Rhizosphere effects on functional stability of microbial communities in conventional and organic soils following elevated temperature treatment

The resistance and resilience of soil function may be increased through selection of crops and organic matter inputs. Soil from paired organic or conventional plots was left unplanted or used to grow barley. Substrate induced respiration (SIR) and community level physiological profiles (CLPP) were significantly different in both planted and unplanted systems and in conventional and organically-managed farming systems with no interaction; planted and organic systems had higher SIR. Following heat treatment (30 min at 70 °C), CLPP of planted and unplanted soils in both farming systems changed; a small short-lived decline in SIR only occurred in the planted soils. Differences in the response of these microbial communities to stress may be related to the relative proportions of active and dormant organisms; an increase in functional diversity did not necessarily reflect changed soil function.