Microbial consortia in wetland sediments: a biomarker analysis of the effect of hydrological regime, vegetation and season on benthic microbes

• DOI: 10.1071/mf9960027
• Publication Date: 2005-11-18T07:03:02Z
• Authors: PI Boon; P Virtue; PD Nichols
• Keywords: 0301 basic medicine; 03 medical and health sciences; 13. Climate action; 15. Life on land; 6. Clean water

Microbial consortia in the sediments from a permanent wetland near Albury-Wodonga north-eastern Victoria, Australia (Ryans 1 Billabong), and an ephemeral Shepparton central Victoria (Raftery's Swamp) were quantified by analyses of phospholipid fatty acid (PLFA), polar lipid ether (PLEL), sterol alcohol profiles. Prokaryotic organisms dominated benthic assemblages both wetlands. Total prokaryotic abundance (i.e. eubacteria plus archaea) was estimated to be (7-17) × 109 cells g-1 sediment (dry weight). Methanogenic archaea number (1-5.4) account for 11-36% total prokaryotes; these values are apparently among highest recorded temperate lake or river environments. PLFAs indicative specific metabolic groups (e.g. sulfate-reducing bacteria (SRB), methanotrophic bacteria, etc.) also detected. The PLFA profiles indicated that Type I methanotrophs (abundant C16 PLFAs) more abundant than II group, which contain C18 PLFAs. Acetate-utilizing SRB lactate-utilizing SRB, but neither group dominant. Ergosterol not detected, suggested fungi significant component microbial spite wetlands having inputs aquatic fringing vascular plants. Other biomarkers, such as sterols, long-chain alcohols, triterpenoids phytol, demonstrated higher PLFA, PLEL affected hydrological regime, presence vegetation, season. Information this preliminary study may assist making informed management decisions on environmental water allocations natural ecosystems.