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Guo S, Li J, Yang X, Qin Y, Zhao Y, Wei J, Ma H, Yu Z, Zhao L, Zhang Y. Resistance of an intertidal oyster(Saccostrea mordax)to marine heatwaves and the implication for reef building. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 928:172474. [PMID: 38621527 DOI: 10.1016/j.scitotenv.2024.172474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2023] [Revised: 02/01/2024] [Accepted: 04/12/2024] [Indexed: 04/17/2024]
Abstract
Marine heatwaves (MHWs) have a significant impact on intertidal bivalves and the ecosystems they sustain, causing the destruction of organisms' original habitats. Saccostrea mordax mainly inhabits the intertidal zone around the equator, exhibiting potential tolerance to high temperatures and maybe a species suitable for habitat restoration. However, an understanding about the tolerance mechanism of S. mordax to high temperatures is unclear. It is also unknown the extent to which S. mordax can tolerate repeated heatwaves of increasing intensity and frequency. Here, we simulated the effects of two scenarios of MHWs and measured the physiological and biochemical responses and gene expression spectrum of S. mordax. The predicted responses varied greatly across heatwaves, and no heatwave had a significant impact on the survival of S. mordax. Specifically, there were no statistically significant changes apparent in the standard metabolic rate and the activities of enzymes of the oyster during repeated heatwaves. S. mordax exposed to high-intensity heatwaves enhanced their standard metabolic rate to fuel essential physiological maintenance and increasing activity of SOD and expression of HSP70/90. These strategies are presumably at the expense of functions related to immunity and growth, as best exemplified by significant depressions in activities of enzymes (NaK, CaMg, T-ATP, and AKP) and expression levels of genes (Rab, eEF-2, HMGR, Rac1, SGK, Rab8, etc.). The performance status of S. mordax tends to improve by implementing a suite of less energy-costly compensatory mechanisms at various levels of biological organization when re-exposed to heatwaves. The adaptive abilities shown by S. mordax indicate that they can play a crucial role in the restoration of oyster reefs in tropical seas.
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Affiliation(s)
- Shuming Guo
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Innovation Academy of South China Sea Ecology and Environmental Engineering, Chinese Academy of Science, Guangzhou 510301, China; University of the Chinese Academy of Sciences, Beijing 100049, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; Hainan Provincial Key Laboratory of Tropical Marine Biology Technology, Sanya Marine Eco-environment Engineering Research Institute, Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya 572024, China
| | - Jun Li
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Innovation Academy of South China Sea Ecology and Environmental Engineering, Chinese Academy of Science, Guangzhou 510301, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; Hainan Provincial Key Laboratory of Tropical Marine Biology Technology, Sanya Marine Eco-environment Engineering Research Institute, Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya 572024, China
| | - Xiaogang Yang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Innovation Academy of South China Sea Ecology and Environmental Engineering, Chinese Academy of Science, Guangzhou 510301, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; Hainan Provincial Key Laboratory of Tropical Marine Biology Technology, Sanya Marine Eco-environment Engineering Research Institute, Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya 572024, China
| | - Yanping Qin
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Innovation Academy of South China Sea Ecology and Environmental Engineering, Chinese Academy of Science, Guangzhou 510301, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; Hainan Provincial Key Laboratory of Tropical Marine Biology Technology, Sanya Marine Eco-environment Engineering Research Institute, Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya 572024, China
| | - Yuexin Zhao
- Dalian Ocean University, Dalian 116023, China
| | - Jinkuan Wei
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Innovation Academy of South China Sea Ecology and Environmental Engineering, Chinese Academy of Science, Guangzhou 510301, China; University of the Chinese Academy of Sciences, Beijing 100049, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; Hainan Provincial Key Laboratory of Tropical Marine Biology Technology, Sanya Marine Eco-environment Engineering Research Institute, Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya 572024, China
| | - Haitao Ma
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Innovation Academy of South China Sea Ecology and Environmental Engineering, Chinese Academy of Science, Guangzhou 510301, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; Hainan Provincial Key Laboratory of Tropical Marine Biology Technology, Sanya Marine Eco-environment Engineering Research Institute, Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya 572024, China
| | - Ziniu Yu
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Innovation Academy of South China Sea Ecology and Environmental Engineering, Chinese Academy of Science, Guangzhou 510301, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; Hainan Provincial Key Laboratory of Tropical Marine Biology Technology, Sanya Marine Eco-environment Engineering Research Institute, Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya 572024, China
| | - Liqiang Zhao
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Innovation Academy of South China Sea Ecology and Environmental Engineering, Chinese Academy of Science, Guangzhou 510301, China; Guangdong Ocean University, Zhangjiang 524088, China.
| | - Yuehuan Zhang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Innovation Academy of South China Sea Ecology and Environmental Engineering, Chinese Academy of Science, Guangzhou 510301, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; Hainan Provincial Key Laboratory of Tropical Marine Biology Technology, Sanya Marine Eco-environment Engineering Research Institute, Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya 572024, China.
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Filippini G, Dafforn KA, Bugnot AB. Shellfish as a bioremediation tool: A review and meta-analysis. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 316:120614. [PMID: 36356885 DOI: 10.1016/j.envpol.2022.120614] [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: 05/26/2022] [Revised: 10/17/2022] [Accepted: 11/04/2022] [Indexed: 06/16/2023]
Abstract
Over the last century, human activities have increased the amount of nutrients inputs to terrestrial and aquatic ecosystems. These activities have altered nitrogen (N) and phosphorus (P) cycling, causing substantial changes in ecosystem function such as provision of clean air and water. Strategies that reduce and remove excess nutrients are urgently needed to remediate impacted systems. Reef-forming shellfish (oysters and mussels) can play a crucial role in nutrient cycling, particularly in N removal from aquatic systems by providing substrate for microbial colonisation and enhancing microbial denitrification in the surrounding sediments. However, the potential for shellfish to enhance nutrient cycling (and denitrification) will likely vary spatially and in response to several environmental factors. Here, we used 1) a qualitative analysis to review nutrient processes occurring on shellfish; and 2) a meta-analysis to evaluate the influence of shellfish on benthic metabolism and nutrient cycling in surrounding sediments, and how that is influenced by environmental factors such as grain size, seasonality, water body type, and tidal position. Overall, we found that shellfish increased oxygen consumption, with consequent release of ammonia (NH4+) and phosphate (PO43-) from shellfish and their surrounding sediments. These parameters did not depend on grain size, water body type and tidal height, but the release of PO43- was variable between seasons, being highest during summer and autumn. Shellfish presence also enhanced denitrification measured as dinitrogen gas (N2) efflux on both reefs and sediments. Denitrification was highest in lagoons; in sandy sediments; and during the warmest season (summer). Thus, our findings highlight that environmental context can mediate the effects of shellfish reefs on sediment function. This information is important for managers seeking to use these animals as an effective bioremediation tool.
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Affiliation(s)
- Giulia Filippini
- School of Natural Sciences, Macquarie University, North Ryde, NSW, 2109, Australia.
| | - Katherine A Dafforn
- School of Natural Sciences, Macquarie University, North Ryde, NSW, 2109, Australia; Sydney Institute of Marine Science, Mosman, NSW, 2088, Australia
| | - Ana B Bugnot
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, 2006, Australia; Commonwealth Scientific and Industrial Research Organisation, Brisbane, QLD, 4001, Australia
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Amato J, Alberti J, Martin S, Temple N, Sparks E, Cebrian J. Do small-scale saltmarsh planting living shoreline projects enhance coastal functionality? A case study in the Northern Gulf of Mexico. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 321:116025. [PMID: 36029632 DOI: 10.1016/j.jenvman.2022.116025] [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: 09/01/2021] [Revised: 06/16/2022] [Accepted: 08/13/2022] [Indexed: 06/15/2023]
Abstract
Human coastal occupation often leads to the degradation of the structural properties and environmental functions of natural coastlines. . Much research has been done on the cost-effectiveness of various living shorelines designs, however more work is needed for simple, small-scale designs that are typically adopted in waterfront residential or recreational properties. To contribute to this gap, we planted small-scale plots of black needlerush (Juncus roemerianus) in two sites, one in a residential property and another one in a recreational property in the Northern Gulf of Mexico that experienced significant wave energy. Plots were planted at two different densities (50% or 100% initial cover) or left unplanted (controls) and, along with monitoring the evolution of the planted salt marsh, we measured a number of functional metrics including soil slope, abundance of nekton within and in front of the plots, and cover of submerged aquatic vegetation (SAV) in front of the plots monthly over two years. In one of the sites plant cover decreased precipitously, and in the other site we did not observe any significant changes in plant cover over time (i.e. the initial 50% and 100% plantings remained at that level throughout the experiment) despite protecting the planted salt marsh with coir logs. We did not find any changes in soil slope or nekton abundance between planted and control plots. SAV growth was restrained in front of planted plots in relation to control plots, possibly due to deleterious impacts by the coir logs. Overall, the results suggest the protection against wave energy attained in this experiment is insufficient for adequate saltmarsh establishment and growth, thereby encountering decreasing or stationary plant density and no significant differences in soil slope or nekton abundance between planted and non-planted plots. Our results indicate the adoption of small-scale saltmarsh planting to reduce erosion and enhance coastal functionality needs to ensure that wave energy is sufficiently dampened for adequate saltmarsh growth and, concomitantly, the conceived saltmarsh protection mechanism does not negatively impact adjacent SAV.
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Affiliation(s)
- Jamie Amato
- Department of Marine Sciences, University of South Alabama, LSCB 25, Mobile, AL, 36688, USA; Dauphin Island Sea Lab, 101 Bienville Boulevard, Dauphin Island, AL, 36528, USA
| | - Juan Alberti
- Instituto de Investigaciones Marinas y Costeras (IIMyC). FCEyN. Universidad Nacional de Mar Del Plata-CONICET. CC 1260, Funes 3250, 7600, Mar Del Plata, Argentina
| | - Sara Martin
- Coastal Research and Extension Center, Mississippi State University, 1815 Popps Ferry Road, Biloxi, MS, 39532, USA; Mississippi-Alabama Sea Grant Consortium, 703 East Beach Drive, Ocean Springs, MS, 39564, USA
| | - Nigel Temple
- WSP USA, 11 N Water Street, Mobile, AL, 36602, USA
| | - Eric Sparks
- Coastal Research and Extension Center, Mississippi State University, 1815 Popps Ferry Road, Biloxi, MS, 39532, USA; Mississippi-Alabama Sea Grant Consortium, 703 East Beach Drive, Ocean Springs, MS, 39564, USA; Department of Wildlife, Fisheries, and Aquaculture, Mississippi State University, Mississippi State, MS, 39762, USA
| | - Just Cebrian
- Northern Gulf Institute, Mississippi State University, 1021 Balch Blvd, Stennis Space Center, MS, 39529, USA.
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Aiken CM, Mulloy R, Dwane G, Jackson EL. Working With Nature Approaches for the Creation of Soft Intertidal Habitats. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.682349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
As the artificial defenses often required for urban and industrial development, such as seawalls, breakwaters, and bund walls, directly replace natural habitats, they may produce population fragmentation and a disruption of ecological connectivity, compromising the delivery of ecosystem services. Such problems have increasingly been addressed through “Working with Nature” (WwN) techniques, wherein natural features such as species and habitats are included as additional functional components within the design of built infrastructure. There now exists a convincing body of empirical evidence that WwN techniques can enhance the structural integrity of coastal works, and at the same time promote biodiversity and ecosystem services. While these benefits have often been achieved through modification of the hard surfaces of the coastal defense structures themselves, the desired ecological and engineering goals may often demand the creation of new soft substrates from sediment. Here we discuss the design considerations for creating new sediment habitats in the intertidal zone within new coastal infrastructure works. We focus on the sediment control structures required to satisfy the physiological and ecological requirements of seagrass and mangroves – two keystone intertidal species that are common candidates for restoration – and illustrate the concepts by discussing the case study of soft habitat creation within a major multi-commodity port.
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Gagnon K, Christie H, Didderen K, Fagerli CW, Govers LL, Gräfnings MLE, Heusinkveld JHT, Kaljurand K, Lengkeek W, Martin G, Meysick L, Pajusalu L, Rinde E, Heide T, Boström C. Incorporating facilitative interactions into small‐scale eelgrass restoration—challenges and opportunities. Restor Ecol 2021. [DOI: 10.1111/rec.13398] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Karine Gagnon
- Environmental and Marine Biology Åbo Akademi University Åbo Finland
| | | | | | | | - Laura L. Govers
- Conservation Ecology Group, Groningen Institute for Evolutionary Life Sciences (GELIFES) University of Groningen Groningen The Netherlands
- Department of Aquatic Ecology and Environmental Biology, Institute for Water and Wetland Research (IWWR) Radboud University Nijmegen The Netherlands
- Department of Coastal Systems Royal Netherlands Institute of Sea Research and Utrecht University Den Burg The Netherlands
| | - Max L. E. Gräfnings
- Environmental and Marine Biology Åbo Akademi University Åbo Finland
- Conservation Ecology Group, Groningen Institute for Evolutionary Life Sciences (GELIFES) University of Groningen Groningen The Netherlands
- Department of Aquatic Ecology and Environmental Biology, Institute for Water and Wetland Research (IWWR) Radboud University Nijmegen The Netherlands
| | | | - Kaire Kaljurand
- Estonian Marine Institute University of Tartu Tallinn Estonia
| | - Wouter Lengkeek
- Bureau Waardenburg Culemborg The Netherlands
- Department of Aquatic Ecology and Environmental Biology, Institute for Water and Wetland Research (IWWR) Radboud University Nijmegen The Netherlands
| | - Georg Martin
- Estonian Marine Institute University of Tartu Tallinn Estonia
| | - Lukas Meysick
- Environmental and Marine Biology Åbo Akademi University Åbo Finland
- Helmholtz Institute for Functional Marine Biodiversity at the University of Oldenburg (HIFMB) Oldenburg Germany
- Alfred‐Wegener‐Institute Helmholtz Centre for Polar and Marine Research Bremerhaven Germany
| | - Liina Pajusalu
- Estonian Marine Institute University of Tartu Tallinn Estonia
| | - Eli Rinde
- Norwegian Institute for Water Research Oslo Norway
| | - Tjisse Heide
- Conservation Ecology Group, Groningen Institute for Evolutionary Life Sciences (GELIFES) University of Groningen Groningen The Netherlands
- Department of Aquatic Ecology and Environmental Biology, Institute for Water and Wetland Research (IWWR) Radboud University Nijmegen The Netherlands
- Department of Coastal Systems Royal Netherlands Institute of Sea Research and Utrecht University Den Burg The Netherlands
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Gagnon K, Rinde E, Bengil EGT, Carugati L, Christianen MJA, Danovaro R, Gambi C, Govers LL, Kipson S, Meysick L, Pajusalu L, Tüney Kızılkaya İ, Koppel J, Heide T, Katwijk MM, Boström C. Facilitating foundation species: The potential for plant–bivalve interactions to improve habitat restoration success. J Appl Ecol 2020. [DOI: 10.1111/1365-2664.13605] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Karine Gagnon
- Environmental and Marine Biology Åbo Akademi University Turku Finland
| | - Eli Rinde
- Norwegian Institute for Water Research Oslo Norway
| | - Elizabeth G. T. Bengil
- Mediterranean Conservation Society Izmir Turkey
- Girne American UniversityMarine School Girne TRNC via Turkey
| | - Laura Carugati
- Department of Life and Environmental Sciences Polytechnic University of Marche Ancona Italy
| | - Marjolijn J. A. Christianen
- Aquatic Ecology and Water Quality Management Group Wageningen University Wageningen The Netherlands
- Department of Environmental Science Institute for Wetland and Water Research Radboud University Nijmegen Nijmegen The Netherlands
| | - Roberto Danovaro
- Department of Life and Environmental Sciences Polytechnic University of Marche Ancona Italy
- Stazione Zoologica Anton Dohrn Naples Italy
| | - Cristina Gambi
- Department of Life and Environmental Sciences Polytechnic University of Marche Ancona Italy
| | - Laura L. Govers
- Department of Environmental Science Institute for Wetland and Water Research Radboud University Nijmegen Nijmegen The Netherlands
- Groningen Institute for Evolutionary Life Sciences University of Groningen Groningen The Netherlands
| | - Silvija Kipson
- Faculty of Science Department of Biology University of Zagreb Zagreb Croatia
| | - Lukas Meysick
- Environmental and Marine Biology Åbo Akademi University Turku Finland
| | - Liina Pajusalu
- Estonian Marine Institute University of Tartu Tallinn Estonia
| | - İnci Tüney Kızılkaya
- Mediterranean Conservation Society Izmir Turkey
- Faculty of Science Ege University Izmir Turkey
| | - Johan Koppel
- Groningen Institute for Evolutionary Life Sciences University of Groningen Groningen The Netherlands
- Royal Netherlands Institute for Sea Research and Utrecht University Yerseke The Netherlands
| | - Tjisse Heide
- Department of Environmental Science Institute for Wetland and Water Research Radboud University Nijmegen Nijmegen The Netherlands
- Groningen Institute for Evolutionary Life Sciences University of Groningen Groningen The Netherlands
- Department of Coastal Systems Royal Netherlands Institute of Sea Research and Utrecht University Den Burg The Netherlands
| | - Marieke M. Katwijk
- Department of Environmental Science Institute for Wetland and Water Research Radboud University Nijmegen Nijmegen The Netherlands
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Abstract
Invertebrate diversity can be a key driver of ecosystem functioning, yet understanding what factors influence local biodiversity remains uncertain. In many marine and terrestrial systems, facilitation cascades where primary foundation and/or autogenic ecosystem engineering species promote the settlement and survival of a secondary foundation/engineering species have been shown to enhance local biodiversity and ecosystem functioning. We experimentally tested if a facilitation cascade occurs among eelgrass (Zostera marina), pen clams (Atrina rigida), and community diversity in temperate seagrass beds in North Carolina, U.S.A., and if this sequence of direct positive interactions created feedbacks that affected various metrics of seagrass ecosystem function and structure. Using a combination of surveys and transplant experiments, we found that pen clam density and survivorship was significantly greater in seagrass beds, indicating that eelgrass facilitates pen clams. Pen clams in turn enhanced local diversity and increased both the abundance and species richness of organisms (specifically, macroalgae and fouling invertebrate fauna)—the effect of which scaled with increasing clam density. However, we failed to detect an impact of pen clams on other seagrass functions and hypothesize that functioning may more likely be enhanced in scenarios where secondary foundation species specifically increase the diversity of key functional groups such as epiphyte grazers and/or when bivalves are infaunal rather than epifaunal. Our findings add to the growing amount of literature that demonstrates that secondary foundation species are important drivers of local biodiversity in marine ecosystems. Further experimentation is needed that directly examines (i) the role of functional versus overall diversity on seagrass functions and (ii) the relative importance of life-history strategy in determining when and where engineering bivalves increase biodiversity and/or functioning of seagrass beds.
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Oysters and the Ecosystem. ACTA ACUST UNITED AC 2017. [DOI: 10.1016/b978-0-12-803472-9.00010-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Sharma S, Goff J, Moody RM, McDonald A, Byron D, Heck KL, Powers SP, Ferraro C, Cebrian J. Effects of Shoreline Dynamics on Saltmarsh Vegetation. PLoS One 2016; 11:e0159814. [PMID: 27442515 PMCID: PMC4956348 DOI: 10.1371/journal.pone.0159814] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 07/09/2016] [Indexed: 11/19/2022] Open
Abstract
We evaluated the impact of shoreline dynamics on fringing vegetation density at mid- and low-marsh elevations at a high-energy site in the northern Gulf of Mexico. Particularly, we selected eight unprotected shoreline stretches (75 m each) at a historically eroding site and measured their inter-annual lateral movement rate using the DSAS method for three consecutive years. We observed high inter-annual variability of shoreline movement within the selected stretches. Specifically, shorelines retrograded (eroded) in year 1 and year 3, whereas, in year 2, shorelines advanced seaward. Despite shoreline advancement in year 2, an overall net erosion was recorded during the survey period. Additionally, vegetation density generally declined at both elevations during the survey period; however, probably due to their immediate proximity with lateral erosion agents (e.g., waves, currents), marsh grasses at low-elevation exhibited abrupt reduction in density, more so than grasses at mid elevation. Finally, contrary to our hypothesis, despite shoreline advancement, vegetation density did not increase correspondingly in year 2 probably due to a lag in response from biota. More studies in other coastal systems may advance our knowledge of marsh edge systems; however, we consider our results could be beneficial to resource managers in preparing protection plans for coastal wetlands against chronic stressors such as lateral erosion.
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Affiliation(s)
- Shailesh Sharma
- Department of Marine Sciences, University of South Alabama, Mobile, Alabama, United States of America
- Dauphin Island Sea Lab, Dauphin Island, Alabama, United States of America
- * E-mail:
| | - Joshua Goff
- Dauphin Island Sea Lab, Dauphin Island, Alabama, United States of America
| | - Ryan M. Moody
- Dauphin Island Sea Lab, Dauphin Island, Alabama, United States of America
| | - Ashley McDonald
- Department of Marine Sciences, University of South Alabama, Mobile, Alabama, United States of America
- Dauphin Island Sea Lab, Dauphin Island, Alabama, United States of America
| | - Dorothy Byron
- Dauphin Island Sea Lab, Dauphin Island, Alabama, United States of America
| | - Kenneth L. Heck
- Department of Marine Sciences, University of South Alabama, Mobile, Alabama, United States of America
- Dauphin Island Sea Lab, Dauphin Island, Alabama, United States of America
| | - Sean P. Powers
- Department of Marine Sciences, University of South Alabama, Mobile, Alabama, United States of America
- Dauphin Island Sea Lab, Dauphin Island, Alabama, United States of America
| | - Carl Ferraro
- State Lands Division Coastal Section, Alabama Department of Conservation and Natural Resources, Spanish Fort, Alabama, United States of America
| | - Just Cebrian
- Department of Marine Sciences, University of South Alabama, Mobile, Alabama, United States of America
- Dauphin Island Sea Lab, Dauphin Island, Alabama, United States of America
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