1
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Belovitch MW, NeSmith JE, Nippert JB, Holdo RM. African savanna grasses outperform trees across the full spectrum of soil moisture availability. THE NEW PHYTOLOGIST 2023; 239:66-74. [PMID: 36967595 DOI: 10.1111/nph.18909] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 03/20/2023] [Indexed: 06/02/2023]
Abstract
Models of tree-grass coexistence in savannas make different assumptions about the relative performance of trees and grasses under wet vs dry conditions. We quantified transpiration and drought tolerance traits in 26 tree and 19 grass species from the African savanna biome across a gradient of soil water potentials to test for a trade-off between water use under wet conditions and drought tolerance. We measured whole-plant hourly transpiration in a growth chamber and quantified drought tolerance using leaf osmotic potential (Ψosm ). We also quantified whole-plant water-use efficiency (WUE) and relative growth rate (RGR) under well-watered conditions. Grasses transpired twice as much as trees on a leaf-mass basis across all soil water potentials. Grasses also had a lower Ψosm than trees, indicating higher drought tolerance in the former. Higher grass transpiration and WUE combined to largely explain the threefold RGR advantage in grasses. Our results suggest that grasses outperform trees under a wide range of conditions, and that there is no evidence for a trade-off in water-use patterns in wet vs dry soils. This work will help inform mechanistic models of water use in savanna ecosystems, providing much-needed whole-plant parameter estimates for African species.
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Affiliation(s)
| | | | - Jesse B Nippert
- Division of Biology, Kansas State University, Manhattan, KS, 66506, USA
| | - Ricardo M Holdo
- Odum School of Ecology, University of Georgia, Athens, GA, 30601, USA
- School of Animal Plant and Environmental Sciences, University of the Witwatersrand, Johannesburg, 2050, South Africa
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2
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Jacob V, Choat B, Churchill AC, Zhang H, Barton CVM, Krishnananthaselvan A, Post AK, Power SA, Medlyn BE, Tissue DT. High safety margins to drought-induced hydraulic failure found in five pasture grasses. PLANT, CELL & ENVIRONMENT 2022; 45:1631-1646. [PMID: 35319101 DOI: 10.1111/pce.14318] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 02/13/2022] [Accepted: 03/16/2022] [Indexed: 06/14/2023]
Abstract
Determining the relationship between reductions in stomatal conductance (gs ) and leaf water transport during dehydration is key to understanding plant drought responses. While numerous studies have analysed the hydraulic function of woody species, minimal research has been conducted on grasses. Here, we sought to characterize hydraulic vulnerability in five widely-occurring pasture grasses (including both C3 and C4 grasses) and determine whether reductions in gs and leaf hydraulic conductance (Kleaf ) during dehydration could be attributed to xylem embolism. Using the optical vulnerability (OV) technique, we found that all species were highly resistant to xylem embolism when compared to other herbaceous angiosperms, with 50% xylem embolism (PX50 ) occurring at xylem pressures ranging from -4.4 to -6.1 MPa. We observed similar reductions in gs and Kleaf under mild water stress for all species, occurring well before PX50 . The onset of xylem embolism (PX12 ) occurred consistently after stomatal closure and 90% reduction of Kleaf . Our results suggest that factors other than xylem embolism are responsible for the majority of reductions in gs and Kleaf during drought and reductions in the productivity of pasture species under moderate drought may not be driven by embolism.
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Affiliation(s)
- Vinod Jacob
- Western Sydney University, Penrith, New South Wales, Australia
| | - Brendan Choat
- Western Sydney University, Penrith, New South Wales, Australia
| | | | - Haiyang Zhang
- Western Sydney University, Penrith, New South Wales, Australia
| | | | | | - Alison K Post
- Department of Biology, Colorado State University, Fort Collins, Colorado, USA
| | - Sally A Power
- Western Sydney University, Penrith, New South Wales, Australia
| | | | - David T Tissue
- Western Sydney University, Penrith, New South Wales, Australia
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3
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Novick KA, Ficklin DL, Baldocchi D, Davis KJ, Ghezzehei TA, Konings AG, MacBean N, Raoult N, Scott RL, Shi Y, Sulman BN, Wood JD. Confronting the water potential information gap. NATURE GEOSCIENCE 2022; 15:158-164. [PMID: 35300262 PMCID: PMC8923290 DOI: 10.1038/s41561-022-00909-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 02/02/2022] [Indexed: 06/14/2023]
Abstract
Water potential directly controls the function of leaves, roots, and microbes, and gradients in water potential drive water flows throughout the soil-plant-atmosphere continuum. Notwithstanding its clear relevance for many ecosystem processes, soil water potential is rarely measured in-situ, and plant water potential observations are generally discrete, sparse, and not yet aggregated into accessible databases. These gaps limit our conceptual understanding of biophysical responses to moisture stress and inject large uncertainty into hydrologic and land surface models. Here, we outline the conceptual and predictive gains that could be made with more continuous and discoverable observations of water potential in soils and plants. We discuss improvements to sensor technologies that facilitate in situ characterization of water potential, as well as strategies for building new networks that aggregate water potential data across sites. We end by highlighting novel opportunities for linking more representative site-level observations of water potential to remotely-sensed proxies. Together, these considerations offer a roadmap for clearer links between ecohydrological processes and the water potential gradients that have the 'potential' to substantially reduce conceptual and modeling uncertainties.
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Affiliation(s)
- Kimberly A. Novick
- O’Neill School of Public and Environmental Affairs, Indiana University – Bloomington. Bloomington, IN USA
| | - Darren L. Ficklin
- Department of Geography, Indiana University – Bloomington. Bloomington, IN USA
| | - Dennis Baldocchi
- Department of Environmental Science, Policy, and Management. University of California, Berkeley. Berkeley, CA, USA
| | - Kenneth J. Davis
- Department of Meteorology and Atmospheric Science and Earth and Environmental Systems Institute, The Pennsylvania State University, University Park, PA, USA
| | - Teamrat A. Ghezzehei
- Life and Environmental Sciences Department, University of California – Merced. Merced, CA, USA
| | | | - Natasha MacBean
- Department of Geography, Indiana University – Bloomington. Bloomington, IN USA
| | - Nina Raoult
- Laboratoire des Sciences du Climat et de l’Environnement. Paris, France
| | - Russell L. Scott
- Southwest Watershed Research Center, USDA – Agricultural Research Service. Tucson, AZ, USA
| | - Yuning Shi
- Department of Plant Science. The Pennsylvania State University, University Park, PA, USA
| | - Benjamin N. Sulman
- Environmental Sciences Division, Oak Ridge National Laboratory. Oak Ridge, TN, USA
| | - Jeffrey D. Wood
- School of Natural Resources, University of Missouri, Columbia, MO, USA
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4
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O'Keefe K, Bachle S, Keen R, Tooley EG, Nippert JB. Root traits reveal safety and efficiency differences in grasses and shrubs exposed to different fire regimes. Funct Ecol 2021. [DOI: 10.1111/1365-2435.13972] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Kimberly O'Keefe
- Division of Biological Sciences Saint Edward's University Austin TX USA
- Department of Botany University of Wisconsin Madison WI USA
| | - Seton Bachle
- Division of Biology Kansas State University Manhattan KS USA
| | - Rachel Keen
- Division of Biology Kansas State University Manhattan KS USA
| | - E. Greg Tooley
- Division of Biology Kansas State University Manhattan KS USA
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5
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Wedel ER, O’Keefe K, Nippert JB, Hoch B, O’Connor RC. Spatio-temporal differences in leaf physiology are associated with fire, not drought, in a clonally integrated shrub. AOB PLANTS 2021; 13:plab037. [PMID: 34336177 PMCID: PMC8317628 DOI: 10.1093/aobpla/plab037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 06/08/2021] [Indexed: 06/13/2023]
Abstract
In highly disturbed environments, clonality facilitates plant survival via resprouting after disturbance, resource sharing among interconnected stems and vegetative reproduction. These traits likely contribute to the encroachment of deep-rooted clonal shrubs in tallgrass prairie. Clonal shrubs have access to deep soil water and are typically thought of as relatively insensitive to environmental variability. However, how leaf physiological traits differ among stems within individual clonal shrubs (hereafter 'intra-clonal') in response to extreme environmental variation (i.e. drought or fire) is unclear. Accounting for intra-clonal differences among stems in response to disturbance is needed to more accurately parameterize models that predict the effects of shrub encroachment on ecosystem processes. We assessed intra-clonal leaf-level physiology of the most dominant encroaching shrub in Kansas tallgrass prairie, Cornus drummondii, in response to precipitation and fire. We compared leaf gas exchange rates from the periphery to centre within shrub clones during a wet (2015) and extremely dry (2018) year. We also compared leaf physiology between recently burned shrubs (resprouts) with unburned shrubs in 2018. Resprouts had higher gas exchange rates and leaf nitrogen content than unburned shrubs, suggesting increased rates of carbon gain can contribute to recovery after fire. In areas recently burned, resprouts had higher gas exchange rates in the centre of the shrub than the periphery. In unburned areas, leaf physiology remained constant across the growing season within clonal shrubs (2015 and 2018). Results suggest single measurements within a shrub are likely sufficient to parameterize models to understand the effects of shrub encroachment on ecosystem carbon and water cycles, but model parameterization may require additional complexity in the context of fire.
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Affiliation(s)
- Emily R Wedel
- Division of Biology, Kansas State University, 116 Ackert Hall, Manhattan, KS 66502, USA
| | - Kimberly O’Keefe
- Department of Botany, University of Wisconsin, Madison, WI 53706, USA
| | - Jesse B Nippert
- Division of Biology, Kansas State University, 116 Ackert Hall, Manhattan, KS 66502, USA
| | - Braden Hoch
- Plant Protection and Weed Control Program, Kansas Department of Agriculture, Manhattan, KS 66502, USA
| | - Rory C O’Connor
- USDA-Agricultural Research Service, Eastern Oregon Agricultural Research Center, 67826-A Hwy 205, Burns, OR 97720, USA
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6
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Bachle S, Nippert JB. Microanatomical traits track climate gradients for a dominant C4 grass species across the Great Plains, USA. ANNALS OF BOTANY 2021; 127:451-459. [PMID: 32780105 PMCID: PMC7988519 DOI: 10.1093/aob/mcaa146] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 08/03/2020] [Indexed: 05/22/2023]
Abstract
BACKGROUND AND AIMS Andropogon gerardii is a highly productive C4 grass species with a large geographic range throughout the North American Great Plains, a biome characterized by a variable temperate climate. Plant traits are often invoked to explain growth rates and competitive abilities within broad climate gradients. For example, plant competition models typically predict that species with large geographic ranges benefit from variation in traits underlying high growth potential. Here, we examined the relationship between climate variability and leaf-level traits in A. gerardii, emphasizing how leaf-level microanatomical traits serve as a mechanism that may underlie variation in commonly measured traits, such as specific leaf area (SLA). METHODS Andropogon gerardii leaves were collected in August 2017 from Cedar Creek Ecosystem Science Reserve (MN), Konza Prairie Biological Station (KS), Platte River Prairie (NE) and Rocky Mountain Research Station (SD). Leaves from ten individuals from each site were trimmed, stained and prepared for fluorescent confocal microscopy to analyse internal leaf anatomy. Leaf microanatomical data were compared with historical and growing season climate data extracted from PRISM spatial climate models. KEY RESULTS Microanatomical traits displayed large variation within and across sites. According to AICc (Akaike's information criterion adjusted for small sample sizes) selection scores, the interaction of mean precipitation and temperature for the 2017 growing season was the best predictor of variability for the anatomical and morphological traits measured here. Mesophyll area and bundle sheath thickness were directly correlated with mean temperature (annual and growing season). Tissues related to water-use strategies, such as bulliform cell and xylem area, were significantly correlated with one another. CONCLUSIONS The results indicate that (1) microanatomical trait variation exists within this broadly distributed grass species, (2) microanatomical trait variability appears likely to impact leaf-level carbon and water use strategies, and (3) microanatomical trait values vary across climate gradients, and may underlie variation in traits measured at larger ecological scales.
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Affiliation(s)
- Seton Bachle
- Division of Biology, Kansas State University, Manhattan, KS, USA
- For correspondence. E-mail
| | - Jesse B Nippert
- Division of Biology, Kansas State University, Manhattan, KS, USA
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7
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Chieppa J, Brown T, Giresi P, Juenger TE, Resco de Dios V, Tissue DT, Aspinwall MJ. Climate and stomatal traits drive covariation in nighttime stomatal conductance and daytime gas exchange rates in a widespread C 4 grass. THE NEW PHYTOLOGIST 2021; 229:2020-2034. [PMID: 33037633 DOI: 10.1111/nph.16987] [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: 05/21/2020] [Accepted: 09/25/2020] [Indexed: 06/11/2023]
Abstract
Nighttime stomatal conductance (gsn ) varies among plant functional types and species, but factors shaping the evolution of gsn remain unclear. Examinations of intraspecific variation in gsn as a function of climate and co-varying leaf traits may provide new insight into the evolution of gsn and its adaptive significance. We grew 11 genotypes of Panicum virgatum (switchgrass) representing differing home-climates in a common garden experiment and measured nighttime and daytime leaf gas exchange, as well as stomatal density (SD) and size during early-, mid-, and late-summer. We used piecewise structural equation modelling to determine direct and indirect relationships between home-climate, gas exchange, and stomatal traits. We found no direct relationship between home-climate and gsn . However, genotypes from hotter climates possessed higher SD, which resulted in higher gsn . Across genotypes, higher gsn was associated with higher daytime stomatal conductance and net photosynthesis. Our results indicate that higher gsn may arise in genotypes from hotter climates via increased SD. High SD may provide benefits to genotypes from hotter climates through enhanced daytime transpirational cooling or by permitting maximal gas exchange when conditions are suitable. These results highlight the role of climate and trait coordination in shaping genetic differentiation in gsn .
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Affiliation(s)
- Jeff Chieppa
- Department of Biology, University of North Florida, Jacksonville, FL, 32224, USA
- School of Forestry and Wildlife Sciences, Auburn University, Auburn, AL, 36849, USA
| | - Tia Brown
- Department of Biology, Haverford College, Haverford, PA, 19041, USA
| | - Presley Giresi
- Department of Biology, University of North Florida, Jacksonville, FL, 32224, USA
| | - Thomas E Juenger
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, 78717, USA
| | - Víctor Resco de Dios
- School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, 621010, China
| | - David T Tissue
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW, 2753, Australia
| | - Michael J Aspinwall
- Department of Biology, University of North Florida, Jacksonville, FL, 32224, USA
- School of Forestry and Wildlife Sciences, Auburn University, Auburn, AL, 36849, USA
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8
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Collins SL, Nippert JB, Blair JM, Briggs JM, Blackmore P, Ratajczak Z. Fire frequency, state change and hysteresis in tallgrass prairie. Ecol Lett 2021; 24:636-647. [DOI: 10.1111/ele.13676] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 09/23/2020] [Accepted: 12/09/2020] [Indexed: 01/30/2023]
Affiliation(s)
- Scott L. Collins
- Department of Biology University of New Mexico Albuquerque NM87131USA
| | - Jesse B. Nippert
- Division of Biology Kansas State University Manhattan KS66506USA
| | - John M. Blair
- Division of Biology Kansas State University Manhattan KS66506USA
| | - John M. Briggs
- Division of Biology Kansas State University Manhattan KS66506USA
| | - Pamela Blackmore
- Division of Biology Kansas State University Manhattan KS66506USA
| | - Zak Ratajczak
- Division of Biology Kansas State University Manhattan KS66506USA
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9
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Sadok W, Jagadish SVK. The Hidden Costs of Nighttime Warming on Yields. TRENDS IN PLANT SCIENCE 2020; 25:644-651. [PMID: 32526169 DOI: 10.1016/j.tplants.2020.02.003] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 02/05/2020] [Accepted: 02/06/2020] [Indexed: 05/18/2023]
Abstract
Nighttime warming poses a threat to global food security as it is driving yield declines worldwide, but our understanding of the physiological basis of this phenomenon remains very limited. Furthermore, it is often assumed that such declines are driven solely by increases in nighttime temperature (TNight). Here we argue that, in addition to temperature, increases in nighttime evaporative demand may 'conspire' to penalize yields and end-use quality traits. We propose an ecophysiological framework outlining the possible mechanistic basis of such declines in yield and quality. We suggest ways to use the proposed framework as a guide to future efforts aimed at alleviating productivity losses by integrating crop ecophysiology with modeling, breeding, and management.
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Affiliation(s)
- Walid Sadok
- Department of Agronomy and Plant Genetics, University of Minnesota Twin Cities, MN, USA.
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10
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Resco de Dios V, Chowdhury FI, Granda E, Yao Y, Tissue DT. Assessing the potential functions of nocturnal stomatal conductance in C 3 and C 4 plants. THE NEW PHYTOLOGIST 2019; 223:1696-1706. [PMID: 31055839 DOI: 10.1111/nph.15881] [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: 03/27/2019] [Accepted: 04/24/2019] [Indexed: 05/16/2023]
Abstract
Nocturnal stomatal conductance contributes to water loss at night without carbon gain in C3 or C4 plants because photosynthesis does not occur in the dark. The functional relevance of nocturnal conductance thus remains an unresolved conundrum. Here, we review and re-analyse previously published datasets on nocturnal conductance (gn ) globally (176 species) to synthesize our current understanding on its potential biological function and to identify remaining research gaps. We found that gn was positively correlated with relative growth rate, which is compatible with the postulate that circadian-driven nocturnal conductance enhances predawn stomatal conductance, thereby priming stomata for photosynthesis in early daylight. The variation in gn across plant species and functional types was not consistent with the hypotheses that the main function of gn is to: remove excess CO2, which might limit growth; enhance oxygen delivery to the functional sapwood; enhance nutrient supply; or that gn is due to stomatal leakiness. We suggest further study regarding the potential of gn to be an important functional and ecological trait influencing competitive outcomes and we outline a research programme to achieve that objective.
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Affiliation(s)
- Víctor Resco de Dios
- School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, 621010, China
- Department of Crop and Forest Sciences & Agrotecnio Center, Universitat de Lleida, Lleida, 25198, Spain
| | - Faqrul I Chowdhury
- Master Course Mediterranean Forestry and Natural Resources Management, Universitat de Lleida, Lleida, 25198, Spain
| | - Elena Granda
- Department of Crop and Forest Sciences & Agrotecnio Center, Universitat de Lleida, Lleida, 25198, Spain
| | - Yinan Yao
- School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, 621010, China
| | - David T Tissue
- Hawkesbury Institute for the Environment, Western Sydney University, Hawkesbury Campus, Richmond, NSW, 2753, Australia
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11
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Yu K, Goldsmith GR, Wang Y, Anderegg WRL. Phylogenetic and biogeographic controls of plant nighttime stomatal conductance. THE NEW PHYTOLOGIST 2019; 222:1778-1788. [PMID: 30779147 DOI: 10.1111/nph.15755] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 02/03/2019] [Indexed: 06/09/2023]
Abstract
The widely documented phenomenon of nighttime stomatal conductance gsn could lead to substantial water loss with no carbon gain, and thus it remains unclear whether nighttime stomatal conductance confers a functional advantage. Given that studies of gsn have focused on controlled environments or small numbers of species in natural environments, a broad phylogenetic and biogeographic context could provide insights into potential adaptive benefits of gsn . We measured gsn on a diverse suite of species (n = 73) across various functional groups and climates-of-origin in a common garden to study the phylogenetic and biogeographic/climatic controls on gsn and further assessed the degree to which gsn co-varied with leaf functional traits and daytime gas-exchange rates. Closely related species were more similar in gsn than expected by chance. Herbaceous species had higher gsn than woody species. Species that typically grow in climates with lower mean annual precipitation - where the fitness cost of water loss should be the highest - generally had higher gsn . Our results reveal the highest gsn rates in species from environments where neighboring plants compete most strongly for water, suggesting a possible role for the competitive advantage of gsn .
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Affiliation(s)
- Kailiang Yu
- School of Biological Sciences, University of Utah, Salt Lake City, UT, 84112, USA
| | - Gregory R Goldsmith
- Schmid College of Science and Technology, Chapman University, Orange, CA, 92866, USA
| | - Yujie Wang
- School of Biological Sciences, University of Utah, Salt Lake City, UT, 84112, USA
| | - William R L Anderegg
- School of Biological Sciences, University of Utah, Salt Lake City, UT, 84112, USA
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12
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Abstract
The existence of a synthetic program of research on what was then termed the "nocturnal problem" and that we might now call "nighttime ecology" was declared more than 70 years ago. In reality, this failed to materialize, arguably as a consequence of practical challenges in studying organisms at night and instead concentrating on the existence of circadian rhythms, the mechanisms that give rise to them, and their consequences. This legacy is evident to this day, with consideration of the ecology of the nighttime markedly underrepresented in ecological research and literature. However, several factors suggest that it would be timely to revive the vision of a comprehensive research program in nighttime ecology. These include (i) that the study of the ecology of the night is being revolutionized by new and improved technologies; (ii) suggestions that, far from being a minor component of biodiversity, a high proportion of animal species are active at night; (iii) that fundamental questions about differences and connections between the ecology of the daytime and the nighttime remain largely unanswered; and (iv) that the nighttime environment is coming under severe anthropogenic pressure. In this article, I seek to reestablish nighttime ecology as a synthetic program of research, highlighting key focal topics and questions and providing an overview of the current state of understanding and developments.
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13
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Assessment of Multi-Source Evapotranspiration Products over China Using Eddy Covariance Observations. REMOTE SENSING 2018. [DOI: 10.3390/rs10111692] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
As an essential variable in linking water, carbon, and energy cycles, evapotranspiration (ET) is difficult to measure. Remote sensing, reanalysis, and land surface model-based ET products offer comprehensive alternatives at different spatio-temporal intervals, but their performance varies. In this study, we selected four popular ET global products: The Global Land Evaporation Amsterdam Model version 3.0a (GLEAM3.0a), the Modern Era Retrospective-Analysis for Research and Applications-Land (MERRA-Land) project, the Global Land Data Assimilation System version 2.0 with the Noah model (GLDAS2.0-Noah) and the EartH2Observe ensemble (EartH2Observe-En). Then, we comprehensively evaluated the performance of these products over China using a stratification method, six validation criteria, and high-quality eddy covariance (EC) measurements at 12 sites. The aim of this research was to provide important quantitative information to improve and apply the ET models and to inform choices about the appropriate ET product for specific applications. Results showed that, within one stratification, the performance of each ET product based on a certain criterion differed among classifications of this stratification. Furthermore, the optimal ET (OET) among these products was identified by comparing the magnitudes of each criterion. Results suggested that, given a criterion (a stratification classification), the OETs varied among stratification classifications (the selected six criteria). In short, no product consistently performed best, according to the selected validation criterion. Thus, multi-source ET datasets should be employed in future studies to enhance confidence in ET-related conclusions.
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14
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Erratum. Funct Ecol 2018. [DOI: 10.1111/1365-2435.13186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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