Oysters' Integration on Submerged Breakwaters Offers New Adaptive Shoreline Protection in Low‐Energy Environments in the Face of Sea Level Rise

Journal of Geophysical Research Earth Surface, Journal Year: 2023, Volume and Issue: 128(11)

Published: Oct. 28, 2023

Abstract Sea level rise (SLR) and increasing storm frequency threaten coastal environments. Engineering solutions such as breakwaters will become ineffective for wave attenuation erosion control due to SLR. As a natural alternative, oysters create three‐dimensional, complex reef structures that attenuate energy increase sedimentation rates. If coupled with breakwaters, may maintain breakwaters' efficiency over time they are expected grow Here, we measured bathymetric changes 3 years (via GPS) dampening four‐made intertidal within small cove of the Choptank River (MD, USA). Then, modeled coupling gray through Delft3D‐SWAN evaluate performances hybrid on protection, under future scenarios SLR climate change. Modeling hydrodynamic results showed gradual reduction in However, when were included modeling, 100 was 75% 60% greater than at high low tides, respectively. Morphodynamic net export sediment from coast Oyster addition also provided shoreline protection retention compared use alone, thanks oysters' capability The between represent valuable effective methodology protect our changing rising sea, where optimal conditions oyster survivability occur maintained time.

Language: Английский

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Deltaic marsh accretion under episodic sediment supply controlled by river regulations and storms: Implications for coastal wetlands restoration in the Yellow River Delta

Journal of Hydrology, Journal Year: 2024, Volume and Issue: 635, P. 131221 - 131221

Published: April 21, 2024

Language: Английский

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Storm sediment contribution to salt marsh accretion and expansion

Geomorphology, Journal Year: 2023, Volume and Issue: 430, P. 108670 - 108670

Published: March 23, 2023

Salt marshes are ecosystems with significant economic and environmental value. However, the accelerating rate of sea-level rise is a threat to these ecosystems. Storms significantly contribute sediment budget salt marshes, playing critical role in marsh survival rise. There are, however, uncertainties on extent which storms sediments different areas platforms (e.g., outer vs interior) sources that draw offshore nearshore). This study uses field analyses from an eight-month campaign Ribble Estuary, North-West England, understand storms' influence supply whether can deliver new material onto platform would otherwise not be sourced fair-weather conditions. Field data traps indicate storm activity caused increase inorganic whole platform, especially benefitting interior. Geochemistry particle size distribution analysis majority supplied during stormy periods was generated by erosion resuspension mudflat tidal creek sediments, while only minimal contribution given transported outside intertidal system. suggests that, long term, will promote vertical accretion but might simultaneously reduce overall larger-scale availability implications for lateral retreat.

Language: Английский

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Storm Impacts on Mineral Mass Accumulation Rates of Coastal Marshes

Journal of Geophysical Research Earth Surface, Journal Year: 2024, Volume and Issue: 129(3)

Published: Feb. 26, 2024

Abstract Coastal marsh survival may be compromised by sea‐level rise, limited sediment supply, and subsidence. Storms represent a fundamental forcing for accumulation in starving marshes because they resuspend bottom material channels tidal flats transport it to the surface. However, is unrealistic simulate at high resolution all storms that occurred past decades obtain reliable rates. Similarly, difficult cover possible combinations of water levels wind conditions fictional scenarios. Thus, we developed new method derives long‐term deposition rates from short‐term generated finite number storms. Twelve with different intensity frequency were selected Terrebonne Bay, Louisiana, USA simulated 2D Delft3D‐FLOW model coupled Simulating Waves Nearshore (SWAN) module. Storm impact was analyzed terms geomorphic work, namely product frequency. To derive inorganic mass rates, generates every combination 12 chosen uses linear fit modeled measured The best (highest R 2 ) used map Results show storm 1.7 ± 1.6 years return period provides largest suggesting most impactful are those balance Model results higher facing open areas where waves can develop sediments. This has advantage considering only few real scenarios applied any marsh‐bay system.

Language: Английский

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Vertical accretion trends project doughnut-like fragmentation of saltmarshes

Communications Earth & Environment, Journal Year: 2024, Volume and Issue: 5(1)

Published: Feb. 9, 2024

Abstract Coastal saltmarshes keep pace with sea-level rise through in-situ production of organic material and incorporation allochthonous inorganic sediment. Here we report rates vertical accretion 16 new sediment cores collected proximal to platform edges within located behind four barrier islands along the southeast United States coast. All but two these exceed contemporaneous rate relative rise, often by a factor 1.5 or more. Comparison 80 additional measurements compiled across Georgia Bight reveals that marshes situated closer inlets large bays generally accrete faster than those adjacent small creeks interiors. These results demonstrate spatial dichotomy in resilience backbarrier saltmarshes: marsh interiors are near tipping point, mineral fluxes allow enhanced local well-exposed platform-edge marshes. Together, this suggests trending towards rapid, doughnut-like fragmentation.

Language: Английский

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Geomorphological changes and sediment carbon accumulation at the bare mudflat-saltmarsh interface: The role of typhoons

Geomorphology, Journal Year: 2024, Volume and Issue: 454, P. 109151 - 109151

Published: March 12, 2024

Language: Английский

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Deep Learning of High-Resolution Unmanned Aerial Vehicle Imagery for Classifying Halophyte Species: A Comparative Study for Small Patches and Mixed Vegetation

Remote Sensing, Journal Year: 2023, Volume and Issue: 15(11), P. 2723 - 2723

Published: May 24, 2023

Recent advances in deep learning (DL) and unmanned aerial vehicle (UAV) technologies have made it possible to monitor salt marshes more efficiently precisely. However, studies rarely compared the classification performance of DL with pixel-based method for coastal wetland monitoring using UAV data. In particular, many been conducted at landscape level; however, little is known about species discrimination very small patches mixed vegetation. We constructed a dataset based on UAV-RGB data methods five scenarios (combinations annotation type patch size) marsh Maximum likelihood, method, showed lowest overall accuracy 73%, whereas U-Net achieved over 90% all scenarios. As expected, comparison methods, approach most accurate results. Unexpectedly, there was no significant difference between two types labeling sizes this study. when comparing results detail, we confirmed that polygon-type effective mixed-vegetation than bounding-box type. Moreover, smaller size detecting vegetation patches. Our suggest combination can facilitate mapping local scale.

Language: Английский

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Improvement of the sediment flux estimation in the Yangtze River Estuary with a GOCI data adjusted numerical model

Ocean Modelling, Journal Year: 2023, Volume and Issue: 186, P. 102284 - 102284

Published: Oct. 21, 2023

Language: Английский

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Impacts of Climate Change on Coastal Hydrodynamics Around a Headland and Potential Headland Sediment Bypassing

Geophysical Research Letters, Journal Year: 2024, Volume and Issue: 51(4)

Published: Feb. 10, 2024

Abstract Shorelines face growing threats due to climate change and diminishing sand supply. Coastal headlands, common rocky features along coastlines, are crucial in shaping hydrodynamics sediment transport. Yet, the influence of future conditions, including sea‐level rise (SLR) intensified storm energy on complex shorelines with headlands has remained relatively unexplored. In this study, we model changes headland bypassing under different SLR higher wave scenarios. Our findings reveal formation circulation cells both sides a headland, where converges around zone. Future conditions result larger waves beach. However, enhances nearshore currents through landward shifting cells, while intensify offshore flow seaward movement cells. This effect, turn, increases potential for bypassing.

Language: Английский

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Effects of Seasonal Variations in Seagrass Density and Storms on Sediment Retention and Connectivity Between Subtidal Flats and Intertidal Marsh

Journal of Geophysical Research Biogeosciences, Journal Year: 2024, Volume and Issue: 129(4)

Published: April 1, 2024

Abstract Both submerged aquatic vegetation and salt marsh are important coastal ecosystems known for their effectiveness in sediment trapping carbon burial. However, proximity can lead to competition limited resources, potentially compromising capacity facilitate sufficient deposition withstand sea‐level rise. Here we applied the Delft3D flow transport model a shallow bay assess how seasonal variations seagrass density storms modulate retention connectivity between subtidal flats intertidal marsh. Results show that meadows acted as temporary storage fine altered timing of an adjacent through growth cycles. When occupied flats, flux was controlled by variations, with peak fluxes during winter senescence. In contrast, wave‐induced resuspension on major contributor input simulation no seagrass, storm‐driven summer/autumn. Overall, significantly increased annual accumulation vegetated tenfold, while reducing edge erosion 20%. Seagrass were both able maintain rate comparable rapid rise at study site despite absence terrestrial sources. Our findings highlight strong control has vertical horizontal dynamics tidal flat‐marsh systems provide insights inform wetland restoration management strategies similar systems.

Language: Английский

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