also be groups of functionally redundant bacteria or simply
groups of organisms subject to some pressure or process that only
coincidentally led to spatial alignment with one of the modelled
biogeochemical processes. To distinguish these explanations, we
assayed the genetic capability of the OTUs in some OEUs to carry
out the biogeochemical process with which they spatially align.
For example, if all OTUs in an OEU have the genetic capability to
perform some process, then that OEU might represent
functionally redundant organisms. Conversely, if none of those
OTUs has the genetic capability, then that OEU probably has
little to do with biogeochemistry. If only some OTUs in an OEU
can perform some process, then that OEU might represent a
consortium of syntrophic organisms.