DDR Experiments 2013

Understanding how diversity responds to environmental perturbations, and the consequences of this relationship for ecosystem function, are thus central challenges in microbial ecology. Unimodal diversity-disturbance relationships, in which maximum diversity occurs at intermediate levels of disturbance, have been predicted for ecosystems where life-history tradeoffs separate organisms along a disturbance gradient.

However, empirical support for such peaked relationships in macrosystems is mixed, and few studies have explored these relationships in microbial systems. Here we use complex microbial microcosm communities to systematically determine diversity-disturbance relationships over a range of disturbance regimes. We observed a reproducible switch between community types, which gave rise to transient diversity maxima when community types were forced to mix.