Morphological signatures of microbial activity across sediment and light microenvironments of Lake Vanda, Antarctica

Microbial mats in perennially ice-covered Lake Vanda, Antarctica, grow across microenvironments associated with overhanging rocks (a). Microbial mat morphology was documented across gradients in irradiance (b) and siliciclastic sedimentation (c) to assess the role of these environmental parameters on mats. Mat pinnacles and ridges vary in morphology across these environments, but differences are more consistent with changes in the directionality of irradiance rather than the amount of sediment or the absolute level of irradiance. Results illustrate the importance of intrinsic microbial activity to mat morphology, and in this case microbial activity may be influenced by phototactic response of mat communities to the local light environment.464