1
|
Wilkening JV, Feng X, Dawson TE, Thompson SE. Different roads, same destination: The shared future of plant ecophysiology and ecohydrology. PLANT, CELL & ENVIRONMENT 2024; 47:3447-3465. [PMID: 38725360 DOI: 10.1111/pce.14937] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 04/13/2024] [Accepted: 04/23/2024] [Indexed: 08/16/2024]
Abstract
Terrestrial water fluxes are substantially mediated by vegetation, while the distribution, growth, health, and mortality of plants are strongly influenced by the availability of water. These interactions, playing out across multiple spatial and temporal scales, link the disciplines of plant ecophysiology and ecohydrology. Despite this connection, the disciplines have provided complementary, but largely independent, perspectives on the soil-plant-atmosphere continuum since their crystallization as modern scientific disciplines in the late 20th century. This review traces the development of the two disciplines, from their respective origins in engineering and ecology, their largely independent growth and maturation, and the eventual development of common conceptual and quantitative frameworks. This common ground has allowed explicit coupling of the disciplines to better understand plant function. Case studies both illuminate the limitations of the disciplines working in isolation, and reveal the exciting possibilities created by consilience between the disciplines. The histories of the two disciplines suggest opportunities for new advances will arise from sharing methodologies, working across multiple levels of complexity, and leveraging new observational technologies. Practically, these exchanges can be supported by creating shared scientific spaces. This review argues that consilience and collaboration are essential for robust and evidence-based predictions and policy responses under global change.
Collapse
Affiliation(s)
- Jean V Wilkening
- Civil, Environmental, and Geo- Engineering, University of Minnesota, Minneapolis, Minnesota, USA
- St. Anthony Falls Laboratory, University of Minnesota, Minneapolis, Minnesota, USA
| | - Xue Feng
- Civil, Environmental, and Geo- Engineering, University of Minnesota, Minneapolis, Minnesota, USA
- St. Anthony Falls Laboratory, University of Minnesota, Minneapolis, Minnesota, USA
| | - Todd E Dawson
- Integrative Biology, University of California, Berkeley, California, USA
- Environmental Science, Policy, and Management, University of California, Berkeley, California, USA
| | - Sally E Thompson
- Civil, Environmental, and Mining Engineering, University of Western Australia, Perth, Western Australia, Australia
- Centre for Water and Spatial Science, University of Western Australia, Perth, Western Australia, Australia
| |
Collapse
|
2
|
Sterck FJ, Song Y, Poorter L. Drought- and heat-induced mortality of conifer trees is explained by leaf and growth legacies. SCIENCE ADVANCES 2024; 10:eadl4800. [PMID: 38608026 PMCID: PMC11014445 DOI: 10.1126/sciadv.adl4800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Accepted: 03/08/2024] [Indexed: 04/14/2024]
Abstract
An increased frequency and severity of droughts and heat waves have resulted in increased tree mortality and forest dieback across the world, but underlying mechanisms are poorly understood. We used a common garden experiment with 20 conifer tree species to quantify mortality after three consecutive hot, dry summers and tested whether mortality could be explained by putative underlying mechanisms, such as stem hydraulics and legacies affected by leaf life span and stem growth responses to previous droughts. Mortality varied from 0 to 79% across species and was not affected by hydraulic traits. Mortality increased with species' leaf life span probably because leaf damage caused crown dieback and contributed to carbon depletion and bark beetle damage. Mortality also increased with lower growth resilience, which may exacerbate the contribution of carbon depletion and bark beetle sensitivity to tree mortality. Our study highlights how ecological legacies at different time scales can explain tree mortality in response to hot, dry periods and climate change.
Collapse
Affiliation(s)
- Frank J. Sterck
- Forest Ecology and Forest Management Group, Wageningen University and Research, P.O. Box 47, 6700 AA Wageningen, Netherlands
| | - Yanjun Song
- Forest Ecology and Forest Management Group, Wageningen University and Research, P.O. Box 47, 6700 AA Wageningen, Netherlands
- School of Biological Sciences, Washington State University, P.O. Box 644236, Pullman, WA 99164-4236, USA
| | - Lourens Poorter
- Forest Ecology and Forest Management Group, Wageningen University and Research, P.O. Box 47, 6700 AA Wageningen, Netherlands
| |
Collapse
|
3
|
Torres-Ruiz JM, Cochard H, Delzon S, Boivin T, Burlett R, Cailleret M, Corso D, Delmas CEL, De Caceres M, Diaz-Espejo A, Fernández-Conradi P, Guillemot J, Lamarque LJ, Limousin JM, Mantova M, Mencuccini M, Morin X, Pimont F, De Dios VR, Ruffault J, Trueba S, Martin-StPaul NK. Plant hydraulics at the heart of plant, crops and ecosystem functions in the face of climate change. THE NEW PHYTOLOGIST 2024; 241:984-999. [PMID: 38098153 DOI: 10.1111/nph.19463] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 11/05/2023] [Indexed: 01/12/2024]
Abstract
Plant hydraulics is crucial for assessing the plants' capacity to extract and transport water from the soil up to their aerial organs. Along with their capacity to exchange water between plant compartments and regulate evaporation, hydraulic properties determine plant water relations, water status and susceptibility to pathogen attacks. Consequently, any variation in the hydraulic characteristics of plants is likely to significantly impact various mechanisms and processes related to plant growth, survival and production, as well as the risk of biotic attacks and forest fire behaviour. However, the integration of hydraulic traits into disciplines such as plant pathology, entomology, fire ecology or agriculture can be significantly improved. This review examines how plant hydraulics can provide new insights into our understanding of these processes, including modelling processes of vegetation dynamics, illuminating numerous perspectives for assessing the consequences of climate change on forest and agronomic systems, and addressing unanswered questions across multiple areas of knowledge.
Collapse
Affiliation(s)
- José M Torres-Ruiz
- Université Clermont-Auvergne, INRAE, PIAF, 63000, Clermont-Ferrand, France
| | - Hervé Cochard
- Université Clermont-Auvergne, INRAE, PIAF, 63000, Clermont-Ferrand, France
| | - Sylvain Delzon
- University of Bordeaux, INRAE, UMR BIOGECO, Pessac, 33615, France
| | | | - Regis Burlett
- University of Bordeaux, INRAE, UMR BIOGECO, Pessac, 33615, France
| | - Maxime Cailleret
- INRAE, Aix-Marseille Université, UMR RECOVER, Aix-en-Provence, 13100, France
| | - Déborah Corso
- University of Bordeaux, INRAE, UMR BIOGECO, Pessac, 33615, France
| | - Chloé E L Delmas
- INRAE, Bordeaux Sciences Agro, ISVV, SAVE, F-33140, Villenave d'Ornon, France
| | | | - Antonio Diaz-Espejo
- Instituto de Recursos Naturales y Agrobiología (IRNAS), Consejo Superior de Investigaciones Científicas (CSIC), Seville, 41012, Spain
| | | | - Joannes Guillemot
- CIRAD, UMR Eco&Sols, Montpellier, 34394, France
- Eco&Sols, Univ. Montpellier, CIRAD, INRAe, Institut Agro, IRD, Montpellier, 34394, France
- Department of Forest Sciences, ESALQ, University of São Paulo, Piracicaba, 05508-060, São Paulo, Brazil
| | - Laurent J Lamarque
- Département des sciences de l'environnement, Université du Québec à Trois-Rivières, Trois-Rivières, G9A 5H7, Québec, Canada
| | | | - Marylou Mantova
- Agronomy Department, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, 32611, USA
| | - Maurizio Mencuccini
- CREAF, Bellaterra (Cerdanyola del Vallès), Catalonia, E08193, Spain
- ICREA, Barcelona, 08010, Spain
| | - Xavier Morin
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, 34394, France
| | | | - Victor Resco De Dios
- Department of Forest and Agricultural Science and Engineering, University of Lleida, Lleida, 25198, Spain
- JRU CTFC-AGROTECNIO-CERCA Center, Lleida, 25198, Spain
| | | | - Santiago Trueba
- University of Bordeaux, INRAE, UMR BIOGECO, Pessac, 33615, France
| | | |
Collapse
|
4
|
Sanchez-Martinez P, Mencuccini M, García-Valdés R, Hammond WM, Serra-Diaz JM, Guo WY, Segovia RA, Dexter KG, Svenning JC, Allen C, Martínez-Vilalta J. Increased hydraulic risk in assemblages of woody plant species predicts spatial patterns of drought-induced mortality. Nat Ecol Evol 2023; 7:1620-1632. [PMID: 37640766 PMCID: PMC10555820 DOI: 10.1038/s41559-023-02180-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 07/26/2023] [Indexed: 08/31/2023]
Abstract
Predicting drought-induced mortality (DIM) of woody plants remains a key research challenge under climate change. Here, we integrate information on the edaphoclimatic niches, phylogeny and hydraulic traits of species to model the hydraulic risk of woody plants globally. We combine these models with species distribution records to estimate the hydraulic risk faced by local woody plant species assemblages. Thus, we produce global maps of hydraulic risk and test for its relationship with observed DIM. Our results show that local assemblages modelled as having higher hydraulic risk present a higher probability of DIM. Metrics characterizing this hydraulic risk improve DIM predictions globally, relative to models accounting only for edaphoclimatic predictors or broad functional groupings. The methodology we present here allows mapping of functional trait distributions and elucidation of global macro-evolutionary and biogeographical patterns, improving our ability to predict potential global change impacts on vegetation.
Collapse
Affiliation(s)
- Pablo Sanchez-Martinez
- Universitat Autònoma de Barcelona, Cerdanyola del Valles, Barcelona, Spain.
- CREAF, Cerdanyola del Valles, Barcelona, Spain.
- School of GeoSciences, University of Edinburgh, Edinburgh, UK.
| | | | - Raúl García-Valdés
- CREAF, Cerdanyola del Valles, Barcelona, Spain
- Department of Biology and Geology, Physics and Inorganic Chemistry, Rey Juan Carlos University, Móstoles, Madrid, Spain
| | | | - Josep M Serra-Diaz
- Université de Lorraine, AgroParisTech, INRAE, Nancy, France
- Eversource Energy Center, University of Connecticut, Storrs, CT, USA
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, USA
| | - Wen-Yong Guo
- Research Center for Global Change and Complex Ecosystems & Zhejiang Tiantong Forest Ecosystem National Observation and Research Station, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, P. R. China
- Department of Biology, Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) & Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Aarhus University, Aarhus C, Denmark
| | - Ricardo A Segovia
- Institute of Ecology and Biodiversity (IEB), Santiago, Chile
- Departamento de Botánica, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción, Chile
| | - Kyle G Dexter
- School of GeoSciences, University of Edinburgh, Edinburgh, UK
- Royal Botanic Garden Edinburgh, Edinburgh, UK
| | - Jens-Christian Svenning
- Department of Biology, Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) & Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Aarhus University, Aarhus C, Denmark
| | - Craig Allen
- Department of Geography and Environmental Studies, University of New Mexico, Albuquerque, NM, USA
| | - Jordi Martínez-Vilalta
- Universitat Autònoma de Barcelona, Cerdanyola del Valles, Barcelona, Spain
- CREAF, Cerdanyola del Valles, Barcelona, Spain
| |
Collapse
|
5
|
Martínez-Vilalta J, García-Valdés R, Jump A, Vilà-Cabrera A, Mencuccini M. Accounting for trait variability and coordination in predictions of drought-induced range shifts in woody plants. THE NEW PHYTOLOGIST 2023; 240:23-40. [PMID: 37501525 DOI: 10.1111/nph.19138] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 06/20/2023] [Indexed: 07/29/2023]
Abstract
Functional traits offer a promising avenue to improve predictions of species range shifts under climate change, which will entail warmer and often drier conditions. Although the conceptual foundation linking traits with plant performance and range shifts appears solid, the predictive ability of individual traits remains generally low. In this review, we address this apparent paradox, emphasizing examples of woody plants and traits associated with drought responses at the species' rear edge. Low predictive ability reflects the fact not only that range dynamics tend to be complex and multifactorial, as well as uncertainty in the identification of relevant traits and limited data availability, but also that trait effects are scale- and context-dependent. The latter results from the complex interactions among traits (e.g. compensatory effects) and between them and the environment (e.g. exposure), which ultimately determine persistence and colonization capacity. To confront this complexity, a more balanced coverage of the main functional dimensions involved (stress tolerance, resource use, regeneration and dispersal) is needed, and modelling approaches must be developed that explicitly account for: trait coordination in a hierarchical context; trait variability in space and time and its relationship with exposure; and the effect of biotic interactions in an ecological community context.
Collapse
Affiliation(s)
- Jordi Martínez-Vilalta
- CREAF, E08193, Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
- Universitat Autònoma de Barcelona, E08193, Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
| | - Raúl García-Valdés
- CREAF, E08193, Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
- Forest Science and Technology Centre of Catalonia (CTFC), E25280, Solsona, Spain
- Department of Biology, Geology, Physics and Inorganic Chemistry, School of Experimental Sciences and Technology, Rey Juan Carlos University, E28933, Móstoles, Madrid, Spain
| | - Alistair Jump
- Biological and Environmental Sciences, University of Stirling, FK9 4LA, Stirling, UK
| | - Albert Vilà-Cabrera
- CREAF, E08193, Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
- Biological and Environmental Sciences, University of Stirling, FK9 4LA, Stirling, UK
| | - Maurizio Mencuccini
- CREAF, E08193, Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
- ICREA, Pg. Lluís Companys 23, E08010, Barcelona, Spain
| |
Collapse
|
6
|
Yao Y, Ciais P, Viovy N, Joetzjer E, Chave J. How drought events during the last century have impacted biomass carbon in Amazonian rainforests. GLOBAL CHANGE BIOLOGY 2023; 29:747-762. [PMID: 36285645 PMCID: PMC10100251 DOI: 10.1111/gcb.16504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 09/27/2022] [Indexed: 06/16/2023]
Abstract
During the last two decades, inventory data show that droughts have reduced biomass carbon sink of the Amazon forest by causing mortality to exceed growth. However, process-based models have struggled to include drought-induced responses of growth and mortality and have not been evaluated against plot data. A process-based model, ORCHIDEE-CAN-NHA, including forest demography with tree cohorts, plant hydraulic architecture and drought-induced tree mortality, was applied over Amazonia rainforests forced by gridded climate fields and rising CO2 from 1901 to 2019. The model reproduced the decelerating signal of net carbon sink and drought sensitivity of aboveground biomass (AGB) growth and mortality observed at forest plots across selected Amazon intact forests for 2005 and 2010. We predicted a larger mortality rate and a more negative sensitivity of the net carbon sink during the 2015/16 El Niño compared with the former droughts. 2015/16 was indeed the most severe drought since 1901 regarding both AGB loss and area experiencing a severe carbon loss. We found that even if climate change did increase mortality, elevated CO2 contributed to balance the biomass mortality, since CO2 -induced stomatal closure reduces transpiration, thus, offsets increased transpiration from CO2 -induced higher foliage area.
Collapse
Affiliation(s)
- Yitong Yao
- Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA‐CNRS‐UVSQUniversité Paris‐SaclayGif‐sur‐YvetteFrance
| | - Philippe Ciais
- Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA‐CNRS‐UVSQUniversité Paris‐SaclayGif‐sur‐YvetteFrance
| | - Nicolas Viovy
- Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA‐CNRS‐UVSQUniversité Paris‐SaclayGif‐sur‐YvetteFrance
| | - Emilie Joetzjer
- INRAE, Universite de Lorraine, AgroParisTech, UMR SilvaNancyFrance
| | - Jerome Chave
- Laboratoire Evolution et Diversité Biologique UMR 5174 CNRS, IRDUniversité Paul SabatierToulouseFrance
| |
Collapse
|
7
|
Chen Z, Li S, Wan X, Liu S. Strategies of tree species to adapt to drought from leaf stomatal regulation and stem embolism resistance to root properties. FRONTIERS IN PLANT SCIENCE 2022; 13:926535. [PMID: 36237513 PMCID: PMC9552884 DOI: 10.3389/fpls.2022.926535] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 09/12/2022] [Indexed: 06/16/2023]
Abstract
Considerable evidences highlight the occurrence of increasing widespread tree mortality as a result of global climate change-associated droughts. However, knowledge about the mechanisms underlying divergent strategies of various tree species to adapt to drought has remained remarkably insufficient. Leaf stomatal regulation and embolism resistance of stem xylem serves as two important strategies for tree species to prevent hydraulic failure and carbon starvation, as comprising interconnected physiological mechanisms underlying drought-induced tree mortality. Hence, the physiological and anatomical determinants of leaf stomatal regulation and stems xylem embolism resistance are evaluated and discussed. In addition, root properties related to drought tolerance are also reviewed. Species with greater investment in leaves and stems tend to maintain stomatal opening and resist stem embolism under drought conditions. The coordination between stomatal regulation and stem embolism resistance are summarized and discussed. Previous studies showed that hydraulic safety margin (HSM, the difference between minimum water potential and that causing xylem dysfunction) is a significant predictor of tree species mortality under drought conditions. Compared with HSM, stomatal safety margin (the difference between water potential at stomatal closure and that causing xylem dysfunction) more directly merge stomatal regulation strategies with xylem hydraulic strategies, illustrating a comprehensive framework to characterize plant response to drought. A combination of plant traits reflecting species' response and adaptation to drought should be established in the future, and we propose four specific urgent issues as future research priorities.
Collapse
Affiliation(s)
- Zhicheng Chen
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China
| | - Shan Li
- Department of Environmental Science and Ecology, School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi’an, China
| | - Xianchong Wan
- Institute of Ecological Conservation and Restoration, Chinese Academy of Forestry, Beijing, China
| | - Shirong Liu
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China
| |
Collapse
|
8
|
Morcillo L, Muñoz-Rengifo JC, Torres-Ruiz JM, Delzon S, Moutahir H, Vilagrosa A. Post-drought conditions and hydraulic dysfunction determine tree resilience and mortality across Mediterranean Aleppo pine (Pinus halepensis) populations after an extreme drought event. TREE PHYSIOLOGY 2022; 42:1364-1376. [PMID: 35038335 DOI: 10.1093/treephys/tpac001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 01/11/2022] [Indexed: 06/14/2023]
Abstract
Drought-related tree mortality is a global phenomenon that currently affects a wide range of forests. Key functional variables on plant hydraulics, carbon economy, growth and allocation have been identified and play a role in tree drought responses. However, tree mortality thresholds based on such variables are difficult to identify, especially under field conditions. We studied several Aleppo pine populations differently affected by an extreme drought event in 2014, with mortality rates ranging from no mortality to 90% in the most severely affected population. We hypothesized that mortality is linked with high levels of xylem embolism, i.e., hydraulic dysfunction, which would also lead to lower tree resistance to drought in subsequent years. Despite not finding any differences among populations in the vulnerability curves to xylem embolism, there were large differences in the hydraulic safety margin (HSM) and the hydraulic dysfunction level. High mortality rates were associated with a negative HSM when xylem embolism reached values over 60%. We also found forest weakening and post-drought mortality related to a low hydraulic water transport capacity, reduced plant growth, low carbohydrate contents and high pest infestation rates. Our results highlight the importance of drought severity and the hydraulic dysfunction level on pine mortality, as well as post-drought conditions during recovery processes.
Collapse
Affiliation(s)
- L Morcillo
- Mediterranean Center for Environmental Studies (CEAM Foundation), Joint Research Unit University of Alicante-CEAM, University of Alicante, Alicante 03690, Spain
| | - J C Muñoz-Rengifo
- Department of Ecology, University of Alicante, Alicante 03690, Spain
- Department of Earth Science, Universidad Estatal Amazónica, Pastaza 160150, Ecuador
| | - J M Torres-Ruiz
- Université Clermont-Auvergne, INRAE, PIAF, Clermont-Ferrand 63000, France
| | - S Delzon
- Université Bordeaux, INRAE, BIOGECO, Pessac 33615, France
| | - H Moutahir
- Mediterranean Center for Environmental Studies (CEAM Foundation), Joint Research Unit University of Alicante-CEAM, University of Alicante, Alicante 03690, Spain
| | - A Vilagrosa
- Mediterranean Center for Environmental Studies (CEAM Foundation), Joint Research Unit University of Alicante-CEAM, University of Alicante, Alicante 03690, Spain
- Department of Ecology, University of Alicante, Alicante 03690, Spain
| |
Collapse
|
9
|
Detto M, Pacala SW. Plant hydraulics, stomatal control, and the response of a tropical forest to water stress over multiple temporal scales. GLOBAL CHANGE BIOLOGY 2022; 28:4359-4376. [PMID: 35373899 DOI: 10.1111/gcb.16179] [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: 10/14/2021] [Accepted: 03/21/2022] [Indexed: 06/14/2023]
Abstract
Many tropical regions are experiencing an intensification of drought, with increasing severity and frequency. The ecosystem response to these changes is still highly uncertain. On short time scales (from diurnal to seasonal), tropical forests respond to water stress by physiological controls, such as stomatal regulation and phenological adjustment, to cope with increasing atmospheric water demand and reduced water supply. However, the interactions among biological processes and co-varying environmental factors that determine the ecosystem-level fluxes are still unclear. Furthermore, climate variability at longer time scales, such as that generated by ENSO, produces less predictable effects because it depends on a highly stochastic combination of factors that might vary among forests and even between events in the same forest. This study will present some emerging patterns of response to water stress from 5 years of water, carbon, and energy fluxes observed on a seasonal tropical forest in central Panama, including an increase in productivity during the 2015 El Niño. These responses depend on the combination of environmental factors experienced by the forest throughout the seasonal cycle, in particular, increase in solar radiation, stimulating productivity, and increasing vapor pressure deficit (VPD) and decreasing soil moisture, limiting stomata opening. These results suggest a critical role of plant hydraulics in mediating the response to water stress over a broad range of temporal scales (diurnal, intraseasonal, seasonal, and interannual), by acclimating canopy conductance to light and VPD during different soil moisture regimes. A multilayer photosynthesis model coupled with a plant hydraulics scheme can reproduce these complex responses. However, results depend critically on parameters regulating water transport efficiency and the cost of water stress. As these costs have not been properly identified and quantified yet, more empirical research is needed to elucidate physiological mechanisms of hydraulic failure and recover, for example embolism repair and xylem regrowth.
Collapse
Affiliation(s)
- Matteo Detto
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, New Jersey, USA
- Smithsonian Tropical Research Institute, Balboa, Panama
| | - Stephen W Pacala
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, New Jersey, USA
| |
Collapse
|
10
|
Trugman AT. Integrating plant physiology and community ecology across scales through trait-based models to predict drought mortality. THE NEW PHYTOLOGIST 2022; 234:21-27. [PMID: 34679225 DOI: 10.1111/nph.17821] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 10/02/2021] [Indexed: 06/13/2023]
Abstract
Forests are a critical carbon sink and widespread tree mortality resulting from climate-induced drought stress has the potential to alter forests from a carbon sink to a source, causing a positive feedback on climate change. Process-based vegetation models aim to represent the current understanding of the underlying mechanisms governing plant physiological and ecological responses to climate. Yet model accuracy varies across scales, and regional-scale model predictive skill is frequently poor when compared with observations of drought-driven mortality. I propose a framework that leverages differences in model predictive skill across spatial scales, mismatches between model predictions and observations, and differences in the mechanisms included and absent across models to advance the understanding of the physiological and ecological processes driving observed patterns drought-driven mortality.
Collapse
Affiliation(s)
- Anna T Trugman
- Department of Geography, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| |
Collapse
|
11
|
Verheyen K. Land-use legacies predispose the response of trees to drought in restored forests. GLOBAL CHANGE BIOLOGY 2022; 28:1204-1211. [PMID: 34791740 DOI: 10.1111/gcb.15983] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 10/11/2021] [Indexed: 06/13/2023]
Abstract
Transformative change is required to achieve conservation of the globe's natural resources. Ambitious forest restoration can help achieve this change. Restoration success depends on trees persisting through multiple stressors, with drought standing out as one of utmost importance. However, research tends to focus on tree inciting factors of tree decline, like drought, whilst ignoring the fundamental importance of context, potentially leading to the wasted restoration effort. Indeed, the propensity of trees to succumb to, or resist, drought depends on whether they are predisposed to fail or succeed. Here, I argue that this predisposition crucially depends on the nature and characteristics of the former land use at the restoration site and propose a research agenda that will help enable the successful upscaling of forest restoration ambitions by revealing the land-use history-determined conditions under which tree species are likely to succeed in an era of environmental challenges.
Collapse
Affiliation(s)
- Kris Verheyen
- Forest & Nature Lab, Department of Environment, Ghent University, Melle-Gontrode, Belgium
| |
Collapse
|
12
|
Bradford JB, Shriver RK, Robles MD, McCauley LA, Woolley TJ, Andrews CA, Crimmins M, Bell DM. Tree mortality response to drought‐density interactions suggests opportunities to enhance drought resistance. J Appl Ecol 2021. [DOI: 10.1111/1365-2664.14073] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- John. B. Bradford
- Southwest Biological Science Center U.S. Geological Survey Flagstaff AZ USA
| | - Robert K. Shriver
- Department of Natural Resources and Environmental Science University of Nevada Reno NV USA
| | - Marcos D. Robles
- Center for Science and Public Policy The Nature Conservancy Tucson AZ USA
| | - Lisa A. McCauley
- Center for Science and Public Policy The Nature Conservancy Tucson AZ USA
| | - Travis J. Woolley
- Center for Science and Public Policy The Nature Conservancy Tucson AZ USA
| | - Caitlin A. Andrews
- Southwest Biological Science Center U.S. Geological Survey Flagstaff AZ USA
| | - Michael Crimmins
- Department of Environmental Science University of Arizona Tucson AZ USA
| | - David M. Bell
- Pacific Northwest Research Station USDA Forest Service Corvallis OR USA
| |
Collapse
|
13
|
Thrippleton T, Hülsmann L, Cailleret M, Bugmann H. An evaluation of multi-species empirical tree mortality algorithms for dynamic vegetation modelling. Sci Rep 2021; 11:19845. [PMID: 34615895 PMCID: PMC8494886 DOI: 10.1038/s41598-021-98880-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 09/08/2021] [Indexed: 12/04/2022] Open
Abstract
Tree mortality is key for projecting forest dynamics, but difficult to portray in dynamic vegetation models (DVMs). Empirical mortality algorithms (MAs) are often considered promising, but little is known about DVM robustness when employing MAs of various structures and origins for multiple species. We analysed empirical MAs for a suite of European tree species within a consistent DVM framework under present and future climates in two climatically different study areas in Switzerland and evaluated their performance using empirical data from old-growth forests across Europe. DVM projections under present climate showed substantial variations when using alternative empirical MAs for the same species. Under climate change, DVM projections showed partly contrasting mortality responses for the same species. These opposing patterns were associated with MA structures (i.e. explanatory variables) and occurred independent of species ecological characteristics. When comparing simulated forest structure with data from old-growth forests, we found frequent overestimations of basal area, which can lead to flawed projections of carbon sequestration and other ecosystem services. While using empirical MAs in DVMs may appear promising, our results emphasize the importance of selecting them cautiously. We therefore synthesize our insights into a guideline for the appropriate use of empirical MAs in DVM applications.
Collapse
Affiliation(s)
- Timothy Thrippleton
- Department of Environmental Systems Science, Forest Ecology, Swiss Federal Institute of Technology (ETH Zurich), Universitätstrasse 16, 8092, Zürich, Switzerland.
- Forest Resources and Management, Sustainable Forestry, Swiss Federal Research Institute (WSL), Zürcherstrasse 111, 8903, Birmensdorf, Switzerland.
| | - Lisa Hülsmann
- Theoretical Ecology Lab, Faculty of Biology and Pre-Clinical Medicine, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - Maxime Cailleret
- INRAE, Aix-Marseille University, UMR RECOVER, 3275 Route de Cézanne, CS 40061, Aix-en-Provence Cedex 5, France
| | - Harald Bugmann
- Department of Environmental Systems Science, Forest Ecology, Swiss Federal Institute of Technology (ETH Zurich), Universitätstrasse 16, 8092, Zürich, Switzerland
| |
Collapse
|