The ecology of African Soda Lakes: Driven by variable and extreme conditions

Abstract

East African soda lakes are extreme environments that force organisms to cope with high salinities, pH levels and turbidity, but are nonetheless amongst the most productive ecosystems worldwide. We provide an overview of the species inventory in these lakes, which, amongst other fascinating species, host the well-known cyanoprokaryote Arthrospira fusiformis, commercially sold under the name ‘Spirulina’, and large flocks of Lesser Flamingos sometimes reaching densities of over one million individuals per lake. We further discuss physiological adaptations of organisms to the harsh environment as well as the variability of population dynamics and the food web structure of soda lakes. An emphasis is put on the description of environmental drivers and autogenic internal biological dynamics triggering shifts in plankton community composition and the consequences for higher trophic levels. We also elaborate on energy budgets and the importance of aquatic-terrestrial coupling in soda lakes. These are some of the key aspects pointing to promising new avenues for future research on these fascinating ecosystems.