title: Utilization of carbon substrates by heterotrophic bacteria through vertical sediment profiles in coastal and estuarine seagrass meadows.
abstract: Coastal vegetated ecosystems play an important role in carbon cycling and bacterial communities inhabiting coastal sediments are responsible for the remineralization and processing of organic carbon (OC). We collected 1 m-long sediment cores in Posidonia seagrass meadows from coastal and estuarine sites in Australia that differed in their sedimentary organic and inorganic carbon, nitrogen and mud contents. The metabolic diversity of sediment heterotrophic bacterial communities was characterized at different sediment depths, based on the utilization pattern of 31 individual carbon substrates using Biolog EcoPlatesTM. High metabolic diversity was recorded at both sites, but the carbon substrate utilization rates and the use of carbohydrates were higher at the coastal site compared to the estuarine site. The heterotrophic bacterial community in the coastal sediment appeared to metabolize a more diverse OC pool compared to the estuarine site, which might partly explain the differences in OC storage among the seagrass habitats studied. The Biolog EcoPlatesTMprovided a useful tool for characterising the sediment heterotrophic bacterial communities in the meadows and sediment characteristics and biochemical composition of the organic matter played an important role in shaping heterotrophic bacterial communities and their carbon utilization rates, potentially affecting carbon accumulation and preservation within seagrass sediments.
authors.affiliation: Centre For Marine Ecosystem Research, Edith Cowan University, 270 Joondalup drive, Joondalup, WA 6027, Australia.
authors.forename: Christin
authors.initials: C
authors.lastname: Säwström
authors.affiliation: Centre For Marine Ecosystem Research, Edith Cowan University, 270 Joondalup drive, Joondalup, WA 6027, Australia.|The University of Western Australia Oceans Institute, University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.|Centro de Estudios Avanzados de Blanes, Consejo Superior de Investigaciones Científicas. Acceso a la Cala St. Francesc, 14, 17300 Blanes, Girona, Spain.
authors.forename: Oscar
authors.initials: O
authors.lastname: Serrano
authors.affiliation: Centre For Marine Ecosystem Research, Edith Cowan University, 270 Joondalup drive, Joondalup, WA 6027, Australia.|School of Environmental and Natural Resource Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Rozaimi
authors.affiliation: Centre For Marine Ecosystem Research, Edith Cowan University, 270 Joondalup drive, Joondalup, WA 6027, Australia.|Centro de Estudios Avanzados de Blanes, Consejo Superior de Investigaciones Científicas. Acceso a la Cala St. Francesc, 14, 17300 Blanes, Girona, Spain.
authors.forename: Paul S
authors.initials: PS
authors.lastname: Lavery