Environmental lake bacterium Targeted Locus (Loci). uncultured bacterium

Dispersal among communities should affect community function but the coupling between dispersal and function may depend on the resource use width of taxa. Here, we subjected six bacterial lake water communities from Sweden to four dispersal treatments and analyzed bacterial communities and bulk bacterial production. Resource use width of taxa was determined in a separate re-growth experiment exposing communities to various carbon substrates. Dispersal consistently affected bacterial community composition and richness while bacterial production showed no consistent trend to dispersal treatments. Instead, communities with a higher initial proportion of specialist taxa showed a decrease in production with increasing dispersal, communities with a lower proportion of specialists showed no or a positive effect of dispersal on functioning. We conclude that resource use width of bacteria in the recipient community is important for the effect of dispersal on ecosystem functioning.