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The coastal geomorphological processes of alongshore transport and tidal currents are interacting with the attendant influences of sea-level rise and sediment supply to generate morphosedimentary units in selected estuarine systems. Constrained by the conditions promoted by microtidal situations in barrier island settings, vectors of sediment transport have established spatial sequences of morphologies and sediment types that are components of shellfish habitats. Greater depth and decreasing grain-size toward the mainland are common characteristics in five northeastern U.S. estuarine systems. The patterns are repeated at various scales among the lagoon-type estuaries as well as within the estuarine settings to establish geospatial associations of geomorphology and habitat., Background The basic concept of an estuary is that it is an aquatic system located at the land-sea interface, and it is a transition feature, extending from freshwater to marine [...]

To establish a basis for the utilization of lidar topography as a data source for coastal geomorphological analyses, this study generated statistical metrics of lidar error through the comparison of a June 2014 USGS collection of airborne lidar with a concurrently collected high-accuracy GPS topographical survey collected within the beach and dunes of a portion of Fire Island National Seashore. The examination of bare earth lidar error within the experiment site revealed a complex association between accuracy and environment within the coastal landscape. Accuracy was constrained to better than 50 cm RMSE in areas with vegetated dune topography and, overall, a 38.9 cm RMSE was measured. Higher accuracies were achieved in the flat, non-vegetated beach. A three-dimensional minimization of residuals between the lidar and GPS surveys reduced the total RMSE to 25.2 cm, indicating a correctable systematic offset between the surface generated from the lidar and the true ground surface. [ABSTRACT FROM AUTHOR]

The book is an excellent addition to a genre that is replete with oft-repeated and simple statements regarding impacts of sea-level rise. The author as well as the Natural Resources [...]

Spatial variations in sedimentation during individual tidal cycles were investigated using filter paper traps. The mean mass of sediment deposited in each tidal cycle was higher at the levee edge than at the inner marsh. The mass of sediment decreased with distance from the head of the estuary. There were weak relationships between tidal regime and sediment accumulation. Spatial variations of annual accretion rates were investigated with marker plots. The annual accretion rate at the inner marsh was higher (1.5 to 3.5 cm/y) than that at the tidal river levee edge (0.8 to 3.0 cm/y). Total suspended sediment (TSS) concentrations in the tidal water column indicated that the accretion rate was affected by vegetation. TSS concentrations in the water column leaving the vegetation cover during ebb tidal flows dramatically decreased. There were strong relationships between the concentration of suspended load and accretion rate. The spatial pattern of sedimentation processes at different timescales was mostly due to erosion of the levee edge by tidal flow. The major findings are: (1) The spatial patterns of sedimentation processes at various timescales are different, (2) vertical accretion rates ranged from 0.9 cm/y to 3.5 cm/y, (3) the study area has a depositional regime over the timescale of the present data, (4) the mean and minimum deposition rates in the study area are higher than other cited systems, and (5) the high accretion rate of this area is related to human-induced environmental change, and the sedimentation trajectory is now evolving to a new equilibrium. [ABSTRACT FROM AUTHOR]

Abstract: A century of human manipulation of sediment transport and sediment supply at Sandy Hook spit has generated an evolving suite of geomorphological responses and shoreline management approaches at this public coastal resource. Eventually a major erosion problem was created in a portion of the Gateway National Recreation Area knows as the “Critical Zone”, a location immediately downdrift of the end of a lengthy seawall. In the last three decades, the management approach was to apply beach nourishment to replace the eroded volumes. Projects emplacing from 20000 m3 to 1.7 million m3 of sand in the Critical Zone attempted to counter the erosional trend. However, evolving Park policy sought to identify alternatives to the massive emplacements of sand from offshore sources. Starting in 1997, detailed topographical surveys were begun to track sediment budget in the eroding Critical Zone, and subsequently at Gunnison Beach, a site of sediment accumulation. A new management philosophy of smaller scale restoration of sediment supply in the Critical Zone has emerged. At present, the Gunnison Beach area on Sandy Hook is being monitored to determine its potential for sediment backpassing to the Critical Zone as a means to balance its local sediment budget, create a relatively consistent topography, and maintain the recreational resources. [Copyright &y& Elsevier]

The article discusses the contributions of Jim Allen as coastal geomorphologists at the U.S. National Park Service. Allen devoted his career in scientific inquiry, evaluation of management actions and activities, conservation of coastal national parks' heritage. He is considered as an expert in causes and forecasts of shoreline change, beach/dune dynamics, historical alterations, coastal habitat and evolution of geographical information system. His efforts have tremendous impact on coastal parks in the eastern U.S.

This article examines the suitability and potential advances of decision-theoretic models from finance regarding investment decisions in shoreline stabilization projects. A set of scenarios represents the dynamics of the decision-state facing the planner and identifies factors that should be incorporated into the decision-making process. It is shown that decision models from finance can account for the risk and uncertainty inherent in shoreline stabilization projects, potentially suggest improvements and refinements to presently used cost-benefit analysis procedures, and offer new tools that can aid in decisions concerning provision of shoreline stabilization. The outcomes of these scenarios justify better planning and control of existing and future building, and that of poststorm policies. Lastly, these models allow us to explore the range of our understanding of coastal processes and interactions with shoreline stabilization projects and can identify new and useful data needed in coastal management and hazard management decisions. [ABSTRACT FROM AUTHOR]

Examines the eolian transport triggered by beach nourishments in Riells, Spain. Geomorphological impacts associated with eolian processes; Sediment mobilization within the nourishment area; Coastal sedimentation.

Beach nourishment was applied at three fetch-restricted sites along the estuarine margin of Delaware Bay, New Jersey. Evaluation of geomorphological performance of the nourishment project was conducted through seasonal monitoring to track linear features (shoreline, dune crest, peat edge) and to create digital elevation models (DEMs). Comparisons of the DEMs yielded sediment budgets of the updrift, fill area, and downdrift zones as well as the spatial and temporal evolution of the tidal flat, beach, and dune features within the zones. Through four years, Moore's Beach lost all of the emplaced fill as well as an additional −5446 m3 from the fill area. The shoreline position shifted inland −12.78 m, and the foredune crest shifted inland −9.23 m. The fill area at Pierce's Point lost all of the fill and an additional −3810 m3. The shoreline and dune crest shifted inland −7.35 m and −1.17 m, respectively. The Reed's Beach study area benefited from beach fill updrift that more than offset the losses in the fill area, a net gain of 2107 m3. There was a major contrast in volumetric change between the updrift and downdrift portions. Sediment budget calculations established alongshore transport was an important factor in the fetch-restricted estuarine environment driving the variable geomorphological responses in the updrift, fill, and downdrift zones. [ABSTRACT FROM AUTHOR]