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Tropical ecosystems store over half of the world’s aboveground live carbon as biomass, and water availability plays a key role in its distribution. Although precipitation and temperature are shifting across the tropics, their effect on biomass and carbon storage remains uncertain. Here we use empirical relationships between climate and aboveground biomass content to show that the contraction of humid regions, and expansion of those with intense dry periods, results in substantial carbon loss from the neotropics. Under a low emission scenario (Representative Concentration Pathway 4.5) this could cause a net reduction of aboveground live carbon of ~14.4–23.9 PgC (6.8–12%) from 1950–2100. Under a high emissions scenario (Representative Concentration Pathway 8.5) net carbon losses could double across the tropics, to ~28.2–39.7 PgC (13.3–20.1%). The contraction of humid regions in South America accounts for ~40% of this change. Climate mitigation strategies could prevent half of the carbon losses and help maintain the natural tropical net carbon sink.
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Climate Change Impact on Human-Rodent Interfaces: Modeling Junin Virus Reservoir Shifts
Abstract The drylands vesper mouse (Calomys musculinus)is the primary host forJunin mammarenavirus(JUNV), the etiological agent of Argentine hemorrhagic fever in humans. We assessed the potential distribution ofC. musculinusand identified disease transmission hotspots under current climatic conditions and projected future scenarios, including severe (Representative Concentration Pathway 8.5) and intermediate (Representative Concentration Pathway 4.5) climate change scenarios in 2050 and 2070. Utilizing tree-based machine learning algorithms, we modeledC. musculinusdistribution by incorporating bioclimatic and landscape predictors. The model showed strong performance, achievingF-scores between 80.22 and 83.09%. Key predictors indicated thatC. musculinusprefers warm temperatures, moderate annual precipitation, low precipitation variability, and low pasture coverage. Under the severe climate change scenario, suitable areas for the rodent and hotspots for potential disease decreased. The intermediate scenario showed an expansion inC. musculinusdistribution alongside increased potential hotspot zones. Despite the complexity of ecological systems and the limitations of the model, our findings offer a framework for preventive measures and ecological studies in regions prone to the expansion ofC. musculinusand in hotspots for disease transmission driven by climate change.
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- Award ID(s):
- 2325267
- PAR ID:
- 10613575
- Publisher / Repository:
- Springer
- Date Published:
- Journal Name:
- EcoHealth
- ISSN:
- 1612-9210
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1007/s10393-025-01723-z
