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Vivanco-Bercovich M, Sandoval-Gil JM, Bonet-Meliá P, Cabello-Pasini A, Muñiz-Salazar R, Montoya LR, Schubert N, Marín-Guirao L, Procaccini G, Ferreira-Arrieta A. Marine heatwaves recurrence aggravates thermal stress in the surfgrass Phyllospadix scouleri. MARINE POLLUTION BULLETIN 2024; 199:115943. [PMID: 38176159 DOI: 10.1016/j.marpolbul.2023.115943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Revised: 12/12/2023] [Accepted: 12/14/2023] [Indexed: 01/06/2024]
Abstract
The surfgrass Phyllospadix scouleri grows in highly productive meadows along the Pacific coast of North America. This region has experienced increasingly severe marine heatwaves (MHWs) in recent years. Our study evaluated the impact of consecutive MHWs, simulated in mesocosms, on essential ecophysiological features of P. scouleri. Overall, our findings show that the plants' overall physiological status has been progressively declining. Interestingly, the indicators of physiological stress in photosynthesis only showed up once the initial heat exposure stopped (i.e., during the recovery period). The warming caused increased oxidative damage and a decrease in nitrate uptake rates. However, the levels of non-structural carbohydrates and relative growth rates were not affected. Our findings emphasize the significance of incorporating recovery periods in this type of study as they expose delayed stress responses. Furthermore, experiencing consecutive intense MHWs can harm surfgrasses over time, compromising the health of their meadows and the services they offer to the ecosystem.
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Affiliation(s)
- Manuel Vivanco-Bercovich
- Universidad Autónoma de Baja California (UABC), Instituto de Investigaciones Oceanológicas (IIO), Marine Botany Research Group, Ensenada, Baja California, Mexico
| | - Jose Miguel Sandoval-Gil
- Universidad Autónoma de Baja California (UABC), Instituto de Investigaciones Oceanológicas (IIO), Marine Botany Research Group, Ensenada, Baja California, Mexico.
| | - Paula Bonet-Meliá
- Universidad Autónoma de Baja California (UABC), Instituto de Investigaciones Oceanológicas (IIO), Marine Botany Research Group, Ensenada, Baja California, Mexico
| | - Alejandro Cabello-Pasini
- Universidad Autónoma de Baja California (UABC), Instituto de Investigaciones Oceanológicas (IIO), Marine Botany Research Group, Ensenada, Baja California, Mexico
| | - Raquel Muñiz-Salazar
- Universidad Autónoma de Baja California (UABC), Instituto de Investigaciones Oceanológicas (IIO), Marine Botany Research Group, Ensenada, Baja California, Mexico; Universidad Autónoma de Baja California (UABC), Escuela de Ciencias de la Salud, Ensenada, Baja California, Mexico
| | - Leonardo Ruiz Montoya
- Universidad Autónoma de Baja California (UABC), Instituto de Investigaciones Oceanológicas (IIO), Marine Botany Research Group, Ensenada, Baja California, Mexico
| | - Nadine Schubert
- CCMAR - Center of Marine Sciences, University of Algarve, Faro, Portugal
| | - Lázaro Marín-Guirao
- Instituto Español de Oceanografía (IEO), Centro Oceanográfico de Murcia, Seagrass Ecology Group, C/Varadero s/n, 30740 San Pedro del Pinatar, Murcia, Spain
| | - Gabriele Procaccini
- Stazione Zoologica Anton Dohrn, Department of Integrative Marine Ecology, Villa Comunale, Naples, Italy
| | - Alejandra Ferreira-Arrieta
- Universidad Autónoma de Baja California (UABC), Instituto de Investigaciones Oceanológicas (IIO), Marine Botany Research Group, Ensenada, Baja California, Mexico
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Ismael M, Charras Q, Leschevin M, Herfurth D, Roulard R, Quéro A, Rusterucci C, Domon JM, Jungas C, Vermerris W, Rayon C. Seasonal Variation in Cell Wall Composition and Carbohydrate Metabolism in the Seagrass Posidonia oceanica Growing at Different Depths. PLANTS (BASEL, SWITZERLAND) 2023; 12:3155. [PMID: 37687400 PMCID: PMC10490095 DOI: 10.3390/plants12173155] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 08/26/2023] [Accepted: 08/28/2023] [Indexed: 09/10/2023]
Abstract
Posidonia oceanica is a common seagrass in the Mediterranean Sea that is able to sequester large amounts of carbon. The carbon assimilated during photosynthesis can be partitioned into non-structural sugars and cell-wall polymers. In this study, we investigated the distribution of carbon in starch, soluble carbohydrates and cell-wall polymers in leaves and rhizomes of P. oceanica. Analyses were performed during summer and winter in meadows located south of the Frioul archipelago near Marseille, France. The leaves and rhizomes were isolated from plants collected in shallow (2 m) and deep water (26 m). Our results showed that P. oceanica stores more carbon as starch, sucrose and cellulose in summer and that this is more pronounced in rhizomes from deep-water plants. In winter, the reduction in photoassimilates was correlated with a lower cellulose content, compensated with a greater lignin content, except in rhizomes from deep-water plants. The syringyl-to-guaiacyl (S/G) ratio in the lignin was higher in leaves than in rhizomes and decreased in rhizomes in winter, indicating a change in the distribution or structure of the lignin. These combined data show that deep-water plants store more carbon during summer, while in winter the shallow- and deep-water plants displayed a different cell wall composition reflecting their environment.
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Affiliation(s)
- Marwa Ismael
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, BIOlogie des Plantes et Innovation (BIOPI), Université de Picardie Jules Verne, 80039 Amiens, France; (M.I.); (M.L.); (D.H.); (R.R.); (A.Q.); (C.R.); (J.-M.D.)
| | - Quentin Charras
- Aix-Marseille University, CEA, CNRS, BIAM, LGBP Team, 13009 Marseille, France; (Q.C.); (C.J.)
| | - Maïté Leschevin
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, BIOlogie des Plantes et Innovation (BIOPI), Université de Picardie Jules Verne, 80039 Amiens, France; (M.I.); (M.L.); (D.H.); (R.R.); (A.Q.); (C.R.); (J.-M.D.)
- Aix-Marseille University, CEA Cadarache, Zone Cité des Énergies BIAM, Bâtiment 1900, 13108 Saint-Paul-lez-Durance, France
| | - Damien Herfurth
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, BIOlogie des Plantes et Innovation (BIOPI), Université de Picardie Jules Verne, 80039 Amiens, France; (M.I.); (M.L.); (D.H.); (R.R.); (A.Q.); (C.R.); (J.-M.D.)
| | - Romain Roulard
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, BIOlogie des Plantes et Innovation (BIOPI), Université de Picardie Jules Verne, 80039 Amiens, France; (M.I.); (M.L.); (D.H.); (R.R.); (A.Q.); (C.R.); (J.-M.D.)
| | - Anthony Quéro
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, BIOlogie des Plantes et Innovation (BIOPI), Université de Picardie Jules Verne, 80039 Amiens, France; (M.I.); (M.L.); (D.H.); (R.R.); (A.Q.); (C.R.); (J.-M.D.)
| | - Christine Rusterucci
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, BIOlogie des Plantes et Innovation (BIOPI), Université de Picardie Jules Verne, 80039 Amiens, France; (M.I.); (M.L.); (D.H.); (R.R.); (A.Q.); (C.R.); (J.-M.D.)
| | - Jean-Marc Domon
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, BIOlogie des Plantes et Innovation (BIOPI), Université de Picardie Jules Verne, 80039 Amiens, France; (M.I.); (M.L.); (D.H.); (R.R.); (A.Q.); (C.R.); (J.-M.D.)
| | - Colette Jungas
- Aix-Marseille University, CEA, CNRS, BIAM, LGBP Team, 13009 Marseille, France; (Q.C.); (C.J.)
| | - Wilfred Vermerris
- Department of Microbiology & Cell Science and UF Genetics Institute, University of Florida, Gainesville, FL 32610, USA;
| | - Catherine Rayon
- UMR-INRAE 1158 Transfrontalière BioEcoAgro, BIOlogie des Plantes et Innovation (BIOPI), Université de Picardie Jules Verne, 80039 Amiens, France; (M.I.); (M.L.); (D.H.); (R.R.); (A.Q.); (C.R.); (J.-M.D.)
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Andskog MA, Layman C, Allgeier JE. Seagrass production around artificial reefs is resistant to human stressors. Proc Biol Sci 2023; 290:20230803. [PMID: 37491960 PMCID: PMC10369039 DOI: 10.1098/rspb.2023.0803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 06/16/2023] [Indexed: 07/27/2023] Open
Abstract
Primary production underpins most ecosystem services, including carbon sequestration and fisheries. Artificial reefs (ARs) are widely used for fisheries management. Research has shown that a mechanism by which ARs in seagrass beds can support fisheries and carbon sequestration is through increasing primary production via fertilization from aggregating fish excretion. Seagrass beds are heavily affected by anthropogenic nutrient input and fishing that reduces nutrient input by consumers. The effect of these stressors is difficult to predict because impacts of simultaneous stressors are typically non-additive. We used a long-term experiment to identify the mechanisms by which simultaneous impacts of sewage enrichment and fishing alter seagrass production around ARs across non-orthogonal gradients in human-dominated and relatively unimpacted regions in Haiti and The Bahamas. Merging trait-based measures of seagrass and seagrass ecosystem processes, we found that ARs consistently enhanced per capita seagrass production and maintained ecosystem-scale production despite drastic shifts in controls on production from human stressors. Importantly, we also show that coupled human stressors on seagrass production around ARs were additive, contrasting expectations. These findings are encouraging for conservation because they indicate that seagrass ecosystems are highly resistant to coupled human stressors and that ARs promote ecosystem services even in human-dominated ecosystems.
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Affiliation(s)
- Mona A. Andskog
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109, USA
- Centre for Coastal Biogeochemistry, Southern Cross University, Lismore, NSW 2480, Australia
| | - Craig Layman
- Center for Energy, Environment, and Sustainability, Department of Biology, Wake Forest University, Winston-Salem, NC 27109, USA
| | - Jacob E. Allgeier
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109, USA
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Minguito-Frutos M, Adams MP, Alcoverro T, Vilas MP, Alonso D, Mayol E, Bernardeu-Esteller J, Marín-Guirao L, Ruiz JM, Boada J. Quantifying the role of photoacclimation and self-facilitation for seagrass resilience to light deprivation. FRONTIERS IN PLANT SCIENCE 2023; 14:1186538. [PMID: 37546272 PMCID: PMC10401047 DOI: 10.3389/fpls.2023.1186538] [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: 03/14/2023] [Accepted: 06/28/2023] [Indexed: 08/08/2023]
Abstract
Introduction Light gradients are ubiquitous in marine systems as light reduces exponentially with depth. Seagrasses have a set of mechanisms that help them to cope with light stress gradients. Physiological photoacclimation and clonal integration help to maximize light capture and minimize carbon losses. These mechanisms can shape plants minimum light requirements (MLR), which establish critical thresholds for seagrass survival and help us predict ecosystem responses to the alarming reduction in light availability. Methods Using the seagrass Cymodocea nodosa as a case study, we compare the MLR under different carbon model scenarios, which include photoacclimation and/or self-facilitation (based on clonal integration) and that where parameterized with values from field experiments. Results Physiological photoacclimation conferred plants with increased tolerance to reducing light, approximately halving their MLR from 5-6% surface irradiance (SI) to ≈ 3% SI. In oligotrophic waters, this change in MLR could translate to an increase of several meters in their depth colonization limit. In addition, we show that reduced mortality rates derived from self-facilitation mechanisms (promoted by high biomass) induce bistability of seagrass meadows along the light stress gradient, leading to abrupt shifts and hysteretic behaviors at their deep limit. Discussion The results from our models point to (i) the critical role of physiological photoacclimation in conferring greater resistance and ability to recover (i.e., resilience), to seagrasses facing light deprivation and (ii) the importance of self-facilitating reinforcing mechanisms in driving the resilience and recovery of seagrass systems exposed to severe light reduction events.
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Affiliation(s)
- Mario Minguito-Frutos
- Centre d’Estudis Avançats de Blanes (CEAB-CSIC), Carrer d’Accés a la cala Sant Francesc, Girona, Spain
| | - Matthew P. Adams
- School of Mathematical Sciences, Queensland University of Technology, Brisbane, QLD, Australia
- Centre for Data Science, Queensland University of Technology, Brisbane, QLD, Australia
- School of Chemical Engineering, The University of Queensland, St. Lucia, QLD, Australia
| | - Teresa Alcoverro
- Centre d’Estudis Avançats de Blanes (CEAB-CSIC), Carrer d’Accés a la cala Sant Francesc, Girona, Spain
| | - María P. Vilas
- Department of Environment and Science, Queensland Government, Brisbane, QLD, Australia
| | - David Alonso
- Centre d’Estudis Avançats de Blanes (CEAB-CSIC), Carrer d’Accés a la cala Sant Francesc, Girona, Spain
| | - Elvira Mayol
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
- Department of Global Change Research, IMEDEA (Mediterranean Institute for Advanced Studies) (UIB-CSIC), Esporles, Spain
| | - Jaime Bernardeu-Esteller
- Seagrass Ecology Group, Oceanographic Center of Murcia, Spanish Institute of Oceanography (IEO-CSIC), Murcia, Spain
| | - Lázaro Marín-Guirao
- Seagrass Ecology Group, Oceanographic Center of Murcia, Spanish Institute of Oceanography (IEO-CSIC), Murcia, Spain
| | - Juan M. Ruiz
- Seagrass Ecology Group, Oceanographic Center of Murcia, Spanish Institute of Oceanography (IEO-CSIC), Murcia, Spain
| | - Jordi Boada
- Centre d’Estudis Avançats de Blanes (CEAB-CSIC), Carrer d’Accés a la cala Sant Francesc, Girona, Spain
- Laboratoire d’Océanographie de Villefranche-sur-Mer, CNRS, Sorbonne Université, Villefranche sur mer, France
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Sandoval-Gil JM, Ruiz JM, Marín-Guirao L. Advances in understanding multilevel responses of seagrasses to hypersalinity. MARINE ENVIRONMENTAL RESEARCH 2023; 183:105809. [PMID: 36435174 DOI: 10.1016/j.marenvres.2022.105809] [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: 08/22/2022] [Revised: 11/07/2022] [Accepted: 11/08/2022] [Indexed: 06/16/2023]
Abstract
Human- and nature-induced hypersaline conditions in coastal systems can lead to profound alterations of the structure and vitality of seagrass meadows and their socio-ecological benefits. In the last two decades, recent research efforts (>50 publications) have contributed significantly to unravel the physiological basis underlying the seagrass-hypersalinity interactions, although most (∼70%) are limited to few species (e.g. Posidonia oceanica, Zostera marina, Thalassia testudinum, Cymodocea nodosa). Variables related to photosynthesis and carbon metabolism are among the most prevalent in the literature, although other key metabolic processes such as plant water relations and responses at molecular (i.e. gene expression) and ultrastructure level are attracting attention. This review emphasises all these latest insights, offering an integrative perspective on the interplay among biological responses across different functional levels (from molecular to clonal structure), and their interaction with biotic/abiotic factors including those related to climate change. Other issues such as the role of salinity in driving the evolutionary trajectory of seagrasses, their acclimation mechanisms to withstand salinity increases or even the adaptive properties of populations that have historically lived under hypersaline conditions are also included. The pivotal role of the costs and limits of phenotypic plasticity in the successful acclimation of marine plants to hypersalinity is also discussed. Finally, some lines of research are proposed to fill the remaining knowledge gaps.
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Affiliation(s)
- Jose Miguel Sandoval-Gil
- Universidad Autónoma de Baja California (UABC), Instituto de Investigaciones Oceanológicas (IIO), Marine Botany Research Group, Ensenada, Baja California, 22860, Mexico
| | - Juan M Ruiz
- Seagrass Ecology Group, Spanish Institute of Oceanography (IEO-CSIC), C/ Varadero s/n, 30740 San Pedro del Pinatar, Murcia, Spain
| | - Lázaro Marín-Guirao
- Seagrass Ecology Group, Spanish Institute of Oceanography (IEO-CSIC), C/ Varadero s/n, 30740 San Pedro del Pinatar, Murcia, Spain.
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Mayol E, Boada J, Pérez M, Sanmartí N, Minguito-Frutos M, Arthur R, Alcoverro T, Alonso D, Romero J. Understanding the depth limit of the seagrass Cymodocea nodosa as a critical transition: Field and modeling evidence. MARINE ENVIRONMENTAL RESEARCH 2022; 182:105765. [PMID: 36252284 DOI: 10.1016/j.marenvres.2022.105765] [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: 07/21/2022] [Revised: 09/30/2022] [Accepted: 09/30/2022] [Indexed: 06/16/2023]
Abstract
Changes in light and sediment conditions can sometimes trigger abrupt regime shifts in seagrass meadows resulting in dramatic and unexpected die-offs of seagrass. Light attenuates rapidly with depth, and in seagrass systems with non-linear behaviours, can serve as a sharp boundary beyond which the meadow transitions to bare sand. Determining system behaviour is therefore essential to ensuring resilience is maintained and to prevent stubborn critical ecosystem transitions caused by declines in water quality. Here we combined field and modelling studies to explore the transition from meadow to bare sand in the seagrass Cymodocea nodosa at the limit of its depth distribution in a shallow, light-limited bay. We first describe the relationship between light availability and seagrass density along a depth gradient in an extensive unfragmented meadow (Alfacs bay, NE Spain). We then develop a simple mechanistic model to characterise system behaviour. In the field, we identified sharp decline in shoot density beyond a threshold of ∼1.9 m depth, shifting from a vegetated state to bare sand. The dynamic population model we developed assumes light-dependent growth and an inverse density-dependent mortality due to facilitation between shoots (mortality rate decreases as shoot density increases). The model closely tracked our empirical observations, and both the model and the field data showed signs of bistability. This strongly suggests that the depth limit of C. nodosa is a critical transition driven by photosynthetic light requirements. While the mechanisms still need to be confirmed with experimental evidence, recognizing the non-linear behaviour of C. nodosa meadows is vital not only in improving our understanding of light effects on seagrass dynamics, but also in managing shallow-water meadows. Given the shallow threshold (<2m), light-limited systems may experience significant and recalcitrant meadow retractions with even small changes in sediment and light conditions. Understanding the processes underlying meadow resilience can inform the maintenance and restoration of meadows worldwide.
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Affiliation(s)
- Elvira Mayol
- Institut Mediterrani d'Estudis Avançats (IMEDEA-CSIC), Carrer Miquel Marqués 21, 07190, Esporles, Spain.
| | - Jordi Boada
- Laboratoire d'Océanographie de Villefranche, Sorbonne Université, Villefranche-sur-Mer, France
| | - Marta Pérez
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Facultat de Biologia, Universitat de Barcelona, Avinguda Diagonal 643, 08028, Barcelona, Spain
| | - Neus Sanmartí
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Facultat de Biologia, Universitat de Barcelona, Avinguda Diagonal 643, 08028, Barcelona, Spain
| | - Mario Minguito-Frutos
- Centre d'Estudis Avançats de Blanes (CEAB-CSIC), Carrer d'Accés a la cala Sant Francesc 14, 17300, Blanes, Spain
| | - Rohan Arthur
- Centre d'Estudis Avançats de Blanes (CEAB-CSIC), Carrer d'Accés a la cala Sant Francesc 14, 17300, Blanes, Spain; Nature Conservation Foundation, 1311 Amritha, 12th Cross, Vijayanagara 1st Stage, Mysore, 570017, India
| | - Teresa Alcoverro
- Centre d'Estudis Avançats de Blanes (CEAB-CSIC), Carrer d'Accés a la cala Sant Francesc 14, 17300, Blanes, Spain; Nature Conservation Foundation, 1311 Amritha, 12th Cross, Vijayanagara 1st Stage, Mysore, 570017, India
| | - David Alonso
- Centre d'Estudis Avançats de Blanes (CEAB-CSIC), Carrer d'Accés a la cala Sant Francesc 14, 17300, Blanes, Spain
| | - Javier Romero
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Facultat de Biologia, Universitat de Barcelona, Avinguda Diagonal 643, 08028, Barcelona, Spain
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González-Guerrero LA, Vásquez-Elizondo RM, López-Londoño T, Hernán G, Iglesias-Prieto R, Enríquez S. Validation of parameters and protocols derived from chlorophyll a fluorescence commonly utilised in marine ecophysiological studies. FUNCTIONAL PLANT BIOLOGY : FPB 2022; 49:517-532. [PMID: 34372966 DOI: 10.1071/fp21101] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 07/08/2021] [Indexed: 06/13/2023]
Abstract
This study documents the first validation of the suitability of the most common parameters and protocols used in marine ecophysiology to characterise photosynthesis by means of chlorophyll a fluorescence tools. We demonstrate that the effective yield of PSII (ΔF /F m ') is significantly underestimated when using short inductions times (≤1 min) following the rapid light curve protocol (RLC). The consequent electron transport rates (ETR) underestimations are species-specific and highly variable with irradiance and the photoacclimatory condition of the sample. Our analysis also questions the use of relative descriptors (relETR), as they not only overestimate photosynthesis, but overlook one of the fundamental components of the photosynthetic response: light absorption regulation. Absorptance determinations were fundamental to characterise the ETR response of low-pigmented seagrass leaves, and also uncovered relevant differences between two coral species and the accclimatory response of a cultured dinoflagellate to temperature. ETR and oxygen evolution determinations showed close correlations for all organisms tested with the expected slope of 4 e- per O2 molecule evolved, when correct photosynthesis inductions and light absorption determinations were applied. However, ETR curves cannot be equated to conventional photosynthetic response to irradiance (P vs E ) curves, and caution is needed when using ETR to characterise photosynthesis rates above photosynthesis saturation (E k ). This validation strongly supports the utility of fluorescence tools, underlining the need to correct two decades of propagation of erroneous concepts, protocols and parameters in marine eco-physiology. We aim also to emphasise the importance of optical descriptions for understanding photosynthesis, and for interpreting fluorescence measurements. In combination with conventional gross photosynthesis (GPS) approaches, optical characterisations open an extraordinary opportunity to determine two central parameters of photosynthesis performance: the quantum yield (φmax ) of the process and its minimum quantum requirements (1/φmax ). The combination of both approaches potentiates the possibilities of chlorophyll a fluorescence tools to characterise marine photosynthesis biodiversity.
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Affiliation(s)
| | - Román M Vásquez-Elizondo
- Laboratory of Photobiology of coral reef primary producers, Unidad Académica de Sistemas Arrecifales Puerto Morelos, Universidad Nacional Autónoma de México (UNAM), Apartado Postal 13, 77500 Cancún, Mexico; and Present address: Laboratorio de Ficología Aplicada, Departamento de Recursos del Mar, CINVESTAV, Mérida
| | | | - Gema Hernán
- Laboratory of Photobiology of coral reef primary producers, Unidad Académica de Sistemas Arrecifales Puerto Morelos, Universidad Nacional Autónoma de México (UNAM), Apartado Postal 13, 77500 Cancún, Mexico
| | | | - Susana Enríquez
- Laboratory of Photobiology of coral reef primary producers, Unidad Académica de Sistemas Arrecifales Puerto Morelos, Universidad Nacional Autónoma de México (UNAM), Apartado Postal 13, 77500 Cancún, Mexico; and Corresponding author
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8
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Marín-Guirao L, Bernardeau-Esteller J, Belando MD, García-Muñoz R, Ramos-Segura A, Alcoverro T, Minguito-Frutos M, Ruiz JM. Photo-acclimatory thresholds anticipate sudden shifts in seagrass ecosystem state under reduced light conditions. MARINE ENVIRONMENTAL RESEARCH 2022; 177:105636. [PMID: 35569182 DOI: 10.1016/j.marenvres.2022.105636] [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: 11/26/2021] [Revised: 03/24/2022] [Accepted: 04/25/2022] [Indexed: 06/15/2023]
Abstract
Seagrass ecosystems usually respond in a nonlinear fashion to increasing pressures and environmental changes. Feedback mechanisms operating at the ecosystem level and involving multiple interactions among the seagrass meadow, its associated community and the physical environment are known to play a major role in such nonlinear responses. Phenotypic plasticity may also be important for buffering these ecological thresholds (i.e., regime shifts) as many physiological processes show nonlinear responses to gradual environmental changes, conferring the appearance of resistance before the effects at the organism and population levels are visible. However, the potential involvement of plant plasticity in driving catastrophic shifts in seagrass ecosystems has not yet been assessed. In this study, we conducted a manipulative 6-month light-gradient experiment in the field to capture nonlinearities of the physiological and population responses of the seagrass Cymodocea nodosa to gradual light reduction. The aim was to explore if and how the photo-acclimatory responses of shaded plants are translated to the population level and, hence, to the ecosystem level. Results showed that the seagrass population was rather stable under increasing shading levels through the activation of multilevel photo-acclimative responses, which are initiated with light reduction and modulated in proportion to shading intensity. The activation of photo-physiological and metabolic compensatory responses allowed shaded plants to sustain nearly constant plant productivity (metabolic carbon balance) along a range of shading levels before losing linearity and starting to decline. The species then activated plant- and meadow-scale photo-acclimative responses and drew on its energy reserves (rhizome carbohydrates) to confer additional population resilience. However, when the integration of all these buffering mechanisms failed to counterbalance the effects of extreme light limitation, the population collapsed, giving place to a phase shift from vegetated to bare sediments with catastrophic ecosystem outcomes. Our findings evidence that ecological thresholds in seagrass ecosystems under light limitation can be explained by the role of species' compensatory responses in modulating population-level responses. The thresholds of these plastic responses anticipate the sudden loss of seagrass meadows with the potential to be used as early warning indicators signalling the imminent collapse of the ecosystem, which is of great value for the real-world management of seagrass ecosystems.
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Affiliation(s)
- L Marín-Guirao
- Seagrass Ecology Group, Oceanographic Center of Murcia, Spanish Institute of Oceanography (IEO-CSIC), C/Varadero, 30740, San Pedro del Pinatar, Murcia, Spain.
| | - J Bernardeau-Esteller
- Seagrass Ecology Group, Oceanographic Center of Murcia, Spanish Institute of Oceanography (IEO-CSIC), C/Varadero, 30740, San Pedro del Pinatar, Murcia, Spain
| | - M D Belando
- Seagrass Ecology Group, Oceanographic Center of Murcia, Spanish Institute of Oceanography (IEO-CSIC), C/Varadero, 30740, San Pedro del Pinatar, Murcia, Spain
| | - R García-Muñoz
- Seagrass Ecology Group, Oceanographic Center of Murcia, Spanish Institute of Oceanography (IEO-CSIC), C/Varadero, 30740, San Pedro del Pinatar, Murcia, Spain
| | - A Ramos-Segura
- Seagrass Ecology Group, Oceanographic Center of Murcia, Spanish Institute of Oceanography (IEO-CSIC), C/Varadero, 30740, San Pedro del Pinatar, Murcia, Spain
| | - T Alcoverro
- Centre d'Estudis Avançats de Blanes (CEAB-CSIC), Acces Cala Sant Francesc 14, 17300, Blanes, Spain
| | - M Minguito-Frutos
- Centre d'Estudis Avançats de Blanes (CEAB-CSIC), Acces Cala Sant Francesc 14, 17300, Blanes, Spain
| | - J M Ruiz
- Seagrass Ecology Group, Oceanographic Center of Murcia, Spanish Institute of Oceanography (IEO-CSIC), C/Varadero, 30740, San Pedro del Pinatar, Murcia, Spain
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9
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Peralta G, Godoy O, Egea LG, de Los Santos CB, Jiménez-Ramos R, Lara M, Brun FG, Hernández I, Olivé I, Vergara JJ, González-Ortiz V, Moreno-Marín F, Morris EP, Villazán B, Pérez-Lloréns JL. The morphometric acclimation to depth explains the long-term resilience of the seagrass Cymodocea nodosa in a shallow tidal lagoon. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 299:113452. [PMID: 34526276 DOI: 10.1016/j.jenvman.2021.113452] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 07/27/2021] [Accepted: 07/30/2021] [Indexed: 06/13/2023]
Abstract
Cadiz Bay is a shallow mesotidal lagoon with extensive populations of the seagrass Cymodocea nodosa at intertidal and shallow subtidal elevations. This work aims to understand the mechanisms behind the resilience of this species to gradual sea level rise by studying its acclimation capacity to depth along the shallow littoral, and therefore, to gradual variations in the light environment. To address this objective, these populations have been monitored seasonally over a 10 year period, representing the longest seasonal database available in the literature for this species. The monitoring included populations at 0.4, -0.08 and -0.5 m LAT. The results show that C. nodosa has a strong seasonality for demographic and shoot dynamic properties - with longer shoots and larger growth in summer (high temperature) than in winter (low temperature), but also some losses. Moreover, shoots have different leaf morphometry depending on depth, with small and dense shoots in the intertidal areas (0.4 m) and sparse large shoots in the subtidal ones (-0.08 and 0.5 m). These differences in morphometry and shoot dynamic properties, combined with the differences in shoot density, explain the lack of differences in meadow production balance (i.e. meadow growth - meadow losses) between the intertidal (0.4 m) and the deepest population (-0.5 m), supporting the long term resilience of Cymodocea nodosa in Cadiz Bay. This study contributes to the understanding of the mechanisms behind seagrass stability and resilience, which is particularly important towards predicting the effects of climate change on these key coastal ecosystems, and also highlights the value of continuous long-term monitoring efforts to evaluate seagrass trajectories.
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Affiliation(s)
- G Peralta
- Department of Biology, University of Cadiz, Spain.
| | - O Godoy
- Department of Biology, University of Cadiz, Spain
| | - L G Egea
- Department of Biology, University of Cadiz, Spain
| | - C B de Los Santos
- Department of Biology, University of Cadiz, Spain; Centre of Marine Sciences, University of Algarve, Portugal
| | | | - M Lara
- Department of Biology, University of Cadiz, Spain; Dpto. Ecología y Geología, University of Malaga, Spain
| | - F G Brun
- Department of Biology, University of Cadiz, Spain
| | - I Hernández
- Department of Biology, University of Cadiz, Spain
| | - I Olivé
- Department of Biology, University of Cadiz, Spain; Stazione Zoologica Anton Dohrn, Italy
| | - J J Vergara
- Department of Biology, University of Cadiz, Spain
| | | | | | - E P Morris
- Department of Biology, University of Cadiz, Spain
| | - B Villazán
- Department of Biology, University of Cadiz, Spain; TAXUS Medio Ambiente S.L., Spain
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10
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Donaher SE, Baillie CJ, Smith CS, Zhang YS, Albright A, Trackenberg SN, Wellman EH, Woodard N, Gittman RK. Bivalve facilitation mediates seagrass recovery from physical disturbance in a temperate estuary. Ecosphere 2021. [DOI: 10.1002/ecs2.3804] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Sarah E. Donaher
- Institute of Marine Sciences University of North Carolina at Chapel Hill Morehead City North Carolina 28557 USA
- Department of Environmental Engineering and Earth Sciences Clemson University Anderson South Carolina 29625 USA
| | | | - Carter S. Smith
- Duke University Marine Laboratory Beaufort North Carolina 28516 USA
| | - Y. Stacy Zhang
- Institute of Marine Sciences University of North Carolina at Chapel Hill Morehead City North Carolina 28557 USA
| | - Anna Albright
- Department of Biology East Carolina University Greenville North Carolina 27858 USA
| | - Stacy N. Trackenberg
- Department of Biology East Carolina University Greenville North Carolina 27858 USA
| | - Emory H. Wellman
- Department of Biology East Carolina University Greenville North Carolina 27858 USA
| | - Nina Woodard
- Department of Biology East Carolina University Greenville North Carolina 27858 USA
| | - Rachel K. Gittman
- Institute of Marine Sciences University of North Carolina at Chapel Hill Morehead City North Carolina 28557 USA
- Department of Biology East Carolina University Greenville North Carolina 27858 USA
- Coastal Studies Institute East Carolina University Wanchese North Carolina 27891 USA
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11
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Leiva-Dueñas C, Martínez Cortizas A, Piñeiro-Juncal N, Díaz-Almela E, Garcia-Orellana J, Mateo MA. Long-term dynamics of production in western Mediterranean seagrass meadows: Trade-offs and legacies of past disturbances. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 754:142117. [PMID: 33254936 DOI: 10.1016/j.scitotenv.2020.142117] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 08/12/2020] [Accepted: 08/30/2020] [Indexed: 06/12/2023]
Abstract
Seagrasses are marine angiosperms that can form highly productive, and valuable underwater meadows, which are currently in regression. A reliable assessment of their status and future evolution requires studies encompassing long-term temporal scales. With the aim of understanding seagrass ecosystem dynamics over the last centuries and millennia, twelve sediment cores were studied from seagrass meadows located along the Andalusian coast and at the Cabrera Island (western Mediterranean). This study is pioneer in using Fourier Transform Infrared (FTIR) spectroscopy as a tool to study environmental change in seagrass sediments. FTIR is a form of vibrational spectroscopy that provides information about the sediment chemical composition. Principal Component Analysis (PCA) was used to summarise spatio-temporal data of the FTIR vibratory peaks in combination with climate and geochemical proxy data. Several PCA signals were identified: (1) one likely related to the relative changes of the main primary producers and the sedimentary environment (carbonate or siliciclastic sediments, with aromatic or aliphatic organic matter); (2) the marine community production (polysaccharides, total organic matter content and biogenic silica); and (3) the seagrass production (aromatics, carbohydrates, phenols, proteins and lipids). A decrease of seagrass production along the mainland coast was evident since AD ~1850, which may be due to combined negative impacts of seawater warming, local anthropogenic impacts, and extreme setting conditions. The legacy of these combined stressors might have influenced the current poor state of seagrass meadows in the Alboran Sea. Our results also revealed a significant long-term trade-off between the level of seagrass production and its temporal stability (calculated as the inverse of the coefficient of variation). This study provides a reliable baseline data, helping to assess the magnitude of seagrass regression and its drivers. This paleoecological information can help design more targeted management plans and identify meadows where local management could be more efficient.
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Affiliation(s)
- Carmen Leiva-Dueñas
- Centro de Estudios Avanzados de Blanes, Consejo Superior de Investigaciones Científicas, Blanes, Spain.
| | - Antonio Martínez Cortizas
- EcoPast (GI-1553), Facultade de Bioloxia, Universidade de Santiago de Compostela, Santiago de Compostela, Spain; Centro de Estudios Avanzados de Blanes, Consejo Superior de Investigaciones Científicas, Blanes, Spain
| | - Nerea Piñeiro-Juncal
- EcoPast (GI-1553), Facultade de Bioloxia, Universidade de Santiago de Compostela, Santiago de Compostela, Spain; Centro de Estudios Avanzados de Blanes, Consejo Superior de Investigaciones Científicas, Blanes, Spain
| | - Elena Díaz-Almela
- Centro de Estudios Avanzados de Blanes, Consejo Superior de Investigaciones Científicas, Blanes, Spain
| | - Jordi Garcia-Orellana
- Institut de Ciència i Tecnologia Ambientals, Universitat Autònoma de Barcelona, Barcelona, Spain; Departament de Física, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Miguel A Mateo
- Centro de Estudios Avanzados de Blanes, Consejo Superior de Investigaciones Científicas, Blanes, Spain; School of Natural Sciences, Centre for Marine Ecosystems Research, Edith Cowan University, Joondalup, Australia
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12
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Trevizan Segovia B, Sanders-Smith R, Adamczyk EM, Forbes C, Hessing-Lewis M, O'Connor MI, Parfrey LW. Microeukaryotic Communities Associated With the Seagrass Zostera marina Are Spatially Structured. J Eukaryot Microbiol 2020; 68:e12827. [PMID: 33065761 DOI: 10.1111/jeu.12827] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 09/24/2020] [Accepted: 10/06/2020] [Indexed: 11/29/2022]
Abstract
Epibiotic microorganisms link seagrass productivity to higher trophic levels, but little is known about the processes structuring these communities, and which taxa consistently associate with seagrass. We investigated epibiotic microeukaryotes on seagrass (Zostera marina) leaves, substrates, and planktonic microeukaryotes in ten meadows in the Northeast Pacific. Seagrass epibiotic communities are distinct from planktonic and substrate communities. We found sixteen core microeukaryotes, including dinoflagellates, diatoms, and saprotrophic stramenopiles. Some likely use seagrass leaves as a substrate, others for grazing, or they may be saprotrophic organisms involved in seagrass decomposition or parasites; their relatives have been previously reported from marine sediments and in association with other hosts such as seaweeds. Core microeukaryotes were spatially structured, and none were ubiquitous across meadows. Seagrass epibiota were more spatially structured than planktonic communities, mostly due to spatial distance and changes in abiotic conditions across space. Seawater communities were relatively more similar in composition across sites and more influenced by the environmental component, but more variable over time. Core and transient taxa were both mostly structured by spatial distance and the abiotic environment, with little effect of host attributes, further indicating that those core taxa would not show a strong specific association with Z. marina.
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Affiliation(s)
- Bianca Trevizan Segovia
- Botany and Biodiversity Research Centre, University of British Columbia, Unceded xʷməθkʷəýəm (Musqueam) Territory, 3529-6270 University Blvd., Vancouver, BC, V6T 1Z4, Canada.,Hakai Institute, PO BOX 309, Heriot Bay, BC, V0P 1H0, Canada
| | - Rhea Sanders-Smith
- Botany and Biodiversity Research Centre, University of British Columbia, Unceded xʷməθkʷəýəm (Musqueam) Territory, 3529-6270 University Blvd., Vancouver, BC, V6T 1Z4, Canada.,Hakai Institute, PO BOX 309, Heriot Bay, BC, V0P 1H0, Canada
| | - Emily M Adamczyk
- Zoology and Biodiversity Research Centre, University of British Columbia, Unceded xʷməθkʷəýəm (Musqueam) Territory, 3529-6270 University Blvd., Vancouver, BC, V6T 1Z4, Canada
| | - Coreen Forbes
- Zoology and Biodiversity Research Centre, University of British Columbia, Unceded xʷməθkʷəýəm (Musqueam) Territory, 3529-6270 University Blvd., Vancouver, BC, V6T 1Z4, Canada
| | | | - Mary I O'Connor
- Hakai Institute, PO BOX 309, Heriot Bay, BC, V0P 1H0, Canada.,Zoology and Biodiversity Research Centre, University of British Columbia, Unceded xʷməθkʷəýəm (Musqueam) Territory, 3529-6270 University Blvd., Vancouver, BC, V6T 1Z4, Canada
| | - Laura Wegener Parfrey
- Botany and Biodiversity Research Centre, University of British Columbia, Unceded xʷməθkʷəýəm (Musqueam) Territory, 3529-6270 University Blvd., Vancouver, BC, V6T 1Z4, Canada.,Hakai Institute, PO BOX 309, Heriot Bay, BC, V0P 1H0, Canada.,Zoology and Biodiversity Research Centre, University of British Columbia, Unceded xʷməθkʷəýəm (Musqueam) Territory, 3529-6270 University Blvd., Vancouver, BC, V6T 1Z4, Canada
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13
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Gulick AG, Johnson RA, Pollock CG, Hillis-Starr Z, Bolten AB, Bjorndal KA. Recovery of a large herbivore changes regulation of seagrass productivity in a naturally grazed Caribbean ecosystem. Ecology 2020; 101:e03180. [PMID: 32882749 DOI: 10.1002/ecy.3180] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 05/19/2020] [Accepted: 07/14/2020] [Indexed: 11/05/2022]
Abstract
What happens in meadows after populations of natural grazers rebound following centuries of low abundance? Many seagrass ecosystems are now experiencing this phenomenon with the recovery of green turtles (Chelonia mydas), large-bodied marine herbivores that feed on seagrasses. These seagrass ecosystems provide a rare opportunity to study ecosystem-wide shifts that result from a recovery of herbivores. We evaluate changes in regulation of seagrass productivity in a naturally grazed tropical ecosystem by (1) comparing Thalassia testudinum productivity in grazed and ungrazed areas and (2) evaluating potential regulating mechanisms of T. testudinum productivity. We established 129 green turtle exclusion cages in grazed and ungrazed areas to quantify T. testudinum growth (linear, area, mass, productivity : biomass [P:B]). In each exclosure, we recorded temperature, irradiance, water depth, nitrogen : phosphorus ratio (N:P) of blade tissue, grazing intensity before cage placement, and T. testudinum structural and nutrient characteristics. Thalassia testudinum exhibited compensatory growth in grazed areas via stimulated blade linear growth, blade area growth, and P:B across seasonal high and low growth periods and in shallow (3-4 m) and deep (9-10 m) seagrass meadows. Irradiance, depth, and N:P ratios had significant roles in regulating mass growth and P:B of T. testudinum in ungrazed areas. Depth was a significant regulating factor of mass growth and P:B in grazed areas; rates were higher and more variable in shallow meadows than in deep meadows. Grazing intensity was also a significant regulating factor for P:B, stimulating tissue turnover with increasing grazing pressure. This study provides important insights into how recovery of a large marine herbivore can result in dramatic, sustainable changes in the regulation of seagrass productivity. We also highlight the need for a historical perspective and use of appropriate indicators, including P:B and grazing intensity, when evaluating seagrass response to green turtle grazing as meadows are returned to a natural grazed state. In an age of green turtle recovery and global seagrass decline due to anthropogenic threats, a thorough understanding of green turtle-seagrass interactions at the ecosystem level is critical to ensure the restoration of seagrass ecosystems and continued recovery of green turtle populations.
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Affiliation(s)
- Alexandra G Gulick
- Archie Carr Center for Sea Turtle Research and Department of Biology, University of Florida, Gainesville, Florida, 32611, USA
| | - Robert A Johnson
- Archie Carr Center for Sea Turtle Research and Department of Biology, University of Florida, Gainesville, Florida, 32611, USA
| | - Clayton G Pollock
- Division of Resource Management and Research, Buck Island Reef National Monument, National Park Service, Christiansted, U.S. Virgin Islands, 00820, USA
| | - Zandy Hillis-Starr
- Division of Resource Management and Research, Buck Island Reef National Monument, National Park Service, Christiansted, U.S. Virgin Islands, 00820, USA
| | - Alan B Bolten
- Archie Carr Center for Sea Turtle Research and Department of Biology, University of Florida, Gainesville, Florida, 32611, USA
| | - Karen A Bjorndal
- Archie Carr Center for Sea Turtle Research and Department of Biology, University of Florida, Gainesville, Florida, 32611, USA
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