Long chain alkenones in hypersaline and marine coastal microbial mats

This distribution is different from C37-C40 alkenone mixtures previously found in open sea waters or freshwater environments. It suggests a biological origin distinct from that previously described for marine algal cultures or recent or ancient open sea sediments. The uniformity of the distributions, despite the strong salinity differences considered in the present study (salinity of 35-200) is remarkable. Depth analysis of the microbial mats from hypersaline environments shows fluctuations in total alkenone concentration, but no defined trends involving selective changes in compounds with a specific degree of unsaturation or chain length.