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Chergui B, Pleguezuelos JM, Fahd S, Santos X. Modelling functional response of reptiles to fire in two Mediterranean forest types. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 732:139205. [PMID: 32438172 DOI: 10.1016/j.scitotenv.2020.139205] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 05/01/2020] [Accepted: 05/02/2020] [Indexed: 06/11/2023]
Abstract
Fire is one of the main disturbances to terrestrial environments, transforming habitat structure and affecting community composition. Coupled with fire, forest type and vegetation structure modulate the taxonomic response to fire by ectotherm organisms such as reptiles. The response of each reptile species to fire is based on their functional attributes, which make some species resilient to fire and others vulnerable to that disturbance and only adapted to long-unburnt landscapes. We studied the functional response of a reptile community at 13 burnt sites within the African rim of the Western Mediterranean, and in two contrasting forest types, i.e. native cork oak forests (five sites) and pine plantations (eight sites). We compiled seven functional traits for the reptile species in the study areas, and quantified reptile functional diversity at each sampled plot. Variation in this index was examined from burnt to nearby unburnt plots, both in cork oak and pine forests, with generalized linear mixed models. Redundancy analysis was used to identify which functional traits were associated with particular plot types. We found 2149 individual reptiles from 15 species. The functional response of reptiles to fire was forest-type dependent: functional richness did not change with fire in cork oak forest plots, but increased with fire in the pine plantation ones. High reptile functional richness in cork oak plots was due to high species richness in this forest type. The functional-redundancy analysis showed that cork oak forest hosts a reptile community functionally composed of small Mediterranean ground- and rock-dwelling lizards. In pine plantation plots, however, saxicolous geckos and phytophagous tortoises indicate the availability of other microhabitat and food resources to be exploited by reptile species with different functional traits.
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Ferreira E, Kalliola R, Ruokolainen K. Bamboo, climate change and forest use: A critical combination for southwestern Amazonian forests? AMBIO 2020; 49:1353-1363. [PMID: 31797166 PMCID: PMC7240005 DOI: 10.1007/s13280-019-01299-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 08/13/2019] [Accepted: 11/18/2019] [Indexed: 06/10/2023]
Abstract
About 160 000 km2 of forests in the border zone between Brazil and Peru are dominated by semi-scandent bamboos (Guadua spp.). We argue that both predicted decreased precipitation during the dry season and widespread anthropogenic disturbances will significantly increase the distribution and biomass of bamboos in the area. Seasonal dryness favours the growth of evergreen bamboos in relation to trees that shed their leaves during the dry season. Disturbance can be beneficial for the bamboo because, as a clonal plant, it is often able to recover more rapidly than trees. It also withstands dry season better than many trees. The bamboo life cycle ends in a mass mortality event every 28 years, producing potential fuel for a forest fire. Presently, natural forest fires hardly exist in the area. However, in the projected future climate with more pronounced dry season and with increased fuel load after bamboo die-off events the forests may start to catch fire that has escaped from inhabited areas or even started naturally. Fires can kill trees, thus further increasing the fuel load of the forest. As a result, the landscape may start to convert to a savanna ecosystem.
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Shayanfar A, Ghaderi-Far F, Behmaram R, Soltani A, Sadeghipour HR. Impacts of fire cues on germination of Brassica napus L. seeds with high and low secondary dormancy. PLANT BIOLOGY (STUTTGART, GERMANY) 2020; 22:647-654. [PMID: 32215992 DOI: 10.1111/plb.13115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Accepted: 03/16/2020] [Indexed: 06/10/2023]
Abstract
Agricultural burning is used in farm management operations; however, information about the impact of fire cues on the release and/or induction of secondary dormancy in crop seeds is scarce. Seeds from two oilseed rape cultivars were induced for high (HD) or low (LD) secondary dormancy using polyethyleneglycol (PEG) pre-treatment, and their germination after exposure to various fire cues was compared to control PEG pre-treated and non-dormant seeds. Non-dormant seed germination was unaffected by various fire cues. Low doses of aerosol smoke released secondary dormancy in HD seeds, while higher doses increased dormancy of LD seeds. Dilute smoke water also released HD seed secondary dormancy, but concentrated smke water enhanced dormancy in both LD and HD seeds. The concentrated aqueous extracts from charred oilseed rape straw only promoted germination of HD seeds, while dilution inhibited LD seed germination. Heat shock (80 °C, 5 min) released secondary dormancy in HD seeds; however, higher temperatures and/or increased exposure time was associated with seed death. GC-MS analyses of smoke water revealed two butenolides and an array of monoaromatic hydroxybenzene compounds with potential germination inhibitor or promoter activity. The extent of secondary dormancy induction in seeds affects their subsequent responses to fire cues. Both aerosol smoke and smoke water have both germination promoter and inhibitor activity. Lacking any butenolides, aqueous extracts of charred straw contain a potential germination stimulating steroid, i.e. ergosterol. The significance of fire-derived cues on behaviour of oilseed rape seeds in the soil seed bank is discussed.
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Lautenschläger T, Teutloff N, Günther M, Neinhuis C. Adansonia digitata germination tests. Elephants or heat: what causes scarification of seed to facilitate germination? BOTANICAL STUDIES 2020; 61:19. [PMID: 32548795 PMCID: PMC7297922 DOI: 10.1186/s40529-020-00296-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Accepted: 06/06/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND The dormancy of Adansonia digitata seeds is well known. For propagation purposes, plenty of germination tests were conducted, however, rarely taking the ecology of baobab into account. Our main goal, therefore, is to identify the decisive natural trigger for breaking the dormancy. We therefore performed 31 different tests and their influence on the germination rate (time to germination and proportion of seeds germinating). RESULTS The highest germination rates were reached in the heat tests while elephant's digestion seems to stimulate germination of Adansonia digitata only to a limited extent. The chalazal slit of the seed represents the primary site of water entry. Tannins concentrated in this region that are influenced by temperature play an important role for inhibiting the germination. CONCLUSION As a result, the hypothesis is formulated that germination success strongly depends on heat, provoked by wildfires or prolonged exposition to the sun causing decomposition of tannins by high temperatures rather than on digestion.
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Al-Shamsi M, Fuchs PC, Grigutsch D, Horter J, Seyhan H, Koenigs I, Siebdrath J, Schiefer JL. Are burn centers in German-speaking countries prepared to respond to a burn disaster? Survey-based study. Burns 2020; 46:1612-1619. [PMID: 32532478 DOI: 10.1016/j.burns.2020.04.032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 04/19/2020] [Accepted: 04/24/2020] [Indexed: 11/26/2022]
Abstract
Burn disasters present a challenge not only to burn centers but the entire healthcare system. Most burn centers worldwide are unprepared to deal with a burn disaster as it is an uncommon event. We investigated the status of burn center preparedness in German-speaking countries to respond to a burn disaster. Self-administered survey questionnaires were sent to the directors of burn centers; the questions of survey used before in a similar way in Belgium were translated into German language. Of the 46 questioned burn centers, 32 (78%) responded, including all of the German adult burn centers. A clear difference in the preparation status of the burn centers in the three countries was observed due to geopolitical factors such as decentralized healthcare systems. However, the healthcare system is generally well-prepared concerning command, transfer, and capacity to provide sustained supplies to handle a massive influx of patients. Nevertheless, there are some gaps in the areas of planning and preparation, funding for disaster activities, and regular training of staff for burn disasters. We call for a unified burn disaster plan and increased cooperation between burn centers and civil defense regarding communication and training. We strongly recommend the implementation of a special disaster fund and telemedicine in disaster management to circumvent shortages in burn staff.
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Torres-Rojas D, Hestrin R, Solomon D, Gillespie AW, Dynes JJ, Regier TZ, Lehmann J. Nitrogen speciation and transformations in fire-derived organic matter. GEOCHIMICA ET COSMOCHIMICA ACTA 2020; 276:170-185. [PMID: 32362680 PMCID: PMC7171705 DOI: 10.1016/j.gca.2020.02.034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 02/26/2020] [Indexed: 06/11/2023]
Abstract
Vegetation fires are known to have broad geochemical effects on carbon (C) cycles in the Earth system, yet limited information is available for nitrogen (N). In this study, we evaluated how charring organic matter (OM) to pyrogenic OM (PyOM) altered the N molecular structure and affected subsequent C and N mineralization. Nitrogen near-edge X-ray absorption fine structure (NEXAFS) of uncharred OM, PyOM, PyOM toluene extract, and PyOM after toluene extraction were used to predict PyOM-C and -N mineralization potentials. PyOM was produced from three different plants (e.g. Maize-Zea mays L.; Ryegrass-Lollium perenne L.; and Willow-Salix viminalix L.) each with varying initial N contents at three pyrolysis temperatures (350, 500 and 700 °C). Mineralization of C and N was measured from incubations of uncharred OM and PyOM in a sand matrix for 256 days at 30 °C. As pyrolysis temperature increased from 350 to 700 °C, aromatic C[bond, double bond]N in 6-membered rings (putative) increased threefold. Aromatic C[bond, double bond]N in 6-membered oxygenated ring increased sevenfold, and quaternary aromatic N doubled. Initial uncharred OM-N content was positively correlated with the proportion of heterocyclic aromatic N in PyOM (R2 = 0.44; P < 0.0001; n = 42). A 55% increase of aromatic N heterocycles at high OM-N content, when compared to low OM-N content, suggests that higher concentrations of N favor the incorporation of N atoms into aromatic structures by overcoming the energy barrier associated with the electronic and atomic configuration of the C structure. A ten-fold increase of aromatic C[bond, double bond]N in 6-membered rings (putative) in PyOM (as proportion of all PyOM-N) decreased C mineralization by 87%, whereas total N contents and C:N ratios of PyOM had no effects on C mineralization of PyOM-C for both pyrolysis temperatures (for PyOM-350 °C, R2 = 0.15; P < 0.27; for PyOM-700 °C, R2 = 0.22; P < 0.21). Oxidized aromatic N in PyOM toluene extracts correlated with higher C mineralization, whereas aromatic N in 6-membered heterocycles correlated with reduced C mineralization (R2 = 0.56; P = 0.001; n = 100). Similarly, aromatic N in 6-membered heterocycles in PyOM remaining after toluene extraction reduced PyOM-C mineralization (R2 = 0.49; P = 0.0006; n = 100). PyOM-C mineralization increased when N atoms were located at the edge of the C network in the form of oxidized N functionalities or when more N was found in PyOM toluene extracts and was more accessible to microbial oxidation. These results confirm the hypothesis that C persistence of fire-derived OM is significantly affected by its molecular N structure and the presented quantitative structure-activity relationship can be utilized for predictive modeling purposes.
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Lemoine S, Grognard G, Chabernaud JL, Jost D, Travers S, Prunet B. Pediatric victims involved in urban fires in Paris and its suburbs: Epidemiology, prehospital care, and lessons learned. Arch Pediatr 2020; 27:196-201. [PMID: 32331913 DOI: 10.1016/j.arcped.2020.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 12/18/2019] [Accepted: 03/28/2020] [Indexed: 10/24/2022]
Abstract
AIM The literature includes few reports on the prehospital care of pediatric casualties of urban house fires. Here we aimed to describe the epidemiology of pediatric fire victims, focusing on their injuries, prehospital care, and survival. METHODS This retrospective study included children under 15 years of age who were victims of urban house fires and who received care from prehospital medical teams. The variables analyzed included epidemiology, specific care provided by prehospital emergency services, the number of cardiac arrests, and survival rates. RESULTS Over the 15-month study period, 365 house fires required the presence of at least one prehospital medical team. Casualties of these fires included 121 pediatric victims (median age, 4 years [interquartile range: 2-9 years]). All children were initially treated by a prehospital medical team that was not specialized in pediatrics. Six children (4.9%) received secondary treatment from a pediatric support team. Of the 121 children, 114 (94.2%) suffered from smoke inhalation and seven (5.8%) from burns. Two patients who were in cardiac arrest at their initial medical care did not survive. CONCLUSION Pediatric fire casualties were initially managed by prehospital medical teams that were not specialized in pediatrics. As in adults, the main injuries were secondary to smoke inhalation, but this has increased toxicity in children. Prehospital teams not specialized in pediatrics can optimize their practice via the sharing of experiences, team training, and cognitive aid checklist for pediatric fire victims.
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Gunn BF, Murphy DJ, Walsh NG, Conran JG, Pires JC, Macfarlane TD, Birch JL. Evolution of Lomandroideae: Multiple origins of polyploidy and biome occupancy in Australia. Mol Phylogenet Evol 2020; 149:106836. [PMID: 32304826 DOI: 10.1016/j.ympev.2020.106836] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 04/06/2020] [Accepted: 04/09/2020] [Indexed: 02/03/2023]
Abstract
Asparagaceae: Lomandroideae are a species-rich and economically important subfamily in the monocot order Asparagales, with a center of diversity in Australia. Lomandroideae are ecologically diverse, occupying mesic and arid biomes in Australia and possessing an array of key traits, including sexual dimorphism, storage organs and polyploidy that are potentially adaptive for survival in seasonally arid and fire-dependent habitats. The Lomandroideae phylogeny was reconstructed using maximum likelihood and Bayesian inference criteria, based on plastome data from genome-skimming to infer relationships. A fossil-calibrated chronogram provided a temporal framework for understanding trait transitions. Ancestral state reconstructions and phylogenetic comparative trait correlation analyses provided insights into the evolutionary and ecological drivers associated with Lomandroideae diversification. Lomandroideae diverged from the other Asparagaceae ca. 56.61 million years ago (95% highest posterior density values 70.31-45.34 million years) and the major lineages diversified since the Oligocene. The most recent common ancestor of the clade likely occupied the mesic biome, was hermaphroditic and geophytic. Biome occupancy transitions were correlated with polyploidy and the presence of storage roots. Polyploidy potentially serves as an "enabler" trait, generating novel phenotypes, which may confer tolerance to climatic ranges and soil conditions putatively required for expansion into and occupation of new arid biomes. Storage roots, as a key factor driving biome transitions, may have been associated with fire rather than with aridification events in the Australian flora. This study contributes significantly to our understanding of biome evolution by identifying polyploidy and storage organs as key factors associated with transitions in biome occupancy in this lineage.
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Liu T, He G, Lau AKH. Statistical evidence on the impact of agricultural straw burning on urban air quality in China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 711:134633. [PMID: 32000317 DOI: 10.1016/j.scitotenv.2019.134633] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 09/19/2019] [Accepted: 09/23/2019] [Indexed: 06/10/2023]
Abstract
Agricultural straw burning is prevalent globally with a long history, but evidence on its pollution and health impact is limited in many countries. This study quantifies the effect of agricultural straw burning on urban air quality in China. Fixed-effects (FE) panel regression models are employed to link straw burning points detected by high-resolution satellites to air quality monitored at 1650 ground-level stations from 2013 to 2015. The method can explain over 80% of the monthly variation in urban air quality during straw burning seasons. The results show that straw burning primarily affects particulate matter, and has negligible effects on other pollutants. Specifically, ten additional burning points in a month in the rural farmland of a city can lead to a 5.19 ± 2.54 µg/m3 (3.67%±1.76%) increase in urban PM10 concentration. The effect is statistically significant for monthly burnings over 20 points. Upwind burnings' effect is 2-4 times larger than that of non-upwind burnings. The contribution from straw burning remains significant for daily and annual PM10 in urban areas. These estimates imply that straw burning should be properly regulated to improve air quality and protect public health in China, and the method and findings have broad implications for other agrarian regions with similar issues.
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Wellnitz T, Barlow JL, Dick CM, Shaurette TR, Johnson BM, Wesley T, Weiher E. Campsites, forest fires, and entry point distance affect earthworm abundance in the Boundary Waters Canoe Area Wilderness. PeerJ 2020; 8:e8656. [PMID: 32140309 PMCID: PMC7047863 DOI: 10.7717/peerj.8656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 01/28/2020] [Indexed: 11/20/2022] Open
Abstract
Factors controlling the spread of invasive earthworms in Minnesota’s Boundary Waters Canoe Area Wilderness are poorly known. Believed to have been introduced by anglers who use them as bait, invasive earthworms can alter the physical and chemical properties of soil and modify forest plant communities. To examine factors influencing earthworm distribution and abundance, we sampled 38 islands across five lakes to assess the effects of campsites, fire and entry point distance on earthworm density, biomass and species richness. We hypothesized that all three parameters would be greater on islands with campsites, lower on burned islands and would decrease with distance from the wilderness entry point. In addition to sampling earthworms, we collected soil cores to examine soil organic matter and recorded ground and vegetation cover. Campsite presence was the single most important factor affecting sampled earthworm communities; density, biomass and species richness were all higher on islands having campsites. Fire was associated with reduced earthworm density, but had no direct effects on earthworm biomass or species richness. Fire influenced earthworm biomass primarily through its negative relationship to groundcover and through an interaction with entry point distance. Entry point distance itself affected earthworm density and biomass. For islands with campsites, earthworm biomass increased with distance from the entry point.
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Francos M, Úbeda X, Pereira P. Impact of bon fires on soil properties in an urban park in Vilnius (Lithuania). ENVIRONMENTAL RESEARCH 2020; 181:108895. [PMID: 31740035 DOI: 10.1016/j.envres.2019.108895] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 11/03/2019] [Accepted: 11/04/2019] [Indexed: 06/10/2023]
Abstract
Lighting bonfires in urban parks is a widespread practice. However, few studies have examined their impact on soil properties. The aim of this study was to analyze the impact of bonfires on the soil properties of an urban park in Vilnius, Lithuania. The properties studied were soil water repellency (SWR), aggregate stability (AS), soil organic matter (SOM) content, total nitrogen (TN), inorganic carbon (IC), pH, electrical conductivity (EC), extractable calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), aluminum (Al), manganese (Mn), iron (Fe), zinc (Zn), copper (Cu), boron (B), chromium (Cr), available phosphorus (P), silicon (Si) and sulfur (S). Soil ratios calculated were carbon/nitrogen ratio (C/N), Ca + Mg/(Na + K)1/2 (SPAR), Ca:Al and Ca:Mg. Three areas were studied: Site 1) Pinus sylvestris L. and Quercus robur L.; Site 2) Aesculus glabra Wild.; and Site 3) Pinus sylvestris L. and Acer plantanoides L. At each site, 20 samples were collected (10 within the bonfire area, 10 from a control area). The results showed significantly higher values of SOM, IC, pH, EC, Ca, Mg, Na, K, P, Al, Zn, Cu, Cr, S, C/N ratio, Ca:Al ratio and Ca:Mg ratio in bonfire soils than in control unburned soils. In bonfire soils, significantly lower values were recorded of SWR, AS, TN, SOM, Al, Mn, Fe, Cr, S and SPAR comparing to control soils. Most affected area by the bonfire was Site 1, which presented a marked increase in heavy metal content comparing to the control. The impact of soil heating was evident in AS, IC, pH, extractable Ca, Mg, Na, K, P, Al, Zn, Cu, Cr, S, and in its ratios. Protective measures are needed to limit bonfires and prohibit the burning of hazardous materials.
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Tamrat M, Atickem A, Tsegaye D, Evangelista P, Bekele A, Stenseth NC. The effect of season and post- fire on habitat preferences of the endangered Swayne's hartebeest (Alcelaphus buselaphus swaynei) in Maze National Park, Ethiopia. BMC Ecol 2020; 20:5. [PMID: 31992270 PMCID: PMC6986001 DOI: 10.1186/s12898-020-0275-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 01/16/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The availability of preferred habitats determines the spatial and temporal distribution of herbivores in savanna ecosystems. Understanding habitat preference of a targeted wildlife species is crucial for developing effective conservation strategies. Habitat preference of large grazers in connection to grass height and post-fire effect has been debated for the last century. Here, we examined the effects of season, grass height and burning on the habitat preference on Swayne's hartebeest (Alcelaphus buselaphus swaynei) in Maze National Park. Data for seasonal habitat selection were collected using both direct observation along established transect lines and pellet counting using permanently established plots. Every month, we measured grass height commonly preferred by Swayne's hartebeest in grassland habitat. Starting from the first week of burning, we recorded the abundance of Swayne's hartebeest in both burned and unburned grassland patches. RESULTS From detected pellets, 94.3% were recorded in the grassland habitat indicating that other habitat types are less used despite their extensive cover > 50% of the Park. During wet and early dry seasons, Swayne's hartebeest exclusively preferred grassland habitat. We found that 85.2% (n = 1079) and 85.3% (n = 593) of individuals observed in areas with a grass height below 30 cm during wet and early-dry seasons, respectively; while 70.9% (n = 2288) preferred grass height below 30 cm during the dry season. The density of Swayne's hartebeest in burned grassland area was higher than unburned grassland areas up to 150 days since burning. However, in unburned grassland areas, the density was initially low but showed increasing trend for consecutive days, reaching similar density with burned areas after 150 days since burning. CONCLUSION Swayne's hartebeest exclusively preferred grassland habitat, particularly during wet and early-dry seasons, shortest available grass height in all seasons and were attracted to burned grassland areas. Our results suggested that fire played an important role in maintaining habitat quality in grassland, and that management should continue using controlled burning as a tool for the conservation of Swayne's hartebeest. However, we remain cautious of our findings given the paucity of information regarding other confounding factors and the absence of long-term data on fire disturbance.
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Sinclair AL, Graham LLB, Putra EI, Saharjo BH, Applegate G, Grover SP, Cochrane MA. Effects of distance from canal and degradation history on peat bulk density in a degraded tropical peatland. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 699:134199. [PMID: 31522054 DOI: 10.1016/j.scitotenv.2019.134199] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Revised: 08/28/2019] [Accepted: 08/29/2019] [Indexed: 06/10/2023]
Abstract
Over recent decades, the combination of deforestation, peat drainage and fires have resulted in widespread degradation of Southeast Asia's tropical peatlands. These disturbances are generally thought to increase peat soil bulk density through peat drying and shrinkage, compaction, and consolidation. Biological oxidation and fires burning across these landscapes also consume surface peat, exposing older peat strata. The prevalence and severity of deforestation, peat drainage and fire are typically greater closer to canals, built to drain peatlands and provide access routes for people. We compared bulk densities of 240cm peat profiles from intact forests and degraded peatlands broadly, and also assessed differences between degraded peatlands near-to-canals (50-200m from the nearest canal) and far-from-canals (300+ m from the nearest canal). The effects of vegetation type and fire frequency on bulk density, irrespective of the distance from canal, were also investigated. Mean bulk density values ranged between 0.08 and 0.16gcm-3 throughout the 240cm peat profiles. Drainage of peat near-to-canals increased bulk density of peat above the minimum water table depth. Degradation by deforestation and fire also increased bulk densities of upper peat strata, albeit with greater variability. Peat sampled further from canals experienced less intense water table drawdowns, buffering them from drainage effects. These areas were also more commonly forested and burnt less frequently. Differences in bulk densities below minimum water table levels are less clear, but may reflect lowering of the current peat surface in degraded peatlands broadly. These results clearly show that important differences in bulk density exist across degraded peatlands that are spatially dependent on distance from canals and disturbance history. These landscape features should be taken into account when designing future bulk density sampling efforts and peatland restoration programs, or when extrapolating from existing sources in order to make accurate inferences from them.
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Choe L, Ramesh S, Grosshandler W, Hoehler M, Seif M, Gross J, Bundy M. Behavior and Limit States of Long-Span Composite Floor Beams with Simple Shear Connections subject to Compartment Fires: Experimental Evaluation. JOURNAL OF STRUCTURAL ENGINEERING (NEW YORK, N.Y.) 2020; 146:https://doi.org/10.1061/(asce)st.1943-541x.0002627. [PMID: 33041477 PMCID: PMC7542547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
This paper presents the results of compartment fire experiments on four 12.8 m long composite floor beams with various end support conditions. Specimens were constructed as partially-composite beams, consisting of W18×35 steel beams and 83 mm thick lightweight concrete slabs cast on top of 76 mm deep ribbed steel deck units. Test variables included two types of simple shear connections (shear-tab and welded-bolted double-angle connections) and the presence or absence of slab continuity over the girders. Each specimen was subjected to gravity loading using hydraulic actuators and 4000 kW compartment fires produced using natural gas-fueled burners. This study evaluated the characteristics of the fire loading and thermal and structural responses of the specimens. The test results indicated that there were significant effects of thermal restraints on the behavior and failure modes of the specimens with simple shear connections. The specimens resisted gravity loads at large vertical displacements near midspan (approximately a ratio of span length over 20) without collapse under fire loading. However, various limit states and vulnerabilities to fires were observed, including local buckling of steel beams near supports, flexural failure (yielding of steel beams and concrete fracture near restrained end supports), and connection failure (weld shear or bolt shear) during heating and cooling which could lead to partial or total collapse of the floor system.
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Hoehler MS, Andres B, Bundy MF. Lateral Resistance Reduction to Cold-Formed Steel-Framed Shear Walls under Various Fire Scenarios. JOURNAL OF STRUCTURAL ENGINEERING (NEW YORK, N.Y.) 2020; 146:https://doi.org/10.1061/(asce)st.1943-541x.0002610. [PMID: 33041476 PMCID: PMC7542675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
This paper examines the structural response of cold-formed steel-framed building lateral force-resisting systems under combinations of simulated earthquake and fire loading. Full-scale experiments with gypsum-sheet steel composite panel sheathed walls, oriented strand board sheathed walls, and steel strap braced walls are presented. Twenty-two test specimens are subjected sequentially to combinations of cyclic shear deformation and fires of varying intensity; some approximate temperatures in standard furnace tests, and most have characteristics of actual building fires. In select tests, the walls are predamaged to simulate fire following an earthquake. The results show a progressive decrease of postfire lateral load capacity with increasing fire intensity for all walls; however, each wall type exhibits varied sensitivity to the fire intensity as well as to predamage. By understanding the response of these structural systems in real fires, designers can better plan for situations in which multiple hazards, including fire, exist.
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Bautista-Reyes AL, Cruz-Vega F, Sánchez-Echeverría JC, Loría-Castellanos J, Balderas-Fajardo J, Elizondo-Argueta S. [Evacuation of critical care areas due to an initial outbreak of fire in a second level hospital]. REVISTA MEDICA DEL INSTITUTO MEXICANO DEL SEGURO SOCIAL 2019; 57:338-339. [PMID: 33001608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
In this letter to the editor, it is exposed an initial outbreak of fire that affected a secondary care center in Córdova, Veracruz, Mexico, and, most of all, the lack of a hospital fire evacuation plan in the presence of a fire event.
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Boschetti L, Roy DP, Giglio L, Huang H, Zubkova M, Humber ML. Global validation of the collection 6 MODIS burned area product. REMOTE SENSING OF ENVIRONMENT 2019; 235:10.1016/j.rse.2019.111490. [PMID: 32440029 PMCID: PMC7241595 DOI: 10.1016/j.rse.2019.111490] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
This paper presents a Stage 3 validation of the recently released Collection 6 NASA MCD64A1 500 m global burned area product. The product is validated by comparison with Landsat 8 Operational Land Imager (OLI) image pairs acquired 16 days apart that were visually interpreted. These independent reference data were selected using a stratified random sampling approach that allows for probability sampling of Landsat data in both time and in space. A total of 558 Landsat 8 OLI image pairs (1116 images), acquired between March 1st, 2014 and March 19th , 2015, were selected and used to validate the MCD64A1 product. The areal accuracy of the MCD64A1 product was characterized at the 30 m resolution of the Landsat independent reference data using standard accuracy metrics derived from global and from biome specific confusion matrices. Because a probability based Stage 3 sampling protocol was followed, unbiased estimators of the accuracy metrics and associated standard errors could be used. Globally, the MCD64A1 product had an estimated 40.2% commission error and 72.6% omission error; the prevalence of omission errors is reflected by a negative estimated bias of the mapped global area burned relative to the Landsat independent reference data (-54.1%). Globally, the standard errors of the accuracy metrics were less than 6%. The lowest errors were observed in the boreal forest biome (27.0% omission and 23.9% estimated commission errors) where burned areas tend to be large and distinct, and remain on the landscape for long periods, and the highest errors were in the Tropical Forest, Temperate Forest, and Mediterranean biomes (estimated > 90% omission error and > 50% commission error). The product accuracy was also characterized at coarser scale using metrics derived from the regression between the proportion of coarse resolution grid cells detected as burned by MCD64A1 and the proportion mapped in the Landsat 8 interpreted maps. The errors of omission and commission observed at 30 m resolution compensate to a considerable extent at coarser resolution, as indicated by the coefficient of determination (r2 > 0.70), slope (> 0.79) and intercept (-0.0030) of the regression between the MCD64A1 product and the Landsat independent reference data in 3 km, 4 km, 5 km, and 6 km coarse resolution cells. The Boreal Forest, Desert and Xeric Shrublands, Temperate Savannah and Tropical Savannah biomes had higher r 2 and slopes closer to unity than the Temperate Forest, Mediterranean, and Tropical Forest biomes. The analysis of the deviations between the proportion of area burned mapped by the MCD64A1 product and by the independent reference data, performed using 3 km × 3 km and 6 km × 6 km coarse resolution cells, indicates that the large negative bias in global area burned is primarily due to the systematic underestimation of smaller burned areas in the MCD64A1 product.
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Kahn SA, Leonard C, Lee YG, Boatwright R, Flamm T, Woods J. A pilot survey of Southeastern firefighters: Safety practices, use of protective gear, and injury. Burns 2019; 46:298-302. [PMID: 31780278 DOI: 10.1016/j.burns.2019.03.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 03/03/2019] [Accepted: 03/11/2019] [Indexed: 11/16/2022]
Abstract
INTRO There were over 60 firefighter line of duty deaths and roughly 30,000 injuries in the United States in 2016. Modern thermoprotective gear has reduced the risks firefighters face from both thermal and inhalation injury, but must be used properly to be effective. The purpose of this study is to examine gear use and associated injury in firefighters. METHODS Surveys were distributed with questions about demographics, gear usage, and maintenance practices. If previously injured, firefighters described the injury, treatment, and recovery. RESULTS Of the 50 surveys distributed, 37 were returned (72%). A majority of respondents (70%) reported wearing incomplete gear. Those who reported injury were more likely to have omitted gear (81% vs 45%). For all respondents, the items most commonly omitted were hood (58%), gloves (22%), and earflaps (22%). Regular cleaning of gear was not practiced by 39% of burned respondents and 46% had not had their gear sized within 2 years. Serious burns were reported by 41% of respondents. Mean burn size was 7% total body surface area (TBSA), and 11% reported self-treating their burns, including 63.5% who continued to work despite suffering a 2nd or 3rd degree burn injury. Only 17% were treated at a burn center, and this group missed anywhere from two shifts to 8 months of work. CONCLUSIONS Firefighters risk injury by omitting gear and not adhering to National Fire Protection Association (NFPA) guidelines on gear sizing, maintenance, and station wear. Firefighters also frequently self-treat serious burns despite unique considerations regarding re-injury. National trends related to gear use and injury risk should be studied further, and standards should be developed for ensuring safe return to work.
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Nicholls S. Impacts of environmental disturbances on housing prices: A review of the hedonic pricing literature. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 246:1-10. [PMID: 31170618 DOI: 10.1016/j.jenvman.2019.05.144] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 04/24/2019] [Accepted: 05/28/2019] [Indexed: 06/09/2023]
Abstract
The global environment is susceptible to many types of change, including alterations to the world's climate. Climate change has been linked to a host of modifications to the natural environment, including the increasing frequency and severity of disturbances such as pest outbreaks, invasions by non-native species, and wildfire. These in turn pose substantial risks to human wellbeing and health. Estimates of the direct and indirect costs of these events are important prerequisites to well-rounded cost-benefit analyses of preventative or control measures, themselves essential components of appropriate education, policy and management responses. This review brings together the evidence with respect to the impacts of disturbances such as pests, invasive species and wildfire on residential property values as measured using the hedonic pricing method. It demonstrates that whilst most disturbances have the expected negative or an insignificant house price impact, in some cases disturbances can lead to housing price rise. The possible causes and implications of these unanticipated positive price responses are discussed. Broader consequences of all directions of price impact are also considered, in particular for the development and implementation of polices designed to prevent the occurrence or spread of disturbances, or at a minimum mitigate their negative effects.
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Yekwayo I, Pryke JS, Gaigher R, Samways MJ. Wandering spiders recover more slowly than web-building spiders after fire. Oecologia 2019; 191:231-240. [PMID: 31350591 DOI: 10.1007/s00442-019-04471-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 07/18/2019] [Indexed: 11/28/2022]
Abstract
Fire is a natural feature of many ecosystems, with some vegetation types highly adapted to fire. However, very little is known about the effect of fire on spiders, especially as fires have become more frequent owing to human activity. We determine whether different spider functional guilds (web builders vs. wanderers) respond differently to fires in the sclerophyllous fynbos. We determine also the effect of rockiness as refuge for these guilds and whether it influences their post-fire recovery. There were three site categories of time-since-last fire: 3 months, 1 year, and 7 years. We found that fire caused a decline in spider richness and abundance, with the 3-month category supporting the lowest. In sites that were burned within 1 year, abundance of wanderers was as high as in sites that had 7 years to recover, whereas species richness and abundance of web builders in sites that were burned 1 year ago were as low as in recently burned sites. However, assemblages of wanderers differed among categories, while no differences were observed for web builders, highlighting that wanderers took longer time to recover than web builders. Species richness and abundance of both guilds were not affected by different levels of rockiness. However, rockiness is important in shaping assemblages of wanderers. The results emphasize that the assemblages of greatest conservation concern with increased fire frequencies are wanderers and are candidate surrogates for monitoring post-fire recovery. These results highlight the need to allow fynbos vegetation to recover fully between fire intervals and draws attention to the dangers of frequent unplanned fires.
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Jean Baptiste A, Macario PA, Islebe GA, Vargas-Larreta B, Pool L, Valdez-Hernández M, López-Martínez JO. Secondary Succession under invasive species ( Pteridium aquilinum) conditions in a seasonal dry tropical forest in southeastern Mexico. PeerJ 2019; 7:e6974. [PMID: 31179179 PMCID: PMC6544012 DOI: 10.7717/peerj.6974] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Accepted: 04/15/2019] [Indexed: 11/20/2022] Open
Abstract
The role of invasive species in ecosystem functioning represents one of the main challenges in ecology. Pteridium aquilinum is a successful cosmopolitan invasive species with negative effects on the ecological mechanisms that allow secondary succession. In this study, we evaluated the influence of P. aquilinumon secondary succession under different disturbances in a seasonal dry forest of the Yucatán Peninsula. We determined species richness, composition and the relative importance value in four sampling units. Fabaceae followed by Asteraceae, Meliaceae, Rubiaceae, Sapindaceae and Verbenaceae were the most species rich families. A dissimilarity analysis determined significant differences in beta diversity between sampling units. With a generalized linear model we found that species richness was best explained by site conditions, followed by calcium and soil organic matter. Also, the generalized linear model showed that abundance resulted in a strong correlation with site conditions and soil characteristics. Specific soil conditions related to phosphoro and calcium were also detected as beneficiary to the successional processes. Our results suggest that applying fire restriction and periodic cutting of the bracken fern, this can increase a higher diversity of species.
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Bentley S, Iavicoli L, Boehm L, Agriantonis G, Dilos B, LaMonica J, Smith C, Wong L, Lopez T, Galer A, Kessle S. A Simulated Mass Casualty Incident Triage Exercise: SimWars. MEDEDPORTAL : THE JOURNAL OF TEACHING AND LEARNING RESOURCES 2019; 15:10823. [PMID: 31139741 PMCID: PMC6521923 DOI: 10.15766/mep_2374-8265.10823] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 03/26/2019] [Indexed: 05/31/2023]
Abstract
INTRODUCTION This multipatient simulation exercise encompasses triage by hospital medical providers during a mass casualty incident (MCI) involving gas line explosion with building collapse. The SimWars format allows two teams to participate in identical simulations coupled with active audience observation, followed by facilitated group discussion. The exercise requires real-time knowledge application of MCI management and helps learners develop a framework for rapidly classifying and dispositioning MCI patients. METHODS Two teams of provider pairs completed MCI triage of 12 simulated patients in 8 minutes with an objective of quickly and accurately dispositioning within hospital bed availability. Participants included emergency medicine and surgery physicians, with active observation by mixed provider audiences. Observers completed a checklist per patient (category: urgent/emergent/not emergent, disposition: bed type/location). At simulation conclusion, a 45-minute facilitated discussion compared observers' self-assessment of MCI patient management with the simulation teams' decisions. Finally, an expert panel discussed management decisions and MCI triage pearls. RESULTS Team performances (N = 4) and audience responses (N = 164) were similar on seven of 12 patients, allowing robust discussion. Participants completed an evaluation at exercise conclusion; 37% reported good/excellent ability to accomplish MCI initial triage and disposition before this exercise compared to 100% after, a statistically significant 63% increase. All postsurvey respondents agreed or strongly agreed that the exercise would change their MCI clinical practice. DISCUSSION The two-team format allows comparison of how different teams handle MCI triage, and active observation allows comparison of audience and team decision making.
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Klein A, Krebs O, Gehl A, Morgner J, Reeger L, Augustin C, Edler C. The use of liquid latex for detecting traces of blood following thermal exposure. Int J Legal Med 2019; 133:1567-1574. [PMID: 31020398 DOI: 10.1007/s00414-019-02068-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Accepted: 04/12/2019] [Indexed: 11/25/2022]
Abstract
In cases of crimes involving blood, the perpetrators often attempt to remove the traces they have left behind. Setting fire to the crime scene, aside from cleaning measures, seems to achieve this goal and presents a major challenge for crime scene investigators. There is only very little published information available on the effect of fire and extreme heat on blood and the detection thereof. After exposure to high temperatures of or exceeding 1.000 °C, blood is deemed to be undetectable. This study exposed 11 different potentially crime-relevant objects using a standardized and controlled procedure to temperatures of 300 °C, 700 °C, and 1.000 °C documenting the influence of heat on bloodstains and the detection of blood. The results of the forensic collection of blood traces with and without liquid latex confirmed the advantage of using the latex method. Almost all objects showed a clear luminescence-caused visualization of traces of blood after removing the soot with a latex lift. There were also fewer false positive results than in tests not using latex.
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Bian F, Coleborn K, Flemons I, Baker A, Treble PC, Hughes CE, Baker A, Andersen MS, Tozer MG, Duan W, Fogwill CJ, Fairchild IJ. Hydrological and geochemical responses of fire in a shallow cave system. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 662:180-191. [PMID: 30690353 DOI: 10.1016/j.scitotenv.2019.01.102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 01/03/2019] [Accepted: 01/10/2019] [Indexed: 06/09/2023]
Abstract
The influence of wildfire on surface soil and hydrology has been widely investigated, while its impact on the karst vadose zone is still poorly understood. A moderate to severe experimental fire was conducted on a plot (10 m × 10 m) above the shallow Wildman's Cave at Wombeyan Caves, New South Wales, Australia in May 2016. Continuous sampling of water stable isotopes, inorganic geochemistry and drip rates were conducted from Dec 2014 to May 2017. After the fire, drip discharge patterns were significantly altered, which is interpreted as the result of increased preferential flows and decreased diffuse flows in the soil. Post-fire drip water δ18O decreased by 6.3‰ in the first month relative to the average pre-fire isotopic composition. Post-fire monitoring showed an increase in drip water δ18O in the following six months. Bedrock related solutes (calcium, magnesium, strontium) decreased rapidly after the fire due to reduced limestone dissolution time and potentially reduced soil CO2. Soil- and ash-derived solutes (boron, lead, potassium, sodium, silicon, iodine and iron) all decreased after the fire due to volatilisation at high temperatures, except for SO42-. This is the first study to understand the hydrological impact from severe fires conducted on a karst system. It provides new insights on the cave recharge process, with a potential explanation for the decreased d18O in speleothem-based fire study, and also utilise the decreased bedrock solutes to assess the wildfire impacts both in short and long time scales.
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McKenna ST, Jones N, Peck G, Dickens K, Pawelec W, Oradei S, Harris S, Stec AA, Hull TR. Fire behaviour of modern façade materials - Understanding the Grenfell Tower fire. JOURNAL OF HAZARDOUS MATERIALS 2019; 368:115-123. [PMID: 30669035 DOI: 10.1016/j.jhazmat.2018.12.077] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 12/14/2018] [Accepted: 12/20/2018] [Indexed: 06/09/2023]
Abstract
The 2017 Grenfell Tower fire spread rapidly around the combustible façade system on the outside of the building, killing 72 people. We used a range of micro- and bench-scale methods to understand the fire behaviour of different types of façade product, including those used on the Tower, in order to explain the speed, ferocity and lethality of the fire. Compared to the least flammable panels, polyethylene-aluminium composites showed 55x greater peak heat release rates (pHRR) and 70x greater total heat release (THR), while widely-used high-pressure laminate panels showed 25x greater pHRR and 115x greater THR. Compared to the least combustible insulation products, polyisocyanurate foam showed 16x greater pHRR and 35x greater THR, while phenolic foam showed 9x greater pHRR and 48x greater THR. A few burning drips of polyethylene from the panelling are enough to ignite the foam insulation, providing a novel explanation for rapid flame-spread within the facade. Smoke from polyisocyanurates was 15x, and phenolics 5x more toxic than from mineral wool insulation. 1 kg of burning polyisocyanurate insulation is sufficient to fill a 50m3 room with an incapacitating and ultimately lethal effluent. Simple, additive models are proposed, which provide the same rank order as BS8414 large-scale regulatory tests.
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