Microbial biodiversity contributes to soil carbon release: a case study on fire disturbed boreal forests.
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ABSTRACT:
SUBMITTER: Zhou X
PROVIDER: S-EPMC9303362 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:Fire disturbances are becoming more common, more intense, and further-reaching across the globe, with consequences for ecosystem functioning. Importantly, fire can have strong effects on the soil microbiome, including community and functional changes after fire, but surprisingly little is known regarding the role of soil fire legacy in shaping responses to recent fire. To address this gap, we conducted a manipulative field experiment administering fire across 32 soils with varying fire legacies, including combinations of 1-7 historic fires and 1-33 years since most recent fire. We analyzed soil metatranscriptomes, determining for the first time how fire and fire legacy interactively affect metabolically-active soil taxa, the microbial regulation of important carbon (C), nitrogen (N) and phosphorus (P) cycling, expression of carbohydrate-cycling enzyme pathways, and functional gene co-expression networks. Experimental fire strongly downregulated fungal activity while upregulating many bacterial and archaeal phyla. Further, fire decreased soil capacity for microbial C and N cycling and P transport, and drastically rewired functional gene co-expression. Perhaps most importantly, we highlight a novel role of soil fire legacy in regulation of microbial C, N, and P responses to recent fire. We observed a greater number of functional genes responsive to the interactive effects of fire and fire legacy than those affected solely by recent fire, indicating that many functional genes respond to fire only under certain fire legacy contexts. Therefore, without incorporating fire legacy of soils, studies will miss important ways that fire shapes microbial roles in ecosystem functioning. Finally, we showed that fire caused significant downregulation of carbon metabolism and nutrient cycling genes in microbiomes under abnormal soil fire histories, producing a novel warning for the future: human manipulation of fire legacies, either indirectly through global change-induced fire intensification or directly through fire suppression, can negatively impact soil microbiome functional responses to new fires.
2024-08-12 | GSE274211 | GEO
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Project description:Boreal caribou require large areas of undisturbed habitat for persistence. They are listed as threatened with the risk of extinction in Canada because of landscape changes induced by human activities and resource extraction. Here we ask: Can the protection of habitat for boreal caribou help Canada meet its commitments under the United Nations Convention on Biological Diversity and United Nations Framework Convention on Climate Change? We identified hotspots of high conservation value within the distribution of boreal caribou based on: (1) three measures of biodiversity for at risk species (species richness, unique species and taxonomic diversity); (2) climate refugia or areas forecasted to remain unchanged under climate change; and, (3) areas of high soil carbon that could add to Canada's greenhouse gas emissions if released into the atmosphere. We evaluated the overlap among hotspot types and how well hotspots were represented in Canada's protected and conserved areas network. While hotspots are widely distributed across the boreal caribou distribution, with nearly 80% of the area falling within at least one hotspot type, only 3% of the distribution overlaps three or more hotspots. Moreover, the protected and conserved areas network only captures about 10% of all hotspots within the boreal caribou distribution. While the protected and conserved areas network adequately represents hotspots with high numbers of at risk species, areas occupied by unique species, as well as the full spectrum of areas occupied by different taxa, are underrepresented. Climate refugia and soil carbon hotspots also occur at lower percentages than expected. These findings illustrate the potential co-benefits of habitat protection for caribou to biodiversity and ecosystem services and suggest caribou may be a good proxy for future protected areas planning and for developing effective conservation strategies in regional assessments.
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