Short-term effects of nereid polychaete size and density on sediment inorganic nitrogen cycling under varying oxygen conditions

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 524:155-169 (2015) - DOI: https://doi.org/10.3354/meps11185 Short-term effects of nereid polychaete size and density on sediment inorganic nitrogen cycling under varying oxygen conditions Jennifer A. Bosch*, Jeffrey C. Cornwell, W. Michael Kemp University of Maryland Center for Environmental Science, Horn Point Laboratory, 2020 Horns Point Rd, Cambridge, MD 21613-0775, USA *Corresponding author: jbosch@umces.edu ABSTRACT: Chronic eutrophication and expanding seasonal hypoxia (O2 < 63 µM) in estuaries like Chesapeake Bay have altered benthic faunal communities in favor of opportunistic species that can quickly populate organic-rich sediments following hypoxic events. It has been suggested that the biogenic activity of polychaetes can stimulate microbial ammonification, nitrification, and/or denitrification in estuarine sediments as well as increase the fluxes of inorganic nitrogen (NH4+, NO2-, NO3-, N2) across the sediment-water interface. Results of 2 laboratory experiments with the opportunistic polychaete Alitta (Neanthes) succinea were used to quantify the short-term influence of density and size of surface-feeding polychaetes on denitrification and sediment-water fluxes of inorganic nitrogen under varying oxygen conditions. This study shows that polychaete enhancements of O2 and nitrogen fluxes were strongly correlated with total animal biomass. Fluxes of O2, NH4+ and N2 were stimulated by presence of animals for both larger and smaller worms, but per capita effects were greater for the deep-burrowing larger polychaetes. With the onset of hypoxic conditions, all density treatments had reductions in O2, NH4+ and N2 fluxes, with the high-density treatment showing the greatest change. Denitrification efficiency was 33% higher for experiments with large worms than for smaller worm treatments, suggesting that the former were more effective in removing fixed nitrogen. KEY WORDS: Polychaetes · Nitrogen cycling · Sediment biogeochemistry · Bioirrigation · Hypoxia · Denitrification · Alitta succinea Full text in pdf format PreviousNextCite this article as: Bosch JA, Cornwell JC, Kemp WM (2015) Short-term effects of nereid polychaete size and density on sediment inorganic nitrogen cycling under varying oxygen conditions. Mar Ecol Prog Ser 524:155-169. https://doi.org/10.3354/meps11185 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 524. Online publication date: March 30, 2015 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2015 Inter-Research.