Hot-spring inputs and climate drive dynamic shifts in archaeal communities in Lake Magadi, Kenya Rift Valley

A new study reveals that Lake Magadi, part of Kenya's UNESCO-listed Great Rift Valley, experiences dynamic shifts in archaeal communities driven by hot-spring inputs and climate changes. The research identifies two stable states in the lake: one where tuffaceous silt presence 'switches off' the Methane Index (MI), indicating a hot spring-dominated environment with Thermoproteotal archaea thriving, and another where MI increases, suggesting dominance of methanogenic archaea. These shifts are linked to arid conditions and a shallower lake, supported by carbon isotope data and organic matter analysis. The findings highlight the interplay between hydrothermal inputs and climate in shaping microbial ecosystems over geological timescales.

Collins, E. R., Ferland, T. M., Castañeda, I. S., Owen, R. B., Lowenstein, T. K., Cohen, A. S., Renaut, R. W., O’Beirne, M. D., & Werne, J. P. (2025). Hot-spring inputs and climate drive dynamic shifts in archaeal communities in Lake Magadi, Kenya Rift Valley. Biogeosciences, 22(15), 3931–3948. https://doi.org/10.5194/bg-22-3931-2025