15 May 2023
 | 15 May 2023
Status: this preprint is open for discussion.

Storm characteristics influence nitrogen removal in an urban estuarine environment

Anne Margaret H. Smiley, Suzanne P. Thompson, Nathan S. Hall, and Michael F. Piehler

Abstract. Sustaining water quality is an important component of coastal resilience. Floodwaters deliver reactive nitrogen (NOx) to sensitive aquatic systems and can diminish water quality. Coastal habitats in flooded areas can be effective at removing reactive nitrogen through denitrification (DNF). However, less is known about this biogeochemical process in urbanized environments. This study assessed the nitrogen removal capabilities of flooded habitats along an urban estuarine coastline in the upper Neuse River Estuary (NRE), NC, USA under two nitrate concentrations (16.8 µM and 52.3 µM NOx, respectively). We also determined how storm characteristics (e.g., precipitation and wind) affect water column NOx concentrations and consequently DNF by flooded habitats. Continuous flow-through sediment core incubation experiments quantified gas and nutrient fluxes across the sediment-water interface in marsh, swamp forest, undeveloped open space, stormwater pond, and shallow subtidal sediments. All habitats exhibited net DNF. Additionally, all habitats increased DNF rates under elevated nitrate conditions compared to low nitrate. Structured habitats with high sediment organic matter had higher nitrogen removal capacity than unstructured, low sediment organic matter habitats. High precipitation-high wind storm events produced concentrations significantly lower than other types of storms (e.g., low precipitation-high wind, high wind-low precipitation, low wind-low precipitation), which likely results in relatively low DNF rates by flooded habitats and low removal percentages of total dissolved nitrogen loads. These results demonstrate the importance of natural systems to water quality in urbanized coastal areas subject to flooding.

Anne Margaret H. Smiley et al.

Status: open (until 10 Jul 2023)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse

Anne Margaret H. Smiley et al.

Anne Margaret H. Smiley et al.


Total article views: 102 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
74 27 1 102 2 2
  • HTML: 74
  • PDF: 27
  • XML: 1
  • Total: 102
  • BibTeX: 2
  • EndNote: 2
Views and downloads (calculated since 15 May 2023)
Cumulative views and downloads (calculated since 15 May 2023)

Viewed (geographical distribution)

Total article views: 106 (including HTML, PDF, and XML) Thereof 106 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
Latest update: 07 Jun 2023
Short summary
Floodwaters can deliver reactive nitrogen to sensitive aquatic systems and diminish water quality. We assessed the nitrogen removal capabilities of flooded habitats and urban landscapes. Differences in processing rates across land cover treatments and between nutrient treatments suggest that abundance and spatial distributions of habitats, as well as storm characteristics, influence landscape-scale nitrogen removal. Results have important implications for coastal development and climate change.