OOS 47-1
Soil hydration shapes microbial interactions - localized trophic interactions and self-organization of microbial consortia on hydrated soil surfaces
Soil hydration shapes microbial interactions - localized trophic interactions and self-organization of microbial consortia on hydrated soil surfaces
Friday, August 15, 2014: 8:00 AM
202, Sacramento Convention Center
Background/Question/Methods:
Microbial life in soil occurs within fragmented pore spaces and aquatic habitats where motility is restricted to thin liquid films that support motion for short hydration windows (following wetting events). The limited ranges of self-dispersion, and the physical confinement, promote spatial association among trophically interdepended microbial species. Considering competing resource requirements and byproduct dependencies of multispecies microbial communities, the spatial organization and functional patterns of such complex diffusion-driven systems remain unclear. We report a mechanistic modeling study of multispecies microbial communities grown on hydrated soil surfaces.
Results/Conclusions:
Model results show how trophic dependencies and cell-level local interactions within patchy diffusion fields lead to niche partitioning and promote spatial self-organization of motile microbial cells. The spontaneously forming patterns of segregated yet coexisting species were shown to be robust to spatial heterogeneities and temporal perturbations (hydration dynamics), and responded primarily to the type of trophic dependencies and boundary conditions (nutrient fluxes at boundaries). The spatially self-organized consortia form ecological templates that optimize nutrient utilization (and potentially other functions), these patterns could form the basis for subsequent sessile and EPS-embedded microbial colonies forming on newly inhabited soil surfaces. The limited spatial range of microbial displacement on surfaces defines a hydration-dependent separation distance for the activation of spatial self-organization (i.e., members separated beyond this distance cannot “join” the consortium). The study provides new mechanistic insights into how differences in nutrient affinities among microbial species may give rise to spatial order in an extremely heterogeneous and complex soil microbial world.
Microbial life in soil occurs within fragmented pore spaces and aquatic habitats where motility is restricted to thin liquid films that support motion for short hydration windows (following wetting events). The limited ranges of self-dispersion, and the physical confinement, promote spatial association among trophically interdepended microbial species. Considering competing resource requirements and byproduct dependencies of multispecies microbial communities, the spatial organization and functional patterns of such complex diffusion-driven systems remain unclear. We report a mechanistic modeling study of multispecies microbial communities grown on hydrated soil surfaces.
Results/Conclusions:
Model results show how trophic dependencies and cell-level local interactions within patchy diffusion fields lead to niche partitioning and promote spatial self-organization of motile microbial cells. The spontaneously forming patterns of segregated yet coexisting species were shown to be robust to spatial heterogeneities and temporal perturbations (hydration dynamics), and responded primarily to the type of trophic dependencies and boundary conditions (nutrient fluxes at boundaries). The spatially self-organized consortia form ecological templates that optimize nutrient utilization (and potentially other functions), these patterns could form the basis for subsequent sessile and EPS-embedded microbial colonies forming on newly inhabited soil surfaces. The limited spatial range of microbial displacement on surfaces defines a hydration-dependent separation distance for the activation of spatial self-organization (i.e., members separated beyond this distance cannot “join” the consortium). The study provides new mechanistic insights into how differences in nutrient affinities among microbial species may give rise to spatial order in an extremely heterogeneous and complex soil microbial world.