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Sutera A, Bonaviri C, Spinelli P, Carimi F, De Michele R. Fruit encasing preserves the dispersal potential and viability of stranded Posidonia oceanica seeds. Sci Rep 2024; 14:6218. [PMID: 38486018 PMCID: PMC10940675 DOI: 10.1038/s41598-024-56536-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 03/07/2024] [Indexed: 03/18/2024] Open
Abstract
Posidonia oceanica meadows are the most productive coastal ecosystem in the Mediterranean. Posidonia oceanica seeds are enclosed in buoyant fleshy fruits that allow dispersal. Many fruits eventually strand on beaches, imposing a remarkable energy cost for the plant. This study aims to assess whether stranded seeds retain functional reproductive potential under a variety of environmental conditions. First, we measured the possibility that seeds could be returned to the sea, by tagging fruits and seeds. Second, we quantified the effect of air, sun and heat exposure on the viability and fitness of stranded fruits and naked seeds. The results showed that on average more than half of fruits and seeds are returned to the sea after stranding events and that fruits significantly protect from desiccation and loss of viability. Furthermore, in fruits exposed to the sun and in naked seeds, seedlings development was slower. This study indicates that a significant portion of stranded P. oceanica fruits have a second chance to recruit and develop into young seedlings, relieving the paradox of large energy investment in seed production and apparent low recruitment rate. Additionally, we provide practical indications for seed collection aimed at maximizing seedling production, useful in meadow restoration campaigns.
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Affiliation(s)
- Alberto Sutera
- Institute of Biosciences and Bioresources (IBBR), Italian National Research Council (CNR), Via Ugo la Malfa 153, 90146, Palermo, Italy
| | - Chiara Bonaviri
- Department of Earth and Sea Sciences, University of Palermo, Via Archirafi 22, 90123, Palermo, Italy
- Fano Marine Center, Department of Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, 61032, Fano, Italy
| | - Patrizia Spinelli
- Institute of Biosciences and Bioresources (IBBR), Italian National Research Council (CNR), Via Ugo la Malfa 153, 90146, Palermo, Italy
| | - Francesco Carimi
- Institute of Biosciences and Bioresources (IBBR), Italian National Research Council (CNR), Via Ugo la Malfa 153, 90146, Palermo, Italy
| | - Roberto De Michele
- Institute of Biosciences and Bioresources (IBBR), Italian National Research Council (CNR), Via Ugo la Malfa 153, 90146, Palermo, Italy.
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2
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Crespo D, Faião R, Freitas V, Oliveira VH, Sousa AI, Coelho JP, Dolbeth M. Using seagrass as a nature-based solution: Short-term effects of Zostera noltei transplant in benthic communities of a European Atlantic coastal lagoon. Mar Pollut Bull 2023; 197:115762. [PMID: 37979526 DOI: 10.1016/j.marpolbul.2023.115762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 11/04/2023] [Accepted: 11/06/2023] [Indexed: 11/20/2023]
Abstract
Seagrass meadows provide several ecological functions that improve the overall ecological health of coastal systems and therefore, it is urgent to promote the restoration of such habitats. In Ria de Aveiro, a coastal lagoon in the Atlantic Coast of Portugal, a restoration initiative was responsible for transplanting the dwarf eelgrass Zostera noltei into a highly degraded area. This eelgrass was used as a nature-based solution (NbS) to mitigate some of the impacts of historical mercury contamination. Comparisons of key-species features (density and biomass), and some community-derived indicators (total density and biomass, species richness and Shannon-Wiener index) between the transplanted seagrass patch, their bare vicinities, and their counterpart habitats on the source area, provided signs of the effectiveness of the restoration action on the benthic communities' recovery. Indicators were higher within the restored meadow, and biomass derived indicators of the restored meadow were similar to the source meadow.
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Affiliation(s)
- Daniel Crespo
- CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Novo Edifício do Terminal de Cruzeiros, Avenida General Norton de Matos S/N, 4450-208 Matosinhos, Portugal; CESAM - Centre for Environmental and Marine Studies, Department of Biology, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal.
| | - Rita Faião
- CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Novo Edifício do Terminal de Cruzeiros, Avenida General Norton de Matos S/N, 4450-208 Matosinhos, Portugal
| | - Vânia Freitas
- CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Novo Edifício do Terminal de Cruzeiros, Avenida General Norton de Matos S/N, 4450-208 Matosinhos, Portugal.
| | - Vitor Hugo Oliveira
- CESAM - Centre for Environmental and Marine Studies, Department of Biology, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal.
| | - Ana I Sousa
- CESAM - Centre for Environmental and Marine Studies, Department of Biology, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal.
| | - João Pedro Coelho
- CESAM - Centre for Environmental and Marine Studies, Department of Biology, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal.
| | - Marina Dolbeth
- CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Novo Edifício do Terminal de Cruzeiros, Avenida General Norton de Matos S/N, 4450-208 Matosinhos, Portugal.
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3
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Morris K, Epstein G, Kaiser MJ, Porter J, Johnson AF. Adapting the marine stewardship council's risk-based framework to assess the impact of towed bottom fishing gear on blue carbon habitats. PLoS One 2023; 18:e0288484. [PMID: 37972207 PMCID: PMC10653409 DOI: 10.1371/journal.pone.0288484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 06/28/2023] [Indexed: 11/19/2023] Open
Abstract
Wild capture fisheries are of economic and social importance, providing a primary source of protein to people globally. There is a broad research base on the environmental impacts of fishing gears and processing methods yet, the impact on the global CO2 budget is less well studied. Evaluating the risk that wild capture fisheries pose to ecosystem health is vital to sustainably managing fishing practices to meet increasing global nutritional needs and reverse declines in marine biodiversity. At the same time meeting net-zero ambitions by reducing direct and indirect GHG emissions is vital. Ecological risk assessments, trait-based assessments, and vulnerability assessments have long supported fisheries management systems globally but do not yet provide any representation regarding the impacts that fishing gears have on the ability of the habitat to capture and store carbon. Considering the importance of accessibility and transparency in approaches necessary for fisheries sustainability certifications, this paper describes a method to integrate habitat carbon capacity attributes into the Marine Stewardship Council (MSC) Consequence and Spatial Analysis (CSA) framework. Applying the CSA carbon extension developed herein produces different CSA risk scores compared to the MSC CSA that does not account for carbon. This has potential consequences for certification schemes as carbon becomes more important in the fisheries sustainability conversation. The CSA carbon extension tool developed here is an important first step in incorporating carbon indicators into evaluations of fisheries that consider fishery carbon impacts.
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Affiliation(s)
- Kate Morris
- The Lyell Centre, Heriot-Watt University, Edinburgh, Scotland, United Kingdom
| | - Graham Epstein
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Cornwall, United Kingdom
- University of Victoria, Victoria, British Columbia, Canada
| | - Michel J. Kaiser
- The Lyell Centre, Heriot-Watt University, Edinburgh, Scotland, United Kingdom
| | - Joanne Porter
- International Centre for Island Technology, Heriot-Watt University Orkney, Stromness, Orkney, Scotland, United Kingdom
| | - Andrew F. Johnson
- The Lyell Centre, Heriot-Watt University, Edinburgh, Scotland, United Kingdom
- MarFishEco Fisheries Consultants Ltd, Edinburgh, Scotland, United Kingdom
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4
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Litsi-Mizan V, Efthymiadis PT, Gerakaris V, Serrano O, Tsapakis M, Apostolaki ET. Decline of seagrass (Posidonia oceanica) production over two decades in the face of warming of the Eastern Mediterranean Sea. New Phytol 2023; 239:2126-2137. [PMID: 37366062 DOI: 10.1111/nph.19084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 05/31/2023] [Indexed: 06/28/2023]
Abstract
The response of Posidonia oceanica meadows to global warming of the Eastern Mediterranean Sea, where the increase in sea surface temperature (SST) is particularly severe, is poorly investigated. Here, we reconstructed the long-term P. oceanica production in 60 meadows along the Greek Seas over two decades (1997-2018), using lepidochronology. We determined the effect of warming on production by reconstructing the annual and maximum (i.e. August) SST, considering the role of other production drivers related to water quality (i.e. Chla, suspended particulate matter, Secchi depth). Grand mean (±SE) production across all sites and the study period was 48 ± 1.1 mg DW per shoot yr-1 . Production over the last two decades followed a trajectory of decrease, which was related to the concurrent increase in annual SST and SSTaug . Annual SST > 20°C and SSTaug > 26.5°C was related to production decline (GAMM, P < 0.05), while the rest of the tested factors did not help explain the production pattern. Our results indicate a persistent and increasing threat for Eastern Mediterranean meadows, drawing attention to management authorities, highlighting the necessity of reducing local impacts to enhance the resilience of seagrass meadows to global change threats.
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Affiliation(s)
- Victoria Litsi-Mizan
- Biology Department, University of Crete, Voutes University Campus, PO Box 2208, Heraklion, Crete, GR-70013, Greece
- Institute of Oceanography, Hellenic Centre for Marine Research, PO Box 2214, Heraklion, Crete, GR-71003, Greece
| | - Pavlos T Efthymiadis
- Institute of Oceanography, Hellenic Centre for Marine Research, PO Box 2214, Heraklion, Crete, GR-71003, Greece
| | - Vasilis Gerakaris
- Institute of Oceanography, Hellenic Centre for Marine Research, PO Box 712, Anavyssos, Attiki, 19013, Greece
| | - Oscar Serrano
- Centre of Advanced Studies of Blanes (CEAB-CSIC), Cala Sant Francesc 14, Blanes, 17300, Spain
- School of Science & Centre for Marine Ecosystems Research, Edith Cowan University, Joondalup, WA, 6027, Australia
| | - Manolis Tsapakis
- Institute of Oceanography, Hellenic Centre for Marine Research, PO Box 2214, Heraklion, Crete, GR-71003, Greece
| | - Eugenia T Apostolaki
- Institute of Oceanography, Hellenic Centre for Marine Research, PO Box 2214, Heraklion, Crete, GR-71003, Greece
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5
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Pansini A, Beca-Carretero P, González MJ, La Manna G, Medina I, Ceccherelli G. Sources of variability in seagrass fatty acid profiles and the need of identifying reliable warming descriptors. Sci Rep 2023; 13:10000. [PMID: 37340008 DOI: 10.1038/s41598-023-36498-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 06/05/2023] [Indexed: 06/22/2023] Open
Abstract
Global warming is expected to have inexorable and profound effects on marine ecosystems, particularly in foundation species such as seagrasses. Identifying responses to warming and comparing populations across natural temperature gradients can inform how future warming will impact the structure and function of ecosystems. Here, we investigated how thermal environment, intra-shoot and spatial variability modulate biochemical responses of the Mediterranean seagrass Posidonia oceanica. Through a space-for-time substitution study, Fatty acid (FA) profiles on the second and fifth leaf of the shoots were quantified at eight sites in Sardinia along a natural sea surface temperature (SST) summer gradient (about 4 °C). Higher mean SST were related to a decrease in the leaf total fatty acid content (LTFA), a reduction in polyunsaturated fatty acids (PUFA), omega-3/omega-6 PUFA and PUFA/saturated fatty acids (SFA) ratios and an increase in SFA, monounsaturated fatty acids and carbon elongation index (CEI, C18:2 n-6/C16:2 n-6) ratio. Results also revealed that FA profiles were strongly influenced by leaf age, independently of SST and spatial variability within sites. Overall, this study evidenced that the sensitive response of P. oceanica FA profiles to intra-shoot and spatial variability must not be overlooked when considering their response to temperature changes.
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Affiliation(s)
- Arianna Pansini
- Dipartimento di Scienze Chimiche Fisiche Matematiche e Naturali, Università Degli Studi di Sassari, Via Piandanna 4, 07100, Sassari, Italy.
| | - Pedro Beca-Carretero
- Department of Oceanography, Instituto de Investigacións Mariñas (IIM-CSIC), 36208, Vigo, Spain
| | - Maria J González
- Department of Oceanography, Instituto de Investigacións Mariñas (IIM-CSIC), 36208, Vigo, Spain
| | - Gabriella La Manna
- Dipartimento di Scienze Chimiche Fisiche Matematiche e Naturali, Università Degli Studi di Sassari, Via Piandanna 4, 07100, Sassari, Italy
- MareTerra Onlus, Environmental Research and Conservation, 07041, Alghero, SS, Italy
| | - Isabel Medina
- Department of Oceanography, Instituto de Investigacións Mariñas (IIM-CSIC), 36208, Vigo, Spain
| | - Giulia Ceccherelli
- Dipartimento di Scienze Chimiche Fisiche Matematiche e Naturali, Università Degli Studi di Sassari, Via Piandanna 4, 07100, Sassari, Italy
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6
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Leblanc ML, O'Connor MI, Kuzyk ZZA, Noisette F, Davis KE, Rabbitskin E, Sam LL, Neumeier U, Costanzo R, Ehn JK, Babb D, Idrobo CJ, Gilbert JP, Leblon B, Humphries MM. Limited recovery following a massive seagrass decline in subarctic eastern Canada. Glob Chang Biol 2023; 29:432-450. [PMID: 36270797 DOI: 10.1111/gcb.16499] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 09/02/2022] [Accepted: 09/16/2022] [Indexed: 06/16/2023]
Abstract
Over the last few decades, there has been an increasing recognition for seagrasses' contribution to the functioning of nearshore ecosystems and climate change mitigation. Nevertheless, seagrass ecosystems have been deteriorating globally at an accelerating rate during recent decades. In 2017, research into the condition of eelgrass (Zostera marina) along the eastern coast of James Bay, Canada, was initiated in response to reports of eelgrass decline by the Cree First Nations of Eeyou Istchee. As part of this research, we compiled and analyzed two decades of eelgrass cover data and three decades of eelgrass monitoring data (biomass and density) to detect changes and assess possible environmental drivers. We detected a major decline in eelgrass condition between 1995 and 1999, which encompassed the entire east coast of James Bay. Surveys conducted in 2019 and 2020 indicated limited changes post-decline, for example, low eelgrass cover (<25%), low aboveground biomass, smaller shoots than before 1995, and marginally low densities persisted at most sites. Overall, the synthesized datasets show a 40% loss of eelgrass meadows with >50% cover in eastern James Bay since 1995, representing the largest scale eelgrass decline documented in eastern Canada since the massive die-off event that occurred in the 1930s along the North Atlantic coast. Using biomass data collected since 1982, but geographically limited to the sector of the coast near the regulated La Grande River, generalized additive modeling revealed eelgrass meadows are affected by local sea surface temperature, early ice breakup, and higher summer freshwater discharge. Our results caution against assuming subarctic seagrass ecosystems have avoided recent global declines or will benefit from ongoing climate warming.
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Affiliation(s)
- Mélanie-Louise Leblanc
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Mary I O'Connor
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Zou Zou A Kuzyk
- Centre for Earth Observation Science (CEOS), University of Manitoba, Winnipeg, Manitoba, Canada
| | - Fanny Noisette
- Institut des sciences de la mer de Rimouski, Université du Québec à Rimouski, Rimouski, Québec, Canada
| | - Kaleigh E Davis
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | | | | | - Urs Neumeier
- Institut des sciences de la mer de Rimouski, Université du Québec à Rimouski, Rimouski, Québec, Canada
| | - Rémi Costanzo
- Institut des sciences de la mer de Rimouski, Université du Québec à Rimouski, Rimouski, Québec, Canada
| | - Jens K Ehn
- Centre for Earth Observation Science (CEOS), University of Manitoba, Winnipeg, Manitoba, Canada
| | - David Babb
- Centre for Earth Observation Science (CEOS), University of Manitoba, Winnipeg, Manitoba, Canada
| | - C Julián Idrobo
- Aurora College, Thebacha Campus, Fort Smith, Northwest Territories, Canada
| | | | - Brigitte Leblon
- Faculty of Forestry and Environmental Management, University of New Brunswick, Fredericton, New Brunswick, Canada
| | - Murray M Humphries
- Department of Natural Resource Sciences, McGill University, Montréal, Québec, Canada
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7
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Pastor A, Ospina-Alvarez A, Larsen J, Thorbjørn Hansen F, Krause-Jensen D, Maar M. A network analysis of connected biophysical pathways to advice eelgrass (Zostera marina) restoration. Mar Environ Res 2022; 179:105690. [PMID: 35853313 DOI: 10.1016/j.marenvres.2022.105690] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 06/17/2022] [Accepted: 06/20/2022] [Indexed: 06/15/2023]
Abstract
The North Sea and the Baltic Sea, including Danish coastal waters, have experienced a drastic decline in eelgrass Zostera marina coverage during the past century. Around 1900, eelgrass meadows covered about 6700 km2 of Danish coastal waters while the current potential distribution area is only about one third of this. In some areas, the potential distribution area is far from realized, and restoration efforts are needed to assist recovery. Such efforts are challenging, and resource-demanding and careful site selection is, therefore, important. In the present study, we aim to identify the connectivity of eelgrass populations as a basis for guiding site selection for restoration. We developed a coupled biophysical model to study eelgrass dispersal in the Kattegat. Partly submerged particles simulated the dispersal of reproductive eelgrass shoots containing seeds during the flowering season July-September. We then used network analysis to identify the potential connectivity between populations. We evaluated connectivity based on In-strength, Betweenness and Eigenvector centrality metrics and identified key areas in the Kattegat such as the central part of Aalborg Bay, to be considered to restore the network of Z. marina patches. The study proves the potentials of combining hydrodynamic models and network analysis to support marine conservation and planning, and highlights the importance of collaboration between ecologists, oceanographers, and practitioners in this endeavour.
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Affiliation(s)
- Ane Pastor
- Department of Ecoscience, Aarhus University, Frederiksborgvej 399, 4000, Roskilde, Denmark.
| | - Andrés Ospina-Alvarez
- Mediterranean Institute for Advanced Studies IMEDEA (UIB-CSIC), C/ Miquel Marquès, 21, 07190, Esporles, Balearic Islands, Spain
| | - Janus Larsen
- Department of Ecoscience, Aarhus University, Frederiksborgvej 399, 4000, Roskilde, Denmark
| | - Flemming Thorbjørn Hansen
- Section for Coastal Ecology, Technical University of Denmark, Kemitorvet, Building 201, 2800 kgs, Lyngby, Denmark
| | | | - Marie Maar
- Department of Ecoscience, Aarhus University, Frederiksborgvej 399, 4000, Roskilde, Denmark
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Turschwell MP, Connolly RM, Dunic JC, Sievers M, Buelow CA, Pearson RM, Tulloch VJD, Côté IM, Unsworth RKF, Collier CJ, Brown CJ. Anthropogenic pressures and life history predict trajectories of seagrass meadow extent at a global scale. Proc Natl Acad Sci U S A 2021; 118:e2110802118. [PMID: 34725160 DOI: 10.1073/pnas.2110802118] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 09/17/2021] [Indexed: 12/14/2022] Open
Abstract
Seagrass meadows are threatened by multiple pressures, jeopardizing the many benefits they provide to humanity and biodiversity, including climate regulation and food provision through fisheries production. Conservation of seagrass requires identification of the main pressures contributing to loss and the regions most at risk of ongoing loss. Here, we model trajectories of seagrass change at the global scale and show they are related to multiple anthropogenic pressures but that trajectories vary widely with seagrass life-history strategies. Rapidly declining trajectories of seagrass meadow extent (>25% loss from 2000 to 2010) were most strongly associated with high pressures from destructive demersal fishing and poor water quality. Conversely, seagrass meadow extent was more likely to be increasing when these two pressures were low. Meadows dominated by seagrasses with persistent life-history strategies tended to have slowly changing or stable trajectories, while those with opportunistic species were more variable, with a higher probability of either rapidly declining or rapidly increasing. Global predictions of regions most at risk for decline show high-risk areas in Europe, North America, Japan, and southeast Asia, including places where comprehensive long-term monitoring data are lacking. Our results highlight where seagrass loss may be occurring unnoticed and where urgent conservation interventions are required to reverse loss and sustain their essential services.
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Dunic JC, Brown CJ, Connolly RM, Turschwell MP, Côté IM. Long-term declines and recovery of meadow area across the world's seagrass bioregions. Glob Chang Biol 2021; 27:4096-4109. [PMID: 33993580 DOI: 10.1111/gcb.15684] [Citation(s) in RCA: 67] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 04/08/2021] [Accepted: 04/17/2021] [Indexed: 06/12/2023]
Abstract
As human impacts increase in coastal regions, there is concern that critical habitats that provide the foundation of entire ecosystems are in decline. Seagrass meadows face growing threats such as poor water quality and coastal development. To determine the status of seagrass meadows over time, we reconstructed time series of meadow area from 175 studies that surveyed 547 sites around the world. We found an overall trajectory of decline in all seven bioregions with a global net loss of 5602 km2 (19.1% of surveyed meadow area) occurring since 1880. Declines have typically been non-linear, with rapid and historical losses observed in several bioregions. The greatest net losses of area occurred in four bioregions (Tropical Atlantic, Temperate North Atlantic East, Temperate Southern Oceans and Tropical Indo-Pacific), with declining trends being the slowest and most consistent in the latter two bioregions. In some bioregions, trends have recently stabilised or reversed. Losses, however, still outweigh gains. Despite consistent global declines, meadows show high variability in trajectories, within and across bioregions, highlighting the importance of local context. Studies identified 12 different drivers of meadow area change, with coastal development and water quality as the most commonly cited. Overall, however, attributions were primarily descriptive and only 10% of studies used inferential attributions. Although ours is the most comprehensive dataset to date, it still represents only one-tenth of known global seagrass extent, with conspicuous historical and geographic biases in sampling. It therefore remains unclear whether the bioregional patterns of change documented here reflect changes in the world's unmonitored seagrass meadows. The variability in seagrass meadow trajectories, and the attribution of change to numerous drivers, suggest we urgently need to improve understanding of the causes of seagrass meadow loss if we are to improve local-scale management.
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Affiliation(s)
- Jillian C Dunic
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Canada
| | - Christopher J Brown
- Coastal and Marine Research Centre, Australian Rivers Institute, School of Environment and Science, Griffith University, Gold Coast, Qld, Australia
| | - Rod M Connolly
- Coastal and Marine Research Centre, Australian Rivers Institute, School of Environment and Science, Griffith University, Gold Coast, Qld, Australia
| | - Mischa P Turschwell
- Coastal and Marine Research Centre, Australian Rivers Institute, School of Environment and Science, Griffith University, Gold Coast, Qld, Australia
| | - Isabelle M Côté
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Canada
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10
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Helber SB, Winters G, Stuhr M, Belshe EF, Bröhl S, Schmid M, Reuter H, Teichberg M. Nutrient History Affects the Response and Resilience of the Tropical Seagrass Halophila stipulacea to Further Enrichment in Its Native Habitat. Front Plant Sci 2021; 12:678341. [PMID: 34421939 PMCID: PMC8374242 DOI: 10.3389/fpls.2021.678341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 07/12/2021] [Indexed: 06/13/2023]
Abstract
Eutrophication is one of the main threats to seagrass meadows, but there is limited knowledge on the interactive effects of nutrients under a changing climate, particularly for tropical seagrass species. This study aimed to detect the onset of stress in the tropical seagrass, Halophila stipulacea, by investigating the effect of in situ nutrient addition during an unusually warm summer over a 6-month period. We measured a suite of different morphological and biochemical community metrics and individual plant traits from two different sites with contrasting levels of eutrophication history before and after in situ fertilization in the Gulf of Aqaba. Nutrient stress combined with summer temperatures that surpassed the threshold for optimal growth negatively affected seagrass plants from South Beach (SB), an oligotrophic marine protected area, while H. stipulacea populations from North Beach (NB), a eutrophic and anthropogenically impacted area, benefited from the additional nutrient input. Lower aboveground (AG) and belowground (BG) biomass, reduced Leaf Area Index (LAI), smaller internodal distances, high sexual reproductive effort and the increasing occurrence of apical shoots in seagrasses from SB sites indicated that the plants were under stress and not growing under optimal conditions. Moreover, AG and BG biomass and internodal distances decreased further with the addition of fertilizer in SB sites. Results presented here highlight the fact that H. stipulacea is one of the most tolerant and plastic seagrass species. Our study further demonstrates that the effects of fertilization differ significantly between meadows that are growing exposed to different levels of anthropogenic pressures. Thus, the meadow's "history" affects it resilience and response to further stress. Our results suggest that monitoring efforts on H. stipulacea populations in its native range should focus especially on carbohydrate reserves in leaves and rhizomes, LAI, internodal length and percentage of apical shoots as suitable warning indicators for nutrient stress in this seagrass species to minimize future impacts on these valuable ecosystems.
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Affiliation(s)
- Stephanie B. Helber
- Leibniz Centre for Tropical Marine Research (ZMT) GmbH, Bremen, Germany
- Institute for Chemistry and Biology of the Marine Environment (ICBM), Oldenburg, Germany
| | - Gidon Winters
- The Dead Sea and Arava Science Center (ADSSC), Jerusalem, Israel
- Ben-Gurion University of the Negev, Eilat, Israel
| | - Marleen Stuhr
- Tropical Coral Ecophysiology, Interuniversity Institute for Marine Sciences - Eilat (IUI), Eilat, Israel
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University (BIU), Ramat Gan, Israel
| | - E. F. Belshe
- Leibniz Centre for Tropical Marine Research (ZMT) GmbH, Bremen, Germany
| | - Stefanie Bröhl
- Leibniz Centre for Tropical Marine Research (ZMT) GmbH, Bremen, Germany
| | - Michael Schmid
- Leibniz Centre for Tropical Marine Research (ZMT) GmbH, Bremen, Germany
| | - Hauke Reuter
- Leibniz Centre for Tropical Marine Research (ZMT) GmbH, Bremen, Germany
- Faculty for Biology and Chemistry, University of Bremen, Bremen, Germany
| | - Mirta Teichberg
- Leibniz Centre for Tropical Marine Research (ZMT) GmbH, Bremen, Germany
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Thomson AI, Archer FI, Coleman MA, Gajardo G, Goodall‐Copestake WP, Hoban S, Laikre L, Miller AD, O’Brien D, Pérez‐Espona S, Segelbacher G, Serrão EA, Sjøtun K, Stanley MS. Charting a course for genetic diversity in the UN Decade of Ocean Science. Evol Appl 2021; 14:1497-1518. [PMID: 34178100 PMCID: PMC8210796 DOI: 10.1111/eva.13224] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 03/04/2021] [Accepted: 03/04/2021] [Indexed: 02/06/2023] Open
Abstract
The health of the world's oceans is intrinsically linked to the biodiversity of the ecosystems they sustain. The importance of protecting and maintaining ocean biodiversity has been affirmed through the setting of the UN Sustainable Development Goal 14 to conserve and sustainably use the ocean for society's continuing needs. The decade beginning 2021-2030 has additionally been declared as the UN Decade of Ocean Science for Sustainable Development. This program aims to maximize the benefits of ocean science to the management, conservation, and sustainable development of the marine environment by facilitating communication and cooperation at the science-policy interface. A central principle of the program is the conservation of species and ecosystem components of biodiversity. However, a significant omission from the draft version of the Decade of Ocean Science Implementation Plan is the acknowledgment of the importance of monitoring and maintaining genetic biodiversity within species. In this paper, we emphasize the importance of genetic diversity to adaptive capacity, evolutionary potential, community function, and resilience within populations, as well as highlighting some of the major threats to genetic diversity in the marine environment from direct human impacts and the effects of global climate change. We then highlight the significance of ocean genetic diversity to a diverse range of socioeconomic factors in the marine environment, including marine industries, welfare and leisure pursuits, coastal communities, and wider society. Genetic biodiversity in the ocean, and its monitoring and maintenance, is then discussed with respect to its integral role in the successful realization of the 2030 vision for the Decade of Ocean Science. Finally, we suggest how ocean genetic diversity might be better integrated into biodiversity management practices through the continued interaction between environmental managers and scientists, as well as through key leverage points in industry requirements for Blue Capital financing and social responsibility.
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Affiliation(s)
| | | | - Melinda A. Coleman
- New South Wales FisheriesNational Marine Science CentreCoffs HarbourNSWAustralia
- National Marine Science CentreSouthern Cross UniversityCoffs HarbourNSWAustralia
- Oceans Institute and School of Biological SciencesUniversity of Western AustraliaCrawleyWAAustralia
| | - Gonzalo Gajardo
- Laboratory of Genetics, Aquaculture & BiodiversityUniversidad de Los LagosOsornoChile
| | | | - Sean Hoban
- Centre for Tree ScienceThe Morton ArboretumLisleILUSA
| | - Linda Laikre
- Centre for Tree ScienceThe Morton ArboretumLisleILUSA
- The Wildlife Analysis UnitThe Swedish Environmental Protection AgencyStockholmSweden
| | - Adam D. Miller
- School of Life and Environmental SciencesCentre for Integrative EcologyDeakin UniversityGeelongVicAustralia
- Deakin Genomics CentreDeakin UniversityGeelongVic.Australia
| | | | - Sílvia Pérez‐Espona
- The Royal (Dick) School of Veterinary Studies and The Roslin InstituteMidlothianUK
| | - Gernot Segelbacher
- Chair of Wildlife Ecology and ManagementUniversity FreiburgFreiburgGermany
| | - Ester A. Serrão
- CCMARCentre of Marine SciencesFaculty of Sciences and TechnologyUniversity of AlgarveFaroPortugal
| | - Kjersti Sjøtun
- Department of Biological SciencesUniversity of BergenBergenNorway
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Premarathne C, Jiang Z, He J, Fang Y, Chen Q, Cui L, Wu Y, Liu S, Chunyu Z, Vijerathna P, Huang X. Low Light Availability Reduces the Subsurface Sediment Carbon Content in Halophila beccarii From the South China Sea. Front Plant Sci 2021; 12:664060. [PMID: 34163504 PMCID: PMC8215720 DOI: 10.3389/fpls.2021.664060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 04/16/2021] [Indexed: 05/15/2023]
Abstract
Eutrophication, dredging, agricultural and urban runoffs, and epiphyte overgrowth could reduce light availability for seagrass. This may affect "blue carbon" stocks in seagrass beds. However, little research is available on the effect of light intensities on carbon sequestration capacity in seagrass beds, especially small-bodied seagrasses. The dominant seagrass Halophila beccarii, a vulnerable species on the IUCN Red List, was cultured in different light intensities to examine the response of vegetation and sediment carbon in seagrass beds. The results showed that low light significantly reduced leaf length and above-ground biomass, while carbon content in both above-ground and below-ground tissues were not affected. Low light reduced both the above-ground biomass carbon and the total biomass carbon. Interestingly, while under saturating light conditions, the subsurface and surface carbon content was similar, under low light conditions, subsurface sediment carbon was significantly lower than the surface content. The reduction of subsurface sediment carbon might be caused by less release flux of dissolved organic carbon from roots in low light. Taken together, these results indicate that reduced light intensities, to which these meadows are exposed to, will reduce carbon sequestration capacity in seagrass beds. Measures should be taken to eliminate the input of nutrients on seagrass meadows and dredging activities to maintain the "blue carbon" storage service by enhancing light penetration into seagrass.
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Affiliation(s)
- Chanaka Premarathne
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Zhijian Jiang
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
- University of Chinese Academy of Sciences, Beijing, China
- Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, China
- Innovation Academy of South China Sea Ecology and Environmental Engineering, Chinese Academy of Sciences, Guangzhou, China
- *Correspondence: Zhijian Jiang,
| | - Jialu He
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yang Fang
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Qiming Chen
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Lijun Cui
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yunchao Wu
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
- Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, China
- Innovation Academy of South China Sea Ecology and Environmental Engineering, Chinese Academy of Sciences, Guangzhou, China
| | - Songlin Liu
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
- Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, China
- Innovation Academy of South China Sea Ecology and Environmental Engineering, Chinese Academy of Sciences, Guangzhou, China
| | - Zhao Chunyu
- College of Resources, Environment and Planning, Dezhou University, Dezhou, China
| | | | - Xiaoping Huang
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
- University of Chinese Academy of Sciences, Beijing, China
- Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, China
- Innovation Academy of South China Sea Ecology and Environmental Engineering, Chinese Academy of Sciences, Guangzhou, China
- Xiaoping Huang,
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