Narrow fringing salt marshes dominated by Spartina alterniflora occur naturally along estuarine shorelines and provide many of the same ecological functions as more extensive marshes. These fringing salt marshes are sometimes incorporated into shoreline stabilization efforts. We obtained data on elevation, salinity, sediment characteristics, vegetation and fish utilization at three study sites containing both natural fringing marshes and nearby restored marshes located landward of a stone sill constructed for shoreline stabilization. During the study, sediment accretion rates in the restored marshes were approximately 1.5-to 2-fold greater than those recorded in the natural marshes. Natural fringing marsh sediments were predominantly sandy with a mean organic matter content ranging between 1.5 and 6.0%. Average S. alterniflora stem density in natural marshes ranged between 130 and 222 stems m À2 , while mean maximum stem height exceeded 64 cm. After 3 years, one of the three restored marshes (NCMM) achieved S. alterniflora stem densities equivalent to that of the natural fringing marshes, while percentage cover and maximum stem heights were significantly greater in the natural than in the restored marshes at all sites. There was no significant difference in the mean number of fish, crabs or shrimp captured with fyke nets between the natural and restored marshes, and only the abundance of Palaemonetes vulgaris (grass shrimp) was significantly greater in the natural marshes than in the restored ones. Mean numbers of fish caught per 5 m of marsh front were similar to those reported in the literature from marshes adjacent to tidal creeks and channels, and ranged between 509 and 634 fish net À1 . Most of the field data and some of the sample analyses were obtained by volunteers as they contributed 223 h of the total 300 h spent collecting data from three sites in one season. The use of fyke nets required twice as many man-hours as any other single task. Vegetation and sediment parameters were sensitive indicators of marsh restoration success, and volunteers were capable of contributing a significant portion of the labor needed to collect these parameters.

Abstract. Nutrient enrichment and eutrophication of estuarine and coastal waters are accelerating, and there is a need to develop rapidly detectable and quantifiable indicators of these changes. Coastal systems are also impacted by climatic perturbations, including droughts, storms, and floods, the frequencies of which may be increasing. Phytoplankton are excellent indicators of ecological change. They are relatively easy to detect, identify, and quantify; they conduct a large share of primary production; and they are sensitive to diverse environmental stressors. In this study, phytoplankton total biomass, as chlorophyll a, and group-specific chemotaxonomic indicators (including chlorophylls and carotenoids) were used to characterize community responses to human (nutrient) and climatic (hydrologic) perturbations in the Neuse River Estuary-Pamlico Sound, North Carolina, USA. This estuarine-coastal continuum is experiencing anthropogenic nutrient enrichment and, since 1996, a rise in hurricane frequency. Freshwater input and flushing strongly interacted with supplies of the limiting nutrient nitrogen (N) to determine the location, magnitude, and composition of phytoplankton biomass along this continuum. Elevated flow (high flushing) following hurricanes favored dominance by the fast-growing chlorophytes and cryptophytes. Diatoms tended to dominate under moderate flow, while dinoflagellates and cyanobacteria increased in dominance when low flow prevailed in winter/spring and summer/fall, respectively. Depending on seasonal hydrologic cycles and episodic (hurricane) conditions, phytoplankton community structure differed substantially. These changes impact eutrophication, food web, biogeochemical (e.g., hypoxia), and habitat conditions in this and other coastal ecosystems currently experiencing changes in nutrient inputs and climatic events. Phytoplankton-based indicators are adaptable to unattended monitoring platforms (e.g., ferries) that can be coupled to remote sensing and modeling efforts, in order to evaluate and help manage ecological change at ecosystem and regional scales.

Phytoplankton diagnostic photopigments in near-surface waters (<0.5 m) were identified and quantified by high-performance liquid chromatography beginning in April 1994 in the Neuse River Estuary and in October 1999 in the Pamlico Sound, North Carolina. Photopigment concentrations were analyzed using ChemTax to determine the class-specific biomass of the dominant phytoplankton groups. Long-term annual and seasonal trends in phytoplankton biomass and composition were characterized along the river-estuarine continuum and compared to river flow rates, which were variable because of droughts, uncharacteristic seasonal rainfall patterns, and, since 1996, an increase in the frequency of tropical storms and hurricanes. We tested the hypothesis that temporal and spatial patterns of phytoplankton biomass and composition were largely controlled by changes in river flow rate through associated changes in salinity and residence time or through physical transport and advection of phytoplankton classes with river flow along the estuary. Significant interannual, seasonal, and spatial variability in phytoplankton biomass and composition was observed and coincided with variability in river flow rates. The five dominant phytoplankton classes (Chlorophyceae, Cryptophyceae, Cyanobacteria, Bacillariophyceae, and Dinophyceae) were physically displaced downstream during periods of elevated river flow. Dinoflagellates were reduced in abundance during high flow conditions, especially in the upper Neuse River Estuary. The abundance of cyanobacteria was also reduced throughout the system during elevated river flow conditions, although chlorophytes were more abundant. Changes in hydrology can be a useful indicator of seasonal phytoplankton distribution and higher level compositional changes along hydrologic gradients in these and similar systems.

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Barrier islands within sheltered environments are an important natural defense from severe storm impacts for coastal communities worldwide. Despite their importance, these fetch-limited barrier islands remain understudied and their ability to withstand and recover from storms is not well-understood. Here, we present a case study of Sugarloaf Island in North Carolina that demonstrates the operational use of openly accessible LiDAR and aerial imagery data to quantify synoptic habitat, shoreline, and volumetric change between 2014 and 2020, a period that encompasses four hurricanes and a winter storm event. During this time period, our results show: (1) an 11–13% decrease in marsh and shrub habitat, (2) an average landward shoreline migration of 2.9 m yr−1 and up to 5.2 m yr−1 in extreme areas, and (3) a net volume loss of approximately 9800 m3. The results of this study highlight the importance of storms as a driver of morphologic change on Sugarloaf Island and have implications for better understanding the resiliency of fetch-limited barrier islands to storms. This work helps to enhance prerestoration data availability and supports knowledge-based decision-making regarding habitat change, erosional issues, and the efficacy of nature-based solutions to increase the resiliency of a coastal community in North Carolina.