTucsonAZUSA
- School of Life SciencesUniversity of Technology SydneyUltimoNSWAustralia
| | | | - Nicholas M. Geyer
- Department of Atmospheric ScienceColorado State UniversityFort CollinsCOUSA
| | - A. Scott Denning
- Graduate Degree Program in EcologyColorado State UniversityFort CollinsCOUSA
- Department of Atmospheric ScienceColorado State UniversityFort CollinsCOUSA
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Lirette AO, Despland E. Defensive Traits during White Spruce ( Picea glauca) Leaf Ontogeny. INSECTS 2021; 12:insects12070644. [PMID: 34357304 PMCID: PMC8306798 DOI: 10.3390/insects12070644] [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: 06/12/2021] [Revised: 07/05/2021] [Accepted: 07/11/2021] [Indexed: 11/23/2022]
Abstract
Simple Summary Leaves can only toughen after they have finished growing and, as a result, many herbivorous insects specialize in newly developing leaves because softer leaves are easier to chew. The foliage of conifer trees is particularly tough, and so one would expect conifers to invest more defensive chemicals into soft vulnerable growing needles than into tough mature ones. We summarize the literature describing how chemical defenses of foliage change during the growing season in white spruce, an economically important conifer tree. We next report measurements of the toughness of white spruce buds as they swell, burst, and grow into young needles. As expected, buds soften as they swell in spring, but after budburst, needles become tougher until they are similar to previous-year foliage in mid-summer. Leaves grown in the sun are slightly tougher than leaves grown in the shade. However, there was no indication that trees invest more in chemical defense of growing leaves than of mature leaves. Abstract Changes during leaf ontogeny affect palatability to herbivores, such that many insects, including the eastern spruce budworm (Choristoneura fumiferana (Clem.)), are specialist feeders on growing conifer leaves and buds. Developmental constraints imply lower toughness in developing foliage, and optimal defense theory predicts higher investment in chemical defense in these vulnerable yet valuable developing leaves. We summarize the literature on the time course of defensive compounds in developing white spruce (Picea glauca (Moench) Voss) needles and report original research findings on the ontogeny of white spruce needle toughness. Our results show the predicted pattern of buds decreasing in toughness followed by leaves increasing in toughness during expansion, accompanied by opposite trends in water content. Toughness of mature foliage decreased slightly during the growing season, with no significant relationship with water content. Toughness of sun-grown leaves was slightly higher than that of shade-grown leaves. However, the literature review did not support the expected pattern of higher defensive compounds in expanding leaves than in mature leaves, suggesting that white spruce might instead exhibit a fast-growth low-defense strategy.
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Abstract
Spatial and temporal patterns of tropical leaf renewal are poorly understood and poorly parameterized in modern Earth System Models due to lack of data. Remote sensing has great potential for sampling leaf phenology across tropical landscapes but until now has been impeded by lack of ground-truthing, cloudiness, poor spatial resolution, and the cryptic nature of incremental leaf turnover in many tropical plants. To our knowledge, satellite data have never been used to monitor individual crown leaf phenology in the tropics, an innovation that would be a major breakthrough for individual and species-level ecology and improve climate change predictions for the tropics. In this paper, we assessed whether satellite data can detect leaf turnover for individual trees using ground observations of a candidate tropical tree species, Moabi (Baillonella toxisperma), which has a mega-crown visible from space. We identified and delineated Moabi crowns at Lopé NP, Gabon from satellite imagery using ground coordinates and extracted high spatial and temporal resolution, optical, and synthetic-aperture radar (SAR) timeseries data for each tree. We normalized these data relative to the surrounding forest canopy and combined them with concurrent monthly crown observations of new, mature, and senescent leaves recorded from the ground. We analyzed the relationship between satellite and ground observations using generalized linear mixed models (GLMMs). Ground observations of leaf turnover were significantly correlated with optical indices derived from Sentinel-2 optical data (the normalized difference vegetation index and the green leaf index), but not with SAR data derived from Sentinel-1. We demonstrate, perhaps for the first time, how the leaf phenology of individual large-canopied tropical trees can directly influence the spectral signature of satellite pixels through time. Additionally, while the level of uncertainty in our model predictions is still very high, we believe this study shows that we are near the threshold for orbital monitoring of individual crowns within tropical forests, even in challenging locations, such as cloudy Gabon. Further technical advances in remote sensing instruments into the spatial and temporal scales relevant to organismal biological processes will unlock great potential to improve our understanding of the Earth system.
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