Shoreline Stabilization Research Articles

Mapping the Intertidal Microphytobenthos Gross Primary Production Part I: Coupling Multispectral Remote Sensing and Physical Modeling

The gross primary production (GPP) of intertidal mudflat microphytobenthos supports important ecosystem services such as shoreline stabilization and food production, and it contributes to blue carbon. However, monitoring microphytobenthos GPP over a long-term and large spatial scale is rendered difficult by its high temporal and spatial variability. To overcome this issue, we developed an algorithm to map microphytobenthos GPP in which the following are coupled: (i) NDVI maps derived from high spatial resolution satellite images (SPOT6 or Pleiades), estimating the horizontal distribution of the microphytobenthos biomass; (ii) emersion time, photosynthetically active radiation (PAR), and mud surface temperature simulated from the physical model MARS-3D; (iii) photophysiological parameters retrieved from Production-irradiance (P-E) curves, obtained under controlled conditions of PAR and temperature, using benthic chambers, and expressing the production rate into mg C h −1 m −2 ndvi −1. The productivity was directly calibrated to NDVI to be consistent with remote-sensing measurements of microphytobenthos biomass and was spatially upscaled using satellite-derived NDVI maps acquired at different seasons. The remotely sensed microphytobenthos GPP reasonably compared with in situ GPP measurements. It was highest in March with a daily production reaching 50.2 mg C m −2 d −1 , and lowest in July with a daily production of 22.3 mg C m −2 d −1. Our remote sensing algorithm is a new step in the perspective of mapping microphytobenthos GPP over large mudflats to estimate its actual contribution to ecosystem functions, including blue carbon, from local and global scales.

A holistic approach to evaluating dune cores

As population density increases in coastal counties, shoreline stabilization efforts continue to gain momentum to protect infrastructure. Although protection techniques vary from ‘soft’ to ‘hard’ engineering, this paper focuses on a ‘hybrid’ technique utilizing geotubes as artificial dune cores. Previous literature presents conflicting results on the efficacy and potential impacts of dune cores on a beach-dune system. Here we evaluate and quantify the geomorphic impacts following dune core installation and investigate their economic feasibility. This was completed by comparing five case studies: Sea Isle City, NJ; Bolivar Peninsula, TX; Grand Isle, LA; Santa Rosa Beach, FL; and Nantucket Island, MA. An economic assessment was completed to compare dune core installation costs and repairs to alternative shoreline hardening methods. LiDAR data were used to compare dune slope, beach width, and beach volume between digital transects adjacent to and in front of the dune core installations. Digital elevation models (DEMs) were generated to provide a holistic view of geomorphic change and to assess whether erosion occurred landward of the dune core. Results indicate that dune cores are an economically feasible option compared to alternative methods. Limitations include UV exposure, wave influence, and heavy winds. Morphologically, beach width was 29.1% wider in adjacent transects and dune slope was 39.1% steeper in front of the dune core. Beach volume was lower by an overall average of 23.4%. The findings from this study suggest that dune cores are a ‘hard’ or ‘grey’ protection method.

Dredging the sand commons: the economic and geophysical drivers of beach nourishment

Beaches are natural capital stocks that provide value through localized storm protection, recreational amenities, and ecosystem services at regional and global scales. In response to increased storm risks and sea-level rise, coastal communities invest in shoreline stabilization by rebuilding eroding sections of the coast through periodic re-nourishment. While conceptual models of the coastal-economic system provide a capital-theoretic framework to study beach management, empirical analysis of the drivers of beach nourishment policy is limited. Using data from 21 coastal towns in North Carolina, we examine the geophysical and economic factors that reflect coastal vulnerability and influence the frequency of beach nourishment investments. We find that beach towns with access to periodically replenishable sand deposits from inlets and river channels nourish more frequently. Beaches that rely on offshore sand reserves are nourished less frequently. Our results provide new insights into the heterogeneous risks that local communities face with higher costs, limited sand reserves and the growing nourishment demand driven by climate change and increased vulnerability.

Best Fitting Methods for The Mud Profile Equations

In order to understand the dynamics of shoreline changes due to natural and anthropogenic causes, it is imperative for a coastal manager to comprehend the shore profile characteristics which are dependent on the sediment-wave interaction and can be depicted in a profile equation. Moreover, it is possible to derive the power form for the profile equation of a sandy coast based on the argument of wave energy dissipation per unit bed area and unit time. By using this same argument and considering the phenomenon that the main cause of wave damping over a muddy coast is due to energy absorption by the soft mud bottom, the mud profile equation can also be formulated. The aim of this study was to observe the mud profile equation geometry using best fitting method and to compare the characteristic features of the mud profiles using the field observation data. Shore profile data were measured from the muddy coast of Pantai Cermin in the eastern coast of North Sumatera Province. The data obtained were fitted to both the sand and mud profile equations. The procedures and results of the two best fitting methods, the nonlinear regression and the least square based trial and error search, were exhibited and compared. Several noteworthy features of the mud profile equation were found to be the same with the sand profile equation in describing the profile data. In order to provide a better profile and shoreline stabilization, it is recommended to use more complete observation data and good knowledge of shore profile by the coastal manager.

The impact of thermal power stations on coastline and benthic fauna: Case study of El-Burullus power plant in Egypt

Similar to all the coastal power plants, El-Burullus power plant requires significant amounts of seawater for cooling purposes, where the withdrawn water (6.6 ​m3/Sec) from the Mediterranean Sea circulates through the cooling system and then returns to Sea via the outfall (5.5-m3/Sec). The cooling water has a high temperature and salinity from ambient water at the outfall. The effluents discharge from power plants cause impacts that require investigation or monitoring. Thence, this study was undertaken to evaluate the influence of thermal power plant’s cooling liquid and their structures (intake and outfall) on benthic fauna off the coast of the power plant and the efficiency of the power station, besides the shoreline stability alongshore the west coast of El-Burullus city, Egypt. The study was carried out by numerical modeling and field measurements; the Delft3D-FLOW model is used to examine the thermal and brine plume behavior under various hydrodynamic. The shoreline stability was estimated using the Digital Shoreline Analysis System (DSAS) depending on a time series of shoreline vector data for nine years (2010–2018). Results manifested that the location of the intake pipe head is enough further away from the discharge point to allow for mixing the thermal effluents with the ambient seawater at the outfall and reducing their temperature and salinity before reaching the intake. So, the cooling water recirculation doesn’t affect the operational efficiency of the power plant. El-Burullus station hasn’t any effects on the benthic life organisms which grow far from the outfall site but has negative effects on those lived close to the discharge zone. Also, the morphological results of shoreline revealed that the power plant has slightly negative effects on the stability of the coastline. However, notable erosion occurred on the downdrift side of the outfall (−5.5 ​m/yr), and an accretion occurred on its updraft (9 ​m/yr). As a mitigation, it is recommended to compensate shore eroding at the downdrift side by applying sand bypassing technique.

Shore Line Mathematical Modelling and Integrated Groundwater Potentiality Study in the Northern Coast Mediterranean Sea, Egypt

The purpose of this research is to determine surface and subsurface features in the proposed sites. Meanwhile accessibility and availability of water resources. It will have carried out a comprehensive investigations related to topography, geology, hydrology and geophysics. Water samples were collected from the study area and its surroundings to be subjected to different analysis procedures for quality and quantity. The results of the hydrologic analysis showed that all rainfall amounts are infiltrated to the soil and there is no runoff flood water to affect the study area. Consequently, it's concluded that the flood has no harm effect on any of the study area buildings. Based on the geophysical and hydrogeological results, it is strongly recommended drilling three productive wells to a depth of ±50 m at the location of Vertical Electrical Sounding VESes 5 and 7 to produce water from the coral reefs limestone layer where its high fracture density and lower salinity. For future sustainable development plans, it is also possible to drill any number of productive wells in the southern part of the area to avoid the higher degree of sea water intrusion. In this case, the distance between wells must be not less than 120 m. It is conducting a numerical simulation to the coast of the study area in order to inspect the effects of implementing these structures. For that reason, a topographical and a bathymetrical survey were carried to the area in order to simulate the area numerically. The shoreline stabilization was simulated using 20 different orientations to the intake and outlet structures. Based on the mathematical modeling results, it was noticed that the shoreline is naturally stable as it is a smooth East-West shoreline with no undulations and the amount of sediment transport is trivial.

Evolving sediment dynamics due to anthropogenic processes in upper Chesapeake Bay

Like many estuaries, the upper Chesapeake Bay effectively traps sediment from its tributaries and shorelines. However, evolving sediment dynamics from human influences such as increased soil conservation, dam construction (and subsequent infill), and increased shoreline stabilization have altered sediment loads to the Bay. Sediment budgets are important tools for evaluating sediment dynamics through identifying sources, sinks, and transport pathways. The most recent upper Bay sediment budget was developed >25 years ago and does not reflect the evolution of sediment delivery. The objective of this study is to develop an updated sediment budget through quantitative analysis of the upper Bay's major sediment sources (Susquehanna River and shoreline erosion) and sinks (deposition in the Susquehanna Flats region and mainstem Bay). Results indicate that Susquehanna River input to upper Bay has decreased during low flows, due to implementation of conservation-management strategies, but increased during high flows, from infilling of the Conowingo Reservoir. Inputs from shoreline erosion have decreased due to increased shoreline stabilization. Mass accumulation rates in the upper Bay generally decrease with distance downstream, but elevated sedimentation rates occur in deeper water, and possibly represent sediment focusing near channels. Insights gained from this study not only inform sediment management strategies in the Bay and similar systems, but also can help forecast potential future trajectories from environmental and anthropogenic drivers. For example, changing climate is projected to increase precipitation, storminess, and sea-level rise (SLR), which would increase both Susquehanna River and shoreline erosion sediment inputs. These changes could help the sedimentation rates keep pace with SLR but also may degrade downstream ecosystems due to increased fine-sediment input and turbidity. Shoreline stabilization will also likely increase, which would reduce shoreline erosion and thus sand inputs necessary for some nearshore benthic habitats to keep pace SLR.

Effects of Substrate (Protection and Type) on Ribbed Mussel (Geukensia demissa) Recruitment for Living Shoreline Applications

Moody, J.A.; Gentry, M.J.; Bouboulis, S.A., and Kreeger, D.A., 2020. Effects of substrate (protection and type) on ribbed mussel (Geukensia demissa) recruitment for living shoreline applications. Journal of Coastal Research, 36(3), 619–627. Coconut Creek (Florida), ISSN 0749-0208.Ribbed mussels are the functional dominant species in eastern U.S. salt marshes, providing particulate nutrient filtration and enhanced vegetative growth services. Wetland loss in the Delaware Estuary has resulted in ribbed mussel population declines and increased interest in ecological restoration practices, such as living shorelines. Incorporation of ribbed mussels into restoration applications represents an opportunity to enhance ecological structure and function in shoreline stabilization projects. Since 2008, the Partnership for the Delaware Estuary has implemented 14 living shorelines, with ribbed mussel recruitment exhibiting temporal and spatial variability. To better understand sources of this variability, a three-tiered study was employed to evaluate differences in ribbed mussel recruitment: (1) on previously deployed substrates (2009–10); (2) on exposed vs. protected surfaces; and (3) across a variety of substrates. Results showed that on aged living shorelines, ribbed mussel density was greater on oyster shell bags than on coir fiber logs and the unaltered marsh edge. On newly deployed experimental materials, recruitment was higher on the surface of shell bags when protected by mesh but was only <8% of total bag recruitment and did not differ between protected and unprotected shell bags. Mussel recruitment was greater on oyster shell and Oyster Castle® than on coir fiber recruitment tiles, and also on those protected by shell bag mesh than by coir fiber or without protection. Therefore, living shorelines that incorporate ribbed mussel refuge in the form of protected surfaces and interstitial space can facilitate recruitment and persistence, enhancing populations and their associated water quality services.

Correlation Between Shoreline Change and Planform Curvature on Wave‐Dominated, Sandy Coasts

AbstractLow‐lying, wave‐dominated, sandy coastlines can exhibit high rates of shoreline change that may impact coastal infrastructure, habitation, recreation, and economy. Efforts to understand and quantify controls on shoreline change typically examine factors such as sea‐level rise; anthropogenic modifications; geologic substrate, nearshore bathymetry, and regional geography; and sediment grain size. The role of shoreline planform curvature, however, tends to be overlooked. Theoretical and numerical model considerations indicate that incident offshore waves interacting with even subtle shoreline curvature can drive gradients in net alongshore sediment flux that can cause significant erosion or accretion. However, these predictions or assumptions have not often been tested against observations, especially over large spatial and temporal scales. Here, we examined the correlation between shoreline curvature and shoreline change rates for spatially extended segments of the U.S. Atlantic and Gulf Coasts (~1,700 km total). Where shoreline stabilization (nourishment or hard structures) does not dominate the shoreline change signal, we find a significant negative correlation between shoreline curvature and shoreline change rates (i.e., convex‐seaward curvature [promontories] is associated with shoreline erosion, and concave‐seaward curvature [embayments] with accretion) at spatial scales of 1–5 km alongshore and timescales of decades to centuries. This indicates that shoreline changes observed in these reaches can be explained in part by gradients in alongshore sediment flux acting to smooth spatial variations in shoreline curvature. Our results suggest that shoreline curvature should be included as a key variable in modeling and risk assessment of coastal change on wave‐dominated, sandy coastlines.

MIKOKO: A Data Sharing Platform On Kenyan Mangrove Species

The Mangrove ecosystem offers a range of benefits and opportunities for local and national economic development such as fisheries, shoreline stability, and resource sustainability hence they should be protected and conserved. In Kenya Mangroves were declared government reserve forests by the Proclamation No. 44 of 30th April 1932, and later by Legal Notice No. 174 of 20th May 1964. Under this “Gazette Notification for Mangrove Forests in Kenya” all land between high water and low water marks (ordinary spring tides) are described as mangrove areas. These forests cover about 61,279ha representing approximately 3% of the natural forest cover or less than 1% of the national land area. Mangrove forests are found in tidal estuaries, creeks, and protected bays along the 536 km long Kenyan coastline that extends from the Kenya-Tanzania border in the south to the Kenya-Somalia border in the north; between latitudes 1°40΄S and 4°25΄S and longitudes 41°34΄E and 39°17΄E. Mikoko (Mangrove in Swahili) is the first project specifically developed for mangrove areas in Kenya. Driven by the Kenya Forest Service, the project takes into account the recommendations of the National Mangrove Ecosystem Management Plan 2017-2027. For effective management of mangroves in the country, the Plan is organised around six programmes including; forest conservation and utilization; fisheries development and management; community; tourism development; research and education; and human resource and operations. These programmes prescribe measures for rehabilitation, conservation, and sustainable management of mangrove ecosystems in Kenya. Implementations of this Plan will be led by Kenya Forest Service (KFS); but will also include other key actors such as Kenya Wildlife Service, State Department of Fisheries, Research Institutions, Academia and Community Forest Associations through a specially constituted National Mangrove Advisory Committee. The project is for a 2-year period during which it shall develop an effective system for management of mangrove resources in Kenya. This will be done through the development of management prescriptions, skills improvement and provision of adequate infrastructure as recommended by the mangrove plan. Biodiversity information on mangroves, covering species descriptions and distribution, is essential for understanding the ecology and distribution of this endangered ecosystem and its management. Nowadays, very few is done in that domain. If the mangroves location are well know, it's not the case regarding the species distribution. Citizen science is a way to address this important issue. MIKOKO, a French FSPI funded project, is focused on Kenya to develop species information systems on mangrove species. Mikoko aims to assimilate knowledge through its participatory portal to strengthen a science and technology network of stakeholders such as scientists and parataxonomists in the African region. The portal platform will contain a Citizen Science module, a graphic driven species identification module, a species pages module conforming to Species Profile Model and a spatial module. Subscribing to open data paradigm, all the data on the portal will be covered by Creative Commons license framework. Mobile applications for identifying 60 plant species and contributing to citizen science module will be deployed. The oral presentation will expose the portal features and related apps seeking participation from the environmentalists from the African region.

Defining boat wake impacts on shoreline stability toward management and policy solutions

Coastal economies are often supported by activities that rely on commercial or recreational vessels to move people or goods, such as shipping, transportation, cruising, and fishing. Unintentionally, frequent or intense vessel traffic can contribute to erosion of coastlines; this can be particularly evident in sheltered systems where shoreline erosion should be minimal in the absence of boat waves. We reviewed the state of the science of known effects of boat waves on shoreline stability, examined data on erosion, turbidity, and shoreline armoring patterns for evidence of a response to boat waves in Chesapeake Bay, and reviewed existing management and policy actions in Chesapeake Bay and nearby states to make recommendations for actions to minimize boat wake impacts. In the literature, as well as in our analyses, boat wake energy may be linked to elevated turbidity and shoreline erosion, particularly in narrow waterways. In Chesapeake Bay, three lines of evidence suggest boat waves are contributing to shoreline erosion and poor water clarity in some Bay creeks and tributaries: 1) nearshore turbidity was elevated in many waterways during periods of expected high boating activity, 2) armoring was placed along about a quarter of the low energy shorelines of three examined tidal creeks that are exposed to relatively high boating pressure, and 3) 15% of the shorelines we examined throughout the Bay (9000 km) are low energy shorelines that are experiencing high erosion (≥0.3 m/yr) that cannot be attributed to wind wave energy. Still, there remain significant data gaps that preclude the determination of the overall contribution of boat waves to shoreline erosion throughout the Bay, notably, shoreline erosion data in low energy waterways, recreational boating traffic patterns, and nearshore bathymetry. Interim protective measures can be (and have been) applied in high risk waterways, such as small, low energy waterways that have high recreational boating activity, to help reduce shoreline erosion. Policy options used in Bay states and elsewhere include setbacks from the shore, wake restrictions, and speed restrictions; other more restrictive policies may include prohibition on boats of a certain size or limiting the number of passages. Finally, a systems-approach to boat wake impact management using uniform boat wake policies is likely to be the most effective for consistent shoreline protection.

The Relative Role of Mangroves on Wave Erosion Mitigation and Sediment Properties

Fringe mangroves face waves daily and are thought to protect against erosion in low wave energy sites and undergo erosion if exposed to high wave energy. We aimed to understand the effects of fringe mangroves on erosion and sediment dynamics and of wave exposure on seedling density at three sites of increasing wave energy. Sediment properties (mean grain size, sorting, and bulk density) were assessed within each site in unvegetated and mangrove-vegetated shores in wet and dry seasons. In addition, we estimated seasonal erosion/accretion rates for 2.4 years and seedling density in two zones from the forest edge with contrasting wave exposure. Regression analysis was carried out to explain sediment properties and erosion rate variance in response to the vegetation volume that opposes wave energy and to explain erosion rates in response to wave energy. Mangrove-vegetated shores reduced erosion rates from 3 to 15 times in the two sites with higher wave energy, while the vegetated site with the lowest wave energy experienced accretion compared to minor erosion along the unvegetated shore. Shores with greater Rhizophora mangle basal areas and vegetation volumes favored deposition of particles with low settling rates, different sediment classes, reduced erosion rates, and increased shoreline stability. Mangrove seedling density decreased between 2 and 43 times from the low wave exposure zone to the high wave exposure zone at the forest edge in studied sites. In order to increase vegetation volume, coastal adaptation based on mangroves must limit human disturbances and facilitate epiphytic relationships with oysters.

Using Expert Elicitation to Determine the Relative Impact of Coastal Modifications on Marine Turtle Nesting Grounds

Marine turtles utilize sandy beaches as nesting grounds, which can be impacted by a variety of coastal modifications. In the context of limited resources, managers need to prioritize which impacts from coastal modifications to mitigate. However, data on the relative impacts of coastal modification activities are not often available. To address this, we determined the perceived relative impact of twelve coastal modification activities on marine turtle nesting grounds by eliciting information from researchers and managers who are experts on the impacts of coastal modifications on marine turtles and their nesting grounds. Experts were asked to answer a series of pair-wise comparison matrices that compared the impacts of each coastal modification activity. Beach armoring, light pollution, and other shoreline stabilization structures (such as groins and jetties) were weighted by our experts as having the greatest impact to marine turtle nesting grounds and nonpermanent coastal modifications (e.g., special events and beach cleaning) were weighted by experts as having the lowest impact to marine turtle nesting grounds. Managers can use this information to prioritize their efforts and resources to manage marine turtle nesting grounds if funds are available and policy allows.

Effect of Tidal Stage on Sediment Concentrations and Turbulence by Vessel Wake in a Coastal Plain Saltmarsh

Vessel generated waves can impact shoreline stability and habitat structure in many waterways. Sheltered regions, such as coastal plain saltmarshes, support fragile ecosystems and can be particularly vulnerable to the effects of unregulated vessel operations. Instruments for measuring currents and sediment concentration were deployed in a coastal plain saltmarsh to examine the small-scale physical characteristics of the vessel wake generated by recreational craft typical of this environment. The response to vessel wake varied sharply depending upon the stage of the tide. At low tide, waves breaking on the exposed bank produced high concentrations of suspended material that were transported offshore through turbulent diffusion. When the water elevation exceeded the toe of the marsh scarp, the concentration and turbulent kinetic energy exhibited less of a statistically significant variation in response to vessel passage. For the most energetic flows, the vessel orbital velocities were dwarfed by turbulent fluctuations generated by the sheared tidal boundary layer. While further research is required, preliminary findings indicate that the dissipation of vessel wake energy may stimulate or enhance shear generated turbulence if the characteristic wave period is similar to the characteristic time scale of the energy containing eddies.

BIM Data Exchange Standard for Hydro-Supported Structures

With the rapid adoption of building information modeling (BIM) across diverse industries, the need for a universal standard for BIM data exchanges has become critical for the success of BIM applications. Questions of the level of development and interoperability of BIM as methods to exchange data and integrate various model-based applications into an efficient work process have come to the forefront of BIM standardization to improve the design and construction of facilities. Current BIM software authoring tools center on conventional structural systems and are not yet adequate for modeling floating structures. Hydro-supported structures comprise a special type of structure that relies primarily on the hydraulic buoyancy of the supporting water body to maintain equilibrium and safety. It is an area that is increasingly drawing the attention of architects and engineers to resolve many issues in coastal areas and to deal with issues related to increased flooding and tropical storms, such as shoreline stabilization, hurricane response, alternative energy, and rainwater collection and utilization. The study centers on expanding BIM standardization for designing and analyzing floating and amphibious structures. It seeks to address the information delivery manual (IDM) and model view definitions (MVDs) as they provide the basis for data exchange specifications for the industry foundation classes (IFC) schema. This research aims to enable a proficient BIM workflow for designing hydro-supported structures characterized by the coherent, organized, and reproducible exchange of consistent data that is commonly recognized across the architecture, engineering, and construction (AEC) industry.

Analysis of Changes in Area and Density of Mangroves through Landsat 8 Satellite Image Processing

Mangrove forests have high ecological, economic and social values ??which function to maintain shoreline stability, protect beaches and riverbanks, filter and remediate waste, and to withstand floods and waves. The facts show that mangrove damage is everywhere, even the intensity of damage and its area tends to increase significantly. Many roles of mangroves require proper management to maintain the existence of mangroves. One way to determine the area of ??mangroves is by processing Landsat 8 satellite imagery. The stages of mangrove identification are carried out by using 564 RGB band merger, then separating the mangrove and non-mangrove objects. Next step is to analyze the density of mangroves using NDVI formula. To maximize monitoring of mangrove area, an android application was created that provides information on the area and density of mangroves at several locations, namely Clungup, Bangsong Teluk Asmara and Cengkrong from 2015 to 2018.The results showed that Landsat 8 satellite imagery can be used to identify changes in the area of ??mangrove forests with good accuracy, namely in the Clungup area of ??90% and Cengkrong of 86.67%. From processing results, the mangrove area in the Clungup area has also decreased from 2015 to 2017 but has increased in 2018 so that the application provides recommendations for embroidering mangroves in 2016 to 2017 and mangrove recommendations are maintained in 2018. As for Bangsong Teluk area Asmara and Cengkrong have increased the area of ??mangroves every year so that the application provides recommendations to be maintained from 2016 to 2018.

Oyster reef enhancement utilizing gardened oysters in a subtropical estuary

Crassostrea virginica, the eastern oyster, is a native foundational species that inhabits coastal and estuarine ecosystems along the western Atlantic seaboard. Introduction of C. virginica into estuarine areas with limited or no extant populations is gaining popularity as a pro‐active approach for improving estuarine water quality and creating natural wave breaks for shoreline stabilization. Adult oysters, grown by 113 community members under their private docks, were collected and deployed at three county‐owned sites along the Indian River Lagoon within Brevard County, Florida. In this shallow, warm‐water estuary, replicate treatments deployed at each site included bagged adult oysters collected from gardeners in fall 2014, bagged adult oysters from spring 2015 gardeners, bagged blank (clean) shell, and empty plots (control). Prior to deployment, morphometric data (shell length, weight) were collected on all gardened oysters. Morphometric data were then collected quarterly for all surviving and recruited oysters for 18 months. Our monitoring timeframe was sufficient for assessing survival of gardened oysters, but likely not sufficient to understand recruitment patterns. In areas with no recruitment and limited gardened oyster survival, regular enhancement with live oysters would be needed for long‐term success. In areas with natural recruitment, the blank shell treatment was most successful. Lessons learned from this study include: (1) need for better tracking of abiotic variables (e.g. salinity) where gardening occurred, (2) role of seasonality in initial post‐deployment survival, even in a warm‐water estuary, and (3) importance of pilot studies prior to large‐scale gardened oyster deployments.

What we know and what we think we know: Revealing misconceptions about coastal management for sandy beaches along the U.S. Atlantic Seaboard

Management of coastal areas is necessary to maintain and protect existing permanent structures. Coastal erosion management falls into soft and hard shoreline stabilization options with the United States tending to favor hard. However, post-Hurricane Sandy 2012, soft dune and beach replenishment have become more favorable in the U.S. with support being necessarily contingent upon an understanding of the pros, cons, and concepts surrounding each management strategy. Misconceptions could thus lead to a halt in progress and poor decisions with implications for community safety. We sought to gain a better understanding of current knowledge surrounding best practices in coastal management communities. Our assumption was that misconceptions in one coastal area, New Jersey, are likely echoed in other coastal areas in the U.S. and internationally. We employed a two-phase research design with an exploratory phase using semi-structured interview guidelines to collect data from a quota sample of 53 local residents and then tested the distribution of knowledge about coastal management facts by asking a convenience sample of 300 residents a structured set of 15 questions. Study participants identify differences in how beaches are managed and how protected they conversely consider an area to be. Dunes are generally preferred over hard engineering and replenishment. However, many key concepts regarding how dunes function naturally, with regards to the role of vegetation and fencing, are poorly understood suggesting a need for greater education surrounding these topics. Participants support continued tax investment in coastal areas to avoid retreat but recognize a tragedy of the commons in such actions for future generations. Learning who knows what, may contribute to more fruitful dialogues among stakeholders to pave the way for the adoption of suitable and sustainable management practices for better protected shorelines.

An integrated high-resolution geophysical and geologic visualization of a Lake Bonneville shoreline deposit (Utah, USA)

Pilot Valley, located in the eastern Basin and Range, Western Utah, USA, contains numerous shorelines and depositional remnants of Late Pleistocene Lake Bonneville. These remnants present excellent ground-penetrating radar (GPR) targets due to their coherent stratification, low-clay, low-salinity, and low moisture content. Three-dimensional GPR imaging can resolve fine-scale stratigraphy of these deposits down to a few centimeters, and when combined with detailed outcrop characterization, it provides an in-depth look at the architecture of these deposits. On the western side of Pilot Valley, a well-preserved late Pleistocene gravel bar records shoreline depositional processes associated with the Provo (or just post-Provo) shoreline period. GPR data, measured stratigraphic sections, cores, paleontological sampling for paleoecology and radiocarbon dating, and mineralogical analysis permit a detailed reconstruction of the depositional environment of this well-exposed prograding gravel bar. Contrary to other described Bonneville shoreline deposits, calibrated radiocarbon ages ranging from 16.5 to 14.3 (ka, BP) indicate that the bar was stable and active during an overall regressive stage of the lake, as it dropped from the Provo shoreline (or just post-Provo level). Our study provides a model for an ancient pluvial lakeshore depositional environment in the Basin and Range province and suggests that stable, progradational bedforms common to the various stages of Lake Bonneville are likely not all associated with periods of shoreline stability, as is commonly assumed. The high-resolution GPR visualization demonstrates the high degree of compartmentalization possible for a potential subsurface reservoir target based on ancient shoreline sedimentary facies.

Blue Carbon: an Additional Driver for Restoring and Preserving Ecological Services of Coastal Wetlands in Tampa Bay (Florida, USA)

Coastal habitats, including mangroves, salt marsh, and seagrass meadows, provide numerous ecosystem services, including improved water quality, shoreline stabilization, and essential fish habitat. Over the past few decades, the quantification of greenhouse gas fluxes in wetlands has improved, leading to the recognition of these habitats as long-term carbon sinks. Quantifying this “blue carbon” as an ecosystem service provides added value for wetland protection and restoration and serves as a useful management tool when implementing plans for sustained ecosystem health and productivity. Tampa Bay (Florida, USA), a highly urbanized estuary, provides an interesting case study to assess the role of blue carbon in supporting management and informing restoration decisions. This review provides results from the Tampa Bay Blue Carbon Assessment, which quantified existing carbon stocks and identified the future carbon sequestration trajectories of coastal habitats with respect to climate change and sea-level rise. Examples are provided of how these data can be used to prioritize restoration efforts, support and enhance management decisions, and potentially attract new partners to support wetland restoration projects that offer additional climate change mitigation and adaptation benefits. This added valuation can help drive investment towards additional wetland restoration activities to help meet management targets in estuaries worldwide.