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Because ecosystems are complex, ecological drought definitions currently are more conceptual than operational (e.g., “an episodic deficit in water availability that drives ecosystems beyond thresholds of vulnerability, impacts ecosystem services, and triggers feedbacks in natural and/or human systems”). Identification of drought and drought characteristics depends on the drought definition and metric being sought.
This study presents a generalizable functional diversity approach for measuring pyrodiversity, which incorporates multiple fire regime traits and can be applied across scales. Further, we tested the socioecological drivers of pyrodiversity among forests of the western United States. Largely mediated by burn activity, pyrodiversity was positively associated with actual evapotranspiration, climate water deficit, wilderness designation, elevation and topographic roughness but negatively with human population density. These results indicate pyrodiversity is highest in productive areas with pronounced annual dry periods and minimal fire suppression. This work can facilitate future pyrodiversity studies including whether and how it begets biodiversity among taxa, regions and fire regimes.
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The Pack Creek Wildfire, ignited by an abandoned campfire, started early in the fire season on June 9, 2021 in the Pack Creek Day Use Area on the Manti-La Sal National Forest.
Under the influence of down-slope, down-canyon winds, the fire made a push west and down Pack Creek. The fire quickly exploded as a crown fire through a riparian area composed largely of cottonwood trees and pinyon and juniper landscapes. Within the community, fuel breaks implemented by Forestry, Fire and State Lands (State of Utah, FFSL) were designed to act as intermittent catch points for firefighters to actively engage the fire.
This study found that prescribed fires and operations reduced tree basal area loss from the wildfire by an average of 32% and 22% respectively, and that severity was reduced by 72% in areas with both prescribed fire and operations. Our approach could be applied to other wildfires and regions to better understand the effects of fuel treatments and fire suppression operations on wildfire severity.
Across practice types, ≥99% of fields had no evidence of rills, gullies, or pedestaling from erosion, and 91% of fields had <20% bare soil cover, with region being the strongest predictor of bare soil cover. Seventy-nine percent of fields had ≥50% grass cover, with cover differing by practice type and region. Native grass species were present on more fields in wildlife and wetland practices compared to grassland practices. Forb cover >50% and native forb presence occurred most frequently in wildlife practices, with region being the strongest driver of differences. Federally listed noxious grass and forb species occurred on 23% and 61% of fields, respectively, but tended to constitute a small portion of cover in the field. Estimates from edge-of-field surveys and in-field validation sampling were strongly correlated, demonstrating the utility of the edge-of-field surveys. Our results provide the first national-level assessment of CRP establishment in three decades, confirming that enrolled wildlife and wetland practices often have diverse perennial vegetation cover and very few erosional features.
- Automated and repeatable method to improve scientific integrity of long-term data
- Analyzed long-term data to improve monitoring policies and efforts
- Increased collaborations between federal and state agencies to improve data quality
- Recommendations for managing existing and new long-term monitoring data
- Spatiotemporal heatmap video of Greater sage-grouse counts across North American
To address the challenge of spatial conservation prioritization, we developed the Prioritizing Restoration of Sagebrush Ecosystems Tool (PReSET). This decision support tool utilizes the prioritizr package in program R and an integer linear programming algorithm to select parcels representing both high biodiversity value and high probability of restoration success. We tested PReSET on a sagebrush steppe system within southwestern Wyoming using distributional data for six species with diverse life histories and a spatial layer of predicted sagebrush recovery times to identify restoration targets at both broad and local scales. While the broad-scale portion of our tool outputs can inform policy, the local-scale results can be applied directly to on-the-ground restoration. We identified restoration priority areas with greater precision than existing spatial prioritizations and incorporated range differences among species. We noted tradeoffs, including that restoring for habitat connectivity may require restoration actions in areas with lower probability of success. Future applications of PReSET will draw from emerging datasets, including spatially-varying economic costs of restoration, animal movement data, and additional species, to further improve our ability to target effective sagebrush restoration.
Retrospective sensitivity analysis suggested the dynamics in populations growth rates were driven by increases in juvenile, adult, first nest, and yearling survival in the Treatment relative to the Control. These findings demonstrate the effectiveness of targeted conifer removal as a management strategy for conserving sage-grouse populations in sagebrush steppe affected by conifer expansion. Examples of positive, population-level responses to habitat management are exceptionally rare for terrestrial vertebrates, and this study provides promising evidence of active management that can be implemented to aid recovery of an imperiled species and biome.
The fire spread rate within WUI communities is determined for nine wildfires that were ranked among the most destructive wildfires in North America. An improved quasi-empirical model that considers radiation and fire spotting as modes of fire spread inside a community is proposed. The new model is validated using the documented spread rates during the 2007 Witch and Guejito fires and the 2017 Tubbs fire. The proposed model is computationally efficient and can be used to quantify fire spread rate and the number of affected structures inside a community during a wildfire event.
Wildland research, management, and policy in western democracies have long relied on concepts of equilibrium: succession, sustained yield, stable age or species compositions, fire return intervals, and historical range of variability critically depend on equilibrium assumptions. Not surprisingly, these largely static concepts form the basis for societal expectations, dominant management paradigms, and environmental legislation. Knowledge generation has also assumed high levels of stasis, concentrating on correlational patterns with the expectation that these patterns would be reliably transferrable. Changes in climate, the introduction of large numbers of exotic organisms, and anthropogenic land conversion are leading to unprecedented changes in disturbance regimes and landscape composition. Importantly, these changes are largely non-reversable; once introduced exotic species are seldom eradicated, climates will continue to warm for the foreseeable future, and many types of land conversion cannot be easily undone.