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ABSTRACT Fire is a common ecological disturbance that structures terrestrial ecosystems and biological communities. The ability of fires to contribute to ecosystem heterogeneity has been termed pyrodiversity and has been directly linked to biodiversity (i.e., the pyrodiversity–biodiversity hypothesis). Since climate change models predict increases in fire frequency, understanding how fire pyrodiversity influences soil microbes is important for predicting how ecosystems will respond to fire regime changes. Here we tested how fire frequency‐driven changes in burn patterns (i.e., pyrodiversity) influenced soil microbial communities and diversity. We assessed pyrodiversity effects on soil microbes by manipulating fire frequency (annual vs. biennial fires) in a tallgrass prairie restoration and evaluating how changes in burn patterns influenced microbial communities (bacteria and fungi). Annual burns produced more heterogeneous burn patterns (higher pyrodiversity) that were linked to shifts in fungal and bacterial community composition. While fire frequency did not influence microbial (bacteria and fungi) alpha diversity, beta diversity did increase with pyrodiversity. Changes in fungal community composition were not linked to burn patterns, suggesting that pyrodiversity effects on other ecosystem components (e.g., plants and soil characteristics) influenced fungal community dynamics and the greater beta diversity observed in the annually burned plots. Shifts in bacterial community composition were linked to variation in higher severity burn pattern components (grey and white ash), suggesting that thermotolerance contributed to the observed changes in bacterial community composition and lower beta diversity in the biennially burned plots. This demonstrates that fire frequency‐driven increases in pyrodiversity augment biodiversity and may influence productivity in fire‐prone ecosystems.
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The underground network: facilitation in soil bacteria
Our understanding of the fundamental role that soil bacteria play in the structure and functioning of Earth's ecosystems is ever expanding, but insight into the nature of interactions within these bacterial communities remains rudimentary. Bacterial facilitation may enhance the establishment, growth, and succession of eukaryotic biota, elevating the complexity and diversity of the entire soil community and thereby modulating multiple ecosystem functions. Global climate change often alters soil bacterial community composition, which, in turn, impacts other dependent biota. However, the impact of climate change on facilitation within bacterial communities remains poorly understood even though it may have important cascading consequences for entire ecosystems. The wealth of metagenomic data currently being generated gives community ecologists the ability to investigate bacterial facilitation in the natural world and how it affects ecological systems responses to climate change. Here, we review current evidence demonstrating the importance of facilitation in promoting emergent properties such as community diversity, ecosystem functioning, and resilience to climate change in soil bacterial communities. We show that a synthesis is currently missing between the abundant data, newly developed models and a coherent ecological framework that addresses these emergent properties. We highlight that including phylogenetic information, the physicochemical environment, and species‐specific ecologies can improve our ability to infer interactions in natural soil communities. Following these recommendations, studies on bacterial facilitation will be an important piece of the puzzle to understand the consequences of global change on ecological communities and a model to advance our understanding of facilitation in complex communities more generally.
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- Award ID(s):
- 2224760
- PAR ID:
- 10537627
- Publisher / Repository:
- Wiley Online Library
- Date Published:
- Journal Name:
- Oikos
- Volume:
- 2024
- Issue:
- 8
- ISSN:
- 0030-1299
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1111/oik.10299
