Séminaire de Mécanique d'Orsay
Jeudi 30 juin à 14h au FAST
Life on Partially-Hydrated Rough Surfaces
Dani Or and Gang Wang
Department of Environmental Sciences, ETH Zurich, Switzerland
 

By some accounts exploring microbial diversity found in soils represents a scientific frontier at the scope similar to that of space exploration. The immense diversity of microbial life is attributed to the complex and heterogeneous pore surfaces and spaces with dynamic aqueous and chemical microenvironments. A flickering aqueous network defines nutrient diffusional pathways shapes microbial dispersion. We quantitatively explore effects of microscale hydration on biophysical interactions affecting microbial dispersion and controlling coexistence of competing bacterial species inhabiting unsaturated soil surfaces. Experiments confirm a surprisingly narrow range of hydration-enabled motility and onset of limiting and heterogeneous diffusion fields that promote coexistence even under mild unsaturated conditions. Spontaneous spatial organization of interacting microbial populations and formation of consortia due to dynamic diffusion fields will be presented.