Coral Reefs

, Volume 33, Issue 4, pp 1003–1015

Nitrogen fixation rates in algal turf communities of a degraded versus less degraded coral reef

Authors

  • Joost den Haan
    • Department of Aquatic Microbiology, Institute for Biodiversity and Ecosystem DynamicsUniversity of Amsterdam
    • Department of Aquatic Microbiology, Institute for Biodiversity and Ecosystem DynamicsUniversity of Amsterdam
  • Anjani E. Ganase
    • Department of Aquatic Microbiology, Institute for Biodiversity and Ecosystem DynamicsUniversity of Amsterdam
    • Coral Reef Ecosystems Lab, School of Biological SciencesThe University of Queensland
  • Elfi E. Gooren
    • Department of MicrobiologyRadboud University
  • Lucas J. Stal
    • Department of Aquatic Microbiology, Institute for Biodiversity and Ecosystem DynamicsUniversity of Amsterdam
    • Department of Marine MicrobiologyRoyal Netherlands Institute for Sea Research (NIOZ)
  • Fleur C. van Duyl
    • Department of Biological OceanographyRoyal Netherlands Institute for Sea Research (NIOZ)
  • Mark J. A. Vermeij
    • Department of Aquatic Microbiology, Institute for Biodiversity and Ecosystem DynamicsUniversity of Amsterdam
    • Carmabi Foundation
  • Jef Huisman
    • Department of Aquatic Microbiology, Institute for Biodiversity and Ecosystem DynamicsUniversity of Amsterdam
Report

DOI: 10.1007/s00338-014-1207-5

Cite this article as:
den Haan, J., Visser, P.M., Ganase, A.E. et al. Coral Reefs (2014) 33: 1003. doi:10.1007/s00338-014-1207-5

Abstract

Algal turf communities are ubiquitous on coral reefs in the Caribbean and are often dominated by N2-fixing cyanobacteria. However, it is largely unknown (1) how much N2 is actually fixed by turf communities and (2) which factors affect their N2 fixation rates. Therefore, we compared N2 fixation activity by turf communities at different depths and during day and night-time on a degraded versus a less degraded coral reef site on the island of Curaçao. N2 fixation rates measured with the acetylene reduction assay were slightly higher in shallow (5–10-m depth) than in deep turf communities (30-m depth), and N2 fixation rates during the daytime significantly exceeded those during the night. N2 fixation rates by the turf communities did not differ between the degraded and less degraded reef. Both our study and a literature survey of earlier studies indicated that turf communities tend to have lower N2 fixation rates than cyanobacterial mats. However, at least in our study area, turf communities were more abundant than cyanobacterial mats. Our results therefore suggest that turf communities play an important role in the nitrogen cycle of coral reefs. N2 fixation by turfs may contribute to an undesirable positive feedback that promotes the proliferation of algal turf communities while accelerating coral reef degradation.

Keywords

Algal turfBenthic cyanobacteriaCoral reefsNitrogen cycleN2 fixation

Supplementary material

338_2014_1207_MOESM1_ESM.docx (34 kb)
Supplementary material 1 (DOCX 33 kb)

Copyright information

© Springer-Verlag Berlin Heidelberg 2014