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Cretaceous sediments are disconformably overlain by Pliocene sediments along the banks of Greens Mill Run, Greenville, North Carolina, located in the central coastal plain. The Cretaceous sediments, composed of glauconitic sand and clay, have previously been informally considered part of the Maastrichtian Peedee Formation. The Pliocene sediments are assigned to the Yorktown Formation and consist of shelly, muddy sand overlain with a gradational contact by shell-poor, muddy sand. Foraminifera are abundant in the Cretaceous unit and are dominated by the planktic foraminifera Guembelitria cretacea. Low planktic foraminiferal diversity, the absence of single and double-keeled species, the dominance of planktic over benthic foraminifera, and the occurrence of glauconite and phosphorite grains indicates a middle neritic environment. The age of the Cretaceous unit is late Campanian (Zone CC22c), as indicated by the co-occurrence of the calcareous nannofossils Reinhardtites levis and Reinhardtites anthophorus. For this reason, we assign these deposits to the Donoho Creek Formation of the Black Creek Group rather than to the lithologically similar and younger Peedee Formation. Benthic foraminifera dominate the lower part of the Yorktown Formation, are similar to those from the Rushmere Member of the Yorktown Formation in the southern Salisbury Embayment, and indicate deposition in an inner to middle neritic environment. Phosphorite peloids and intraclasts are likely reworked from underlying strata and suggest wave ravinement and deposition during transgression, which is further supported by a fining upward trend. The upper part of the Yorktown Formation exposure, characterized by abundant molds of small bivalves and barren of foraminifera, represents the Morgarts Beach Member. Sedimentological data are consistent with foraminiferal data as far as expected depositional energy. A restricted inner neritic or estuarine environment is indicated. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Pamlico Sound, a large back‐barrier estuary in North Carolina, is under threat of climate change due to increased storm activity and sea level rise. The response of this system is investigated by considering what has already happened during changes in sea level over the late Holocene epoch. The hydrodynamic changes that occurred in response to geomorphic evolution are simulated using a 3‐D numerical model for four distinct "time‐slice" scenarios. To accomplish this, the present‐day bathymetry was obtained from a high‐resolution digital elevation model, and paleobathymetric grids were developed from sediment cores and seismic observations. Using the same hydrodynamic forcing for each geomorphic scenario, the models are compared to assess the combined response to: different inlets connecting the back‐barrier estuary to the ocean, changes in basin geomorphology due to sedimentation, and sea level rise. The results indicate that these factors have a considerable effect on hydrodynamics, waves, and salinity in the estuary. The time‐averaged tidal ranges were up to 3 times as high for the past environments in comparison with present‐day water level elevations, and maximum current velocities were over 3 times higher in regions close to paleo‐inlets. The simulations for each time slice suggest that the salinity distribution in Pamlico Sound is strongly influenced by the hydraulic connectivity with other estuaries and the number and size of tidal inlets through the barrier island system. The results indicate that changes to barrier systems induce strong, nonuniform, and complex responses in back‐barrier estuaries with regime shifts in hydrodynamic energy and water mass properties. Key Points: A modeling approach is developed for simulating the response of an estuary to different geomorphological conditions over a long time scaleGeological observations were used to define inlet locations, basin morphology, and sea levels in the hydrodynamic modelThe results indicate controls on the water levels, current velocities, and salinity distributions in paleo‐estuarine environments [ABSTRACT FROM AUTHOR]

Geological investigations of Herndon Bay, a Carolina bay in the Coastal Plain of North Carolina (USA), provide evidence for rapid basin scour and migration during Marine Isotope Stage (MIS) 3 of the late Pleistocene. LiDAR data show a regressive sequence of sand rims that partially backfill the remnant older portions of the bay, with evidence for basin migration more than 600 meters to the northwest. Basin migration was punctuated by periods of stability and construction of a regressive sequence of sand rims with basal muddy sands incorporated into the oldest rims. Single grain OSL ages place the initial formation of each sand rim from oldest to most recent as ca. 36.7 +/- 4.1, 29.6 +/- 3.1, and 27.2 +/- 2.8 ka. These ages indicate that migration and rim construction was coincident with MIS 3 through early MIS 2, a time of rapid oscillations in climate. The fact that Carolina bay basins can migrate, yet maintain their characteristic shape and orientation, demonstrates that Carolina bays are oriented lakes that evolved over time through lacustrine and eolian processes. This research also indicates that Carolina bays can respond rapidly during periods of climatic transition such as Dansgaard-Oeschger or Heinrich events. [ABSTRACT FROM AUTHOR]

Climate change and sea-level rise will have severe impacts on coastal water resources around the world. However, whereas the influence of marine inundation is well documented in the literature, the impact of groundwater inundation on coastal communities is not well known. Here, core analysis, groundwater monitoring, and ground penetrating radar are utilized to assess the groundwater regime of the surficial aquifer on Bogue Banks Barrier Island (USA). Then, geospatial techniques are used to assess the relative roles and extents of groundwater and marine inundation on the dune-dominated barrier island under sea-level rise scenarios of 0.2, 0.5, and 1.0 m above current conditions by 2100. Additionally, the effects of rising water tables on onsite wastewater treatment systems (OWTS) are modelled using the projected sea-level rise scenarios. The results indicate that the surficial aquifer comprising fine to medium sands responds quickly to precipitation. Water-level measurements reveal varying thicknesses of the vadose zone (>3 to 0 m) and several groundwater mounds with radial flow patterns. Results from projected sea-level rise scenarios suggest that owing to aquifer properties and morphology of the island, groundwater inundation may occur at the same rate as marine inundation. Furthermore, the area inundated by groundwater may be as significant as that affected by marine inundation. The results also show that the proportion of land in the study area where OWTS may be perpetually compromised by rising water tables under worst case scenarios may range from ~43 to ~54% over an 86-year-period. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Micropaleontological, geophysical, and chronologic data indicate that normal salinity conditions occurred over currently estuarine back-barrier areas of the Outer Banks of eastern North Carolina during the peak of the Medieval Climate Anomaly. Sedimentary units several meters thick, containing foraminiferal assemblages usually found on the continental shelf of North Carolina, are present in 16 vibracores acquired from the shallow shoals of Pamlico Sound behind Cape Hatteras. Optically stimulated luminescence age estimates from these normal salinity units range from approximately 1360 to 980 calibrated years (cal yr) BP, corresponding with a previously documented collapse of a segment of the southern Outer Banks. It is vital to understand past scenarios of barrier island formation and segmentation to provide insight on how these islands may react to future change in climate and sea level. [ABSTRACT FROM AUTHOR]

Foraminiferal and sedimentary data, supplemented with geochemical dating and ground-penetrating radar transects, show that the barrier island at Pea Island National Wildlife Refuge just north of Rodanthe, North Carolina, has been dominated by a combination of inlet and overwash processes for at least 1000 years. The stratigraphic record of several vibracores does not preserve every, or even many, overwash events but, instead, is characterized by three to four fining-upward sequences. The last three commence with overwash sand or gravel that is overlain by a variety of finer-grained estuarine, inlet, and marsh deposits. The dynamic nature of this segment of the Outer Banks was muted in the late 1930s by construction of artificial barrier dune ridges, extensive planting of grass and shrubs, and construction of Highway 12 in 1953. Subsequently, the road and barrier dune ridge were rebuilt and relocated several times following storm events. [ABSTRACT FROM AUTHOR]

Reports on a study conducted by researchers in the United States, which examines whether the activity of Leishmania donovani secrete acid phosphatase was affected by treatment with various proteases including some similar to those produced within the gut of their sandfly vector host. Influence of bromelain and subtilisin in causing a pronounced reduction in the enzymatic activity of secrete acid phosphatase.

Examines the correlation between phosphorite presence and the marine delta13C and delta18O records from southeastern United States. Definition of seven phosphogenic episodes on the northeast Florida platform; Estimates of phosphorus burial rates.

Investigates the diversity of the multiple forms of cysteine proteinases of the cattle protozoan parasite Tritrichomonas foetus. DNA sequencing; Growth of trichomonads and preparation of DNA and RNA; Southern and Nothern blotting; Predicted amino acid sequences of TFCP3-9.

Describes the successful cloning of a number of complementary DNAs (cDNAs) encoding cysteine proteinases (CPs). Polymerase chain reaction amplification of genomic DNA encoding CPs; Isolation of CP cDNA clones; Predicted amino acid sequences of TvCP1-4; Genomic organization and expression of TvCP1-4.