Trait-based microbial interactions and their influence on ecosystem function intensifies under stress

A major challenge in ecology is to understand how different populations interact to determine ecosystem function, particularly in communities with large numbers of co-occurring populations. We use a trait-based model of microbial litter decomposition (DEMENT) to quantify how different populations impact ecosystem function. DEMENT is a spatially explicit, individual-based process model that specifically highlights the interactions of microbial functional guilds over exo-enzymes. Using such a model, we conduct simulation experiments to build a novel framework that highlights the interplay between population traits and environmental conditions, focusing on their combined influence on community interactions and ecosystem function. Our results suggest that the impact of a population is driven by its resource acquisition traits and the community functional capacity, but that physiological stress amplifies the impact of both positive and negative interactions. Further, net positive impacts on ecosystem function can arise even as populations have negative pairwise interactions with neighboring populations. As communities shift in response to global climate change, our findings reveal the potential to predict the biogeochemical functioning of communities from population traits and interactions.  

Primary Presenter: Brittni Bertolet, University of California Irvine (brittnibertolet@gmail.com)

Authors:

Brittni Bertolet, University of California Irvine  (brittni.bertolet@uci.edu)

Luciana Chavez Rodriguez, University of California Irvine  (lucianac@uci.edu)

José Murúa, University of California Irvine  (jmuruaro@uci.edu)

Alonso Favela, University of Arizona  (alonsof@arizona.edu)

Steven Allison, University of California Irvine  (allisons@uci.edu)