Organic geochemical studies of modern microbial mats from Shark Bay: Part I: Influence of depth and salinity on lipid biomarkers and their isotopic signatures

A study of microbial mats in Shark Bay, Western Australiarevealed that depth and salinity significantly influence lipid biomarkers and isotopic signatures. The research found that shallower mats exhibit higher diatom contributions, while deeper mats show increased seagrass-derived organic matter with 13C-depleted long-chain n-alkanes. Salinity variations also affect microbial communities, with high-salinity sites showing dominance of autotrophic biomass using distinct CO2 fixation pathways. The study analyzed lipid biomarkers (e.g., n-C17 and C25:1 HBI) and stable carbon isotopic values across four mat types along a tidal gradient, providing insights into the functional relationships between microbial communities and environmental conditions.

Pagès, A., Grice, K., Ertefai, T., Skrzypek, G., Jahnert, R., & Greenwood, P. (2014). Organic geochemical studies of modern microbial mats from Shark Bay: Part I: Influence of depth and salinity on lipid biomarkers and their isotopic signatures. Geobiology, 12(5), 469–487. Portico. https://doi.org/10.1111/gbi.12094