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Featured Application: For industrial-scale extinguishment, natural processes such as acoustic wave propagation can be used. As proven, a technology described in the article using modulated and unmodulated waves can be applied to extinguish flames, as well as to control them. The results presented in the article are limited to extinguishing candle flames, but in the long term, this technique can be used to extinguish flames (especially firebreaks) from various materials (Classes C and B). This inexpensive, versatile, and environmentally safe method can provide a supporting or additional means of fire protection, especially useful in the first stage of fire occurrence. This technique appears to be environmentally friendly (it does not leave stains and does not emit chemicals). Moreover, acoustic waves can be applied to reduce the intensity of smoke and harmful substances in the ambient air, the presence of which is the result of fires (future plans). Due to the consequences of fires, new and environmentally friendly firefighting techniques are constantly being sought. There are many methods of extinguishing flames around the world. One of them is a technique that uses acoustic waves for extinguishing, which can be seen as repeated sequences of molecular compression and dilation (acoustic waves transfer energy due to the movements of molecules and atoms). This research shows a new approach to the extinguishing of flames. In practice, the extinguishing capabilities of low-frequency modulated and unmodulated acoustic waves were tested on a laboratory station, the main component of which was a high-powered acoustic extinguisher (the nominal power was equal to 1700 W). A B&C 21DS115 woofer was applied as a sound source. A Rigol DG4102 and a Proel HPX2800 were used as an acoustic generator with a modulator and as a power amplifier, respectively. In this paper, the presented results are limited to extinguishing candle flames. The tests made it clear that flames can be extinguished using properly generated and directed acoustic waves. As the results indicate, it becomes possible to effectively extinguish flames with both low-frequency modulated and unmodulated acoustic waves, which brings many benefits. [ABSTRACT FROM AUTHOR]

Due to the consequences of fires, new and environmentally friendly firefighting techniques are constantly being sought. There are many methods of extinguishing flames around the world. One of them is a technique that uses acoustic waves for extinguishing, which can be seen as repeated sequences of molecular compression and dilation (acoustic waves transfer energy due to the movements of molecules and atoms). This research shows a new approach to the extinguishing of flames. In practice, the extinguishing capabilities of low-frequency modulated and unmodulated acoustic waves were tested on a laboratory station, the main component of which was a high-powered acoustic extinguisher (the nominal power was equal to 1700 W). A B&C 21DS115 woofer was applied as a sound source. A Rigol DG4102 and a Proel HPX2800 were used as an acoustic generator with a modulator and as a power amplifier, respectively. In this paper, the presented results are limited to extinguishing candle flames. The tests made it clear that flames can be extinguished using properly generated and directed acoustic waves. As the results indicate, it becomes possible to effectively extinguish flames with both low-frequency modulated and unmodulated acoustic waves, which brings many benefits.

The goal of decreasing wildfire hazard as much as possible, using minimal fuel treatments, has led to increasing scholarly interest in fuel reduction spatial optimisation. Most models in the field rest on the assumption of a known wind direction and a corresponding dominant direction of fire spread, and plan firebreaks in perpendicular directions. This strategy is effective when the wind blows in the hypothesised direction, but is quite ineffective when the wind direction is parallel to the firebreaks. In this article, we re-examine this assumption using a global fire dataset covering more than a decade. We perform a variety of circular statistical analyses including circular variance and principal component analysis (PCA). We find that the direction of fire spread in most regions is not limited to a single direction. We also find that the wind direction during fire weather is characterised by a high variance in a substantial fraction of regions around the globe. We validate this finding with a dataset comprised of over a hundred meteorological stations in Israel. We conclude that forest management should consider regional historical data of wind directions and fire spread directions, but also should plan firebreaks so that they are effective in various fire scenarios. [ABSTRACT FROM AUTHOR]

Firebreaks are linear strips that dissect the landscape and prevent or mitigate the spread of wildfires in Mediterranean landscapes. However, few studies have addressed their potential effect on insect behavior. The lack of traffic and other human activities in firebreaks makes them suitable for testing the sole effect of physical habitat disruption on animal movement. Our main objective was to evaluate whether the pattern of movement by a butterfly species was affected by this landscape element. We reconstructed flight trajectories of the lycaenid butterfly Plebejus argus within and around one firebreak using visual and GPS tracking in Doñana National Park (southern Spain). Butterflies that were active at the firebreak boundary often refused to enter the firebreak and, when they did, most individuals returned before reaching the opposite side. Inside the firebreak we recorded faster and straighter trajectories than in adjacent scrubland areas. Butterflies that crossed the firebreak headed the most favorable direction to minimize the time spent within the habitat discontinuity. At the landscape scale, firebreak density increased in areas where P. argus habitat was more fragmented and had lower quality. A narrow, open linear element lacking any human activity induces a marked change in the movement behavior of a butterfly species, with potential consequences on population dynamics at the landscape scale. Therefore, firebreaks used for protecting Mediterranean landscapes could have side effects on animal populations other than localized habitat loss due to mere vegetation removal. [ABSTRACT FROM AUTHOR]

Large lakes can act as firebreaks resulting in distinct patterns in the forest mosaic. Although this is well acknowledged, much less is known about how wildfire is affected by different landscape measures of water and their interactions. Here we examine how these factors relate to historic patterns of wildfire over a 35-year period (1980-2014) for the boreal forest of Saskatchewan, Canada. This includes the amount of water in different-sized neighborhoods, the presence of islands, and the direction, distance, and shape of nearest lake of different sizes. All individual factors affected wildfire presence, with lake sizes ⩾5000 ha and amount of water within a 1000-ha surrounding area the most supported spatial scales. Overall, wildfires were two-times less likely on islands, more likely further from lakes that were circular in shape, and in areas with less surrounding water. Interactive effects were common, including the effect of direction to lake as a function of distance from lakeshore and amount of surrounding water. Our results point to a strong, but complex, bottom-up control of local wildfire activity based on the configuration of natural firebreaks. In fact, fire rotation periods predicted for one area varied more than 15-fold (<47 to >700 years) depending on local patterns in lakes. Old-growth forests within this fire-prone ecosystem are therefore likely to depend on the surrounding configuration of larger lakes. [ABSTRACT FROM AUTHOR]

The effect of transforming natural habitat to commercial land uses can be mitigated by implementing ecological networks (ENs) in production landscapes. However, EN ability to conserve biodiversity is potentially influenced by past and present disturbances, and spatial configuration of habitat patches. Here, we investigated how plant assemblages of a subtropical EN in a timber production landscape in South Africa respond to disturbance history (i.e. natural vs. recovering after removal of Pinus spp.), mowing in firebreaks (i.e. 30 m wide grassy strips intended to stop spread of fires in plantations), and three design parameters: corridor width, distance to protected area boundary, and context i.e. proportion eucalypt compartments within 500 m radius. Reference sites were in the adjacent iSimangaliso Wetland Park, a protected area (PA). Past disturbances and the current practice of mowing in firebreaks significantly influenced plant species composition, but not plant species richness. Plant dominance was greatest in mowed firebreaks, but similar between natural and recovering grassland. None of the design variables affected plant species richness, or composition. However, dominance was significantly and negatively correlated with corridor width, and positively correlated with context. Hence, sites are ordered in terms of their biodiversity value from greatest to lowest: natural areas > recovering areas > firebreaks. Based on these results, natural grassland in wide, well-connected corridors should have greatest conservation priority. We recommend that past disturbances, and current management practices should be taken into account and integrated into the design of future ENs. Such an approach is necessary for effective biodiversity conservation in production landscapes. [ABSTRACT FROM AUTHOR]

ABSTRACT Understanding fire regime dynamics is central to predicting forest structure and the compositional dynamics of boreal forests. Spatial and temporal variations in fire frequency in central Canadian boreal forests over the last 10 000 years were examined to evaluate the influence of bottom-up controls on the regional fire regime. We analysed macroscopic charcoal larger than 160 μm from sediment cores from six lakes to reconstruct fire history and performed GIS analysis of regional landscape features to investigate how fire frequency has changed temporally and how non-climatic factors may have affected long-term fire frequency. Our generalized linear mixed model revealed that temporal changes in fire return intervals (FRIs) were highly dependent on landscape connectivity as inferred through the abundance of natural firebreaks in the form of open water lakes and wetlands. FRIs did not change significantly among highly connected landscapes throughout the Holocene; in contrast, FRIs were significantly longer among poorly connected landscapes in the early Holocene (10-5 cal ka BP), suggesting that the abundant regional firebreaks limited fire spread. All sites had similar FRIs in the late Holocene. The diminishing influence of firebreaks suggests that the regional climate during the late Holocene has overshadowed the influences of the bottom-up controls on fire activities. [ABSTRACT FROM AUTHOR]

Large lakes can act as firebreaks resulting in distinct patterns in the forest mosaic. Although this is well acknowledged, much less is known about how wildfire is affected by different landscape measures of water and their interactions. Here we examine how these factors relate to historic patterns of wildfire over a 35-year period (1980–2014) for the boreal forest of Saskatchewan, Canada. This includes the amount of water in different-sized neighborhoods, the presence of islands, and the direction, distance, and shape of nearest lake of different sizes. All individual factors affected wildfire presence, with lake sizes ≥5000 ha and amount of water within a 1000-ha surrounding area the most supported spatial scales. Overall, wildfires were two-times less likely on islands, more likely further from lakes that were circular in shape, and in areas with less surrounding water. Interactive effects were common, including the effect of direction to lake as a function of distance from lakeshore and amount of surrounding water. Our results point to a strong, but complex, bottom-up control of local wildfire activity based on the configuration of natural firebreaks. In fact, fire rotation periods predicted for one area varied more than 15-fold (700 years) depending on local patterns in lakes. Old-growth forests within this fire-prone ecosystem are therefore likely to depend on the surrounding configuration of larger lakes.

Ubiquitous linear developments, such as dirt tracks and firebreaks, termed 'soft' linear developments ( SLD), represent weaker landscape modifications than paved roads and highways but still could strongly affect populations and communities. Many animals avoid SLD, but some terrestrial mammals seem to select them for faecal marking. Faeces often contain many viable seeds; therefore, SLD may receive a substantial amount and diversity of seeds, which could have important overlooked consequences for plant recruitment., To evaluate the potential role of SLD as seed attractors, we surveyed transects along SLD verges and along the adjacent scrubland in three patches of Mediterranean scrubland. On each transect, we collected ungulate, carnivore and rabbit faeces during two fruiting seasons (2009 and 2010). We quantified all seeds from fleshy-fruit shrubs within faeces and compared their abundance and diversity at SLD verges vs. adjacent scrubland., The frequency of defecation along SLD varied greatly among dispersers, but ungulates avoided SLD for defecation, and carnivores and rabbits positively selected them. Seed prevalence was higher in faeces of carnivores, and seed damage low compared with faeces of rabbits and especially ungulates., The role of SLD as seed attractors was species-dependent. We found from 2·7 to 124 times more viable seeds of carnivore- and rabbit-dispersed plants along SLD than in the scrubland, while ungulate-dispersed plants were more abundant in the scrubland. Of 13 mammal-dispersed shrubs, 4 species were exclusively found along SLD verges, two were found only in the scrubland, and seven were found in both habitats., Synthesis and applications. By promoting mammal-mediated seed dispersal, soft linear developments ( SLD) may act as seed corridors. Given the extremely high density of SLD world-wide, SLD hold a significant overlooked role for management and plant conservation actions. Dispersers selecting SLD can promote roadside restoration, potentially saving financial resources. These feasible benefits must be weighed up against potential spread of alien or undesirable plant species, but we demonstrate the SLD represent a valuable management tool. [ABSTRACT FROM AUTHOR]

While the area of plantation forests continues to increase worldwide, their contribution to the conservation of biodiversity is still controversial. There is a particular concern on the central role played by natural habitat remnants embedded within the plantation matrix in conserving species-rich insect communities. We surveyed butterflies in maritime pine plantation landscapes in south-western France in 83 plots belonging to seven habitat types (five successional stages of pine stands, native deciduous woodlands and herbaceous firebreaks). The effect of plot, habitat and landscape attributes on butterfly species richness, community composition and individual species were analysed with a General Linear Model (GLM), partial Canonical Correspondence Analysis (CCA) and the IndVal method. The most important factors determining butterfly diversity and community composition were the presence of semi-natural habitats (deciduous woodlands and Wrebreaks) at the landscape scale and the composition of understorey vegetation at the plot scale. Pure effects of plot variables explained the largest part of community variation (12.8%), but landscape factors explained an additional, independent part (6.7%). Firebreaks were characterized by a higher species richness and both Wrebreaks and deciduous woodlands harboured species not or rarely found in pine stands. Despite the forest-dominated landscape, typical forest butterflies were rare and mainly found in the deciduous woodlands. Threatened species, such as Coenonympha oedippus and Euphydryas aurinia, were found in pine stands and in firebreaks, but were more abundant in the latter. In the studied plantation forest, the conservation of butterflies depends mainly on the preservation of semi-natural habitats, an adequate understorey management and the maintenance of soil moisture levels. [ABSTRACT FROM AUTHOR]

Abstract Cross-ribbed rolling is a technique routinely used to construct firebreaks along the margins and access tracks of Ngarkat Conservation Park, South Australia. These breaks, approximately 20 m wide, contain regenerating heath communities with an overstorey of mallee. The effects of cross-ribbed rolling on community composition and succession were examined in a single fire patch on the western boundary of Ngarkat Conservation Park across 12 sites located in vegetation burnt approximately 35 years ago. Two areas at each site were investigated, one on rolled communities and the other running parallel on the adjacent unrolled vegetation. There was also a difference in the rolled communities sampled; six were on a 3-year-old break, whereas the remainder were on a 5-year-old break. Results indicate no changes to species richness or diversity when comparing rolled and unrolled areas, but there was some alteration to species composition in rolled communities. These results suggest that under current rolling regimes, the main effect is a reduction in biomass and some accompanying alteration to species composition, but not a reduction in overall species diversity or an increase in weeds. [ABSTRACT FROM AUTHOR]

Forests provide a number of ecological and hydrological services, for instance, contributing to decreased water and sediment yields through increased infiltration and reduced soil erosion. However, forest fires can turn positive forest services into drawbacks, enhancing surface runoff and soil erosion and damaging both hillslopes and downstream aquatic life in rivers. Therefore, appropriate mitigation strategies should be developed to limit these negative effects. Using a runoff and erosion model (the WaterSed model), we proposed forest fire and firebreak scenarios to analyse their respective effects on sediment loads. The model reproduced the measured discharge and sediment loads over an entire hydrological year, including 21 flood events occurring from November 2010 to May 2011 in a 72-km2 Mediterranean catchment (Celone catchment, Puglia, Italy). Eight different forest fire scenarios were then proposed. While the mean burnt areas remained below 2% of the total catchment area, forest fires significantly affected the sediment yield. Indeed, the sediment yield increased over the different forest fire scenarios, from 1.97 to 2.70 t ha−1.yr−1, corresponding to a 37% increase. At the flood-event scale, the sediment load after fire represented up to 324% of the unburnt catchment sediment load in the worst-case scenario. By using realistic firebreaks, the sediment load could be dramatically reduced, from 324% to 165%, in the worst-case scenario. Because rural catchments, such as the Celone catchment, are currently experiencing land abandonment, forested areas are expected to replace crops and expand in the future. This change will likely increase forest ecological services, which may, however, be punctually balanced by negative fire effects. More studies addressing the global impacts of forest growth, fires and firebreaks on sediment transfers are therefore needed in similar environments. • A runoff and erosion model was calibrated against 21 measured storm events. • Forest fire and firebreak effects on sediment loads were evaluated. • Burnt areas controlled the increase in sediment loads after fires. • Burnt area locations were of second order in controlling sediment load increases. • Using existing catchment roads as firebreaks significantly reduced fire effects on sediment loads. [ABSTRACT FROM AUTHOR]

Major drainage basins within the Angeles National Forest in southern California USA are aggregated into zones of homogeneous wildland fire damage-potential using multivariate statistical techniques. Mathematical models are utilized to examine the policy implications of ongoing and projected fuel management strategies in different Forest zones based on simulated impacts of fuelbreak construction and maintenance upon two proxies for future damage-potential: the expected area burned and an index of relative value used by Forest planners. Alternative strategies for future fuelbreak investments are evaluated based on model outcomes. [ABSTRACT FROM AUTHOR]