1
|
Middleby KB, Cheesman AW, Cernusak LA. Impacts of elevated temperature and vapour pressure deficit on leaf gas exchange and plant growth across six tropical rainforest tree species. THE NEW PHYTOLOGIST 2024. [PMID: 38757766 DOI: 10.1111/nph.19822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2023] [Accepted: 04/30/2024] [Indexed: 05/18/2024]
Abstract
Elevated air temperature (Tair) and vapour pressure deficit (VPDair) significantly influence plant functioning, yet their relative impacts are difficult to disentangle. We examined the effects of elevated Tair (+6°C) and VPDair (+0.7 kPa) on the growth and physiology of six tropical tree species. Saplings were grown under well-watered conditions in climate-controlled glasshouses for 6 months under three treatments: (1) low Tair and low VPDair, (2) high Tair and low VPDair, and (3) high Tair and high VPDair. To assess acclimation, physiological parameters were measured at a set temperature. Warm-grown plants grown under elevated VPDair had significantly reduced stomatal conductance and increased instantaneous water use efficiency compared to plants grown under low VPDair. Photosynthetic biochemistry and thermal tolerance (Tcrit) were unaffected by VPDair, but elevated Tair caused Jmax25 to decrease and Tcrit to increase. Sapling biomass accumulation for all species responded positively to an increase in Tair, but elevated VPDair limited growth. This study shows that stomatal limitation caused by even moderate increases in VPDair can decrease productivity and growth rates in tropical species independently from Tair and has important implications for modelling the impacts of climate change on tropical forests.
Collapse
Affiliation(s)
- Kali B Middleby
- College of Science and Engineering, James Cook University, Cairns, QLD, 4878, Australia
| | - Alexander W Cheesman
- College of Science and Engineering, James Cook University, Cairns, QLD, 4878, Australia
| | - Lucas A Cernusak
- College of Science and Engineering, James Cook University, Cairns, QLD, 4878, Australia
| |
Collapse
|
2
|
Slot M, Rifai SW, Eze CE, Winter K. The stomatal response to vapor pressure deficit drives the apparent temperature response of photosynthesis in tropical forests. THE NEW PHYTOLOGIST 2024. [PMID: 38736030 DOI: 10.1111/nph.19806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 04/18/2024] [Indexed: 05/14/2024]
Abstract
As temperature rises, net carbon uptake in tropical forests decreases, but the underlying mechanisms are not well understood. High temperatures can limit photosynthesis directly, for example by reducing biochemical capacity, or indirectly through rising vapor pressure deficit (VPD) causing stomatal closure. To explore the independent effects of temperature and VPD on photosynthesis we analyzed photosynthesis data from the upper canopies of two tropical forests in Panama with Generalized Additive Models. Stomatal conductance and photosynthesis consistently decreased with increasing VPD, and statistically accounting for VPD increased the optimum temperature of photosynthesis (Topt) of trees from a VPD-confounded apparent Topt of c. 30-31°C to a VPD-independent Topt of c. 33-36°C, while for lianas no VPD-independent Topt was reached within the measured temperature range. Trees and lianas exhibited similar temperature and VPD responses in both forests, despite 1500 mm difference in mean annual rainfall. Over ecologically relevant temperature ranges, photosynthesis in tropical forests is largely limited by indirect effects of warming, through changes in VPD, not by direct warming effects of photosynthetic biochemistry. Failing to account for VPD when determining Topt misattributes the underlying causal mechanism and thereby hinders the advancement of mechanistic understanding of global warming effects on tropical forest carbon dynamics.
Collapse
Affiliation(s)
- Martijn Slot
- Smithsonian Tropical Research Institute, Apartado 0843-03092, Balboa, Ancón, Panama
| | - Sami W Rifai
- School of Biological Sciences, The University of Adelaide, Adelaide, SA, 5005, Australia
| | - Chinedu E Eze
- Smithsonian Tropical Research Institute, Apartado 0843-03092, Balboa, Ancón, Panama
- Department of Agronomy, Michael Okpara University of Agriculture, Umudike, Abia State, 440109, Nigeria
| | - Klaus Winter
- Smithsonian Tropical Research Institute, Apartado 0843-03092, Balboa, Ancón, Panama
| |
Collapse
|
3
|
Ač A, Jansen MAK, Grace J, Urban O. Unravelling the neglected role of ultraviolet radiation on stomata: A meta-analysis with implications for modelling ecosystem-climate interactions. PLANT, CELL & ENVIRONMENT 2024; 47:1769-1781. [PMID: 38314642 DOI: 10.1111/pce.14841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 01/17/2024] [Accepted: 01/23/2024] [Indexed: 02/06/2024]
Abstract
Stomata play a pivotal role in regulating gas exchange between plants and the atmosphere controlling water and carbon cycles. Accordingly, we investigated the impact of ultraviolet-B radiation, a neglected environmental factor varying with ongoing global change, on stomatal morphology and function by a Comprehensive Meta-Analysis. The overall UV effect at the leaf level is to decrease stomatal conductance, stomatal aperture and stomatal size, although stomatal density was increased. The significant decline in stomatal conductance is marked (6% in trees and >10% in grasses and herbs) in short-term experiments, with more modest decreases noted in long-term UV studies. Short-term experiments in growth chambers are not representative of long-term field UV effects on stomatal conductance. Important consequences of altered stomatal function are hypothesized. In the short term, UV-mediated stomatal closure may reduce carbon uptake but also water loss through transpiration, thereby alleviating deleterious effects of drought. However, in the long term, complex changes in stomatal aperture, size, and density may reduce the carbon sequestration capacity of plants and increase vegetation and land surface temperatures, potentially exacerbating negative effects of drought and/or heatwaves. Therefore, the expected future strength of carbon sink capacity in high-UV regions is likely overestimated.
Collapse
Affiliation(s)
- Alexander Ač
- Global Change Research of the Czech Academy of Sciences, Brno, Czech Republic
| | - Marcel A K Jansen
- Global Change Research of the Czech Academy of Sciences, Brno, Czech Republic
- School of Biological, Earth and Environmental Sciences, Environmental Research Institute, UCC, Cork, Ireland
| | - John Grace
- Global Change Research of the Czech Academy of Sciences, Brno, Czech Republic
- School of GeoSciences, University of Edinburgh, Edinburgh, UK
| | - Otmar Urban
- Global Change Research of the Czech Academy of Sciences, Brno, Czech Republic
| |
Collapse
|
4
|
McElwain JC, Matthaeus WJ, Barbosa C, Chondrogiannis C, O' Dea K, Jackson B, Knetge AB, Kwasniewska K, Nair R, White JD, Wilson JP, Montañez IP, Buckley YM, Belcher CM, Nogué S. Functional traits of fossil plants. THE NEW PHYTOLOGIST 2024; 242:392-423. [PMID: 38409806 DOI: 10.1111/nph.19622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Accepted: 12/19/2023] [Indexed: 02/28/2024]
Abstract
A minuscule fraction of the Earth's paleobiological diversity is preserved in the geological record as fossils. What plant remnants have withstood taphonomic filtering, fragmentation, and alteration in their journey to become part of the fossil record provide unique information on how plants functioned in paleo-ecosystems through their traits. Plant traits are measurable morphological, anatomical, physiological, biochemical, or phenological characteristics that potentially affect their environment and fitness. Here, we review the rich literature of paleobotany, through the lens of contemporary trait-based ecology, to evaluate which well-established extant plant traits hold the greatest promise for application to fossils. In particular, we focus on fossil plant functional traits, those measurable properties of leaf, stem, reproductive, or whole plant fossils that offer insights into the functioning of the plant when alive. The limitations of a trait-based approach in paleobotany are considerable. However, in our critical assessment of over 30 extant traits we present an initial, semi-quantitative ranking of 26 paleo-functional traits based on taphonomic and methodological criteria on the potential of those traits to impact Earth system processes, and for that impact to be quantifiable. We demonstrate how valuable inferences on paleo-ecosystem processes (pollination biology, herbivory), past nutrient cycles, paleobiogeography, paleo-demography (life history), and Earth system history can be derived through the application of paleo-functional traits to fossil plants.
Collapse
Affiliation(s)
- Jennifer C McElwain
- School of Natural Sciences, Botany, Trinity College Dublin, Dublin, D02 PN40, Ireland
| | - William J Matthaeus
- School of Natural Sciences, Botany, Trinity College Dublin, Dublin, D02 PN40, Ireland
| | - Catarina Barbosa
- School of Natural Sciences, Botany, Trinity College Dublin, Dublin, D02 PN40, Ireland
| | | | - Katie O' Dea
- School of Natural Sciences, Botany, Trinity College Dublin, Dublin, D02 PN40, Ireland
| | - Bea Jackson
- School of Natural Sciences, Botany, Trinity College Dublin, Dublin, D02 PN40, Ireland
| | - Antonietta B Knetge
- School of Natural Sciences, Botany, Trinity College Dublin, Dublin, D02 PN40, Ireland
| | - Kamila Kwasniewska
- School of Natural Sciences, Botany, Trinity College Dublin, Dublin, D02 PN40, Ireland
| | - Richard Nair
- School of Natural Sciences, Botany, Trinity College Dublin, Dublin, D02 PN40, Ireland
| | - Joseph D White
- Department of Biology, Baylor University, Waco, 76798-7388, TX, USA
| | - Jonathan P Wilson
- Department of Environmental Studies, Haverford College, Haverford, Pennsylvania, 19041, PA, USA
| | - Isabel P Montañez
- UC Davis Institute of the Environment, University of California, Davis, CA, 95616, USA
- Department of Earth and Planetary Sciences, University of California, Davis, CA, 95616, USA
| | - Yvonne M Buckley
- School of Natural Sciences, Zoology, Trinity College Dublin, Dublin, D02 PN40, Ireland
| | | | - Sandra Nogué
- Universitat Autònoma de Barcelona, Bellaterra (Cerdanyola del Vallès), 08193, Catalonia, Spain
- CREAF, Bellaterra (Cerdanyola del Vallès), 08193, Catalonia, Spain
| |
Collapse
|
5
|
Lamour J, Souza DC, Gimenez BO, Higuchi N, Chave J, Chambers J, Rogers A. Wood-density has no effect on stomatal control of leaf-level water use efficiency in an Amazonian forest. PLANT, CELL & ENVIRONMENT 2023; 46:3806-3821. [PMID: 37635450 DOI: 10.1111/pce.14704] [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: 03/24/2023] [Revised: 07/20/2023] [Accepted: 08/16/2023] [Indexed: 08/29/2023]
Abstract
Forest disturbances increase the proportion of fast-growing tree species compared to slow-growing ones. To understand their relative capacity for carbon uptake and their vulnerability to climate change, and to represent those differences in Earth system models, it is necessary to characterise the physiological differences in their leaf-level control of water use efficiency and carbon assimilation. We used wood density as a proxy for the fast-slow growth spectrum and tested the assumption that trees with a low wood density (LWD) have a lower water-use efficiency than trees with a high wood density (HWD). We selected 5 LWD tree species and 5 HWD tree species growing in the same location in an Amazonian tropical forest and measured in situ steady-state gas exchange on top-of-canopy leaves with parallel sampling and measurement of leaf mass area and leaf nitrogen content. We found that LWD species invested more nitrogen in photosynthetic capacity than HWD species, had higher photosynthetic rates and higher stomatal conductance. However, contrary to expectations, we showed that the stomatal control of the balance between transpiration and carbon assimilation was similar in LWD and HWD species and that they had the same dark respiration rates.
Collapse
Affiliation(s)
- Julien Lamour
- Department of Environmental & Climate Sciences, Brookhaven National Laboratory, Upton, New York, USA
- Evolution and Biological Diversity (EDB), CNRS/IRD/UPS, Toulouse, France
| | - Daisy C Souza
- National Institute of Amazonian Research (INPA), Forest Management Laboratory (LMF), Manaus, Amazonas, Brazil
| | - Bruno O Gimenez
- National Institute of Amazonian Research (INPA), Forest Management Laboratory (LMF), Manaus, Amazonas, Brazil
- Department of Geography, University of California, Berkeley, California, USA
| | - Niro Higuchi
- National Institute of Amazonian Research (INPA), Forest Management Laboratory (LMF), Manaus, Amazonas, Brazil
| | - Jérôme Chave
- Evolution and Biological Diversity (EDB), CNRS/IRD/UPS, Toulouse, France
| | - Jeffrey Chambers
- Department of Geography, University of California, Berkeley, California, USA
| | - Alistair Rogers
- Department of Environmental & Climate Sciences, Brookhaven National Laboratory, Upton, New York, USA
| |
Collapse
|
6
|
Brissette LEG, Wong CYS, McHugh DP, Au J, Orcutt EL, Klein MC, Magney TS. Tracking canopy chlorophyll fluorescence with a low-cost light emitting diode platform. AOB PLANTS 2023; 15:plad069. [PMID: 37937046 PMCID: PMC10626922 DOI: 10.1093/aobpla/plad069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 10/12/2023] [Indexed: 11/09/2023]
Abstract
Chlorophyll fluorescence measured at the leaf scale through pulse amplitude modulation (PAM) has provided valuable insight into photosynthesis. At the canopy- and satellite-scale, solar-induced fluorescence (SIF) provides a method to estimate the photosynthetic activity of plants across spatiotemporal scales. However, retrieving SIF signal remotely requires instruments with high spectral resolution, making it difficult and often expensive to measure canopy-level steady-state chlorophyll fluorescence under natural sunlight. Considering this, we built a novel low-cost photodiode system that retrieves far-red chlorophyll fluorescence emission induced by a blue light emitting diode (LED) light source, for 2 h at night, above the canopy. Our objective was to determine if an active remote sensing-based night-time photodiode method could track changes in canopy-scale LED-induced chlorophyll fluorescence (LEDIF) during an imposed drought on a broadleaf evergreen shrub, Polygala myrtifolia. Far-red LEDIF (720-740 nm) was retrieved using low-cost photodiodes (LEDIFphotodiode) and validated against measurements from a hyperspectral spectroradiometer (LEDIFhyperspectral). To link the LEDIF signal with physiological drought response, we tracked stomatal conductance (gsw) using a porometer, two leaf-level vegetation indices-photochemical reflectance index and normalized difference vegetation index-to represent xanthophyll and chlorophyll pigment dynamics, respectively, and a PAM fluorimeter to measure photochemical and non-photochemical dynamics. Our results demonstrate a similar performance between the photodiode and hyperspectral retrievals of LEDIF (R2 = 0.77). Furthermore, LEDIFphotodiode closely tracked drought responses associated with a decrease in photochemical quenching (R2 = 0.69), Fv/Fm (R2 = 0.59) and leaf-level photochemical reflectance index (R2 = 0.59). Therefore, the low-cost LEDIFphotodiode approach has the potential to be a meaningful indicator of photosynthetic activity at spatial scales greater than an individual leaf and over time.
Collapse
Affiliation(s)
- Logan E G Brissette
- Department of Plant Sciences, University of California, Davis, Davis, CA 95616, USA
| | - Christopher Y S Wong
- Department of Plant Sciences, University of California, Davis, Davis, CA 95616, USA
| | - Devin P McHugh
- Department of Plant Sciences, University of California, Davis, Davis, CA 95616, USA
| | - Jessie Au
- Department of Plant Sciences, University of California, Davis, Davis, CA 95616, USA
| | - Erica L Orcutt
- Department of Plant Sciences, University of California, Davis, Davis, CA 95616, USA
- Department of Geography, California State University, Sacramento, Sacramento, CA 95819, USA
| | - Marie C Klein
- Department of Plant Sciences, University of California, Davis, Davis, CA 95616, USA
| | - Troy S Magney
- Department of Plant Sciences, University of California, Davis, Davis, CA 95616, USA
| |
Collapse
|
7
|
Tomasella M, Calderan A, Mihelčič A, Petruzzellis F, Braidotti R, Natale S, Lisjak K, Sivilotti P, Nardini A. Best Procedures for Leaf and Stem Water Potential Measurements in Grapevine: Cultivar and Water Status Matter. PLANTS (BASEL, SWITZERLAND) 2023; 12:2412. [PMID: 37446973 DOI: 10.3390/plants12132412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 06/19/2023] [Accepted: 06/20/2023] [Indexed: 07/15/2023]
Abstract
The pressure chamber is the most used tool for plant water status monitoring. However, species/cultivar and seasonal effects on protocols for reliable water potential determination have not been properly tested. In four grapevine cultivars and two times of the season (early season, Es; late season, Ls, under moderate drought), we assessed the maximum sample storage time before leaf water potential (Ψleaf) measurements and the minimum equilibration time for stem water potential (Ψstem) determination, taking 24 h leaf cover as control. In 'Pinot gris', Ψleaf already decreased after 1 h leaf storage in both campaigns, dropping by 0.4/0.5 MPa after 3 h, while in 'Refosk', it decreased by 0.1 MPa after 1 and 2 h in Es and Ls, respectively. In 'Merlot' and 'Merlot Kanthus', even 3 h storage did not affect Ψleaf. In Es, the minimum Ψstem equilibration was 1 h for 'Refošk' and 10 min for 'Pinot gris' and 'Merlot'. In Ls, 'Merlot Kanthus' required more than 2 h equilibration, while 1 h to 10 min was sufficient for the other cultivars. The observed cultivar and seasonal differences indicate that the proposed tests should be routinely performed prior to experiments to define ad hoc procedures for water status determination.
Collapse
Affiliation(s)
- Martina Tomasella
- Department of Life Sciences, University of Trieste, via L. Giorgieri 10, 34127 Trieste, Italy
| | - Alberto Calderan
- Department of Life Sciences, University of Trieste, via L. Giorgieri 10, 34127 Trieste, Italy
- Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Via delle Scienze 206, 33100 Udine, Italy
| | - Alenka Mihelčič
- Department of Fruit Growing, Agricultural Institute of Slovenia, Viticulture and Enology, Hacquetova Ulica 17, SI-1000 Ljubljana, Slovenia
| | - Francesco Petruzzellis
- Department of Life Sciences, University of Trieste, via L. Giorgieri 10, 34127 Trieste, Italy
| | - Riccardo Braidotti
- Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Via delle Scienze 206, 33100 Udine, Italy
| | - Sara Natale
- Department of Life Sciences, University of Trieste, via L. Giorgieri 10, 34127 Trieste, Italy
- Department of Biology, University of Padova, Via Ugo Bassi 58B, 35121 Padova, Italy
| | - Klemen Lisjak
- Department of Fruit Growing, Agricultural Institute of Slovenia, Viticulture and Enology, Hacquetova Ulica 17, SI-1000 Ljubljana, Slovenia
| | - Paolo Sivilotti
- Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Via delle Scienze 206, 33100 Udine, Italy
| | - Andrea Nardini
- Department of Life Sciences, University of Trieste, via L. Giorgieri 10, 34127 Trieste, Italy
| |
Collapse
|
8
|
Liao Q, Ding R, Du T, Kang S, Tong L, Li S. Salinity-specific stomatal conductance model parameters are reduced by stomatal saturation conductance and area via leaf nitrogen. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 876:162584. [PMID: 36889407 DOI: 10.1016/j.scitotenv.2023.162584] [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: 12/14/2022] [Revised: 02/08/2023] [Accepted: 02/27/2023] [Indexed: 06/18/2023]
Abstract
Modeling stomatal behavior is necessary for accurate stomatal simulation and predicting the terrestrial water‑carbon cycle. Although the Ball-Berry and Medlyn stomatal conductance (gs) models have been widely used, variations and the drivers of their key slope parameters (m and g1) remain poorly understood under salinity stress. We measured leaf gas exchange, physiological and biochemical traits, soil water content and electrical conductivity of saturation extract (ECe), and fitted slope parameters of two genotypes of maize growing in two water and two salinity levels. We found m was different between the genotypes, but no difference in g1. Salinity stress reduced m and g1, saturated stomatal conductance (gsat), the fraction of leaf epidermis area allocation to stomata (fs), and leaf nitrogen (N) content, and increased ECe, but no marked decrease in slope parameters under drought. Both m and g1 were positively correlated with gsat, fs, and leaf N content, and negatively correlated with ECe in the same fashion among the two genotypes. Salinity stress altered m and g1 by modulating gsat and fs via leaf N content. The prediction accuracy of gs was improved using salinity-specific slope parameters, with root mean square error (RMSE) being decreased from 0.056 to 0.046 and 0.066 to 0.025 mol m-2 s-1 for the Ball-Berry and Medlyn models, respectively. This study provides a modeling approach to improving the simulation of stomatal conductance under salinity.
Collapse
Affiliation(s)
- Qi Liao
- Center for Agricultural Water Research in China, China Agricultural University, Beijing 100083, China; National Field Scientific Observation and Research Station on Efficient Water Use of Oasis Agriculture, Wuwei, Gansu Province 733009, China
| | - Risheng Ding
- Center for Agricultural Water Research in China, China Agricultural University, Beijing 100083, China; National Field Scientific Observation and Research Station on Efficient Water Use of Oasis Agriculture, Wuwei, Gansu Province 733009, China.
| | - Taisheng Du
- Center for Agricultural Water Research in China, China Agricultural University, Beijing 100083, China; National Field Scientific Observation and Research Station on Efficient Water Use of Oasis Agriculture, Wuwei, Gansu Province 733009, China
| | - Shaozhong Kang
- Center for Agricultural Water Research in China, China Agricultural University, Beijing 100083, China; National Field Scientific Observation and Research Station on Efficient Water Use of Oasis Agriculture, Wuwei, Gansu Province 733009, China
| | - Ling Tong
- Center for Agricultural Water Research in China, China Agricultural University, Beijing 100083, China; National Field Scientific Observation and Research Station on Efficient Water Use of Oasis Agriculture, Wuwei, Gansu Province 733009, China
| | - Shuai Li
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| |
Collapse
|
9
|
Lamour J, Davidson KJ, Ely KS, Le Moguédec G, Anderson JA, Li Q, Calderón O, Koven CD, Wright SJ, Walker AP, Serbin SP, Rogers A. The effect of the vertical gradients of photosynthetic parameters on the CO 2 assimilation and transpiration of a Panamanian tropical forest. THE NEW PHYTOLOGIST 2023; 238:2345-2362. [PMID: 36960539 DOI: 10.1111/nph.18901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 03/14/2023] [Indexed: 05/19/2023]
Abstract
Terrestrial biosphere models (TBMs) include the representation of vertical gradients in leaf traits associated with modeling photosynthesis, respiration, and stomatal conductance. However, model assumptions associated with these gradients have not been tested in complex tropical forest canopies. We compared TBM representation of the vertical gradients of key leaf traits with measurements made in a tropical forest in Panama and then quantified the impact of the observed gradients on simulated canopy-scale CO2 and water fluxes. Comparison between observed and TBM trait gradients showed divergence that impacted canopy-scale simulations of water vapor and CO2 exchange. Notably, the ratio between the dark respiration rate and the maximum carboxylation rate was lower near the ground than at the top-of-canopy, leaf-level water-use efficiency was markedly higher at the top-of-canopy, and the decrease in maximum carboxylation rate from the top-of-canopy to the ground was less than TBM assumptions. The representation of the gradients of leaf traits in TBMs is typically derived from measurements made within-individual plants, or, for some traits, assumed constant due to a lack of experimental data. Our work shows that these assumptions are not representative of the trait gradients observed in species-rich, complex tropical forests.
Collapse
Affiliation(s)
- Julien Lamour
- Environmental & Climate Sciences Department, Brookhaven National Laboratory, Upton, NY, 11973, USA
| | - Kenneth J Davidson
- Environmental & Climate Sciences Department, Brookhaven National Laboratory, Upton, NY, 11973, USA
- Department of Ecology and Evolution, Stony Brook University, Stony Brook, NY, 11974, USA
| | - Kim S Ely
- Environmental & Climate Sciences Department, Brookhaven National Laboratory, Upton, NY, 11973, USA
| | - Gilles Le Moguédec
- AMAP, Université Montpellier, INRAE, Cirad CNRS, IRD, Montpellier, 34000, France
| | - Jeremiah A Anderson
- Environmental & Climate Sciences Department, Brookhaven National Laboratory, Upton, NY, 11973, USA
| | - Qianyu Li
- Environmental & Climate Sciences Department, Brookhaven National Laboratory, Upton, NY, 11973, USA
| | - Osvaldo Calderón
- Smithsonian Tropical Research Institute, Balboa, 0843-03092, Republic of Panama
| | - Charles D Koven
- Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - S Joseph Wright
- Smithsonian Tropical Research Institute, Balboa, 0843-03092, Republic of Panama
| | - Anthony P Walker
- Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Shawn P Serbin
- Environmental & Climate Sciences Department, Brookhaven National Laboratory, Upton, NY, 11973, USA
| | - Alistair Rogers
- Environmental & Climate Sciences Department, Brookhaven National Laboratory, Upton, NY, 11973, USA
| |
Collapse
|
10
|
Mujawamariya M, Wittemann M, Dusenge ME, Manishimwe A, Ntirugulirwa B, Zibera E, Nsabimana D, Wallin G, Uddling J. Contrasting warming responses of photosynthesis in early- and late-successional tropical trees. TREE PHYSIOLOGY 2023:tpad035. [PMID: 36971469 DOI: 10.1093/treephys/tpad035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 02/01/2023] [Indexed: 06/18/2023]
Abstract
The productivity and climate feedbacks of tropical forests depend on tree physiological responses to warmer and, over large areas, seasonally drier conditions. However, knowledge regarding such responses is limited due to data scarcity. We studied the impact of growth temperature on net photosynthesis (An), maximum rates of Rubisco carboxylation at 25°C (Vcmax25), stomatal conductance (gs) and the slope parameter of the stomatal conductance-photosynthesis model (g1), in ten early- (ES) and eight late-successional (LS) tropical tree species grown at three sites along an elevation gradient in Rwanda, differing by 6.8°C in daytime ambient air temperature. The effect of seasonal drought on An was also investigated. We found that warm climate decreased wet-season An in LS species, but not in ES species. Values of Vcmax25 were lower at the warmest site across both successional groups, and An and Vcmax25 were higher in ES compared to LS species. Stomatal conductance exhibited no significant site differences and g1 was similar across both sites and successional groups. Drought strongly reduced An at warmer sites but not at the coolest montane site and this response was similar in both ES and LS species. Our results suggest that warming has negative effects on leaf-level photosynthesis in LS species, while both LS and ES species suffer photosynthesis declines in a warmer climate with more pronounced droughts. The contrasting responses of An between successional groups may lead to shifts in species' competitive balance in a warmer world, to the disadvantage of LS trees.
Collapse
Affiliation(s)
- Myriam Mujawamariya
- Department of Biology, College of Science and Technology, University of Rwanda, Avenue de l'Armée, Kigali P.O.Box 3900, Rwanda
- Center of Excellence in Biodiversity Conservation and Natural Resources Management, College of Science and Technology, University of Rwanda, Avenue de l'Armée, Kigali P.O.Box 3900, Rwanda
- Department of Biological and Environmental Sciences, University of Gothenburg, P.O. Box 461, SE-405 30 Gothenburg, Sweden
| | - Maria Wittemann
- Department of Biological and Environmental Sciences, University of Gothenburg, P.O. Box 461, SE-405 30 Gothenburg, Sweden
| | - Mirindi Eric Dusenge
- Western Center for Climate Change, Sustainable Livelihoods and Health, Department of Geography, The University of Western Ontario, London, Ontario, Canada
- College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4RJ, United Kingdom
| | - Aloysie Manishimwe
- Department of Biology, College of Science and Technology, University of Rwanda, Avenue de l'Armée, Kigali P.O.Box 3900, Rwanda
- Center of Excellence in Biodiversity Conservation and Natural Resources Management, College of Science and Technology, University of Rwanda, Avenue de l'Armée, Kigali P.O.Box 3900, Rwanda
- Department of Biological and Environmental Sciences, University of Gothenburg, P.O. Box 461, SE-405 30 Gothenburg, Sweden
| | - Bonaventure Ntirugulirwa
- Department of Biology, College of Science and Technology, University of Rwanda, Avenue de l'Armée, Kigali P.O.Box 3900, Rwanda
- Department of Biological and Environmental Sciences, University of Gothenburg, P.O. Box 461, SE-405 30 Gothenburg, Sweden
- Rwanda Forestry Authority, Muhanga P.O. Box 46, Rwanda
| | - Etienne Zibera
- School of Forestry and Biodiversity, College of Agriculture, Animal Sciences and Veterinary Medicine, University of Rwanda, Musanze P.O. Box 210, Rwanda
| | - Donat Nsabimana
- Center of Excellence in Biodiversity Conservation and Natural Resources Management, College of Science and Technology, University of Rwanda, Avenue de l'Armée, Kigali P.O.Box 3900, Rwanda
- School of Forestry and Biodiversity, College of Agriculture, Animal Sciences and Veterinary Medicine, University of Rwanda, Musanze P.O. Box 210, Rwanda
| | - Göran Wallin
- Department of Biological and Environmental Sciences, University of Gothenburg, P.O. Box 461, SE-405 30 Gothenburg, Sweden
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, OX1 3QY, United Kingdom
| | - Johan Uddling
- Department of Biological and Environmental Sciences, University of Gothenburg, P.O. Box 461, SE-405 30 Gothenburg, Sweden
| |
Collapse
|
11
|
Davidson KJ, Lamour J, Rogers A, Ely KS, Li Q, McDowell NG, Pivovaroff AL, Wolfe BT, Wright SJ, Zambrano A, Serbin SP. Short-term variation in leaf-level water use efficiency in a tropical forest. THE NEW PHYTOLOGIST 2023; 237:2069-2087. [PMID: 36527230 DOI: 10.1111/nph.18684] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 12/13/2022] [Indexed: 06/17/2023]
Abstract
The representation of stomatal regulation of transpiration and CO2 assimilation is key to forecasting terrestrial ecosystem responses to global change. Given its importance in determining the relationship between forest productivity and climate, accurate and mechanistic model representation of the relationship between stomatal conductance (gs ) and assimilation is crucial. We assess possible physiological and mechanistic controls on the estimation of the g1 (stomatal slope, inversely proportional to water use efficiency) and g0 (stomatal intercept) parameters, using diurnal gas exchange surveys and leaf-level response curves of six tropical broadleaf evergreen tree species. g1 estimated from ex situ response curves averaged 50% less than g1 estimated from survey data. While g0 and g1 varied between leaves of different phenological stages, the trend was not consistent among species. We identified a diurnal trend associated with g1 and g0 that significantly improved model projections of diurnal trends in transpiration. The accuracy of modeled gs can be improved by accounting for variation in stomatal behavior across diurnal periods, and between measurement approaches, rather than focusing on phenological variation in stomatal behavior. Additional investigation into the primary mechanisms responsible for diurnal variation in g1 will be required to account for this phenomenon in land-surface models.
Collapse
Affiliation(s)
- Kenneth J Davidson
- Department of Environmental and Climate Sciences, Brookhaven National Laboratory, Building 490A, Upton, NY, 11973, USA
- Department of Ecology and Evolution, Stony Brook University, 650 Life Sciences Building, Stony Brook, NY, 11794, USA
| | - Julien Lamour
- Department of Environmental and Climate Sciences, Brookhaven National Laboratory, Building 490A, Upton, NY, 11973, USA
| | - Alistair Rogers
- Department of Environmental and Climate Sciences, Brookhaven National Laboratory, Building 490A, Upton, NY, 11973, USA
| | - Kim S Ely
- Department of Environmental and Climate Sciences, Brookhaven National Laboratory, Building 490A, Upton, NY, 11973, USA
| | - Qianyu Li
- Department of Environmental and Climate Sciences, Brookhaven National Laboratory, Building 490A, Upton, NY, 11973, USA
| | - Nate G McDowell
- Atmospheric Sciences and Global Change Division, Pacific Northwest National Laboratory, PO Box 999, Richland, WA, 99352, USA
- School of Biological Sciences, Washington State University, PO Box 644236, Pullman, WA, 99164-4236, USA
| | | | - Brett T Wolfe
- School of Renewable Natural Resources, Louisiana State University, Room 227, Renewable Natural Resources Bldg, Baton Rouge, LA, 70803, USA
- Smithsonian Tropical Research Institute, Apartado, 0843-03092, Balboa, Panama
| | - S Joseph Wright
- Smithsonian Tropical Research Institute, Apartado, 0843-03092, Balboa, Panama
| | - Alfonso Zambrano
- Smithsonian Tropical Research Institute, Apartado, 0843-03092, Balboa, Panama
| | - Shawn P Serbin
- Department of Environmental and Climate Sciences, Brookhaven National Laboratory, Building 490A, Upton, NY, 11973, USA
| |
Collapse
|
12
|
Wolfe BT, Detto M, Zhang YJ, Anderson-Teixeira KJ, Brodribb T, Collins AD, Crawford C, Dickman LT, Ely KS, Francisco J, Gurry PD, Hancock H, King CT, Majekobaje AR, Mallett CJ, McDowell NG, Mendheim Z, Michaletz ST, Myers DB, Price TJ, Rogers A, Sack L, Serbin SP, Siddiq Z, Willis D, Wu J, Zailaa J, Wright SJ. Leaves as bottlenecks: The contribution of tree leaves to hydraulic resistance within the soil-plant-atmosphere continuum. PLANT, CELL & ENVIRONMENT 2023; 46:736-746. [PMID: 36564901 DOI: 10.1111/pce.14524] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 12/12/2022] [Accepted: 12/21/2022] [Indexed: 06/17/2023]
Abstract
Within vascular plants, the partitioning of hydraulic resistance along the soil-to-leaf continuum affects transpiration and its response to environmental conditions. In trees, the fractional contribution of leaf hydraulic resistance (Rleaf ) to total soil-to-leaf hydraulic resistance (Rtotal ), or fRleaf (=Rleaf /Rtotal ), is thought to be large, but this has not been tested comprehensively. We compiled a multibiome data set of fRleaf using new and previously published measurements of pressure differences within trees in situ. Across 80 samples, fRleaf averaged 0.51 (95% confidence interval [CI] = 0.46-0.57) and it declined with tree height. We also used the allometric relationship between field-based measurements of soil-to-leaf hydraulic conductance and laboratory-based measurements of leaf hydraulic conductance to compute the average fRleaf for 19 tree samples, which was 0.40 (95% CI = 0.29-0.56). The in situ technique produces a more accurate descriptor of fRleaf because it accounts for dynamic leaf hydraulic conductance. Both approaches demonstrate the outsized role of leaves in controlling tree hydrodynamics. A larger fRleaf may help stems from loss of hydraulic conductance. Thus, the decline in fRleaf with tree height would contribute to greater drought vulnerability in taller trees and potentially to their observed disproportionate drought mortality.
Collapse
Affiliation(s)
- Brett T Wolfe
- School of Renewable Natural Resources, Louisiana State University Agricultural Center, Baton Rouge, Louisiana, USA
- Smithsonian Tropical Research Institute, Balboa, Republic of Panama
| | - Matteo Detto
- Smithsonian Tropical Research Institute, Balboa, Republic of Panama
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, New Jersey, USA
| | - Yong-Jiang Zhang
- School of Biology and Ecology, University of Maine, Orono, Maine, USA
| | - Kristina J Anderson-Teixeira
- Smithsonian Tropical Research Institute, Balboa, Republic of Panama
- Conservation Ecology Center, Smithsonian's National Zoo & Conservation Biology Institute, Front Royal, Virginia, USA
| | - Tim Brodribb
- School of Natural Sciences, University of Tasmania, Hobart, Australia
| | - Adam D Collins
- Los Alamos National Laboratory, Earth and Environmental Sciences Division, Los Alamos, New Mexico, USA
| | - Chloe Crawford
- School of Renewable Natural Resources, Louisiana State University Agricultural Center, Baton Rouge, Louisiana, USA
| | - L Turin Dickman
- Los Alamos National Laboratory, Earth and Environmental Sciences Division, Los Alamos, New Mexico, USA
| | - Kim S Ely
- Brookhaven National Laboratory, Environmental and Climate Science Department, Upton, New York, USA
| | - Jessica Francisco
- School of Renewable Natural Resources, Louisiana State University Agricultural Center, Baton Rouge, Louisiana, USA
| | - Preston D Gurry
- School of Renewable Natural Resources, Louisiana State University Agricultural Center, Baton Rouge, Louisiana, USA
| | - Haigan Hancock
- School of Renewable Natural Resources, Louisiana State University Agricultural Center, Baton Rouge, Louisiana, USA
| | - Christopher T King
- School of Renewable Natural Resources, Louisiana State University Agricultural Center, Baton Rouge, Louisiana, USA
| | - Adelodun R Majekobaje
- School of Renewable Natural Resources, Louisiana State University Agricultural Center, Baton Rouge, Louisiana, USA
| | - Christian J Mallett
- School of Renewable Natural Resources, Louisiana State University Agricultural Center, Baton Rouge, Louisiana, USA
| | - Nate G McDowell
- Pacific Northwest National Lab, Atmospheric Sciences and Global Change Division, Richland, Washington, USA
- School of Biological Sciences, Washington State University, Pullman, Washington, USA
| | - Zachary Mendheim
- School of Renewable Natural Resources, Louisiana State University Agricultural Center, Baton Rouge, Louisiana, USA
| | - Sean T Michaletz
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Daniel B Myers
- School of Renewable Natural Resources, Louisiana State University Agricultural Center, Baton Rouge, Louisiana, USA
| | - Ty J Price
- School of Renewable Natural Resources, Louisiana State University Agricultural Center, Baton Rouge, Louisiana, USA
| | - Alistair Rogers
- Brookhaven National Laboratory, Environmental and Climate Science Department, Upton, New York, USA
| | - Lawren Sack
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, California, USA
| | - Shawn P Serbin
- Brookhaven National Laboratory, Environmental and Climate Science Department, Upton, New York, USA
| | - Zafar Siddiq
- Department of Botany, Government College University, Lahore, Pakistan
| | - David Willis
- School of Renewable Natural Resources, Louisiana State University Agricultural Center, Baton Rouge, Louisiana, USA
| | - Jin Wu
- School of Biological Sciences, Research Area of Ecology and Biodiversity, The University of Hong Kong, Hong Kong, China
- State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, China
| | - Joseph Zailaa
- Conservation Ecology Center, Smithsonian's National Zoo & Conservation Biology Institute, Front Royal, Virginia, USA
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, California, USA
- School of the Environment, Yale University, New Haven, Connecticut, USA
| | - S Joseph Wright
- Smithsonian Tropical Research Institute, Balboa, Republic of Panama
| |
Collapse
|
13
|
Garen JC, Branch HA, Borrego I, Blonder B, Stinziano JR, Michaletz ST. Gas exchange analysers exhibit large measurement error driven by internal thermal gradients. THE NEW PHYTOLOGIST 2022; 236:369-384. [PMID: 35762843 DOI: 10.1111/nph.18347] [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: 04/05/2022] [Accepted: 06/17/2022] [Indexed: 06/15/2023]
Abstract
Portable gas exchange analysers provide critical data for understanding plant-atmosphere carbon and water fluxes, and for parameterising Earth system models that forecast climate change effects and feedbacks. We characterised temperature measurement errors in the Li-Cor LI-6400XT and LI-6800, and estimated downstream errors in derived quantities, including stomatal conductance (gsw ) and leaf intercellular CO2 concentration (Ci ). The LI-6400XT exhibited air temperature errors (differences between reported air temperature and air temperature measured near the leaf) up to 7.2°C, leaf temperature errors up to 5.3°C, and relative errors in gsw and Ci that increased as temperatures departed from ambient. This caused errors in leaf-to-air temperature relationships, assimilation-temperature curves and CO2 response curves. Temperature dependencies of maximum Rubisco carboxylation rate (Vcmax ) and maximum RuBP regeneration rate (Jmax ) showed errors of 12% and 35%, respectively. These errors are likely to be idiosyncratic and may differ among machines and environmental conditions. The LI-6800 exhibited much smaller errors. Earth system model predictions may be erroneous, as much of their parametrisation data were measured on the LI-6400XT system, depending on the methods used. We make recommendations for minimising errors and correcting data in the LI-6400XT. We also recommend transitioning to the LI-6800 for future data collection.
Collapse
Affiliation(s)
- Josef C Garen
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Haley A Branch
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Isaac Borrego
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Benjamin Blonder
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA, 94720, USA
| | | | - Sean T Michaletz
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| |
Collapse
|
14
|
Ding R, Xie J, Mayfield‐Jones D, Zhang Y, Kang S, Leakey ADB. Plasticity in stomatal behaviour across a gradient of water supply is consistent among field-grown maize inbred lines with varying stomatal patterning. PLANT, CELL & ENVIRONMENT 2022; 45:2324-2336. [PMID: 35590441 PMCID: PMC9541397 DOI: 10.1111/pce.14358] [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: 10/28/2021] [Revised: 04/30/2022] [Accepted: 05/08/2022] [Indexed: 05/14/2023]
Abstract
Stomata regulate leaf CO2 assimilation (A) and water loss. The Ball-Berry and Medlyn models predict stomatal conductance (gs ) with a slope parameter (m or g1 ) that reflects the sensitivity of gs to A, atmospheric CO2 and humidity, and is inversely related to water use efficiency (WUE). This study addressed knowledge gaps about what the values of m and g1 are in C4 crops under field conditions, as well as how they vary among genotypes and with drought stress. Four inbred maize genotypes were unexpectedly consistent in how m and g1 decreased as water supply decreased. This was despite genotypic variation in stomatal patterning, A and gs . m and g1 were strongly correlated with soil water content, moderately correlated with predawn leaf water potential (Ψpd ), but not correlated with midday leaf water potential (Ψmd ). This implied that m and g1 respond to long-term water supply more than short-term drought stress. The conserved nature of m and g1 across anatomically diverse genotypes and water supplies suggests there is flexibility in structure-function relationships underpinning WUE. This evidence can guide the simulation of maize gs across a range of water supply in the primary maize growing region and inform efforts to improve WUE.
Collapse
Affiliation(s)
- Risheng Ding
- Center for Agricultural Water Research in ChinaChina Agricultural UniversityBeijingChina
- National Field Scientific Observation and Research Station on Efficient Water Use of Oasis AgricultureChina Agricultural UniversityWuweiGansuChina
| | - Jiayang Xie
- Department of Crop SciencesUniversity of Illinois at Urbana‐ChampaignUrbanaIllinoisUSA
- Institute for Genomic BiologyUniversity of Illinois at Urbana‐ChampaignUrbanaIllinoisUSA
| | - Dustin Mayfield‐Jones
- Institute for Genomic BiologyUniversity of Illinois at Urbana‐ChampaignUrbanaIllinoisUSA
- Department of Plant BiologyUniversity of Illinois at Urbana‐ChampaignUrbanaIllinoisUSA
| | - Yanqun Zhang
- State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, Department of Irrigation and DrainageChina Institute of Water Resources and Hydropower ResearchBeijingChina
| | - Shaozhong Kang
- Center for Agricultural Water Research in ChinaChina Agricultural UniversityBeijingChina
- National Field Scientific Observation and Research Station on Efficient Water Use of Oasis AgricultureChina Agricultural UniversityWuweiGansuChina
| | - Andrew D. B. Leakey
- Department of Crop SciencesUniversity of Illinois at Urbana‐ChampaignUrbanaIllinoisUSA
- Institute for Genomic BiologyUniversity of Illinois at Urbana‐ChampaignUrbanaIllinoisUSA
- Department of Plant BiologyUniversity of Illinois at Urbana‐ChampaignUrbanaIllinoisUSA
| |
Collapse
|
15
|
Davidson KJ, Lamour J, Rogers A, Serbin SP. Late-day measurement of excised branches results in uncertainty in the estimation of two stomatal parameters derived from response curves in Populus deltoides Bartr. × Populus nigra L. TREE PHYSIOLOGY 2022; 42:1377-1395. [PMID: 35134232 DOI: 10.1093/treephys/tpac006] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 01/17/2022] [Indexed: 06/14/2023]
Abstract
Many terrestrial biosphere models depend on an understanding of the relationship between stomatal conductance and photosynthesis. However, unlike the measurement of photosynthetic parameters, such as the maximum carboxylation capacity, where standard methods (e.g., CO2 response or ACi curves) are widely accepted, a consensus method for empirically measuring parameters representing stomatal response has not yet emerged. Most models of stomatal response to environment represent stomatal conductance as being bounded by a lower intercept parameter (g0), and linearly scaled based on a multivariate term described by the stomatal slope parameter (g1). Here we employ the widely used Unified Stomatal Optimization model, to test whether g1 and g0 parameters are impacted by the choice of measurement method, either on an intact branch or a cut branch segment stored in water. We measured paired stomatal response curves on intact and excised branches of a hybrid poplar clone (Populus deltoides Bartr. × Populus nigra L. OP367), measured twice over a diurnal period. We found that predawn branch excision did not significantly affect measured g0 and g1 when measured within 4 h of excision. Measurement in the afternoon resulted in significantly higher values of g1 and lower values of g0, with values changing by 55% and 56%, respectively. Excision combined with afternoon measurement resulted in a marked effect on parameter estimates, with g1 increasing 89% from morning to afternoon and a 25% lower g1 for cut branches than those measured in situ. We also show that in hybrid poplar the differences in parameter estimates obtained from plants measured under different conditions can directly impact models of canopy function, reducing modeled transpiration by 18% over a simulated 12.5-h period. Although these results are only for a single isohydric woody species, our findings suggest that stomatal optimality parameters may not remain constant throughout the day.
Collapse
Affiliation(s)
- Kenneth J Davidson
- Department of Environmental and Climate Sciences, Brookhaven National Laboratory, Upton, NY 11973, USA
- Department of Ecology and Evolution, Stony Brook University, 650 Life Sciences Building, Stony Brook, NY 11794, USA
| | - Julien Lamour
- Department of Environmental and Climate Sciences, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Alistair Rogers
- Department of Environmental and Climate Sciences, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Shawn P Serbin
- Department of Environmental and Climate Sciences, Brookhaven National Laboratory, Upton, NY 11973, USA
| |
Collapse
|
16
|
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
|
17
|
Li Y, Zhang Y, Lv J. Interannual variations in GPP in forest ecosystems in Southwest China and regional differences in the climatic contributions. ECOL INFORM 2022. [DOI: 10.1016/j.ecoinf.2022.101591] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
18
|
Rodriguez‐Dominguez CM, Forner A, Martorell S, Choat B, Lopez R, Peters JMR, Pfautsch S, Mayr S, Carins‐Murphy MR, McAdam SAM, Richardson F, Diaz‐Espejo A, Hernandez‐Santana V, Menezes‐Silva PE, Torres‐Ruiz JM, Batz TA, Sack L. Leaf water potential measurements using the pressure chamber: Synthetic testing of assumptions towards best practices for precision and accuracy. PLANT, CELL & ENVIRONMENT 2022; 45:2037-2061. [PMID: 35394651 PMCID: PMC9322401 DOI: 10.1111/pce.14330] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 03/21/2022] [Accepted: 03/26/2022] [Indexed: 05/24/2023]
Abstract
Leaf water potential (ψleaf ), typically measured using the pressure chamber, is the most important metric of plant water status, providing high theoretical value and information content for multiple applications in quantifying critical physiological processes including drought responses. Pressure chamber measurements of ψleaf (ψleafPC ) are most typical, yet, the practical complexity of the technique and of the underlying theory has led to ambiguous understanding of the conditions to optimize measurements. Consequently, specific techniques and precautions diversified across the global research community, raising questions of reliability and repeatability. Here, we surveyed specific methods of ψleafPC from multiple laboratories, and synthesized experiments testing common assumptions and practices in ψleafPC for diverse species: (i) the need for equilibration of previously transpiring leaves; (ii) leaf storage before measurement; (iii) the equilibration of ψleaf for leaves on bagged branches of a range of dehydration; (iv) the equilibration of ψleaf across the lamina for bagged leaves, and the accuracy of measuring leaves with artificially 'elongated petioles'; (v) the need in ψleaf measurements for bagging leaves and high humidity within the chamber; (vi) the need to avoid liquid water on leaf surfaces; (vii) the use of 'pulse' pressurization versus gradual pressurization; and (viii) variation among experimenters in ψleafPC determination. Based on our findings we provide a best practice protocol to maximise accuracy, and provide recommendations for ongoing species-specific tests of important assumptions in future studies.
Collapse
Affiliation(s)
- Celia M. Rodriguez‐Dominguez
- Protection of the Soil, Plant, Water SystemIrrigation and Crop Ecophysiology Group, IRNAS‐CSICSevillaSpain
- Plant BiotechnologyLaboratory of Plant Molecular Ecophysiology, IRNAS‐CSICSevillaSpain
| | - Alicia Forner
- Department of Biogeography and Global Change, International Global Change Laboratory (LINCGlobal), Museo Nacional de Ciencias NaturalesConsejo Superior de Investigaciones CientíficasMadridSpain
- Department of Ecology, Centro de Investigaciones sobre Desertificación, Consejo Superior de Investigaciones Científicas (CSIC)University of València and Generalitat ValencianaValenciaSpain
| | - Sebastia Martorell
- Departament de Biologia, Research Group on Plant Biology under Mediterranean ConditionsUniversitat de les Illes BalearsPalma de MallorcaSpain
| | - Brendan Choat
- Plants, Animals and Interactions, Hawkesbury Institute for the EnvironmentWestern Sydney UniversityPenrithNew South WalesAustralia
| | - Rosana Lopez
- Departamento de Sistemas y Recursos NaturalesUniversidad Politécnica de MadridMadridSpain
| | - Jennifer M. R. Peters
- Division of Environmental Science, Oak Ridge National LaboratoryClimate Change Science InstituteOak RidgeTennesseeUSA
| | - Sebastian Pfautsch
- Geography, Tourism and Urban Planning, Urban Studies, School of Social Science and PsychologyWestern Sydney UniversityPenrithNew South WalesAustralia
| | - Stefan Mayr
- Department of BotanyUniversity of InnsbruckInnsbruckAustria
| | - Madeline R. Carins‐Murphy
- Plant Sciences, Discipline of Biological Sciences, School of Natural SciencesUniversity of TasmaniaHobartAustralia
| | - Scott A. M. McAdam
- Department of Botany and Plant Pathology, Purdue Center for Plant BiologyPurdue UniversityWest LafayetteIndianaUSA
| | - Freya Richardson
- Plant Sciences, Discipline of Biological Sciences, School of Natural SciencesUniversity of TasmaniaHobartAustralia
| | - Antonio Diaz‐Espejo
- Protection of the Soil, Plant, Water SystemIrrigation and Crop Ecophysiology Group, IRNAS‐CSICSevillaSpain
- Plant BiotechnologyLaboratory of Plant Molecular Ecophysiology, IRNAS‐CSICSevillaSpain
| | - Virginia Hernandez‐Santana
- Protection of the Soil, Plant, Water SystemIrrigation and Crop Ecophysiology Group, IRNAS‐CSICSevillaSpain
- Plant BiotechnologyLaboratory of Plant Molecular Ecophysiology, IRNAS‐CSICSevillaSpain
| | - Paulo E. Menezes‐Silva
- Laboratory of Integrative Physics and Physiology of Trees in a Fluctuating EnvironmentUniversité Clermont‐Auvergne, INRAE, PIAFClermont‐FerrandFrance
| | - Jose M. Torres‐Ruiz
- Laboratory of Integrative Physics and Physiology of Trees in a Fluctuating EnvironmentUniversité Clermont‐Auvergne, INRAE, PIAFClermont‐FerrandFrance
| | - Timothy A. Batz
- Department of Botany and Plant Pathology, Purdue Center for Plant BiologyPurdue UniversityWest LafayetteIndianaUSA
| | - Lawren Sack
- Department of Ecology and Evolutionary BiologyUniversity of CaliforniaLos AngelesCaliforniaUSA
| |
Collapse
|
19
|
Lamour J, Davidson KJ, Ely KS, Le Moguédec G, Leakey ADB, Li Q, Serbin SP, Rogers A. An improved representation of the relationship between photosynthesis and stomatal conductance leads to more stable estimation of conductance parameters and improves the goodness-of-fit across diverse data sets. GLOBAL CHANGE BIOLOGY 2022; 28:3537-3556. [PMID: 35090072 DOI: 10.1111/gcb.16103] [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: 06/30/2021] [Revised: 01/17/2022] [Accepted: 01/20/2022] [Indexed: 06/14/2023]
Abstract
Stomata play a central role in surface-atmosphere exchange by controlling the flux of water and CO2 between the leaf and the atmosphere. Representation of stomatal conductance (gsw ) is therefore an essential component of models that seek to simulate water and CO2 exchange in plants and ecosystems. For given environmental conditions at the leaf surface (CO2 concentration and vapor pressure deficit or relative humidity), models typically assume a linear relationship between gsw and photosynthetic CO2 assimilation (A). However, measurement of leaf-level gsw response curves to changes in A are rare, particularly in the tropics, resulting in only limited data to evaluate this key assumption. Here, we measured the response of gsw and A to irradiance in six tropical species at different leaf phenological stages. We showed that the relationship between gsw and A was not linear, challenging the key assumption upon which optimality theory is based-that the marginal cost of water gain is constant. Our data showed that increasing A resulted in a small increase in gsw at low irradiance, but a much larger increase at high irradiance. We reformulated the popular Unified Stomatal Optimization (USO) model to account for this phenomenon and to enable consistent estimation of the key conductance parameters g0 and g1 . Our modification of the USO model improved the goodness-of-fit and reduced bias, enabling robust estimation of conductance parameters at any irradiance. In addition, our modification revealed previously undetectable relationships between the stomatal slope parameter g1 and other leaf traits. We also observed nonlinear behavior between A and gsw in independent data sets that included data collected from attached and detached leaves, and from plants grown at elevated CO2 concentration. We propose that this empirical modification of the USO model can improve the measurement of gsw parameters and the estimation of plant and ecosystem-scale water and CO2 fluxes.
Collapse
Affiliation(s)
- Julien Lamour
- Environmental & Climate Sciences Department, Brookhaven National Laboratory, Upton, New York, USA
| | - Kenneth J Davidson
- Environmental & Climate Sciences Department, Brookhaven National Laboratory, Upton, New York, USA
- Department of Ecology and Evolution, Stony Brook University, Stony Brook, New York, USA
| | - Kim S Ely
- Environmental & Climate Sciences Department, Brookhaven National Laboratory, Upton, New York, USA
| | - Gilles Le Moguédec
- AMAP, Université Montpellier, INRAE, Cirad CNRS, IRD, Montpellier, France
| | - Andrew D B Leakey
- Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
- Department of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Qianyu Li
- Environmental & Climate Sciences Department, Brookhaven National Laboratory, Upton, New York, USA
| | - Shawn P Serbin
- Environmental & Climate Sciences Department, Brookhaven National Laboratory, Upton, New York, USA
| | - Alistair Rogers
- Environmental & Climate Sciences Department, Brookhaven National Laboratory, Upton, New York, USA
| |
Collapse
|
20
|
Manu R, Corre MD, Aleeje A, Mwanjalolo MJG, Babweteera F, Veldkamp E, van Straaten O. Responses of tree growth and biomass production to nutrient addition in a semi-deciduous tropical forest in Africa. Ecology 2022; 103:e3659. [PMID: 35129838 DOI: 10.1002/ecy.3659] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 09/24/2021] [Accepted: 10/25/2021] [Indexed: 11/11/2022]
Abstract
Experimental evidence of nutrient limitations on primary productivity in Afrotropical forests is rare and globally underrepresented, yet are crucial for understanding constraints to terrestrial carbon uptake. In an ecosystem-scale nutrient manipulation experiment, we assessed the early responses of tree growth rates among different tree sizes, taxonomic species and at a community level in a humid tropical forest in Uganda. Following a full factorial design, we established 32 (eight treatments × four replicates) experimental plots of 40 m × 40 m each. We added nitrogen (N), phosphorus (P), potassium (K), their combinations (NP, NK, PK, and NPK) and control at the rates of 125 kg N.ha-1 .yr-1 , 50 kg P.ha-1 .yr-1 and 50 kg K.ha-1 .yr-1 , split into four equal applications, and measured stem growth of more than 15,000 trees with diameter at breast height (DBH) ≥ 1 cm. After two years, the response of tree stem growth to nutrient additions was dependent on tree sizes, species and leaf habit but not community-wide. First, tree stem growth increased under N additions, primarily among medium-sized trees (10-30 cm DBH), and in trees of Lasiodiscus mildbraedii in the second year of the experiment. Second, K limitation was evident in semi-deciduous trees, which increased stem growth by 46% in +K than -K treatments, following a strong, prolonged dry season during the first year of the experiment. This highlights the key role of K in stomatal regulation and maintenance of water balance in trees, particularly under water-stressed conditions. Third, the role of P in promoting tree growth and carbon accumulation rates in this forest on highly weathered soils was rather not pronounced; nonetheless, mortality among saplings (1-5 cm DBH) was reduced by 30% in +P than in -P treatments. Although stem growth responses to nutrient interaction effects were positive or negative (likely depending on nutrient combinations and climate variability), our results underscore the fact that, in a highly diverse forest ecosystem, multiple nutrients and not one single nutrient regulate tree growth and aboveground carbon uptake due to varying nutrient requirements and acquisition strategies of different tree sizes, species and leaf habits.
Collapse
Affiliation(s)
- Raphael Manu
- Department of Soil Science of Tropical and Subtropical Ecosystems, Georg-August University of Goettingen, Buesgenweg 2, 37077, Goettingen, Germany
| | - Marife D Corre
- Department of Soil Science of Tropical and Subtropical Ecosystems, Georg-August University of Goettingen, Buesgenweg 2, 37077, Goettingen, Germany
| | - Alfred Aleeje
- Department of Agricultural Production, Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Majaliwa J G Mwanjalolo
- Department of Geography, Geo-informatics and Climate Sciences, Makerere University, P.O. Box 7062, Kampala, Uganda.,Regional FORUM for capacity building in Agriculture-RUFORUM, Kampala, Uganda
| | - Fred Babweteera
- Department of Forestry, Biodiversity and Tourism, Makerere University, P.O. Box 7062, Kampala, Uganda.,Budongo Conservation Field Station, P.O. Box 362, Masindi, Uganda
| | - Edzo Veldkamp
- Department of Soil Science of Tropical and Subtropical Ecosystems, Georg-August University of Goettingen, Buesgenweg 2, 37077, Goettingen, Germany
| | - Oliver van Straaten
- Department of Soil Science of Tropical and Subtropical Ecosystems, Georg-August University of Goettingen, Buesgenweg 2, 37077, Goettingen, Germany.,Johann Heinrich von Thuenen Institute, Institute for Forest Ecosystems, Alfred-Möller-Straße 1, Eberswalde, Germany
| |
Collapse
|
21
|
Li W, Zhang H, Wang W, Zhang P, Ward ND, Norwood M, Myers-Pigg A, Zhao C, Leff R, Yabusaki S, Waichler S, Bailey VL, McDowell NG. Changes in carbon and nitrogen metabolism during seawater-induced mortality of Picea sitchensis trees. TREE PHYSIOLOGY 2021; 41:2326-2340. [PMID: 34014270 DOI: 10.1093/treephys/tpab073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 05/13/2021] [Indexed: 05/13/2023]
Abstract
Increasing seawater exposure is causing mortality of coastal forests, yet the physiological response associated with seawater-induced tree mortality, particularly in non-halophytes, is poorly understood. We investigated the shifts in carbon and nitrogen (N) metabolism of mature Sitka-spruce trees that were dying after an ecosystem-scale manipulation of tidal seawater exposure. Soil porewater salinity and foliar ion concentrations increased after seawater exposure and were strongly correlated with the percentage of live foliated crown (PLFC; e.g., crown 'greenness', a measure of progression to death). Co-occurring with decreasing PLFC was decreasing photosynthetic capacity, N-investment into photosynthesis, N-resorption efficiency and non-structural carbohydrate (soluble sugars and starch) concentrations, with the starch reserves depleted to near zero when PLFC dropped below 5%. Combined with declining PLFC, these changes subsequently decreased total carbon gain and thus exacerbated the carbon starvation process. This study suggests that an impairment in carbon and N metabolism during the mortality process after seawater exposure is associated with the process of carbon starvation, and provides critical knowledge necessary to predict sea-level rise impacts on coastal forests.
Collapse
Affiliation(s)
- Weibin Li
- State Key Laboratory of Grassland and Agro-ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730020, China
- Atmospheric Sciences & Global Change Division, Pacific Northwest National Laboratory, Richland, Washington 99354, USA
- Key Laboratory of Geospatial Technology for Middle and Lower Yellow River Regions (Henan University), Ministry of Education, Kaifeng 475004, China
| | - Hongxia Zhang
- Atmospheric Sciences & Global Change Division, Pacific Northwest National Laboratory, Richland, Washington 99354, USA
- Shapotou Desert Research and Experiment Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Wenzhi Wang
- Atmospheric Sciences & Global Change Division, Pacific Northwest National Laboratory, Richland, Washington 99354, USA
| | - Peipei Zhang
- Atmospheric Sciences & Global Change Division, Pacific Northwest National Laboratory, Richland, Washington 99354, USA
- School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Nicholas D Ward
- Marine and Coastal Research Laboratory, Pacific Northwest National Laboratory, Sequim, Washington 98382, USA
- School of Oceanography, University of Washington, Seattle, Washington 98195, USA
| | - Matt Norwood
- Marine and Coastal Research Laboratory, Pacific Northwest National Laboratory, Sequim, Washington 98382, USA
| | - Allison Myers-Pigg
- Marine and Coastal Research Laboratory, Pacific Northwest National Laboratory, Sequim, Washington 98382, USA
| | - Chuanyan Zhao
- State Key Laboratory of Grassland and Agro-ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730020, China
| | - Riley Leff
- Atmospheric Sciences & Global Change Division, Pacific Northwest National Laboratory, Richland, Washington 99354, USA
| | - Steve Yabusaki
- Earth Systems Science, Pacific Northwest National Laboratory, Richland, Washington 99354, USA
| | - Scott Waichler
- Earth Systems Science, Pacific Northwest National Laboratory, Richland, Washington 99354, USA
| | - Vanessa L Bailey
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99354, USA
| | - Nate G McDowell
- Atmospheric Sciences & Global Change Division, Pacific Northwest National Laboratory, Richland, Washington 99354, USA
- School of Biological Sciences, Washington State University, Pullman, Washington 99164-4236, USA
| |
Collapse
|
22
|
Slot M, Nardwattanawong T, Hernández GG, Bueno A, Riederer M, Winter K. Large differences in leaf cuticle conductance and its temperature response among 24 tropical tree species from across a rainfall gradient. THE NEW PHYTOLOGIST 2021; 232:1618-1631. [PMID: 34270792 PMCID: PMC9290923 DOI: 10.1111/nph.17626] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 07/12/2021] [Indexed: 05/09/2023]
Abstract
More frequent droughts and rising temperatures pose serious threats to tropical forests. When stomata are closed under dry and hot conditions, plants lose water through leaf cuticles, but little is known about cuticle conductance (gmin ) of tropical trees, how it varies among species and environments, and how it is affected by temperature. We determined gmin in relation to temperature for 24 tropical tree species across a steep rainfall gradient in Panama, by recording leaf drying curves at different temperatures in the laboratory. In contrast with our hypotheses, gmin did not differ systematically across the rainfall gradient; species differences did not reflect phylogenetic patterns; and in most species gmin did not significantly increase between 25 and 50°C. gmin was higher in deciduous than in evergreen species, in species with leaf trichomes than in species without, in sun leaves than in shade leaves, and tended to decrease with increasing leaf mass per area across species. There was no relationship between stomatal and cuticle conductance. Large species differences in gmin and its temperature response suggest that more frequent hot droughts may lead to differential survival among tropical tree species, regardless of species' position on the rainfall gradient.
Collapse
Affiliation(s)
- Martijn Slot
- Smithsonian Tropical Research InstituteApartado 0843‐03092BalboaAncónRepublic of Panama
| | - Tantawat Nardwattanawong
- Smithsonian Tropical Research InstituteApartado 0843‐03092BalboaAncónRepublic of Panama
- University of East AngliaNorwichNR4 7TJUK
| | - Georgia G. Hernández
- Smithsonian Tropical Research InstituteApartado 0843‐03092BalboaAncónRepublic of Panama
| | - Amauri Bueno
- Julius‐von Sachs‐Institute for BiosciencesBotany IIUniversity of WürzburgJulius‐von‐Sachs‐Platz 3WürzburgD‐97082Germany
| | - Markus Riederer
- Julius‐von Sachs‐Institute for BiosciencesBotany IIUniversity of WürzburgJulius‐von‐Sachs‐Platz 3WürzburgD‐97082Germany
| | - Klaus Winter
- Smithsonian Tropical Research InstituteApartado 0843‐03092BalboaAncónRepublic of Panama
| |
Collapse
|
23
|
Zhang H, Li X, Wang W, Pivovaroff AL, Li W, Zhang P, Ward ND, Myers-Pigg A, Adams HD, Leff R, Wang A, Yuan F, Wu J, Yabusaki S, Waichler S, Bailey VL, Guan D, McDowell NG. Seawater exposure causes hydraulic damage in dying Sitka-spruce trees. PLANT PHYSIOLOGY 2021; 187:873-885. [PMID: 34608959 PMCID: PMC8981213 DOI: 10.1093/plphys/kiab295] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 06/09/2021] [Indexed: 05/29/2023]
Abstract
Sea-level rise is one of the most critical challenges facing coastal ecosystems under climate change. Observations of elevated tree mortality in global coastal forests are increasing, but important knowledge gaps persist concerning the mechanism of salinity stress-induced nonhalophytic tree mortality. We monitored progressive mortality and associated gas exchange and hydraulic shifts in Sitka-spruce (Picea sitchensis) trees located within a salinity gradient under an ecosystem-scale change of seawater exposure in Washington State, USA. Percentage of live foliated crown (PLFC) decreased and tree mortality increased with increasing soil salinity during the study period. A strong reduction in gas exchange and xylem hydraulic conductivity (Ks) occurred during tree death, with an increase in the percentage loss of conductivity (PLC) and turgor loss point (πtlp). Hydraulic and osmotic shifts reflected that hydraulic function declined from seawater exposure, and dying trees were unable to support osmotic adjustment. Constrained gas exchange was strongly related to hydraulic damage at both stem and leaf levels. Significant correlations between foliar sodium (Na+) concentration and gas exchange and key hydraulic parameters (Ks, PLC, and πtlp) suggest that cellular injury related to the toxic effects of ion accumulation impacted the physiology of these dying trees. This study provides evidence of toxic effects on the cellular function that manifests in all aspects of plant functioning, leading to unfavourable osmotic and hydraulic conditions.
Collapse
Affiliation(s)
- Hongxia Zhang
- Shapotou Desert Research and Experiment Station, Northwest Institute of
Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000,
China
- Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology,
Chinese Academy of Sciences, Shenyang 110016, China
- Atmospheric Sciences and Global Change Division, Pacific Northwest National
Laboratory, Richland, Washington 99354, USA
| | - Xinrong Li
- Shapotou Desert Research and Experiment Station, Northwest Institute of
Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000,
China
| | - Wenzhi Wang
- Atmospheric Sciences and Global Change Division, Pacific Northwest National
Laboratory, Richland, Washington 99354, USA
- The Key Laboratory of Mountain Environment Evolution and Regulation, Institute
of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu
610041, China
| | - Alexandria L. Pivovaroff
- Atmospheric Sciences and Global Change Division, Pacific Northwest National
Laboratory, Richland, Washington 99354, USA
| | - Weibin Li
- Atmospheric Sciences and Global Change Division, Pacific Northwest National
Laboratory, Richland, Washington 99354, USA
- State Key Laboratory of Grassland and Agro-ecosystems, Key Laboratory of
Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs,
College of Pastoral Agriculture Science and Technology, Lanzhou University,
Lanzhou 730020, China
| | - Peipei Zhang
- Atmospheric Sciences and Global Change Division, Pacific Northwest National
Laboratory, Richland, Washington 99354, USA
| | - Nicholas D. Ward
- Marine Sciences Laboratory, Pacific Northwest National
Laboratory, Sequim, Washington 98382, USA
- School of Oceanography, University of Washington, Seattle,
Washington 98195, USA
| | - Allison Myers-Pigg
- State Key Laboratory of Grassland and Agro-ecosystems, Key Laboratory of
Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs,
College of Pastoral Agriculture Science and Technology, Lanzhou University,
Lanzhou 730020, China
| | - Henry D. Adams
- School of the Environment, Washington State University, Pullman,
Washington 99164-2812, USA
| | - Riley Leff
- Atmospheric Sciences and Global Change Division, Pacific Northwest National
Laboratory, Richland, Washington 99354, USA
| | - Anzhi Wang
- Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology,
Chinese Academy of Sciences, Shenyang 110016, China
| | - Fenghui Yuan
- Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology,
Chinese Academy of Sciences, Shenyang 110016, China
| | - Jiabing Wu
- Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology,
Chinese Academy of Sciences, Shenyang 110016, China
| | - Steve Yabusaki
- Earth Systems Science, Pacific Northwest National Laboratory,
Richland, Washington 99354, USA
| | - Scott Waichler
- Earth Systems Science, Pacific Northwest National Laboratory,
Richland, Washington 99354, USA
| | - Vanessa L. Bailey
- Biological Sciences Division, Pacific Northwest National
Laboratory, Richland, Washington 99354, USA
| | - Dexin Guan
- Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology,
Chinese Academy of Sciences, Shenyang 110016, China
| | - Nate G. McDowell
- Atmospheric Sciences and Global Change Division, Pacific Northwest National
Laboratory, Richland, Washington 99354, USA
- School of Biological Sciences, Washington State University,
Pullman, Washington 99164-4236, USA
| |
Collapse
|
24
|
Du B, Zhu Y, Kang H, Liu C. Spatial variations in stomatal traits and their coordination with leaf traits in Quercus variabilis across Eastern Asia. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 789:147757. [PMID: 34058578 DOI: 10.1016/j.scitotenv.2021.147757] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 05/07/2021] [Accepted: 05/10/2021] [Indexed: 05/26/2023]
Abstract
The stomatal traits influence ecosystem carbon-water fluxes and play essential roles that enable plants to adapt to changing environmental conditions. However, how stomatal traits vary along a large climate gradient and whether stomatal traits coordinated with other leaf functional traits in response to environmental changes remain unclear. We investigated the stomatal density (SD), stomatal size (SS), and leaf traits (leaf area (LA), leaf mass per area (LMA), and vein density (VD)) of 44 in situ Quercus variabilis populations across Eastern Asia (24 to 51.8°N, 99 to 137°E) and 15 populations grown in a common garden, and evaluated their relationships with environmental factors. Stepwise multiple regression showed that the SD was significantly associated with mean annual precipitation (MAP), LMA, and VD, and the SS with latitude, mean annual temperature (MAT), mean monthly solar radiation (MMSR), and VD. The SD was positively correlated with the LMA, while the SS was negatively correlated with the VD. The SD and LMA increased with decreasing precipitation, which indicated that they may coordinate to commonly enhance plant resistance against drought. The SS decreased; however, the VD increased with temperature. This implied that plants might further reduce their SS by increasing VD limitations under global warming. In the common garden, plants exhibited a higher SD and VD and lower SS and LA compared to those in the field; however, no relation between the stomatal and leaf traits was observed. Our results suggested that stomatal traits have high environmental plasticity and are highly coordinated with other leaf functional traits in response to environmental changes. Nevertheless, this coordination may have been formed through long-term adaptations, rather than over short time spans.
Collapse
Affiliation(s)
- Baoming Du
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yanhua Zhu
- Instrumental Analysis Center, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hongzhang Kang
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China; School of Design, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Chunjiang Liu
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Urban Forest Ecosystem Research Station, State Forestry Administration, Shanghai 200240, China; Shanghai Yangtze River Delta Eco-environmental Change and Management Observation and Research Station, Ministry of Science and Technology, Shanghai 200240, China.
| |
Collapse
|
25
|
Burnett AC, Serbin SP, Lamour J, Anderson J, Davidson KJ, Yang D, Rogers A. Seasonal trends in photosynthesis and leaf traits in scarlet oak. TREE PHYSIOLOGY 2021; 41:1413-1424. [PMID: 33611562 DOI: 10.1093/treephys/tpab015] [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: 09/25/2020] [Accepted: 01/22/2021] [Indexed: 06/12/2023]
Abstract
Understanding seasonal variation in photosynthesis is important for understanding and modeling plant productivity. Here, we used shotgun sampling to examine physiological, structural and spectral leaf traits of upper canopy, sun-exposed leaves in Quercus coccinea Münchh (scarlet oak) across the growing season in order to understand seasonal trends, explore the mechanisms underpinning physiological change and investigate the impact of extrapolating measurements from a single date to the whole season. We tested the hypothesis that photosynthetic rates and capacities would peak at the summer solstice, i.e., at the time of peak photoperiod. Contrary to expectations, our results reveal a late-season peak in both photosynthetic capacity and rate before the expected sharp decrease at the start of senescence. This late-season maximum occurred after the higher summer temperatures and vapor pressure deficit and was correlated with the recovery of leaf water content and increased stomatal conductance. We modeled photosynthesis at the top of the canopy and found that the simulated results closely tracked the maximum carboxylation capacity of Rubisco. For both photosynthetic capacity and modeled top-of-canopy photosynthesis, the maximum value was therefore not observed at the summer solstice. Rather, in each case, the measurements at and around the solstice were close to the overall seasonal mean, with values later in the season leading to deviations from the mean by up to 41 and 52%, respectively. Overall, we found that the expected Gaussian pattern of photosynthesis was not observed. We conclude that an understanding of species- and environment-specific changes in photosynthesis across the season is essential for correct estimation of seasonal photosynthetic capacity.
Collapse
Affiliation(s)
- Angela C Burnett
- Environmental and Climate Sciences Department, Brookhaven National Laboratory, Upton, NY 11973, USA
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK
| | - Shawn P Serbin
- Environmental and Climate Sciences Department, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Julien Lamour
- Environmental and Climate Sciences Department, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Jeremiah Anderson
- Environmental and Climate Sciences Department, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Kenneth J Davidson
- Environmental and Climate Sciences Department, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Dedi Yang
- Environmental and Climate Sciences Department, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Alistair Rogers
- Environmental and Climate Sciences Department, Brookhaven National Laboratory, Upton, NY 11973, USA
| |
Collapse
|
26
|
Xu X, Konings AG, Longo M, Feldman A, Xu L, Saatchi S, Wu D, Wu J, Moorcroft P. Leaf surface water, not plant water stress, drives diurnal variation in tropical forest canopy water content. THE NEW PHYTOLOGIST 2021; 231:122-136. [PMID: 33539544 DOI: 10.1111/nph.17254] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Accepted: 01/27/2021] [Indexed: 05/25/2023]
Abstract
Variation in canopy water content (CWC) that can be detected from microwave remote sensing of vegetation optical depth (VOD) has been proposed as an important measure of vegetation water stress. However, the contribution of leaf surface water (LWs ), arising from dew formation and rainfall interception, to CWC is largely unknown, particularly in tropical forests and other high-humidity ecosystems. We compared VOD data from the Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR-E) and CWC predicted by a plant hydrodynamics model at four tropical sites in Brazil spanning a rainfall gradient. We assessed how LWs influenced the relationship between VOD and CWC. The analysis indicates that while CWC is strongly correlated with VOD (R2 = 0.62 across all sites), LWs accounts for 61-76% of the diurnal variation in CWC despite being < 10% of CWC. Ignoring LWs weakens the near-linear relationship between CWC and VOD and reduces the consistency in diurnal variation. The contribution of LWs to CWC variation, however, decreases at longer, seasonal to inter-annual, time scales. Our results demonstrate that diurnal patterns of dew formation and rainfall interception can be an important driver of diurnal variation in CWC and VOD over tropical ecosystems and therefore should be accounted for when inferring plant diurnal water stress from VOD measurements.
Collapse
Affiliation(s)
- Xiangtao Xu
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, 14850, USA
| | - Alexandra G Konings
- Department of Earth System Science, Stanford University, Stanford, CA, 94305, USA
| | - Marcos Longo
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, 91109, USA
| | - Andrew Feldman
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Liang Xu
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, 91109, USA
| | - Sassan Saatchi
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, 91109, USA
- Institute of Environment and Sustainability, University of California, Los Angeles, CA, 90024, USA
| | - Donghai Wu
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, 14850, USA
| | - Jin Wu
- School of Biological Sciences, University of Hong Kong, Hong Kong, China
| | - Paul Moorcroft
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
| |
Collapse
|
27
|
Ayyaz A, Miao Y, Hannan F, Islam F, Zhang K, Xu J, Farooq MA, Zhou W. Drought tolerance in Brassica napus is accompanied with enhanced antioxidative protection, photosynthetic and hormonal regulation at seedling stage. PHYSIOLOGIA PLANTARUM 2021; 172:1133-1148. [PMID: 33599291 DOI: 10.1111/ppl.13375] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 01/09/2021] [Accepted: 02/15/2021] [Indexed: 06/12/2023]
Abstract
Climate change, food insecurity, water scarcity, and population growth are some of today's world's frightening problems. Drought stress exerts a constant threat to field crops and is often seen as a major constraint on global agricultural productivity; its intensity and frequency are expected to increase in the near future. The present study investigated the effects of drought stress (15% w/v polyethylene glycol PEG-6000) on physiological and biochemical changes in five Brassica napus cultivars (ZD630, ZD622, ZD619, GY605, and ZS11). For drought stress induction, 3-week-old rapeseed oil seedlings were treated with PEG-6000 in full strength Hoagland nutrient solution for 7 days. PEG treatment significantly decreased the plant growth and photosynthetic efficiency, including primary photochemistry (Fv/Fm) of PSII, intercellular CO2 , net photosynthesis, chlorophyll contents, and water-use efficiency of all studied B. napus cultivars; however, pronounced growth retardations were observed in cultivar GY605. Drought-stressed B. napus cultivars also experienced a sharp rise in H2 O2 generation and malondialdehyde (MDA) content. Additionally, the accumulation of ROS was accompanied by increased activity of enzymatic antioxidants (superoxide dismutase, peroxidase, catalase, ascorbate peroxidase, glutathione reductase, and monodehydroascorbate reductase), although the increase was more obvious in ZD622 and ZS11. Drought stress also caused an increased endogenous hormonal biosynthesis (abscisic acid, jasmonic acid, salicylic acid) and accumulation of total soluble proteins and proline content, but the extent varies in B. napus cultivars. These results suggest that B. napus cultivars have an efficient drought stress tolerance mechanism, as shown by improved antioxidant enzyme activities, photosynthetic and hormonal regulation.
Collapse
Affiliation(s)
- Ahsan Ayyaz
- Institute of Crop Science, Ministry of Agriculture and Rural Affairs Laboratory of Spectroscopy Sensing, Zhejiang University, Hangzhou, China
| | - Yilin Miao
- Institute of Crop Science, Ministry of Agriculture and Rural Affairs Laboratory of Spectroscopy Sensing, Zhejiang University, Hangzhou, China
| | - Fakhir Hannan
- Institute of Crop Science, Ministry of Agriculture and Rural Affairs Laboratory of Spectroscopy Sensing, Zhejiang University, Hangzhou, China
| | - Faisal Islam
- Institute of Crop Science, Ministry of Agriculture and Rural Affairs Laboratory of Spectroscopy Sensing, Zhejiang University, Hangzhou, China
| | - Kangni Zhang
- Institute of Crop Science, Ministry of Agriculture and Rural Affairs Laboratory of Spectroscopy Sensing, Zhejiang University, Hangzhou, China
| | - Jianxiang Xu
- Institute of Crop Science, Quzhou Academy of Agricultural Sciences, Quzhou, China
| | - Muhammad Ahsan Farooq
- Institute of Crop Science, Ministry of Agriculture and Rural Affairs Laboratory of Spectroscopy Sensing, Zhejiang University, Hangzhou, China
| | - Weijun Zhou
- Institute of Crop Science, Ministry of Agriculture and Rural Affairs Laboratory of Spectroscopy Sensing, Zhejiang University, Hangzhou, China
| |
Collapse
|
28
|
Importance of hydraulic strategy trade-offs in structuring response of canopy trees to extreme drought in central Amazon. Oecologia 2021; 197:13-24. [PMID: 33948691 DOI: 10.1007/s00442-021-04924-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 04/21/2021] [Indexed: 10/21/2022]
Abstract
Plant ecophysiological trade-offs between different strategies for tolerating stresses are widely theorized to shape forest functional diversity and vulnerability to climate change. However, trade-offs between hydraulic and stomatal regulation during natural droughts remain under-studied, especially in tropical forests. We investigated eleven mature forest canopy trees in central Amazonia during the strong 2015 El Niño. We found greater xylem embolism resistance ([Formula: see text] = - 3.3 ± 0.8 MPa) and hydraulic safety margin (HSM = 2.12 ± 0.57 MPa) than previously observed in more precipitation-seasonal rainforests of eastern Amazonia and central America. We also discovered that taller trees exhibited lower embolism resistance and greater stomatal sensitivity, a height-structured trade-off between hydraulic resistance and active stomatal regulation. Such active regulation of tree water status, triggered by the onset of stem embolism, acted as a feedback to avoid further increases in embolism, and also explained declines in photosynthesis and transpiration. These results suggest that canopy trees exhibit a conservative hydraulic strategy to endure drought, with trade-offs between investment in xylem to reduce vulnerability to hydraulic failure, and active stomatal regulation to protect against low water potentials. These findings improve our understanding of strategies in tropical forest canopies and contribute to more accurate prediction of drought responses.
Collapse
|
29
|
Sample Identifiers and Metadata to Support Data Management and Reuse in Multidisciplinary Ecosystem Sciences. DATA SCIENCE JOURNAL 2021. [DOI: 10.5334/dsj-2021-011] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
|
30
|
Blonder B, Escobar S, Kapás RE, Michaletz ST. Low predictability of energy balance traits and leaf temperature metrics in desert, montane and alpine plant communities. Funct Ecol 2020. [DOI: 10.1111/1365-2435.13643] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Benjamin Blonder
- Rocky Mountain Biological Laboratory Crested Butte CO USA
- Environmental Change Institute School of Geography and the Environment University of Oxford Oxford UK
- Department of Environmental Science, Policy, and Management University of California Berkeley CA USA
| | | | - Rozália E. Kapás
- Rocky Mountain Biological Laboratory Crested Butte CO USA
- Department of Physical Geography Stockholm University Stockholm Sweden
| | - Sean T. Michaletz
- Rocky Mountain Biological Laboratory Crested Butte CO USA
- Earth and Environmental Sciences Division Los Alamos National Laboratory Los Alamos NM USA
- Department of Botany and Biodiversity Research Centre University of British Columbia Vancouver BC Canada
| |
Collapse
|
31
|
Aparecido LMT, Woo S, Suazo C, Hultine KR, Blonder B. High water use in desert plants exposed to extreme heat. Ecol Lett 2020; 23:1189-1200. [PMID: 32436365 DOI: 10.1111/ele.13516] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 03/22/2020] [Accepted: 03/25/2020] [Indexed: 01/06/2023]
Abstract
Many plant water use models predict leaves maximize carbon assimilation while minimizing water loss via transpiration. Alternate scenarios may occur at high temperature, including heat avoidance, where leaves increase water loss to evaporatively cool regardless of carbon uptake; or heat failure, where leaves non-adaptively lose water also regardless of carbon uptake. We hypothesized that these alternative scenarios are common in species exposed to hot environments, with heat avoidance more common in species with high construction cost leaves. Diurnal measurements of leaf temperature and gas exchange for 11 Sonoran Desert species revealed that 37% of these species increased transpiration in the absence of increased carbon uptake. High leaf mass per area partially predicted this behaviour (r2 = 0.39). These data are consistent with heat avoidance and heat failure, but failure is less likely given the ecological dominance of the focal species. These behaviours are not yet captured in any extant plant water use model.
Collapse
Affiliation(s)
- Luiza M T Aparecido
- School of Life Sciences, Arizona State University, 427 E Tyler Mall, Tempe, AZ, 85821, USA
| | - Sabrina Woo
- School of Life Sciences, Arizona State University, 427 E Tyler Mall, Tempe, AZ, 85821, USA
| | - Crystal Suazo
- School of Life Sciences, Arizona State University, 427 E Tyler Mall, Tempe, AZ, 85821, USA
| | - Kevin R Hultine
- Department of Research, Conservation and Collections, Desert Botanical Garden, 1201 N. Galvin Parkway, Phoenix, AZ, 85008, USA
| | - Benjamin Blonder
- School of Life Sciences, Arizona State University, 427 E Tyler Mall, Tempe, AZ, 85821, USA.,Environmental Change Institute, School of Geography and the Environment, University of Oxford, South Parks Road, Oxford, OX1 3QY, UK.,Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA, 94720, USA
| |
Collapse
|