Carbon isotope variations in a solar pond microbial mat: Role of environmental gradients as steering variables

Calcified microbial mats date prehistoric canals—Radiocarbon assay of organic extracts from travertine

“…The presence of macro-and microfossils of these rapidly growing organisms is evidence that this is the case. The 6 13C of the organic residues average <-24 %, indicating a C3 plant source (Schidlowski et al, 1994), in a n area were most upland species are dryland C4 or CAM types (Smith, 1965).…”

Geochemical and palynological investigation of the Shengli River marine oil shale (China): Implications for paleoenvironment and paleoclimate

“…Hypersalinity itself has been suggested as the cause for these heavy isotope values in microbial mats (Schidlowski et al, 1994). However, a number of studies have demonstrated that this cannot be the only cause since no consistent trends are observed between isotopic composition of microbial mats living at different salinities (des Marais et al, 1989;Schidlowski et al, 1994;Schouten et al, 2001). It was suggested that the high productivity typically encountered in microbial/algal mats is also responsible for the decreased fractionation of 13 C (Schouten et al, 2001).…”

“…Enrichment in 13 C seems to be a common feature in hypersaline systems. Hypersalinity itself has been suggested as the cause for these heavy isotope values in microbial mats (Schidlowski et al, 1994). However, a number of studies have demonstrated that this cannot be the only cause since no consistent trends are observed between isotopic composition of microbial mats living at different salinities (des Marais et al, 1989;Schidlowski et al, 1994;Schouten et al, 2001).…”

Occurrence of photosynthetic microbial mats in a Lower Cretaceous black shale (central Italy): a shallow-water deposit

“…Microbial mats in hypersaline systems are sometimes known to have relatively high 13 C bulk values of up to ¡5‰ (e.g., Schidlowski et al 1984;des Marais et al 1989;Lazar and Eeres 1992;Kenig et al 1994;Trichet et al 2000), which is coherent with that founded in the Hassi Jerbi microbial mat, i.e., ¡13.2‰. It has been suggested that the high productivity typically encountered in microbial mats is also responsible for the decreased fractionation of 13 C (des Marais et al 1989;Schidlowski et al 1994).…”