The impact of propagule pressure on whole community invasions in biomethane-producing communities

Pawel Sierocinski,Jesica Soria Pascual,Daniel Padfield,Mike Salter,Angus Buckling

doi:10.1016/j.isci.2021.102659

Abstract

SummaryMicrobes can invade as whole communities, but the ecology of whole community invasions is poorly understood. Here, we investigate how invader propagule pressure (the number of invading organisms) affects the composition and function of invaded laboratory methanogenic communities. An invading community was equally successful at establishing itself in a resident community regardless of propagule pressure, which varied between 0.01 and 10% of the size resident community. Invasion resulted in enhanced biogas production (to the level of the pure invading community) but only when propagule pressure was 1% or greater. This inconsistency between invasion success and changes in function can be explained by a lower richness of invading taxa at lower propagule pressures, and an important functional role of the taxa that were absent. Our results highlight that whole community invasion ecology cannot simply be extrapolated from our understanding of single species invasions. Moreover, we show that methane production can be enhanced by invading poorly performing reactors with a better performing community at levels that may be practical in industrial settings.

Highlights

Plant and animal invaders can play a major role in the structure and function of natural ecosystems (Montoya et al, 2006; O’Dowd et al, 2003; Wardle et al, 2011)
Invasion resulted in enhanced biogas production but only when propagule pressure was 1% or greater
This inconsistency between invasion success and changes in function can be explained by a lower richness of invading taxa at lower propagule pressures, and an important functional role of the taxa that were absent

Summary

Introduction

Plant and animal invaders can play a major role in the structure and function of natural ecosystems (Montoya et al, 2006; O’Dowd et al, 2003; Wardle et al, 2011). Like those of plants and animals, are geographically structured (DeLong et al, 2006; Martiny et al, 2006; Nemergut et al, 2013; Whitaker et al, 2003), suggesting an important role of microbial invasions in their formation. There are likely major differences between microbial and macrobial invader dynamics. Leaves falling on the ground (Koide et al, 2005), the release of sewage into the rivers (Mansour et al, 2018) and fecal transplants (Gough et al, 2011) are examples of entire microbial assemblies arriving in a new ecosystem

Results

Discussion

Conclusion