Macrophyte wrack biomass, sand nitrate concentration, and plant foliar nitrogen metrics from North Carolina Outer Banks beaches and dunes (2016-2020)

This dataset was collected to investigate the variability in macrophyte wrack and marine nutrients delivered to North Carolina (NC) Outer Banks beaches and foredunes and their potential role in shaping dune vegetation productivity. These data were collected at 112 transects along Outer Banks beaches and foredunes from Bogue Banks, NC in the south to False Cape, Virginia in the north. Data collection occurred from 2016 to 2020, including lab sample processing. Wrack samples were collected along a transect at the dune toe, and percent cover of each sample was estimated using a quadrat in the field. Sand samples were collected at the same time. Vegetation samples were also collected at the toe, crest, and heel of the dune for each species present. Wrack and vegetation samples were dried and weighed in the lab following field surveys. Nitrate concentration was measured in each sand sample using KCl extractions, and dune grass foliar nitrogen (%N) and source (δ15N) were measured in ground up tissues via a continuous-flow isotope ratio mass spectrometer.