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Yin H, Perera-Castro AV, Randall KL, Turnbull JD, Waterman MJ, Dunn J, Robinson SA. Basking in the sun: how mosses photosynthesise and survive in Antarctica. PHOTOSYNTHESIS RESEARCH 2023; 158:151-169. [PMID: 37515652 PMCID: PMC10684656 DOI: 10.1007/s11120-023-01040-y] [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: 02/15/2023] [Accepted: 07/10/2023] [Indexed: 07/31/2023]
Abstract
The Antarctic environment is extremely cold, windy and dry. Ozone depletion has resulted in increasing ultraviolet-B radiation, and increasing greenhouse gases and decreasing stratospheric ozone have altered Antarctica's climate. How do mosses thrive photosynthetically in this harsh environment? Antarctic mosses take advantage of microclimates where the combination of protection from wind, sufficient melt water, nutrients from seabirds and optimal sunlight provides both photosynthetic energy and sufficient warmth for efficient metabolism. The amount of sunlight presents a challenge: more light creates warmer canopies which are optimal for photosynthetic enzymes but can contain excess light energy that could damage the photochemical apparatus. Antarctic mosses thus exhibit strong photoprotective potential in the form of xanthophyll cycle pigments. Conversion to zeaxanthin is high when conditions are most extreme, especially when water content is low. Antarctic mosses also produce UV screening compounds which are maintained in cell walls in some species and appear to protect from DNA damage under elevated UV-B radiation. These plants thus survive in one of the harshest places on Earth by taking advantage of the best real estate to optimise their metabolism. But survival is precarious and it remains to be seen if these strategies will still work as the Antarctic climate changes.
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Affiliation(s)
- Hao Yin
- Securing Antarctica's Environmental Future, University of Wollongong, Wollongong, NSW, 2522, Australia
- Centre for Sustainable Ecosystem Solutions, School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, NSW, 2522, Australia
| | | | - Krystal L Randall
- Securing Antarctica's Environmental Future, University of Wollongong, Wollongong, NSW, 2522, Australia
- Centre for Sustainable Ecosystem Solutions, School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Johanna D Turnbull
- Securing Antarctica's Environmental Future, University of Wollongong, Wollongong, NSW, 2522, Australia
- Centre for Sustainable Ecosystem Solutions, School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Melinda J Waterman
- Securing Antarctica's Environmental Future, University of Wollongong, Wollongong, NSW, 2522, Australia
- Centre for Sustainable Ecosystem Solutions, School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Jodie Dunn
- Securing Antarctica's Environmental Future, University of Wollongong, Wollongong, NSW, 2522, Australia
- Centre for Sustainable Ecosystem Solutions, School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Sharon A Robinson
- Securing Antarctica's Environmental Future, University of Wollongong, Wollongong, NSW, 2522, Australia.
- Centre for Sustainable Ecosystem Solutions, School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, NSW, 2522, Australia.
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2
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Klarenberg IJ, Keuschnig C, Salazar A, Benning LG, Vilhelmsson O. Moss and underlying soil bacterial community structures are linked to moss functional traits. Ecosphere 2023. [DOI: 10.1002/ecs2.4447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023] Open
Affiliation(s)
- Ingeborg J. Klarenberg
- Natural Resource Sciences University of Akureyri Akureyri Iceland
- Faculty of Life and Environmental Sciences University of Iceland Reykjavík Iceland
- Department of Ecological Science Vrije Universiteit Amsterdam Amsterdam Netherlands
| | - Christoph Keuschnig
- Environmental Microbial Genomics Laboratoire Ampère, CNRS, École Centrale de Lyon Écully France
- German Research Centre for Geosciences (GFZ) Interface Geochemistry Potsdam Germany
| | - Alejandro Salazar
- Faculty of Environmental and Forest Sciences Agricultural University of Iceland Reykjavík Iceland
| | - Liane G. Benning
- German Research Centre for Geosciences (GFZ) Interface Geochemistry Potsdam Germany
- Department of Earth Sciences Free University of Berlin Berlin Germany
| | - Oddur Vilhelmsson
- Natural Resource Sciences University of Akureyri Akureyri Iceland
- BioMedical Center University of Iceland Reykjavík Iceland
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3
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Strugnell JM, McGregor HV, Wilson NG, Meredith KT, Chown SL, Lau SCY, Robinson SA, Saunders KM. Emerging biological archives can reveal ecological and climatic change in Antarctica. GLOBAL CHANGE BIOLOGY 2022; 28:6483-6508. [PMID: 35900301 PMCID: PMC9826052 DOI: 10.1111/gcb.16356] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 06/27/2022] [Indexed: 06/15/2023]
Abstract
Anthropogenic climate change is causing observable changes in Antarctica and the Southern Ocean including increased air and ocean temperatures, glacial melt leading to sea-level rise and a reduction in salinity, and changes to freshwater water availability on land. These changes impact local Antarctic ecosystems and the Earth's climate system. The Antarctic has experienced significant past environmental change, including cycles of glaciation over the Quaternary Period (the past ~2.6 million years). Understanding Antarctica's paleoecosystems, and the corresponding paleoenvironments and climates that have shaped them, provides insight into present day ecosystem change, and importantly, helps constrain model projections of future change. Biological archives such as extant moss beds and peat profiles, biological proxies in lake and marine sediments, vertebrate animal colonies, and extant terrestrial and benthic marine invertebrates, complement other Antarctic paleoclimate archives by recording the nature and rate of past ecological change, the paleoenvironmental drivers of that change, and constrain current ecosystem and climate models. These archives provide invaluable information about terrestrial ice-free areas, a key location for Antarctic biodiversity, and the continental margin which is important for understanding ice sheet dynamics. Recent significant advances in analytical techniques (e.g., genomics, biogeochemical analyses) have led to new applications and greater power in elucidating the environmental records contained within biological archives. Paleoecological and paleoclimate discoveries derived from biological archives, and integration with existing data from other paleoclimate data sources, will significantly expand our understanding of past, present, and future ecological change, alongside climate change, in a unique, globally significant region.
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Affiliation(s)
- Jan M. Strugnell
- Centre for Sustainable Tropical Fisheries and Aquaculture and College of Science and EngineeringJames Cook UniversityTownsvilleQueenslandAustralia
- Securing Antarctica's Environmental FutureJames Cook UniversityTownsvilleQueenslandAustralia
| | - Helen V. McGregor
- Securing Antarctica's Environmental Future, School of Earth, Atmospheric and Life SciencesUniversity of WollongongWollongongNew South WalesAustralia
| | - Nerida G. Wilson
- Securing Antarctica's Environmental FutureWestern Australian MuseumWestern AustraliaAustralia
- Research and CollectionsWestern Australian MuseumWestern AustraliaAustralia
- School of Biological SciencesUniversity of Western AustraliaCrawleyWestern AustraliaAustralia
| | - Karina T. Meredith
- Securing Antarctica's Environmental FutureAustralian Nuclear Science and Technology OrganisationLucas HeightsNew South WalesAustralia
| | - Steven L. Chown
- Securing Antarctica's Environmental Future, School of Biological SciencesMonash UniversityMelbourneVictoriaAustralia
| | - Sally C. Y. Lau
- Centre for Sustainable Tropical Fisheries and Aquaculture and College of Science and EngineeringJames Cook UniversityTownsvilleQueenslandAustralia
- Securing Antarctica's Environmental FutureJames Cook UniversityTownsvilleQueenslandAustralia
| | - Sharon A. Robinson
- Securing Antarctica's Environmental Future, School of Earth, Atmospheric and Life SciencesUniversity of WollongongWollongongNew South WalesAustralia
| | - Krystyna M. Saunders
- Securing Antarctica's Environmental Future, School of Earth, Atmospheric and Life SciencesUniversity of WollongongWollongongNew South WalesAustralia
- Securing Antarctica's Environmental FutureAustralian Nuclear Science and Technology OrganisationLucas HeightsNew South WalesAustralia
- Institute for Marine and Antarctic StudiesUniversity of TasmaniaHobartTasmaniaAustralia
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4
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Robinson SA. Climate change and extreme events are changing the biology of Polar Regions. GLOBAL CHANGE BIOLOGY 2022; 28:5861-5864. [PMID: 35821589 DOI: 10.1111/gcb.16309] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 06/20/2022] [Indexed: 06/15/2023]
Abstract
Polar landscapes and their unique biodiversity are threatened by climate change. Wild reindeer are cultural and ecological keystone species, traversing across the northern Eurasian Arctic throughout the year (Wild reindeer in the sub-Arctic in Kuhmo, Finland. Photo: Antti Leinonen, Snowchange Cooperative. Used with permission). In contrast, Antarctic terrestrial biodiversity is found on islands in the ice (or ocean) which support unique assemblages of plants and animals (King George Island, South Shetlands; photo Andrew Netherwood. Used with permission). This VSI examines how the changing climate threatens these diverse marine and terrestrial habitats and the biodiversity that they support.
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Affiliation(s)
- Sharon A Robinson
- Securing Antarctica's Environmental Future, School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, New South Wales, Australia
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Snyder KA, Robinson SA, Schmidt S, Hultine KR. Stable isotope approaches and opportunities for improving plant conservation. CONSERVATION PHYSIOLOGY 2022; 10:coac056. [PMID: 35966756 PMCID: PMC9367551 DOI: 10.1093/conphys/coac056] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 04/15/2021] [Accepted: 08/01/2022] [Indexed: 06/01/2023]
Abstract
Successful conservation of threatened species and ecosystems in a rapidly changing world requires scientifically sound decision-making tools that are readily accessible to conservation practitioners. Physiological applications that examine how plants and animals interact with their environment are now widely used when planning, implementing and monitoring conservation. Among these tools, stable-isotope physiology is a potentially powerful, yet under-utilized cornerstone of current and future conservation efforts of threatened and endangered plants. We review the underlying concepts and theory of stable-isotope physiology and describe how stable-isotope applications can support plant conservation. We focus on stable isotopes of carbon, hydrogen, oxygen and nitrogen to address plant ecophysiological responses to changing environmental conditions across temporal scales from hours to centuries. We review examples from a broad range of plant taxa, life forms and habitats and provide specific examples where stable-isotope analysis can directly improve conservation, in part by helping identify resilient, locally adapted genotypes or populations. Our review aims to provide a guide for practitioners to easily access and evaluate the information that can be derived from stable-isotope signatures, their limitations and how stable isotopes can improve conservation efforts.
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Affiliation(s)
- Keirith A Snyder
- Corresponding author: USDA Agricultural Research Service, Great Basin Rangelands Research Unit, Reno,
920 Valley Road, NV 89512, USA.
| | - Sharon A Robinson
- School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, New South Wales 2522, Australia
- Securing Antarctica’s Environmental Future, University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - Susanne Schmidt
- School of Agriculture and Food Sciences, The University of Queensland, Building 62, Brisbane Queensland 4075, Australia
| | - Kevin R Hultine
- Department of Research, Conservation and Collections, Desert Botanical Garden, 1201 Galvin Parkway, Phoenix, AZ 85008, USA
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6
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Carbon dioxide isotopic compositions during tundra ecosystem respiration and photosynthesis in relation to environmental variables in maritime Antarctica. Polar Biol 2021. [DOI: 10.1007/s00300-021-02829-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Perera-Castro AV, Waterman MJ, Turnbull JD, Ashcroft MB, McKinley E, Watling JR, Bramley-Alves J, Casanova-Katny A, Zuniga G, Flexas J, Robinson SA. It Is Hot in the Sun: Antarctic Mosses Have High Temperature Optima for Photosynthesis Despite Cold Climate. FRONTIERS IN PLANT SCIENCE 2020; 11:1178. [PMID: 32922412 PMCID: PMC7457050 DOI: 10.3389/fpls.2020.01178] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 07/21/2020] [Indexed: 05/05/2023]
Abstract
The terrestrial flora of Antarctica's frozen continent is restricted to sparse ice-free areas and dominated by lichens and bryophytes. These plants frequently battle sub-zero temperatures, extreme winds and reduced water availability; all influencing their ability to survive and grow. Antarctic mosses, however, can have canopy temperatures well above air temperature. At midday, canopy temperatures can exceed 15°C, depending on moss turf water content. In this study, the optimum temperature of photosynthesis was determined for six Antarctic moss species: Bryum pseudotriquetrum, Ceratodon purpureus, Chorisodontium aciphyllum, Polytrichastrum alpinum, Sanionia uncinata, and Schistidium antarctici collected from King George Island (maritime Antarctica) and/or the Windmill Islands, East Antarctica. Both chlorophyll fluorescence and gas exchange showed maximum values of electron transport rate occurred at canopy temperatures higher than 20°C. The optimum temperature for both net assimilation of CO2 and photoprotective heat dissipation of three East Antarctic species was 20-30°C and at temperatures below 10°C, mesophyll conductance did not significantly differ from 0. Maximum mitochondrial respiration rates occurred at temperatures higher than 35°C and were lower by around 80% at 5°C. Despite the extreme cold conditions that Antarctic mosses face over winter, the photosynthetic apparatus appears optimised to warm temperatures. Our estimation of the total carbon balance suggests that survival in this cold environment may rely on a capacity to maximize photosynthesis for brief periods during summer and minimize respiratory carbon losses in cold conditions.
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Affiliation(s)
- Alicia V. Perera-Castro
- Department of Biology, Universitat de les Illes Balears, INAGEA, Palma de Mallorca, Spain
- Centre for Sustainable Ecosystem Solutions, School of Earth, Atmosphere and Life Sciences, University of Wollongong, Wollongong, NSW, Australia
| | - Melinda J. Waterman
- Centre for Sustainable Ecosystem Solutions, School of Earth, Atmosphere and Life Sciences, University of Wollongong, Wollongong, NSW, Australia
| | - Johanna D. Turnbull
- Centre for Sustainable Ecosystem Solutions, School of Earth, Atmosphere and Life Sciences, University of Wollongong, Wollongong, NSW, Australia
| | - Michael B. Ashcroft
- Centre for Sustainable Ecosystem Solutions, School of Earth, Atmosphere and Life Sciences, University of Wollongong, Wollongong, NSW, Australia
| | - Ella McKinley
- School of Biological Sciences, The University of Adelaide, Adelaide, SA, Australia
| | - Jennifer R. Watling
- School of Biological Sciences, The University of Adelaide, Adelaide, SA, Australia
- Manchester Metropolitan University, Manchester, United Kingdom
| | - Jessica Bramley-Alves
- Centre for Sustainable Ecosystem Solutions, School of Earth, Atmosphere and Life Sciences, University of Wollongong, Wollongong, NSW, Australia
| | - Angelica Casanova-Katny
- Laboratorio de Ecofisiología Vegetal y Cambio Climático y Núcleo de Estudios Ambientales (NEA), Facultad de Recursos Naturales, Universidad Católica de Temuco, Temuco, Chile
| | - Gustavo Zuniga
- Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - Jaume Flexas
- Department of Biology, Universitat de les Illes Balears, INAGEA, Palma de Mallorca, Spain
| | - Sharon A. Robinson
- Centre for Sustainable Ecosystem Solutions, School of Earth, Atmosphere and Life Sciences, University of Wollongong, Wollongong, NSW, Australia
- Global Challenges Program, University of Wollongong, Wollongong, NSW, Australia
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8
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Dong YP, Liu XY, Sun XC, Song W, Zheng XD, Li R, Liu CQ. Inter-species and intra-annual variations of moss nitrogen utilization: Implications for nitrogen deposition assessment. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2017; 230:506-515. [PMID: 28692942 DOI: 10.1016/j.envpol.2017.06.058] [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: 02/28/2017] [Revised: 06/16/2017] [Accepted: 06/17/2017] [Indexed: 06/07/2023]
Abstract
Moss nitrogen (N) concentrations and natural 15N abundance (δ15N values) have been widely employed to evaluate annual levels and major sources of atmospheric N deposition. However, different moss species and one-off sampling were often used among extant studies, it remains unclear whether moss N parameters differ with species and different samplings, which prevented more accurate assessment of N deposition via moss survey. Here concentrations, isotopic ratios of bulk carbon (C) and bulk N in natural epilithic mosses (Bryum argenteum, Eurohypnum leptothallum, Haplocladium microphyllum and Hypnum plumaeforme) were measured monthly from August 2006 to August 2007 at Guiyang, SW China. The H. plumaeforme had significantly (P < 0.05) lower bulk N concentrations and higher δ13C values than other species. Moss N concentrations were significantly (P < 0.05) lower in warmer months than in cooler months, while moss δ13C values exhibited an opposite pattern. The variance component analyses showed that different species contributed more variations of moss N concentrations and δ13C values than different samplings. Differently, δ15N values did not differ significantly between moss species, and its variance mainly reflected variations of assimilated N sources, with ammonium as the dominant contributor. These results unambiguously reveal the influence of inter-species and intra-annual variations of moss N utilization on N deposition assessment.
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Affiliation(s)
- Yu-Ping Dong
- Institute of Surface-Earth System Science, Tianjin University, Tianjin, 300072, China
| | - Xue-Yan Liu
- Institute of Surface-Earth System Science, Tianjin University, Tianjin, 300072, China; State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550002, China.
| | - Xin-Chao Sun
- Institute of Surface-Earth System Science, Tianjin University, Tianjin, 300072, China.
| | - Wei Song
- Institute of Surface-Earth System Science, Tianjin University, Tianjin, 300072, China
| | - Xu-Dong Zheng
- Institute of Surface-Earth System Science, Tianjin University, Tianjin, 300072, China
| | - Rui Li
- Institute of Surface-Earth System Science, Tianjin University, Tianjin, 300072, China
| | - Cong-Qiang Liu
- Institute of Surface-Earth System Science, Tianjin University, Tianjin, 300072, China; State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550002, China
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10
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Malenovský Z, Lucieer A, King DH, Turnbull JD, Robinson SA. Unmanned aircraft system advances health mapping of fragile polar vegetation. Methods Ecol Evol 2017. [DOI: 10.1111/2041-210x.12833] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Zbyněk Malenovský
- Surveying and Spatial Sciences Group School of Land and Food University of Tasmania Hobart Tas. Australia
- Centre for Sustainable Ecosystem Solutions School of Biological Sciences University of Wollongong Wollongong NSW Australia
- Biospheric Sciences Laboratory USRA/GESTAR NASA Goddard Space Flight Center Greenbelt MD USA
| | - Arko Lucieer
- Surveying and Spatial Sciences Group School of Land and Food University of Tasmania Hobart Tas. Australia
| | - Diana H. King
- Centre for Sustainable Ecosystem Solutions School of Biological Sciences University of Wollongong Wollongong NSW Australia
| | - Johanna D. Turnbull
- Centre for Sustainable Ecosystem Solutions School of Biological Sciences University of Wollongong Wollongong NSW Australia
| | - Sharon A. Robinson
- Centre for Sustainable Ecosystem Solutions School of Biological Sciences University of Wollongong Wollongong NSW Australia
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Amesbury MJ, Roland TP, Royles J, Hodgson DA, Convey P, Griffiths H, Charman DJ. Widespread Biological Response to Rapid Warming on the Antarctic Peninsula. Curr Biol 2017; 27:1616-1622.e2. [DOI: 10.1016/j.cub.2017.04.034] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Revised: 02/15/2017] [Accepted: 04/18/2017] [Indexed: 11/29/2022]
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12
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Ashcroft MB, Casanova-Katny A, Mengersen K, Rosenstiel TN, Turnbull JD, Wasley J, Waterman MJ, Zúñiga GE, Robinson SA. Bayesian methods for comparing species physiological and ecological response curves. ECOL INFORM 2016. [DOI: 10.1016/j.ecoinf.2016.03.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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13
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Royles J, Amesbury MJ, Roland TP, Jones GD, Convey P, Griffiths H, Hodgson DA, Charman DJ. Moss stable isotopes (carbon-13, oxygen-18) and testate amoebae reflect environmental inputs and microclimate along a latitudinal gradient on the Antarctic Peninsula. Oecologia 2016; 181:931-45. [PMID: 27003701 PMCID: PMC4912596 DOI: 10.1007/s00442-016-3608-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 03/08/2016] [Indexed: 11/27/2022]
Abstract
The stable isotope compositions of moss tissue water (δ(2)H and δ(18)O) and cellulose (δ(13)C and δ(18)O), and testate amoebae populations were sampled from 61 contemporary surface samples along a 600-km latitudinal gradient of the Antarctic Peninsula (AP) to provide a spatial record of environmental change. The isotopic composition of moss tissue water represented an annually integrated precipitation signal with the expected isotopic depletion with increasing latitude. There was a weak, but significant, relationship between cellulose δ(18)O and latitude, with predicted source water inputs isotopically enriched compared to measured precipitation. Cellulose δ(13)C values were dependent on moss species and water content, and may reflect site exposure to strong winds. Testate amoebae assemblages were characterised by low concentrations and taxonomic diversity, with Corythion dubium and Microcorycia radiata types the most cosmopolitan taxa. The similarity between the intra- and inter-site ranges measured in all proxies suggests that microclimate and micro-topographical conditions around the moss surface were important determinants of proxy values. Isotope and testate amoebae analyses have proven value as palaeoclimatic, temporal proxies of climate change, whereas this study demonstrates that variations in isotopic and amoeboid proxies between microsites can be beyond the bounds of the current spatial variability in AP climate.
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Affiliation(s)
- Jessica Royles
- British Antarctic Survey, High Cross, Madingley Road, Cambridge, CB3 0ET, UK.
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EA, UK.
| | - Matthew J Amesbury
- Geography, College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4RJ, UK
| | - Thomas P Roland
- Geography, College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4RJ, UK
| | - Glyn D Jones
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EA, UK
| | - Peter Convey
- British Antarctic Survey, High Cross, Madingley Road, Cambridge, CB3 0ET, UK
| | - Howard Griffiths
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EA, UK
| | - Dominic A Hodgson
- British Antarctic Survey, High Cross, Madingley Road, Cambridge, CB3 0ET, UK
| | - Dan J Charman
- Geography, College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4RJ, UK
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14
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Malenovský Z, Turnbull JD, Lucieer A, Robinson SA. Antarctic moss stress assessment based on chlorophyll content and leaf density retrieved from imaging spectroscopy data. THE NEW PHYTOLOGIST 2015; 208:608-24. [PMID: 26083501 DOI: 10.1111/nph.13524] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 05/17/2015] [Indexed: 05/04/2023]
Abstract
The health of several East Antarctic moss-beds is declining as liquid water availability is reduced due to recent environmental changes. Consequently, a noninvasive and spatially explicit method is needed to assess the vigour of mosses spread throughout rocky Antarctic landscapes. Here, we explore the possibility of using near-distance imaging spectroscopy for spatial assessment of moss-bed health. Turf chlorophyll a and b, water content and leaf density were selected as quantitative stress indicators. Reflectance of three dominant Antarctic mosses Bryum pseudotriquetrum, Ceratodon purpureus and Schistidium antarctici was measured during a drought-stress and recovery laboratory experiment and also with an imaging spectrometer outdoors on water-deficient (stressed) and well-watered (unstressed) moss test sites. The stress-indicating moss traits were derived from visible and near infrared turf reflectance using a nonlinear support vector regression. Laboratory estimates of chlorophyll content and leaf density were achieved with the lowest systematic/unsystematic root mean square errors of 38.0/235.2 nmol g(-1) DW and 0.8/1.6 leaves mm(-1) , respectively. Subsequent combination of these indicators retrieved from field hyperspectral images produced small-scale maps indicating relative moss vigour. Once applied and validated on remotely sensed airborne spectral images, this methodology could provide quantitative maps suitable for long-term monitoring of Antarctic moss-bed health.
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Affiliation(s)
- Zbyněk Malenovský
- Centre for Sustainable Ecosystem Solutions, School of Biological Sciences, University of Wollongong, Northfields Avenue, Wollongong, NSW, 2522, Australia
- Surveying and Spatial Sciences Group, School of Land and Food, University of Tasmania, Private Bag 76, Hobart, TAS, 7001, Australia
| | - Johanna D Turnbull
- Centre for Sustainable Ecosystem Solutions, School of Biological Sciences, University of Wollongong, Northfields Avenue, Wollongong, NSW, 2522, Australia
| | - Arko Lucieer
- Surveying and Spatial Sciences Group, School of Land and Food, University of Tasmania, Private Bag 76, Hobart, TAS, 7001, Australia
| | - Sharon A Robinson
- Centre for Sustainable Ecosystem Solutions, School of Biological Sciences, University of Wollongong, Northfields Avenue, Wollongong, NSW, 2522, Australia
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