The impact of prescribed fire versus wildfire on the immune and cardiovascular systems of children

Abstract Efforts to restore longleaf pine (Pinus palustris Mill.) in the southeastern US require substantial artificial regeneration. Once established, important questions remain about when to introduce fire. We investigated the impact of initial planting density on tree branching and how prescribed fire might interact with tree architecture and survival. A particular focus was on how prescribed fires could “prune” lower branches. Lower density plantings (897 trees ha−1) had more and larger live lower branches than higher density plantings (2,243 trees ha−1). Fire was effective in pruning lower branches regardless of season burned, but fire in the growing season was more effective at pruning. Branches up to a height of 1.5 to 2 m were killed by fire. Fire applied in August caused greater damage with more needles scorched and/or consumed and more stem char. Prescribed fire did not impact longleaf pine tree survival. In general, fire applied to longleaf pine facilitated pruning lower branches that affect long-term wood quality, an additional argument for its utility in restoration and management of these ecosystems.

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The Impact of Prescribed Fire on Moth Assemblages in the Boston Mountains and Ozark Highlands, in Arkansas

Journal of the Arkansas Academy of Science ◽

10.54119/jaas.2019.7309 ◽

2019 ◽

Vol 73 ◽

Author(s):

Erin E Guerra ◽

Cristina Blanco ◽

Jorista Garrie

Keyword(s):

Prescribed Fire ◽

Ozark Highlands ◽

The Impact

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Effect of fire and thinning on fine-scale genetic structure and gene flow in fire-suppressed populations of sugar pine (Pinus lambertiana Douglas)

10.1101/448522 ◽

2018 ◽

Author(s):

Brandon M. Lind ◽

Malcolm P. North ◽

Patricia E. Maloney ◽

Andrew J. Eckert

Keyword(s):

Gene Flow ◽

Genetic Structure ◽

Sierra Nevada ◽

Prescribed Fire ◽

Management Practices ◽

Fine Scale ◽

Pinus Lambertiana ◽

Sugar Pine ◽

The Impact ◽

Pine Species

AbstractHistorically, frequent, low-severity fires in dry western North American forests were a major driver of ecological patterns and processes, creating resilient ecosystems dominated by widely-spaced pine species. However, a century of fire-suppression has caused overcrowding, altering forest composition to shade-tolerant species, while increasing competition and leaving trees stressed and susceptible to pathogens, insects, and high-severity fire. Exacerbating the issue, fire incidence is expected to increase with changing climate, while fire season has been observed to begin earlier and last longer than historic trends. Forest thinning and prescribed fire have been identified as important management tools to mitigate these risks. Yet little is known of how thinning, fire, or their interaction affect contemporary evolutionary processes of constituent pine species that influence fitness and play an important role in the opportunity for selection and population persistence. We assessed the impact of widely used fuel reduction treatments and prescribed fire on fine-scale gene flow on an ecologically important and historically dominant shade-intolerant pine species of the Sierra Nevada, Pinus lambertiana Dougl. Treatment prescription (no-thin-no-fire, thin-no-fire, and fire-and-thin) was found to differentially affect both fine-scale spatial and genetic structure as well as effective gene flow in this species. Specifically, the thin-no-fire prescription increases genetic structure (spatial autocorrelation of relatives) between adults and seedlings, while seed and pollen dispersal increase and decrease, respectively, as a function of increasing disturbance intensity. While these results may be specific to the stands at our study site, they indicate how assumptions relating to genetic effects based on spatial structure can be misleading. It is likely that these disequilibrated systems will continue to evolve on unknown evolutionary trajectories. The long-term impacts of management practices on reduced fitness from inbreeding depression should be continually monitored to ensure resilience to increasingly frequent and severe fire, drought, and pest stresses.

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Bird diversity increases after patchy prescribed fire: implications from a before–after control–impact study

International Journal of Wildland Fire ◽

10.1071/wf14123 ◽

2015 ◽

Vol 24 (5) ◽

pp. 690 ◽

Cited By ~ 15

Author(s):

Holly Sitters ◽

Julian Di Stefano ◽

Fiona J. Christie ◽

Paul Sunnucks ◽

Alan York

Keyword(s):

Prescribed Fire ◽

Mixed Models ◽

Prescribed Burning ◽

Experimental Studies ◽

Bird Diversity ◽

Eucalypt Forest ◽

Impact Experiment ◽

Impact Area ◽

The Impact ◽

Topographic Variation

Increasingly, patchy prescribed fire of low severity is used by land managers to mitigate wildfire risk, but there are relatively few experimental studies on the effects of low-severity fire on fauna. We used a before–after control–impact experiment to examine avian responses to prescribed fire at two scales in topographically variable, tall-open eucalypt forest in south-east Australia. We surveyed birds at control and impact areas twice before and twice after fire, and applied mixed models to investigate responses of avian turnover, richness and the occurrence of selected species. Approximately half of the impact area was burnt and topographic variation generated a finger-like configuration of burnt patches on ridges and unburnt patches in gullies. Our findings at the smaller scale (0.8 ha) indicated that the fire resulted in increased bird diversity because a patchwork of burnt and unburnt areas provided a mosaic of distinct successional states in which different species occurred. Additionally, we found that the effect of fire on species richness and occurrence was a function of the presence of unburnt topographic refuges. In contrast, we found no compelling evidence to suggest that birds responded to the fire at the larger scale (400 ha). We conclude that application of low-severity fire in a patchy manner enhanced avian diversity and facilitated the persistence of the birds detected in pre-fire surveys. Although the levels of patchiness required to sustain diverse taxa warrant further study, our findings highlight the importance of formally incorporating patchiness into prescribed burning for the ecologically sensitive management of contemporary landscapes.

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Populus forest characterization in Elk Island National Park relative to herbivory, prescribed fire, and topography

Canadian Journal of Botany ◽

10.1139/b97-866 ◽

1997 ◽

Vol 75 (9) ◽

pp. 1518-1526 ◽

Cited By ~ 12

Author(s):

Edward W. Bork ◽

Robert J. Hudson ◽

Arthur W. Bailey

Keyword(s):

Plant Community ◽

Prescribed Fire ◽

National Park ◽

Prescribed Burning ◽

Net Primary Production ◽

Small Diameter ◽

Basal Area ◽

Ungulate Herbivory ◽

Elk Island National Park ◽

The Impact

Wild ungulate herbivory and prescribed fire can modify the vegetational characteristics of Populus forest plant communities and alter their potential to meet conservation objectives. Effective management of these areas depends on understanding the impact of these disturbances across natural landscapes. Our objective was to quantify various overstory and understory plant community characteristics in the Populus forests in and around Elk Island National Park, Alberta, under different disturbance regimes. Vegetation from 36 sites, stratified by four topographic positions and three historical treatment combinations of fire and native ungulate herbivory, were sampled. In these sites, we quantified tree density, basal area and cover, understory species richness and diversity, shrub density and height, as well as grass, forb, and browse annual net primary production (ANPP). Although tree canopy characteristics were similar under all three disturbances, small-diameter trees (< 5 cm) were nearly absent within the Park. The reference area outside the Park had greater browse-leaf and -twig ANPP, as well as shrub height, but lower grass ANPP. Inside the Park, burned areas had greater shrub density and ANPP of grass and forb components. Topographically, tree stand basal area, cover, and shrub height were greatest on the northern slope, as was browse-leaf ANPP. Species diversity and richness were relatively greater on the toe slope. Within the plant community variables examined, the disturbances and positions frequently interacted, particularly the burned treatment with the crest position and level of herbivory with the south-facing and north-facing slopes. The structure, composition, and ANPP of Populus forest in Elk Island National Park has been significantly affected by both ungulate herbivory and prescribed burning. These factors, along with topography, influence the vegetation and are consequently important for management of the park's habitat and ungulate populations. Key words: ANPP, national park, prescribed fire, structure, topography, ungulate herbivory.

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The Impact of a Prescribed Burn versus a Wildfire on the Immune and Cardiovascular Systems of Children

Journal of Allergy and Clinical Immunology ◽

10.1016/j.jaci.2018.12.250 ◽

2019 ◽

Vol 143 (2) ◽

pp. AB80

Author(s):

Mary Prunicki ◽

Xiaoying Zhou ◽

Kari Nadeau

Keyword(s):

Prescribed Burn ◽

Cardiovascular Systems ◽

The Impact

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Short-term response of the long-nosed bandicoot, Perameles nasuta, and the southern brown bandicoot, Isoodon obesulus obesulus, to low-intensity prescribed fire in heathland vegetation

Wildlife Research ◽

10.1071/wr12110 ◽

2012 ◽

Vol 39 (8) ◽

pp. 731 ◽

Cited By ~ 7

Author(s):

Ben Hope

Keyword(s):

Home Range ◽

Prescribed Fire ◽

Prescribed Burning ◽

Fire Regime ◽

Fire Hazard ◽

Home Ranges ◽

Short Term ◽

Hazard Reduction ◽

Low Intensity ◽

The Impact

Context Prescribed burning is routinely performed within the Sydney Basin as a method of fire-hazard mitigation. Despite the widespread use of prescribed fire, knowledge of the impact of prescribed fire on most fauna species remains unclear. This is particularly the case for bandicoot species. Aims To determine the impact of a low-intensity prescribed fire on the survival of the long-nosed bandicoot, Perameles nasuta, and the southern brown bandicoot, Isoodon obesulus obesulus (hereafter abbreviated to I. obesulus), immediately after the fire and at 5 weeks, 5 months and 13 months following the fire. To document the spatial ecology and nesting requirements of I. obesulus and P. nasuta before and after fire. Methods One I. obesulus and seven P. nasuta (five female and two male) individuals were radio-tracked. Animals were tracked before, during and following a hazard-reduction burn to assess the impact of fire on home range, survival and nesting behaviour. Key results Post-fire survival of P. nasuta and I. obesulus was high and the population remained stable up to 5 months following the fire. All animals tracked within the burn area (three female P. nasuta) survived the passage of fire. The home range for one male I. obesulus was found to be 2.35 ha 50% kernel-density estimate (KDE) and 12.35 ha 95% KDE. Female P. nasuta (n = 5) had a home range of 1.3 ha ± 0.2 s.e. 50% KDE and 7.5 ha ± 1.7 s.e. 95% KDE. Male P. nasuta (n = 1) had a home range of 1.1 ha 50% KDE and 6.5ha 95% KDE. Nesting for both species tended to occur in dense vegetation, with a slight shift to non-combustible refuge sites post-fire. Animals tended to maintain exclusive and relatively stable core home ranges, although overlap of non-core home ranges was common. Conclusions The survival of bandicoots following a low-intensity hazard-reduction fire was high in the short term; however, further research is required to determine how the components of a fire regime affect native species, in particular peramelids. Implications Hazard-reduction fires should be used with caution to manage the isolated and endangered northern Sydney population of I. obesulus, so as to ensure the persistence of this species.

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Investigating the links between ozone and organic aerosol chemistry in a biomass burning plume from a prescribed fire in California chaparral

Atmospheric Chemistry and Physics ◽

10.5194/acp-15-6667-2015 ◽

2015 ◽

Vol 15 (12) ◽

pp. 6667-6688 ◽

Cited By ~ 42

Author(s):

M. J. Alvarado ◽

C. R. Lonsdale ◽

R. J. Yokelson ◽

S. K. Akagi ◽

H. Coe ◽

...

Keyword(s):

Organic Compounds ◽

Biomass Burning ◽

Prescribed Fire ◽

Organic Aerosol ◽

Basis Set ◽

Atmospheric Composition ◽

Organic Nitrate ◽

Peroxy Radicals ◽

Smoke Plume ◽

The Impact

Abstract. Within minutes after emission, complex photochemistry in biomass burning smoke plumes can cause large changes in the concentrations of ozone (O3) and organic aerosol (OA). Being able to understand and simulate this rapid chemical evolution under a wide variety of conditions is a critical part of forecasting the impact of these fires on air quality, atmospheric composition, and climate. Here we use version 2.1 of the Aerosol Simulation Program (ASP) to simulate the evolution of O3 and secondary organic aerosol (SOA) within a young biomass burning smoke plume from the Williams prescribed fire in chaparral, which was sampled over California in November 2009. We demonstrate the use of a method for simultaneously accounting for the impact of the unidentified intermediate volatility, semi-volatile, and extremely low volatility organic compounds (here collectively called "SVOCs") on the formation of OA (using the Volatility Basis Set – VBS) and O3 (using the concept of mechanistic reactivity). We show that this method can successfully simulate the observations of O3, OA, NOx, ethylene (C2H4), and OH to within measurement uncertainty using reasonable assumptions about the average chemistry of the unidentified SVOCs. These assumptions were (1) a reaction rate constant with OH of ~ 10-11 cm3 s−1; (2) a significant fraction (up to ~ 50 %) of the RO2 + NO reaction resulted in fragmentation, rather than functionalization, of the parent SVOC; (3) ~ 1.1 molecules of O3 were formed for every molecule of SVOC that reacted; (4) ~ 60 % of the OH that reacted with the unidentified non-methane organic compounds (NMOC) was regenerated as HO2; and (5) that ~ 50 % of the NO that reacted with the SVOC peroxy radicals was lost, presumably to organic nitrate formation. Additional evidence for the fragmentation pathway is provided by the observed rate of formation of acetic acid (CH3COOH), which is consistent with our assumed fragmentation rate. However, the model overestimates peroxyacetyl nitrate (PAN) formation downwind by about 50 %, suggesting the need for further refinements to the chemistry. This method could provide a way for classifying different smoke plume observations in terms of the average chemistry of their SVOCs, and could be used to study how the chemistry of these compounds (and the O3 and OA they form) varies between plumes.

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