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Assessing post-fire recovery is essential to forecast how ecosystems will respond to future warmer conditions and higher fire severity. Such assessments must consider site conditions and the post-fire recovery of trees and shrubs. We used tree-ring data and intrinsic water-use efficiency (WUEi) to quantify the post-fire responses of a tree (Pinus pinea) and a shrub (Juniperus phoenicea) in Mediterranean coastal dunes located in the Doñana protected area, SW Spain. We compared pines and junipers growing in an inter-dune slack with those growing in a nearby dune ridge. We quantified crown damage and bark char in pines impacted by a wildfire. Pines with lower crown damage after the fire showed a higher growth rate one year later. Growth decreased afterwards in the case of fast-growing pines from the slack site, whereas slow-growing dune pines showed increasing growth rates one to three years after the fire. The fire did not change the pines' WUEi, whereas the junipers located in dunes presented the highest WUEi values. Severe crown damage (damage > 60%) impairs long-term growth recovery in P. pinea. Open and heterogeneous landscapes can reduce the wildfire risk in the study Mediterranean area, where slack vs. dune and tree vs. shrub differences should be considered in post-fire management plans. [ABSTRACT FROM AUTHOR]

Structural lightweight-aggregate concrete (LWAC) has gained a broad range of applications in the construction industry owing to its reduced dead load and enhanced fire resistance. In this study, the potential of using lightweight expanded clay aggregates as a partial replacement for fine and coarse natural aggregates was experimentally and numerically examined. Testing was performed on cylindrical specimens made of normalweight and lightweight concrete incorporating microsilica as a partial replacement for cement to determine the associated stress-strain behavior. Subsequently, three-point bending testing was conducted on reinforced concrete beams to evaluate their structural behavior. Four levels of temperature were considered: 25°C (ambient temperature), and 250, 500, and 750°C (elevated temperatures). The finite element method through Abaqus software was deployed to numerically investigate the behavior at elevated temperatures through a comprehensive parametric study. The experimental and numerical results indicate that under high-temperature exposure, LWAC outperforms its normal counterpart in terms of strength, stiffness, and Young's modulus. It is also noticeable that LWAC beams retained their load-bearing capacity better than normalweightaggregate concrete (NWAC) after reaching the peak load. [ABSTRACT FROM AUTHOR]

In ecosystems where trees and grasses coexist, some grass species are found only in open habitats and others persist under trees. The persistence of shade intolerant grasses in ecosystems such as open woodlands and savannas depends on recurrent fires to open the tree canopy. Therefore, grasses that depend on open sites might benefit from high flammability. We tested if shade intolerant grasses are more flammable than shade tolerant grasses and if flammability differences affected post‐fire grass growth. We examined the relationship between shade tolerance and flammability by determining individual‐level flammability and species shade tolerance of 17 grass species. We also measured grass traits to determine trait effects on flammability and the post‐fire response. Grass species varied in flammability, mainly in the amount of heat produced during burning. Shade tolerant species produced less heat at 50 cm above the ground. Biomass and live fuel moisture had the greatest effects on heat release. However, the negative effect of live fuel moisture on heat release at the soil surface was weakened in plants with high specific leaf area. In addition, grass bulk density negatively influenced heat release at 50 cm height. Heat release at the soil surface negatively influenced post‐fire growth. However, the influences of soil heating and species‐specific traits on individual survival were more complex with 2‐ and 3‐way interactions. Shade tolerance was negatively correlated with a major axis of flammability variation: shade tolerant grasses produced less heat where that heat could damage tree boles. Such heterogeneity in grass flammability may help maintain the tree–grass mixture in natural plant communities. If shade tolerant grasses near trees cause less fire damage to woody plants, especially tree saplings, this may weaken positive grass‐fire feedbacks and thus aid the long‐term coexistence of trees and grasses. [ABSTRACT FROM AUTHOR]

This experimental investigation reveals the projected benefits of concrete-filled double-skin tubular columns. These columns are made up of an outside steel tube, an interior UPVC pipe, and a sandwich of concrete among these tubes. The effect of the dimension ratio of the outer-to-inner tube, the thickness ratio of the outer tube, and the internal tube material (steel/UPVC) on the ultimate compressive strength of double-skin tubular columns samples filled with concrete are investigated. Finally, the experimental findings were compared to previously published design approaches in AISC (2010), GB50936 (2014), and EC4 (2004). The analysis revealed that GB50936 (2014) produces the best outcomes, followed by AISC (2010) and EC4 (2004). In addition, the samples were tested in elevated temperatures to study their post-fire axial capacity. It was discovered that the type of infilled concrete and interior tube material has no major impact on the performance of samples at elevated temperatures.

Assessing post-fire recovery is essential to forecast how ecosystems will respond to future warmer conditions and higher fire severity. Such assessments must consider site conditions and the post-fire recovery of trees and shrubs. We used tree-ring data and intrinsic water-use efficiency (WUEi) to quantify the post-fire responses of a tree (Pinus pinea) and a shrub (Juniperus phoenicea) in Mediterranean coastal dunes located in the Doñana protected area, SW Spain. We compared pines and junipers growing in an inter-dune slack with those growing in a nearby dune ridge. We quantified crown damage and bark char in pines impacted by a wildfire. Pines with lower crown damage after the fire showed a higher growth rate one year later. Growth decreased afterwards in the case of fast-growing pines from the slack site, whereas slow-growing dune pines showed increasing growth rates one to three years after the fire. The fire did not change the pines’ WUEi, whereas the junipers located in dunes presented the highest WUEi values. Severe crown damage (damage > 60%) impairs long-term growth recovery in P. pinea. Open and heterogeneous landscapes can reduce the wildfire risk in the study Mediterranean area, where slack vs. dune and tree vs. shrub differences should be considered in post-fire management plans.

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ABSTRACT Chipmunks ( Tamias spp.) in western North America are important for their numerical abundance, their role in pathogen transmission, and the composition and structure of food webs. As such, land management agencies (e.g., U.S. Forest Service) often conduct field surveys to monitor the diversity and abundance of chipmunk species as a measure of forest health. These small mammal communities often include several morphologically similar chipmunk species, some of which occasionally hybridize, which can make field identification of species difficult. However, species-specific differences in both spatial distribution and habitat use make it imperative that biotic inventories correctly identify chipmunk species. We compared molecular-based and field-based, external phenotypic identifications of 4 chipmunk species in the Lake Tahoe Basin of the Sierra Nevada in California and Nevada, USA. Across all years and sites, we found an error rate of 14% for field-based identifications with significantly lower rates of misidentification in relatively undisturbed wildlands in comparison to recently burned wildlands or urbanized sites. We also found evidence for sporadic hybridization between focal species, including cases of mito-nuclear mismatch. Our study highlights the utility of molecular tools in corroborating field identifications of chipmunks in changing landscapes. © 2016 The Wildlife Society. [ABSTRACT FROM AUTHOR]

• Lightweight and normal weight aggregate reinforced-concrete beams were subjected to ambient and elevated temperatures. • Lightweight aggregate beams demonstrated better seismic performance at high temperatures. • The dissipated energy varied by the concrete type and the heat exposure level. • RC beams incorporating LECA can safely be implemented in structures subjected to seismic loads. • The finite element analysis can accurately simulate the seismic behavior of RC beams after exposure to high temperatures. The stringent demand for designing fire-resistant structures in recent years has triggered a good deal of effort into theoretical and experimental studies. Structures may be exposed to seismic loading after a fire in the course of their lifetime, resulting in the reduction of their integrity. This study examines the seismic performance of damaged light weight aggregate reinforced concrete beams by exposure them to elevated temperatures. Accordingly, a set of 8 light weight and normal weight concrete prisms were cast and tested under quasi-static reversed cyclic loading after exposure to temperatures of 25, 250, 500 and 750 °C. The stress-strain relationship, residual deformations, strength and stiffness degradation, energy dissipation capacity and cracking pattern of light weight beams were compared to those of the normal weight counterparts. The experimental results revealed that the light weight beams, although with lower compressive strength at ambient temperatures, show better seismic performance when exposed to elevated temperatures as compared to their normal weight companions. On this account, the residual deformations of the entire set of beams decreased with increasing the thermal exposure level. However, this was less pronounced in the case of lightweight prisms. In addition, the energy dissipation capacity of normal weight prisms was higher than that of the lightweight beam specimens at ambient temperature. Nonetheless, the dissipated energy in lightweight concrete overtook that of normal weight concrete as the temperature was increased. Moreover, the beams under investigation were numerically modeled in OpenSees through fiber section models in order to verify the obtained experimental results. The fire effect was applied in the compressive strength reduction of the beam specimens based on experimental results, such that each heat-exposure level relatively decreased the compressive strength of prisms. The results confirmed that the numerical responses obtained from material models in OpenSees could provide the characteristics of the beam capacity as well as the strength and stiffness degradation behavior in good accord with the experimental results. [ABSTRACT FROM AUTHOR]

Mediterranean climate ecosystems are characterised by frequent fires, but few studies have focused on the effects of fire disturbance on biological communities in streams in these ecosystems. To compare the responses of macroinvertebrate communities to wildfire, eight sites were established and annually sampled for 5 years. Two months after fire, the number and abundance of macroinvertebrate taxa were not significantly different from those in control streams, but their composition and functional attributes had changed. As expected, an increase in r-strategy taxa was observed during the year following fire. Above all, macroinvertebrate assemblages responded more strongly to hydrology (previous spring precipitation) than to fire. Drought was found to be an overriding disturbance factor, but macroinvertebrate assemblages showed high resilience. In a climate change scenario coupled with human demand for water, it will be important to study the effects of drought interacting with other disturbances like wildfire (which is in turn driven by drought). [ABSTRACT FROM AUTHOR]

This study attempts to understand the effect of the main fire factors (smoke, ash and heat) on the germination of three invasive species widely distributed in many countries: Acacia melanoxylon, Conyza canadensis and Eucalyptus globulus. Fifteen simple treatments were tested: 3 of Smoke, 3 of Ash, 8 of Heat, and 1 Control (Control 1). In addition, in C. canadensis a second test was performed using 4 combined treatments: Smoke-Ash, Smoke-Heat, Ash-Heat, Smoke-Ash-Heat and Control 2.The seeds were incubated in a germination chamber with a photoperiod of 16h of light at 24°C and 8h of darkness at 16°C. Three species showed different responses from fire factors. Smoke and ash treatments did not modify the germination percentage of A. melanoxylon, but moderate heat increased germination and severe heat significantly decreased it. Moreover, some treatments significantly decreased germination rate. C. canadensis germination was increased by moderate levels of all the factors tested, whilst high levels of fire delayed and reduced germination. The combined action of the fire factors did not modify the germination percentage, but did reduce the germination rate. E. globulus had low germination in Control 1 and none of the tested treatments modified either percentage or rate of germination. Finally, regenerative aspects of the three species are discussed. [ABSTRACT FROM AUTHOR]

Significant bushfires occurred around the Great Dividing Range in south eastern Australia in the summers of 2003 and 2006/2007. The combined scale of these bushfires presents important hydrological implications for the region in the coming decades. This paper reports on results of a project funded by the Victorian Department of Sustainability and Environment to perform a broad-scale assessment of the total water yield impact resulting from the two bushfires. Impacts are estimated in terms of annual changes in streamflow compared to conditions immediately prior to the 2003 bushfire. The modelling approach used to estimate the impacts on streamflow was the Bushfire Impact on Streamfl ow Yield model. Annual streamflow response curves were produced at each study catchment outlet, as well as spatially explicit datasets showing change in streamflow across the study catchment. Impacts from the two fires were then aggregated to estimate the total change in streamflow yield relative to flows into the River Murray, Eildon Reservoir and the Gippsland Lakes. [ABSTRACT FROM AUTHOR]