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Lange ID, Razak TB, Perry CT, Maulana PB, Prasetya ME, Irwan, Lamont TA. Coral restoration can drive rapid reef carbonate budget recovery. Curr Biol 2024; 34:1341-1348.e3. [PMID: 38460511 DOI: 10.1016/j.cub.2024.02.009] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 12/05/2023] [Accepted: 02/06/2024] [Indexed: 03/11/2024]
Abstract
Restoration is increasingly seen as a necessary tool to reverse ecological decline across terrestrial and marine ecosystems.1,2 Considering the unprecedented loss of coral cover and associated reef ecosystem services, active coral restoration is gaining traction in local management strategies and has recently seen major increases in scale. However, the extent to which coral restoration may restore key reef functions is poorly understood.3,4 Carbonate budgets, defined as the balance between calcium carbonate production and erosion, influence a reef's ability to provide important geo-ecological functions including structural complexity, reef framework production, and vertical accretion.5 Here we present the first assessment of reef carbonate budget trajectories at restoration sites. The study was conducted at one of the world's largest coral restoration programs, which transplants healthy coral fragments onto hexagonal metal frames to consolidate degraded rubble fields.6 Within 4 years, fast coral growth supports a rapid recovery of coral cover (from 17% ± 2% to 56% ± 4%), substrate rugosity (from 1.3 ± 0.1 to 1.7 ± 0.1) and carbonate production (from 7.2 ± 1.6 to 20.7 ± 2.2 kg m-2 yr-1). Four years after coral transplantation, net carbonate budgets have tripled and are indistinguishable from healthy control sites (19.1 ± 3.1 and 18.7 ± 2.2 kg m-2 yr-1, respectively). However, taxa-level contributions to carbonate production differ between restored and healthy reefs due to the preferential use of branching corals for transplantation. While longer observation times are necessary to observe any self-organization ability of restored reefs (natural recruitment, resilience to thermal stress), we demonstrate the potential of large-scale, well-managed coral restoration projects to recover important ecosystem functions within only 4 years.
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Affiliation(s)
- Ines D Lange
- Faculty of Environment, Science and Economy, University of Exeter, Exeter EX4 4RJ, UK.
| | - Tries B Razak
- Research Centre for Oceanography, National Research and Innovation Agency (BRIN), Jakarta Pusat 10340, Indonesia; School of Coral Reef Restoration (SCORES), Faculty of Fisheries and Marine Science, IPB University, Bogor 16680, Indonesia
| | - Chris T Perry
- Faculty of Environment, Science and Economy, University of Exeter, Exeter EX4 4RJ, UK
| | | | | | - Irwan
- Mars Sustainable Solutions, Makassar 90224, Indonesia
| | - Timothy Ac Lamont
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YW, UK
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2
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Elsmore K, Nickols KJ, Miller LP, Ford T, Denny MW, Gaylord B. Wave damping by giant kelp, Macrocystis pyrifera. Ann Bot 2024; 133:29-40. [PMID: 37463436 PMCID: PMC11087658 DOI: 10.1093/aob/mcad094] [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] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 07/13/2023] [Indexed: 07/20/2023]
Abstract
BACKGROUND AND AIMS The increased likelihood and severity of storm events has brought into focus the role of coastal ecosystems in provision of shoreline protection by attenuating wave energy. Canopy-forming kelps, including giant kelp (Macrocystis pyrifera), are thought to provide this ecosystem service, but supporting data are extremely limited. Previous in situ examinations relied mostly on comparisons between nominally similar sites with and without kelp. Given that other factors (especially seafloor bathymetry and topographic features) often differ across sites, efforts to isolate the effects of kelp on wave energy propagation confront challenges. In particular, it can be difficult to distinguish wave energy dissipation attributable to kelp from frictional processes at the seabed that often covary with the presence of kelp. Here, we use an ecological transition from no kelp to a full forest, at a single site with static bathymetry, to resolve unambiguously the capacity of giant kelp to damp waves. METHODS We measured waves within and outside rocky reef habitat, in both the absence and the presence of giant kelp, at Marguerite Reef, Palos Verdes, CA, USA. Nested within a broader kelp restoration project, this site transitioned from a bare state to one supporting a fully formed forest (density of 8 stipes m-2). We quantified, as a function of incident wave conditions, the decline in wave energy flux attributable to the presence of kelp, as waves propagated from outside and into reef habitat. KEY RESULTS The kelp forest damped wave energy detectably, but to a modest extent. Interactions with the seabed alone reduced wave energy flux, on average, by 12 ± 1.4 % over 180 m of travel. The kelp forest induced an additional 7 ± 1.2 % decrease. Kelp-associated declines in wave energy flux were slightly greater for waves of longer periods and smaller wave heights. CONCLUSIONS Macrocystis pyrifera forests have a limited, albeit measurable, capacity to enhance shoreline protection from nearshore waves. Expectations that giant kelp forests, whether extant or enhanced through restoration, have substantial impacts on wave-induced coastal erosion might require re-evaluation.
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Affiliation(s)
- Kristen Elsmore
- Bodega Marine Laboratory, University of California at Davis, 2099 Westshore Road, Bodega Bay, CA 94923, USA
| | - Kerry J Nickols
- Department of Biology, California State University, Northridge, 18111 Nordhoff Street, Northridge, CA 91330, USA
| | - Luke P Miller
- Department of Biology, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182, USA
| | - Tom Ford
- Coastal Research Institute, Loyola Marymount University, 1 Loyola Marymount Drive, Los Angeles, CA 90045, USA
| | - Mark W Denny
- Hopkins Marine Station, Stanford University, 120 Ocean View Boulevard, Pacific Grove, CA 93950, USA
| | - Brian Gaylord
- Bodega Marine Laboratory, University of California at Davis, 2099 Westshore Road, Bodega Bay, CA 94923, USA
- Department of Evolution and Ecology, University of California at Davis, 1 Shields Avenue, Davis, CA 95616, USA
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3
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Solan M, Spencer T, Paterson DM, Unsworth CA, Christie EK, Blight AJ, Brown J, Brooks H, Lichtman ID, Wei X, Li X, Thorne P, Leyland J, Godbold JA, Thompson C, Williams ME, Plater A, Moller I, Amoudry LO. Biological-physical interactions are fundamental to understanding and managing coastal dynamics. R Soc open sci 2023; 10:230155. [PMID: 37448479 PMCID: PMC10336386 DOI: 10.1098/rsos.230155] [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: 02/09/2023] [Accepted: 06/21/2023] [Indexed: 07/15/2023]
Abstract
There is an urgent need to address coastal dynamics as a fundamental interaction between physical and biological processes, particularly when trying to predict future biological-physical linkages under anticipated changes in environmental forcing. More integrated modelling, support for observational networks and the use of management interventions as controlled experimental exercises should now be vigorously pursued.
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Affiliation(s)
- Martin Solan
- School of Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Waterfront Campus, European Way, Southampton SO14 3ZH, UK
| | - Tom Spencer
- Cambridge Coastal Research Unit, Department of Geography, University of Cambridge, Downing Place, Cambridge CB2 3EN, UK
| | - David M Paterson
- Scottish Oceans Institute, School of Biology, Sediment Ecology Research Group, University of St Andrews, St Andrews, Fife KY16 8LB, UK
| | - Christopher A Unsworth
- Marine Physics and Ocean Climate, National Oceanography Centre, Joseph Proudman Building, 6 Brownlow Street, Liverpool L3 5DA, UK
| | - Elizabeth K Christie
- Cambridge Coastal Research Unit, Department of Geography, University of Cambridge, Downing Place, Cambridge CB2 3EN, UK
| | - Andrew J Blight
- Scottish Oceans Institute, School of Biology, Sediment Ecology Research Group, University of St Andrews, St Andrews, Fife KY16 8LB, UK
| | - Jenny Brown
- Marine Physics and Ocean Climate, National Oceanography Centre, Joseph Proudman Building, 6 Brownlow Street, Liverpool L3 5DA, UK
| | - Helen Brooks
- Cambridge Coastal Research Unit, Department of Geography, University of Cambridge, Downing Place, Cambridge CB2 3EN, UK
- Environment Agency, Tyneside House, Skinnerburn Road, Newcastle Business Park, Newcastle upon Tyne NE4 7AR, UK
| | - I Dougal Lichtman
- Marine Physics and Ocean Climate, National Oceanography Centre, Joseph Proudman Building, 6 Brownlow Street, Liverpool L3 5DA, UK
| | - Xiaoyan Wei
- Marine Physics and Ocean Climate, National Oceanography Centre, Joseph Proudman Building, 6 Brownlow Street, Liverpool L3 5DA, UK
| | - Xiaorong Li
- Department of Geography and Planning, School of Environmental Sciences, University of Liverpool, Liverpool L69 7ZT, UK
- Energy and Environment Research Group, College of Engineering, Swansea University, Swansea SA2 8PP, UK
| | - Pete Thorne
- Marine Physics and Ocean Climate, National Oceanography Centre, Joseph Proudman Building, 6 Brownlow Street, Liverpool L3 5DA, UK
| | - Julian Leyland
- School of Geography and Environmental Science, University of Southampton, Highfield, Southampton SO17 1BJ, UK
| | - Jasmin A Godbold
- School of Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Waterfront Campus, European Way, Southampton SO14 3ZH, UK
| | - Charlie Thompson
- School of Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Waterfront Campus, European Way, Southampton SO14 3ZH, UK
- Channel Coastal Observatory, National Oceanography Centre, University of Southampton, Waterfront Campus, European Way, Southampton SO14 3ZH, UK
| | - Megan E Williams
- Marine Physics and Ocean Climate, National Oceanography Centre, Joseph Proudman Building, 6 Brownlow Street, Liverpool L3 5DA, UK
- Departamento de Ingeniería Hidráulica y Ambiental, Facultad de Ingeniería, Pontificia Universidad Católica de Chile, Santiago, Chile
- Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Andrew Plater
- Department of Geography and Planning, School of Environmental Sciences, University of Liverpool, Liverpool L69 7ZT, UK
| | - Iris Moller
- Cambridge Coastal Research Unit, Department of Geography, University of Cambridge, Downing Place, Cambridge CB2 3EN, UK
- Department of Geography, Trinity College Dublin, Museum Building, Dublin 2, Ireland
| | - Laurent O Amoudry
- Marine Physics and Ocean Climate, National Oceanography Centre, Joseph Proudman Building, 6 Brownlow Street, Liverpool L3 5DA, UK
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4
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Summers S, Pek YS, Vinod DP, McDougald D, Todd PA, Birch WR, Rice SA. Bacterial biofilm colonization and succession in tropical marine waters are similar across different types of stone materials used in seawall construction. Front Microbiol 2022; 13:928877. [PMID: 35958146 PMCID: PMC9358718 DOI: 10.3389/fmicb.2022.928877] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 07/07/2022] [Indexed: 11/13/2022] Open
Abstract
Seawalls are important in protecting coastlines from currents, erosion, sea-level rise, and flooding. They are, however, associated with reduced biodiversity, due to their steep orientation, lack of microhabitats, and the materials used in their construction. Hence, there is considerable interest in modifying seawalls to enhance the settlement and diversity of marine organisms, as microbial biofilms play a critical role facilitating algal and invertebrate colonization. We assessed how different stone materials, ranging from aluminosilicates to limestone and concrete, affect biofilm formation. Metagenomic assessment of marine microbial communities indicated no significant impact of material on microbial diversity, irrespective of the diverse surface chemistry and topography. Based on KEGG pathway analysis, surface properties appeared to influence the community composition and function during the initial stages of biofilm development, but this effect disappeared by Day 31. We conclude that marine biofilms converged over time to a generic marine biofilm, rather than the underlying stone substrata type playing a significant role in driving community composition.
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Affiliation(s)
- Stephen Summers
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
| | - Y. Shona Pek
- Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Deepthi P. Vinod
- School of Bioscience and Technology, Vellore Institute of Technology, Vellore, India
| | - Diane McDougald
- Australian Institute for Microbiology and Infection, The University of Technology Sydney, Sydney, NSW, Australia
| | - Peter A. Todd
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - William R. Birch
- Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Scott A. Rice
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
- Agriculture and Food, Microbiomes for One Systems Health, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Canberra, ACT, Australia
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5
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Wellman EH, Baillie CJ, Puckett BJ, Donaher SE, Trackenberg SN, Gittman RK. Reef design and site hydrodynamics mediate oyster restoration and marsh stabilization outcomes. Ecol Appl 2022; 32:e2506. [PMID: 34870355 DOI: 10.1002/eap.2506] [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: 02/08/2021] [Revised: 06/17/2021] [Accepted: 07/09/2021] [Indexed: 06/13/2023]
Abstract
The detrimental ecological impacts of engineered shoreline protection methods (e.g., seawalls) and the need to protect the coastal zone have prompted calls for greater use of natural and nature-based infrastructure (NNBI). To balance competing needs of structural stability and ecological functioning, managers require assessments of NNBI designs and materials for differing environmental settings (e.g., among wave-energy regimes). To examine the effects of setting and oyster-based NNBI design on the provision of shoreline protection, we constructed reefs from two substrates: a novel, biodegradable material (Oyster Catcher, OC) and traditional oyster shell bags (SB) on low- and high-energy eroding salt marsh shorelines, designated based on fetch and boat wake exposure. Both reef types buffered marsh elevation change on the high-energy shoreline relative to unaltered controls, but only SB reefs were able to do so on the low-energy shoreline. Additionally, both shorelines experienced high ambient rates of retreat and declines in marsh vegetation shoot density. Although constructed reefs did not mitigate marsh retreat on the low-energy shoreline, novel OC reefs significantly reduced retreat relative to SB reefs and control sites (no reefs) on the high-energy shoreline. Those SB reefs were severely damaged by storm events, increasing their areal footprints at the expense of vertical relief. Conversely, OC reefs on both shorelines exhibited steady oyster recruitment and growth and hosted higher densities of larger oysters. To successfully provide shoreline stabilization benefits, oyster-based NNBI must be structurally stable and able to promote sustained oyster recruitment and growth. Our results indicate that deliberate decisions regarding NNBI substrate, siting, and configuration can produce resilient reefs, which reduce rates of erosion and, in some cases, enhance vertical accretion along salt marsh edges. The growth trajectory, structural stability, and co-benefit provisioning of OC reefs demonstrate the potential of alternative restoration substrates to provide valuable oyster habitat along threatened marsh shorelines.
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Affiliation(s)
- Emory H Wellman
- Department of Biology, East Carolina University, Greenville, North Carolina, USA
| | | | - Brandon J Puckett
- North Carolina Coastal Reserve and National Estuarine Research Reserve, Beaufort, North Carolina, USA
| | - Sarah E Donaher
- Department of Environmental Engineering and Earth Sciences, Clemson University, Anderson, South Carolina, USA
| | - Stacy N Trackenberg
- Department of Biology, East Carolina University, Greenville, North Carolina, USA
| | - Rachel K Gittman
- Department of Biology, East Carolina University, Greenville, North Carolina, USA
- Coastal Studies Institute, East Carolina University, Wanchese, North Carolina, USA
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6
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Pennings SC, Glazner RM, Hughes ZJ, Kominoski JS, Armitage AR. Effects of mangrove cover on coastal erosion during a hurricane in Texas, USA. Ecology 2021; 102:e03309. [PMID: 33576002 DOI: 10.1002/ecy.3309] [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] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 11/24/2020] [Accepted: 02/05/2021] [Indexed: 11/07/2022]
Abstract
We tested the hypothesis that mangroves provide better coastal protection than salt marsh vegetation using 10 1,008-m2 plots in which we manipulated mangrove cover from 0 to 100%. Hurricane Harvey passed over the plots in 2017. Data from erosion stakes indicated up to 26 cm of vertical and 970 cm of horizontal erosion over 70 months in the plot with 0% mangrove cover, but relatively little erosion in other plots. The hurricane did not increase erosion, and erosion decreased after the hurricane passed. Data from drone images indicated 196 m2 of erosion in the 0% mangrove plot, relatively little erosion in other plots, and little ongoing erosion after the hurricane. Transects through the plots indicated that the levee (near the front of the plot) and the bank (the front edge of the plot) retreated up to 9 m as a continuous function of decreasing mangrove cover. Soil strength was greater in areas vegetated with mangroves than in areas vegetated by marsh plants, or nonvegetated areas, and increased as a function of plot-level mangrove cover. Mangroves prevented erosion better than marsh plants did, but this service was nonlinear, with low mangrove cover providing most of the benefits.
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Affiliation(s)
- Steven C Pennings
- Department of Biology and Biochemistry, University of Houston, Houston, Texas, 77204, USA
| | - Rachael M Glazner
- Department of Marine Biology, Texas A&M University at Galveston, Galveston, Texas, 77553, USA
| | - Zoe J Hughes
- Department of Biology and Biochemistry, University of Houston, Houston, Texas, 77204, USA
- Department of Earth Sciences, Boston University, Boston, Massachusetts, 02215, USA
| | - John S Kominoski
- Department of Biological Sciences, Florida International University, Miami, Florida, 33199, USA
| | - Anna R Armitage
- Department of Marine Biology, Texas A&M University at Galveston, Galveston, Texas, 77553, USA
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7
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Abstract
Restoration efforts have been escalating worldwide in response to widespread habitat degradation. However, coastal restoration attempts notoriously vary in their ability to establish resilient, high-functioning ecosystems. Conventional restoration attempts disperse transplants in competition-minimizing arrays, yet recent studies suggest that clumping transplants to maximize facilitative interactions may improve restoration success. Here, we modify the stress gradient hypothesis to generate predictions about where each restoration design will perform best across environmental stress gradients. We then test this conceptual model with field experiments manipulating transplant density and configuration across dune elevations and latitudes. In hurricane-damaged Georgia (USA) dunes, grass transplanted in competition-minimizing (low-density, dispersed) arrays exhibited the highest growth, resilience to disturbance and dune formation in low-stress conditions. In contrast, transplants survived best in facilitation-maximizing (high-density, clumped) arrays in high-stress conditions, but these benefits did not translate to higher transplant growth or resilience. In a parallel experiment in Massachusetts where dune grasses experience frequent saltwater inundation, fewer transplants survived, suggesting that there are thresholds above which intraspecific facilitation cannot overcome local stressors. These results suggest that ecological theory can be used to guide restoration strategies based on local stress regimes, maximizing potential restoration success and return-on-investment of future efforts.
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Affiliation(s)
- Hallie S Fischman
- Department of Ecology and Evolutionary Biology, Brown University, Providence, RI 02912, USA
| | - Sinead M Crotty
- Department of Environmental Engineering Sciences, Engineering School for Sustainable Infrastructure and the Environment, University of Florida, Gainesville, FL 32611, USA
| | - Christine Angelini
- Department of Environmental Engineering Sciences, Engineering School for Sustainable Infrastructure and the Environment, University of Florida, Gainesville, FL 32611, USA
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8
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Wanger TC, Ainun N, Brook BW, Friess DA, Oh RRY, Rusdin A, Smithers S, Tjoa A. Ecosystem-Based Tsunami Mitigation for Tropical Biodiversity Hotspots. Trends Ecol Evol 2019; 35:96-100. [PMID: 31837810 DOI: 10.1016/j.tree.2019.10.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 10/13/2019] [Accepted: 10/15/2019] [Indexed: 11/28/2022]
Abstract
Inclusion of ecosystem-based approaches in the governmental masterplan for tsunami mitigation in Palu, Indonesia may make the city a rare case study for ecological disaster risk reduction in tropical biodiversity hotspots. Such case studies are a key pillar of the United Nations (UN) Sendai Framework to protect coastal societies globally.
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Affiliation(s)
- Thomas Cherico Wanger
- Agroecology and Centre of Biodiversity and Sustainable Land Use, University of Göttingen, Germany; Sustainability, Agriculture and Technology Laboratory, School of Engineering, Westlake University, China.
| | - Nur Ainun
- Fakultas Pertanian, Tadulako University, Palu, Indonesia
| | - Barry W Brook
- School of Natural Sciences, University of Tasmania, Australia
| | - Daniel A Friess
- Department of Geography, National University of Singapore, Singapore
| | - Rachel R Y Oh
- School of Biological Sciences, University of Queensland, Australia
| | - Andi Rusdin
- Faculty of Engineering, Tadulako University, Palu, Indonesia
| | - Scott Smithers
- College of Science and Engineering, James Cook University, Australia
| | - Aiyen Tjoa
- Fakultas Pertanian, Tadulako University, Palu, Indonesia
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9
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Morris RL, Konlechner TM, Ghisalberti M, Swearer SE. From grey to green: Efficacy of eco-engineering solutions for nature-based coastal defence. Glob Chang Biol 2018; 24:1827-1842. [PMID: 29350842 DOI: 10.1111/gcb.14063] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [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: 10/04/2017] [Accepted: 12/18/2017] [Indexed: 05/10/2023]
Abstract
Climate change is increasing the threat of erosion and flooding along coastlines globally. Engineering solutions (e.g. seawalls and breakwaters) in response to protecting coastal communities and associated infrastructure are increasingly becoming economically and ecologically unsustainable. This has led to recommendations to create or restore natural habitats, such as sand dunes, saltmarsh, mangroves, seagrass and kelp beds, and coral and shellfish reefs, to provide coastal protection in place of (or to complement) artificial structures. Coastal managers are frequently faced with the problem of an eroding coastline, which requires a decision on what mitigation options are most appropriate to implement. A barrier to uptake of nature-based coastal defence is stringent evaluation of the effectiveness in comparison to artificial protection structures. Here, we assess the current evidence for the efficacy of nature-based vs. artificial coastal protection and discuss future research needs. Future projects should evaluate habitats created or restored for coastal defence for cost-effectiveness in comparison to an artificial structure under the same environmental conditions. Cost-benefit analyses should take into consideration all ecosystem services provided by nature-based or artificial structures in addition to coastal protection. Interdisciplinary research among scientists, coastal managers and engineers is required to facilitate the experimental trials needed to test the value of these shoreline protection schemes, in order to support their use as alternatives to artificial structures. This research needs to happen now as our rapidly changing climate requires new and innovative solutions to reduce the vulnerability of coastal communities to an increasingly uncertain future.
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Affiliation(s)
- Rebecca L Morris
- National Centre for Coasts and Climate, School of BioSciences, The University of Melbourne, Melbourne, Vic., Australia
| | - Teresa M Konlechner
- National Centre for Coasts and Climate, School of Geography, The University of Melbourne, Melbourne, Vic., Australia
| | - Marco Ghisalberti
- Department of Infrastructure Engineering, The University of Melbourne, Melbourne, Vic., Australia
| | - Stephen E Swearer
- National Centre for Coasts and Climate, School of BioSciences, The University of Melbourne, Melbourne, Vic., Australia
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10
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Kelleway JJ, Cavanaugh K, Rogers K, Feller IC, Ens E, Doughty C, Saintilan N. Review of the ecosystem service implications of mangrove encroachment into salt marshes. Glob Chang Biol 2017; 23:3967-3983. [PMID: 28544444 DOI: 10.1111/gcb.13727] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [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: 12/21/2016] [Accepted: 02/21/2017] [Indexed: 06/07/2023]
Abstract
Salt marsh and mangrove have been recognized as being among the most valuable ecosystem types globally in terms of their supply of ecosystem services and support for human livelihoods. These coastal ecosystems are also susceptible to the impacts of climate change and rising sea levels, with evidence of global shifts in the distribution of mangroves, including encroachment into salt marshes. The encroachment of woody mangrove shrubs and trees into herbaceous salt marshes may represent a substantial change in ecosystem structure, although resulting impacts on ecosystem functions and service provisions are largely unknown. In this review, we assess changes in ecosystem services associated with mangrove encroachment. While there is quantitative evidence to suggest that mangrove encroachment may enhance carbon storage and the capacity of a wetland to increase surface elevation in response to sea-level rise, for most services there has been no direct assessment of encroachment impact. On the basis of current understanding of ecosystem structure and function, we theorize that mangrove encroachment may increase nutrient storage and improve storm protection, but cause declines in habitat availability for fauna requiring open vegetation structure (such as migratory birds and foraging bats) as well as the recreational and cultural activities associated with this fauna (e.g., birdwatching and/or hunting). Changes to provisional services such as fisheries productivity and cultural services are likely to be site specific and dependent on the species involved. We discuss the need for explicit experimental testing of the effects of encroachment on ecosystem services in order to address key knowledge gaps, and present an overview of the options available to coastal resource managers during a time of environmental change.
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Affiliation(s)
- Jeffrey J Kelleway
- Department of Environmental Sciences, Macquarie University, Sydney, NSW, Australia
| | - Kyle Cavanaugh
- Department of Geography, University of California, Los Angeles, CA, USA
| | - Kerrylee Rogers
- School of Earth and Environmental Science, University of Wollongong, Wollongong, NSW, Australia
| | - Ilka C Feller
- Smithsonian Environmental Research Center, Edgewater, MD, USA
| | - Emilie Ens
- Department of Environmental Sciences, Macquarie University, Sydney, NSW, Australia
| | - Cheryl Doughty
- Department of Geography, University of California, Los Angeles, CA, USA
| | - Neil Saintilan
- Department of Environmental Sciences, Macquarie University, Sydney, NSW, Australia
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11
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Müller WW, Saathoff F. Geosynthetics in geoenvironmental engineering. Sci Technol Adv Mater 2015; 16:034605. [PMID: 27877792 PMCID: PMC5099829 DOI: 10.1088/1468-6996/16/3/034605] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2014] [Revised: 03/12/2015] [Accepted: 03/16/2015] [Indexed: 06/06/2023]
Abstract
Geosynthetics are planar polymeric products, which are used in connection with soil, rock or other soil-like materials to fulfill various functions in geoenvironmental engineering. Geosynthetics are of ever-growing importance in the construction industry. Sealing of waste storage facilities to safely prevent the emission of wastewater, landfill gas and contaminated dust as well as the diffusion of pollutants into the environment and coastal protection against storms and floods and reconstruction after natural disaster are important fields of application. We will give an overview of the various geosynthetic products. Two examples of the material problems related to geosynthetics are discussed in detail: the effect of creep on the long-term performance of geocomposite drains and the numerical simulation of the interaction of soil with geogrids. Both issues are of importance for the use of these products in landfill capping systems. The various functions, which geosynthetics may fulfill in the protection of coastal lines, are illustrated by case studies. The geosynthetic market is evaluated and economical and environmental benefits, as well as environmental side effects related to the use of geosynthetics, are discussed.
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Affiliation(s)
- Werner W Müller
- BAM Federal Institute for Materials Research and Testing, Unter den Eichen 87, D-12205 Berlin, Germany
| | - Fokke Saathoff
- Chair of Geotechnics and Coastal Engineering, Universität Rostock, Justus-von-Liebig-Weg 6, LAGII, D-18059 Rostock, Germany
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Zarnetske PL, Ruggiero P, Seabloom EW, Hacker SD. Coastal foredune evolution: the relative influence of vegetation and sand supply in the US Pacific Northwest. J R Soc Interface 2015; 12:rsif.2015.0017. [PMID: 25833242 DOI: 10.1098/rsif.2015.0017] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Biophysical feedbacks between vegetation and sediment are important for forming and modifying landscape features and their ecosystem services. These feedbacks are especially important where landscape features differ in their provision of ecosystem services. For example, the shape of coastal foredunes, a product of both physical and biological forces, determines their ability to protect communities from rising seas and changing patterns of storminess. Here we assessed how sand supply and changes in vegetation over interannual (3 year) and decadal (21 year) scales influenced foredune shape along 100 km of coastline in the US Pacific Northwest. Across 21 years, vegetation switched from one congeneric non-native beachgrass to another (Ammophila arenaria to A. breviligulata) while sand supply rates were positive. At interannual timescales, sand supply rates explained the majority of change in foredune height (64-69%) and width (56-80%). However, at decadal scales, change in vegetation explained the majority of the change in foredune width (62-68%), whereas sand supply rates explained most of the change in foredune height (88-90%). In areas with lower shoreline change rates (±2 m yr(-1)), the change in vegetation explained the majority of decadal changes in foredune width (56-57%) and height (59-76%). Foredune shape directly impacts coastal protection, thus our findings are pertinent to coastal management given pressures of development and climate change.
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Affiliation(s)
- Phoebe L Zarnetske
- Department of Integrative Biology, Oregon State University, 3029 Cordley Hall, Corvallis, OR 97331, USA
| | - Peter Ruggiero
- College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, 104 CEOAS Administration Building, Corvallis, OR 97331, USA
| | - Eric W Seabloom
- Department of Ecology, Evolution, and Behavior, University of Minnesota, 100 Ecology Building, 1987 Upper Buford Circle, St Paul, MN 55108, USA
| | - Sally D Hacker
- Department of Integrative Biology, Oregon State University, 3029 Cordley Hall, Corvallis, OR 97331, USA
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