Historical Disturbance Patterns Leave Long-Lasting Effects on Microbial Communities
A new experimental study using bacterial communities shows that past disturbance regimes leave persistent legacies that shape how communities respond to new disturbances and invasive species. Researchers exposed bacterial populations to approximately 120 generations of one disturbance regime, then subjected them to novel regimes and invasions for another 120 generations. The findings suggest that ignoring historical disturbance history may explain conflicting results in ecology and complicate predictions about how ecosystems will respond to climate-driven changes.
Researchers using a model bacterial system demonstrated that the history of disturbance a community has experienced continues to influence its composition, function, and vulnerability to invasion long after conditions change. Communities were subjected to disturbance regimes for roughly 120 bacterial generations before being exposed to novel regimes and invasion attempts for an equivalent period. The study found that historical legacies persistently altered disturbance-diversity relationships, and that certain combinations of past and present disturbance regimes either promoted or suppressed successful invasions — sometimes in ways that contradict the general expectation that higher diversity resists invasion. The authors argue this may help reconcile longstanding contradictions in the ecological literature on diversity and invasibility. The work underscores that accurately predicting ecosystem responses to ongoing climate change and human-altered disturbance regimes requires accounting for communities' disturbance histories, not just current conditions.
What's missing
As a preprint posted on bioRxiv, this study has not yet undergone formal peer review, and its findings should be interpreted with that caveat in mind. The study is limited to a bacterial microcosm system, and it remains an open question how well these results scale to more complex, multi-trophic ecosystems or to longer evolutionary timescales. The specific disturbance types, intensities, and bacterial species used are not described in the abstract, limiting assessment of generalizability. The mechanisms driving legacy effects are not fully resolved.
What different sources said
- bioRxivCenter
Disturbance regime changes leave long-lasting legacies on a microbial community's composition and function
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