Revisiting life strategy concepts in environmental microbial ecology

Area of Science:

• Microbial ecology
• Environmental microbiology
• Population dynamics

Background:

• Microorganisms exhibit diverse physiological and genomic traits influencing their life strategies, prevalence, and distribution.
• Classifying microorganisms based on functional traits is challenging due to their metabolic versatility, unlike in animal and plant ecology.
• Previous reviews focused on microbial life strategies using pure cultures, but environmental application is limited by the vast number of uncultured microbes.

Purpose of the Study:

• To review the application of microbial life strategy concepts (copiotrophic-oligotrophic and competitor-stress tolerator-ruderals) in complex microbial communities.
• To assess how environmental cues, such as resource availability, are used to infer microbial life strategies in situ.
• To identify inconsistencies and limitations in current approaches to studying microbial life strategies in environmental settings.

Main Methods:

• Literature review focusing on studies applying microbial life strategy concepts to complex communities.
• Analysis of observational studies linking microbial community responses to abiotic factors (e.g., resource availability).
• Inclusion of bacterial and fungal communities, with a primary focus on bacteria.

Main Results:

• Inconsistent community responses were observed for proposed copiotrophic- and oligotrophic-associated microorganisms at the phyla level.
• Tracking microbial communities at finer phylogenetic resolutions (e.g., family level) may improve the capture of community responses.
• Edaphic factors appear to exert a significant influence on microbial community responses to environmental changes.

Conclusions:

• Current microbial life strategy frameworks show limitations when applied to complex environmental communities.
• Finer taxonomic resolution and consideration of edaphic factors are recommended for future research on microbial life strategies.
• Further empirical evidence is needed to robustly associate specific life strategies with microorganisms in their natural habitats.