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Escalating wildfire activity in the western United States has accelerated adverse societal impacts. Observed increases in wildfire severity and impacts to communities have diverse anthropogenic causes—including the legacy of fire suppression policies, increased development in high-risk zones, and aridification by a warming climate. However, the intentional use of fire as a vegetation management tool, known as “prescribed fire,” can reduce the risk of destructive fires and restore ecosystem resilience. Prescribed fire implementation is subject to multiple constraints, including the number of days characterized by weather and vegetation conditions conducive to achieving desired outcomes. Here, we quantify observed and projected trends in the frequency and seasonality of western United States prescribed fire days. We find that while ~2 C of global warming by 2060 will reduce such days overall (−17%), particularly during spring (−25%) and summer (−31%), winter (+4%) may increasingly emerge as a comparatively favorable window for prescribed fire especially in northern states.
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Vegetation and Peat Soil Characteristics of a Fire-Impacted Tropical Peatland in Costa Rica
Tropical peatlands are highly vulnerable to anthropogenic alterations. In Costa Rica, riverine peatlands are understudied, and most are not included in protected areas. This study aims to generating information useful to assess the anthropogenic pressure in a riverine peatland in Los Robles Sector (LRS) of Medio Queso Wetland (MQW) complex. Evaluations of impacts of fires on vegetation and surface peat chemistry, and the post-2021 fire, makeup of dominant vegetation changes with the Cyperaceae species Scleria melaleuca replacing Eleocharis interstincta as the dominant species are presented. The topsoil (0–20 cm) total C content was quantified as lower than 300 g kg−1 with no significant statistical differences in total C and N content between soil shortly after the fires or two years later. The species E. interstincta is observed to promote higher C stability during the dry season, and has a more recalcitrant composition of the root system compared to the post 2021-fire dominant S. melaleuca. To reduce the impact on C accumulation, measures to prevent grazing-originated fires, especially when the water table is low, are urgent. Hence, this work aims at proving information that can be a baseline for impacts assessment and to inform conservation measures and policies.
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- Award ID(s):
- 1749252
- PAR ID:
- 10635128
- Publisher / Repository:
- Springer
- Date Published:
- Journal Name:
- Wetlands
- Volume:
- 44
- Issue:
- 4
- ISSN:
- 0277-5212
- 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/10.1007/s13157-024-01797-5
