Nitrogen fixation by Trichodesmium spp. in the Central and Northern Great Barrier Reef Lagoon:relative importance of the fixed-nitrogen load

Abstract

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 186:119-126 (1999) - doi:10.3354/meps186119 Nitrogen fixation by Trichodesmium spp. in the Central and Northern Great Barrier Reef Lagoon: relative importance of the fixed-nitrogen load P. R. F. Bell1,*, I. Elmetri1, P. Uwins2 1Low Isles Research Station and Department of Chemical Engineering, University of Queensland, Brisbane 4072, Australia 2Centre for Microscopy and Microanalysis, University of Queensland, Brisbane 4072, Australia *E-mail: p.bell@mailbox.uq.edu.au ABSTRACT: Studies in the Great Barrier Reef Lagoon (GBRL) show that Trichodesmium (Oscillatoria) spp. fix significant amounts of atmospheric nitrogen and that the loads of 'new' nitrogen introduced by Trichodesmium spp. are at least of the same order as those entering via riverine discharge. The elevated growth of other genera of phytoplankton and hence eutrophication in some sections of the GBRL could now be largely driven by the in situ production of this 'new' nitrogen. Trichodesmium is more prolific in the Central GBRL than in the Northern GBRL and there is evidence that the concentrations of Trichodesmium spp. have increased since the 1928-29 Great Barrier Reef Expedition to Low Isles. It is hypothesised that this increase has resulted from increases in river borne nutrients that would promote N fixation (e.g. phosphorus, iron and dissolved organic matter). It is estimated that the loads of such nutrients have increased several fold since the development of the coastal catchments of Queensland. KEY WORDS: Trichodesmium · Nitrogen fixation · Eutrophication · Great Barrier Reef Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 186. Publication date: September 17, 1999 Print ISSN:0171-8630; Online ISSN:1616-1599 Copyright © 1999 Inter-Research.