36,057 results on '"fire"'
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2. Fire Detection System Using Deep CNN
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Vikkurty, Sireesha, Nagaratna Hegde, P., Chinthakrinda, Vennela Preethi, Hegde, G. P., Shetty, Sudheer, Li, Gang, Series Editor, Filipe, Joaquim, Series Editor, Ghosh, Ashish, Series Editor, Xu, Zhiwei, Series Editor, T., Shreekumar, editor, L., Dinesha, editor, and Rajesh, Sreeja, editor
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- 2025
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3. Remote Sensing in Climate Change Research
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Filchev, Lachezar, Chanev, Milen, Kacprzyk, Janusz, Series Editor, Gomide, Fernando, Advisory Editor, Kaynak, Okyay, Advisory Editor, Liu, Derong, Advisory Editor, Pedrycz, Witold, Advisory Editor, Polycarpou, Marios M., Advisory Editor, Rudas, Imre J., Advisory Editor, Wang, Jun, Advisory Editor, Dobrinkova, Nina, editor, and Fidanova, Stefka, editor
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- 2025
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4. TRC Application Potential to Strengthen and Repair Concrete Structures Exposed to Fire
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Toska, Klajdi, Beaucour, Anne-Lise, Faleschini, Flora, Pellegrino, Carlo, Noumowe, Albert, Ferrara, Liberato, editor, Muciaccia, Giovanni, editor, and di Summa, Davide, editor
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- 2025
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5. A Performance Evaluation of Cross-lingual and Monolingual IR
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Chandra, Ganesh, Asthana, Amit, Pandey, Mahima Shanker, Dixit, Manish, Dwivedi, Sanjay K., Dwivedi, Anand Prakash, Das, Swagatam, Series Editor, Bansal, Jagdish Chand, Series Editor, Jaiswal, Ajay, editor, Anand, Sameer, editor, Hassanien, Aboul Ella, editor, and Azar, Ahmad Taher, editor
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- 2025
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6. Impact of the variability of material constitutive models on the thermal response of reinforced concrete walls
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Karaki, Ghada, Hawileh, Rami A., and Naser, M.Z.
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- 2024
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7. Combined effects of corrosion and fire on load-carrying response of hot-rolled steel reinforcement
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Tariq, Faraz
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- 2024
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8. Surface-active antibiotic production as a multifunctional adaptation for postfire microorganisms.
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Liu, Mira, Du, Yongle, Koupaei, Sara, Kim, Nicole, Fischer, Monika, Zhang, Wenjun, and Traxler, Matthew
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antibiotics ,fire ,interspecies interactions ,motility ,surfactants ,Surface-Active Agents ,Soil Microbiology ,Glycolipids ,Anti-Bacterial Agents ,Fires ,Burkholderiales ,Adaptation ,Physiological ,Polycyclic Aromatic Hydrocarbons - Abstract
Wildfires affect soils in multiple ways, leading to numerous challenges for colonizing microorganisms. Although it is thought that fire-adapted microorganisms lie at the forefront of postfire ecosystem recovery, the specific strategies that these organisms use to thrive in burned soils remain largely unknown. Through bioactivity screening of bacterial isolates from burned soils, we discovered that several Paraburkholderia spp. isolates produced a set of unusual rhamnolipid surfactants with a natural methyl ester modification. These rhamnolipid methyl esters (RLMEs) exhibited enhanced antimicrobial activity against other postfire microbial isolates, including pyrophilous Pyronema fungi and Amycolatopsis bacteria, compared to the typical rhamnolipids made by organisms such as Pseudomonas spp. RLMEs also showed enhanced surfactant properties and facilitated bacterial motility on agar surfaces. In vitro assays further demonstrated that RLMEs improved aqueous solubilization of polycyclic aromatic hydrocarbons, which are potential carbon sources found in char. Identification of the rhamnolipid biosynthesis genes in the postfire isolate, Paraburkholderia kirstenboschensis str. F3, led to the discovery of rhlM, whose gene product is responsible for the unique methylation of rhamnolipid substrates. RhlM is the first characterized bacterial representative of a large class of integral membrane methyltransferases that are widespread in bacteria. These results indicate multiple roles for RLMEs in the postfire lifestyle of Paraburkholderia isolates, including enhanced dispersal, solubilization of potential nutrients, and inhibition of competitors. Our findings shed new light on the chemical adaptations that bacteria employ to navigate, grow, and outcompete other soil community members in postfire environments.
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- 2024
9. Reconciling 22,000 years of landscape openness in a renowned wilderness.
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Fletcher, Michael‐Shawn, Romano, Anthony, Lisé‐Pronovost, Agathe, Mariani, Michela, Henriquez, William, Gadd, Patricia, Heijnis, Hendrik, Hodgson, Dominic, Blaauw, Maarten, and Sculthorpe, Andry
- Abstract
Here, we explore the profound impact of the Tasmanian Aboriginal (Palawa) people on Tasmanian landscapes by examining a 22,000‐year record of landscape change from Lake Selina in western Tasmania, Australia. We analysed a sediment core for palaeoecological proxies, namely, pollen (vegetation), charcoal (fire), and geochemical data (landscape weathering). This study reveals that the contemporary landscape is a product of Palawa people's intentional and strategic fire management practices characterised by fire‐dependent buttongrass moorland and the absence of climax rainforest. Specifically, our data show that rainforest failed to re‐establish a dominance at Lake Selina following the end of the Last Glacial Maximum, as temperature and moisture increased as a result of Palawa cultural fire for at least 18,000 years. This finding challenges the long‐held notion that Tasmania's wilderness is a product of the absence of human activity. Rather, archaeological sites across western and central Tasmania demonstrate long term presence, with some of the highest artefact and faunal bone densities in the world. The study contributes to the recognition of Tasmania's west as a cultural landscape shaped by generations of Aboriginal care for Country and fire practices. [ABSTRACT FROM AUTHOR]
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- 2024
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10. Prevalence and Knowledge of Tick-Borne Disease Among Forest Management Workers in Santa Cruz, California.
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Rubino, Francesca and Foley, Janet
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Background: In Lyme-endemic areas, limited research has investigated the risk of tick-borne diseases among frontline workers in fire management. This study aimed to compare the exposure histories to ticks and tick-borne pathogens, knowledge, and prevention practices between individuals engaged in fire-related forest management and those participating in recreational activities within Santa Cruz County, CA, in an area of high risk of tick exposure. Methods: Blood samples from 55 forest workers and 58 members of the public were tested for bacterial DNA of and antibodies to Borrelia burgdorferi, Anaplasma phagocytophilum, and Rickettsia species. In addition, a questionnaire was administered to 54 workers and 84 members of the public to identify gaps in knowledge and prevention practices. Results: Although workers had a higher percentage of positive B. burgdorferi antibodies than the public (5.5% compared with 1.7%), the difference was not statistically significant. Conversely, rickettsial antibodies were more prevalent among the public (17.2% versus 3.6% for workers), but specificity to pathogenic bacteria could not be confirmed. No DNA for the three pathogens or antibodies against A. phagocytophilum were detected. Many workers and members of the public reported tick bites (67.4% of participants), with a notable 11% increase among workers in the odds of being bitten for each additional year spent working in forests. Although workers took greater precautions, significant knowledge and practice gaps were identified among both populations, such as an inability to distinguish tick species from common arthropods (mites, spiders, fleas), overestimating the size of ticks, and inappropriate tick-removal techniques. Conclusion: This study underscores the risk of tick-borne diseases faced by fire management workers in Lyme disease–endemic regions. The findings emphasize the necessity for future studies of Lyme disease within this population, and highlight the urgent need for enhanced training programs to minimize these risks. [ABSTRACT FROM AUTHOR]
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- 2024
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11. Increase in the frequency of melanism in Abert's Squirrel in Boulder, Colorado.
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Barrett, Lake H., Nunes, Christian A., and Lehtinen, Richard M.
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SQUIRRELS , *MELANISM , *CITIZEN science , *BODY temperature regulation , *CAMERAS - Abstract
In the northern portions of its range, Abert's Squirrel (Sciurus aberti) has two color morphs: a wild-type gray morph and a melanistic morph. Using camera traps, citizen science data and in-person observations in and near Boulder, Colorado (USA), we compared current color morph frequencies to those reported in a 1969–1971 study. At all study sites, we observed a large and statistically significant increase in the frequency of the melanistic morph compared to historic data. We hypothesize that this increase may be due to selection favoring the melanistic morph in a changing forest environment. [ABSTRACT FROM AUTHOR]
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- 2024
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12. The Impact of the Configuration of a Hydrogen Refueling Station on Risk Level.
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Rusin, Andrzej, Stolecka-Antczak, Katarzyna, Kosman, Wojciech, and Rusin, Krzysztof
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STORAGE tanks , *WIND speed , *TERMINALS (Transportation) , *HEAT flux , *FUELING - Abstract
The paper discusses potential hazards at hydrogen refueling stations for transportation vehicles: cars and trucks. The main hazard analyzed here is an uncontrolled gas release due to a failure in one of the structures in the station: storage tanks of different pressure levels or a dispenser. This may lead to a hydrogen cloud occurring near the source of the release or at a given distance. The range of the cloud was analyzed in connection to the amount of the released gas and the wind velocity. The results of the calculations were compared for chosen structures in the station. Then potential fires and explosions were investigated. The hazard zones were calculated with respect to heat fluxes generated in the fires and the overpressure generated in explosions. The maximum ranges of these zones vary from about 14 to 30 m and from about 9 to 14 m for a fires and an explosions of hydrogen, respectively. Finally, human death probabilities are presented as functions of the distance from the sources of the uncontrolled hydrogen releases. These are shown for different amounts and pressures of the released gas. In addition, the risk of human death is determined along with the area, where it reaches the highest value in the whole station. The risk of human death in this area is 1.63 × 10−5 [1/year]. The area is approximately 8 square meters. [ABSTRACT FROM AUTHOR]
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- 2024
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13. Past, Present, and Future of Forbs in Old-Growth Tropical and Subtropical Grasslands.
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Siebert, Frances, te Beest, Mariska, Fynn, Richard, Klimešová, Jitka, Morris, Craig, Nkuna, Sindiso, Siebert, Stefan, and Fidelis, Alessandra
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Forbs are important contributors to species diversity and ecosystem functions in low-latitude grasslands, where they support diverse herbivore communities and millions of people. Native forb assemblages tolerate disturbances and physiological stressors (fire, herbivory, drought, and frost) that together have shaped their exceptional functional diversity. Yet, compared to trees and grasses, forbs have received much less attention in grassland studies until recently. Here, we review forb-centric literature to illustrate that land conversion and responsible management of fire and herbivory are crucial to maintaining forb diversity. Management practices promoting forb diversity offer (a) high-quality food items and medicinal resources that support rural livelihoods and animal diversity (from wild ungulates and livestock to fossorial rodents and insects), including their adaptive foraging patterns, and (b) carbon and nutrient inputs that regulate belowground processes. Improved understanding of the above- and belowground regeneration strategies of forbs is critical for restoration and conservation to secure their services in future old-growth tropical and subtropical grasslands. [ABSTRACT FROM AUTHOR]
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- 2024
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14. Using demographic modeling to develop post‐fire restoration strategies for a native shrub in a sage scrub community.
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Thomson, Diane M.
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RAINFALL , *SAGE , *DROUGHTS , *CLIMATE change , *RESOURCE management , *SHRUBLANDS - Abstract
Mediterranean‐climate shrublands are key biodiversity hotspots and carbon storage pools, but are increasingly threatened by climate change, non‐native species, and altered fire regimes. Fires are important to historic shrubland disturbance cycles but can also promote non‐native plants, which may limit post‐fire native shrub recovery. Increasing drought with climate change could also reduce post‐fire shrub regeneration. I developed a stochastic, individual‐based demographic model (IBM) for the native shrub Artemisia californica, parameterized from an experimental removal of non‐native annuals after a 2013 fire in southern California. The IBM simulated A. californica recovery for 7 years after fire under different rainfall conditions (drought or pre‐drought) and non‐native removal strategies (from no years to all 7 years). Drought lowered A. californica canopy volume 7 years after fire by 90% or more. Rainfall in the second year after fire, when most A. californica germination occurred, had particularly strong effects on final canopy cover. Non‐native removal in all 7 years increased canopy volume by three times under drought conditions and 3.5 times under pre‐drought conditions. Targeting non‐native removal in the first 2 years proved nearly as effective, achieving from 88% (drought) to 95% (pre‐drought) the benefits of removal in all 7 years. In sum, low rainfall may be the most important limitation on post‐fire shrub recovery, but removal of non‐natives in years of pulsed shrub recruitment can be an effective restoration strategy even under drought conditions. More generally, this study illustrates how demographic models can help optimize the targeting of scarce management and restoration resources. [ABSTRACT FROM AUTHOR]
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- 2024
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15. Endemic darling or global change menace? A review of the woody encroacher Leucosidea sericea on the eastern Great Escarpment of southern Africa.
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Gwate, Onalenna, Dlomu†, Muxe G., Toucher, Michele, le Roux, Peter C., Martin, Grant D., and Clark, Vincent R.
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GLOBAL environmental change , *GRASSLAND fires , *NATIVE species , *GLOBAL warming , *OVERGRAZING - Abstract
• Leucosidea sericea is expanding its range and densifying. • This leads to adverse impacts of ecosystem services such as biodiversity and water provisioning. • Runoff-and-run-on dynamics partly modulate the spread of Leucosidea sericea. • Future studies should aim to understand how the distribution of Leucosidea sericea responds to global environmental changes. Rapid woody encroachment by native species is transforming grasslands and savannas across the world. The drivers of this encroachment are diverse, complex, and potentially interlinked, including fire exclusion, overgrazing, plant-plant interactions, extirpation of local mega-fauna, carbon fertilisation, and global warming. In southern Africa, woody encroachment is a well-studied phenomenon that has primarily been documented in savanna and woodland systems, but there has been little work on woody encroachment in southern African mountain systems. These host much of the region's exceptional endemism and provide most of the region's water, and bush encroachment may have serious impacts on both. Leucosidea sericea Eckl. & Zeyh., is a Rosaceous shrub-tree endemic to the eastern Great Escarpment (Sneeuberg, South Africa, to Nyanga, Zimbabwe) that is believed to be rapidly expanding and densifying, however, there is very limited research on this species. Accordingly, we provide the first comprehensive review of the autecology of the species, outlining a summary of past research, and highlighting research needs related to encroachment, impact, and management. In addition, we demonstrate the potential for using repeat photography to study L. sericea ecology, confirming encroachment at some sites and highlighting how run-off-run-on dynamics may influence L. sericea establishment success. Future research on: (a) how the distribution and local density of L. sericea is responding to fire regimes, climate change and recent land-use changes, (b) water use of L. sericea to predict the potential impact of the species on water provisioning at the landscape scale, (c) insect herbivory release on L. sericea due to global warming, (d) changing farming practices and restoring Southern Eland population as the original large mammal that controlled L. sericea, s hould be a priority to guide the management of L. sericea. [ABSTRACT FROM AUTHOR]
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- 2024
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16. Do plants respond to multi‐year disturbance rhythms and are we missing the beat?
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Vermeire, Lance T., Reinhart, Kurt O., and Ott, Jacqueline
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SPRING , *FIRE testing , *PLANT communities , *BIOMASS , *ECOSYSTEMS , *GRASSLANDS - Abstract
Disturbance seasonality and return interval can create complex interactions of direct and indirect effects on species and ecosystems. Fire is a key grassland disturbance, yet long‐term research examining seasonality and return intervals is limited. A 15‐year experiment testing combinations of fire seasonality (summer, fall, spring) and return interval (2, 3, 6‐year) plus non‐burned controls was conducted in northern mixed prairie to evaluate effects on the plant community. Hesperostipa comata is a native C3 bunchgrass and dominant species in northern mixed prairie and previously observed to be fire‐sensitive. Current‐year aboveground biomass results were generally counter to expectations based on short‐term research. Fire increased H. comata biomass with a strong, rhythmic response pattern to a specific fire seasonality‐return‐interval combination (fall fire at 3‐year return intervals) that periodically increased biomass to more than three times that with no fire. Through the first four post‐fire growing seasons, biomass with summer, fall and spring fire across return intervals was 41, 89 and 93% of that with no fire. Afterward, no fire combination produced less biomass than no fire and recurring patterns emerged with large increases in biomass, particularly with fall fire at 3‐year intervals. Peak biomass years were regularly two growing seasons after 3‐year fall fire and occurred across wet, near‐average and dry conditions. We hypothesize that productivity responses were driven by the combination of demographic processes of seedling recruitment and synchronization of multiple tiller age classes. Because short‐term negative effects were reversed and regular patterns only emerged 5 years after study initiation, more long‐term research evaluating fire regimes is recommended to expand upon tests of individual factors over short periods. This suggestion is based on fire research, but likely applies to multiple forms of disturbance and demonstrates how demographic processes can inform responses for individual species and larger ecosystem functions, such as productivity. [ABSTRACT FROM AUTHOR]
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- 2024
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17. In the Heat of the Moment: Testing Fire-Protective Covers for Mitigating Damage to Large Historic Inventories.
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Jernæs, Nina Kjølsen and Fjellgaard Mikalsen, Ragni
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FIRE fighters , *CULTURAL property , *INVENTORIES , *NORWEGIANS - Abstract
Since the 1990s, the Norwegian management for cultural heritage has increased its focus on finding effective solutions for protecting Norway's wooden cultural heritage from fire damage. The medieval churches in general, including the wooden stave churches, with their interiors and inventories, are of special interest. However, the usefulness of protecting valuable interiors and inventories when fighting fire has been questioned. An experiment was carried out to find manageable solutions for protecting large inventories by using fire covers in case of fire. An experiment using seven commercially available products was conducted by fire fighters to investigate whether these products could protect historic interiors from water and fire. The preliminary results show that it is possible to find manageable, large format covers for the protection of large, immovable historic inventories. [ABSTRACT FROM AUTHOR]
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- 2024
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18. Rapid barrier estuary infill in a geologically-constrained setting: Aireys Inlet/Painkalac Creek, Victoria, Australia.
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Kennedy, David M., McSweeney, Sarah L., Rogers, Ashley, Tong, Colin, and Goethel, Rory
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SILLS (Geology) , *BEDROCK , *PALYNOLOGY , *INTERTIDAL zonation , *SEA level , *ESTUARIES - Abstract
The Holocene infill of an intermittently open-closed barrier estuary (Painkalac Creek/Aireys Inlet) was examined on the southern margins of Australia, through aerial LiDAR, coring, sedimentology, radiocarbon dating and pollen analysis. It is found that almost all the accommodation space within the estuary has been occupied, with a thick sequence (>9 m) of sediments being deposited rapidly soon after flooding by the sea. The rate of sedimentation was 4.8 mm/year which closely matches the rate of sea level rise (4.5 mm/year) during the 1200 year period that the estuary infilled, from around 8000–6800 years ago. The evidence of estuarine deposition above the elevation of the modern intertidal zone provides significant further evidence for the presence of the mid-Holocene highstand sea level in this relatively unstudied part of the Australian coast. The pattern of infill departs from the traditional barrier evolution models. The first phase of infill was likely tide dominated with subtidal sand shoals being found landward of a subtidal bedrock sill. Once a beach-barrier sequence formed, the estuary infilled in a more traditional manner, with lateral progradation of a flood tide delta and central mud basin infill. The barrier estuary of Painkalac Creek therefore has undergone a complex evolutionary history, characterised by a change in process dominance from classic tidal to wave-dominated form. Infill occurred in a keep-up (or fast catch-up) mode, with geological control occurring in regard to the presence of an intertidal bedrock sill at the mouth of the estuary. [ABSTRACT FROM AUTHOR]
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- 2024
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19. Effect of abrupt post‐fire ash inputs on water quality and the phytoplankton community in lentic freshwaters.
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de Jesus, Gabriel Sampaio, Machado, Karine Borges, de Carvalho, Priscilla, Nabout, João Carlos, and Bortolini, Jascieli Carla
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WATER quality , *GREEN algae , *ELECTRIC conductivity , *DESMIDIACEAE , *DIATOMS - Abstract
One of the major threats to biodiversity is changing fire regimes, particularly increasingly frequent fires, especially during the dry season. However, studies on the direct and indirect effects of fire on biotic responses in aquatic ecosystems are still scarce. In this study, we investigated how water quality and phytoplankton community structure were affected by different ash concentrations from burning vegetation of a tropical savanna.We used a microcosm experiment to simulate the aquatic ecosystem with different ash concentration scenarios and evaluated the water quality and the composition, richness and density of phytoplankton over time.We found increased total phosphorus and ammoniacal nitrogen concentrations after ash addition, in addition to changes in electrical conductivity. We identified 242 phytoplankton taxa throughout the experiment and identified changes in species composition among treatments. We identified changes in the taxonomic richness of total phytoplankton, green algae and desmids over time. The density of total phytoplankton, diatoms, green algae, desmids and cyanobacteria also changed over time.Our results suggest that ash from terrestrial fires affects water quality and phytoplankton communities depending on the proportion of ash input. Our results serve as a basis for further investigations of the effects of fire on abiotic conditions in aquatic ecosystems and their communities over long periods of time. Finally, longer‐term experiments are needed to evaluate delayed responses by the phytoplankton community. [ABSTRACT FROM AUTHOR]
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- 2024
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20. Buckling and Critical Temperature Prediction Formulas of Restrained H-Section Steel Columns in Fire.
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Chen, Zhengrong and Jiang, Binhui
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IRON & steel columns , *CRITICAL temperature , *PROGRESSIVE collapse , *FIRE prevention , *NUMERICAL analysis , *RESTRAINT of patients - Abstract
Buckling and critical temperatures of steel columns are crucial parameters for structural fire safety design. However, the existing simplified design methods for buckling or critical temperature are based on column models with either pin ends or with large rotational restraints. Their applications on steel columns with limited rotational restraint stiffness ratios—the ones smaller than the critical rotational restraint stiffness ratio—is questionable. In this paper, parametric analyses on a validated numerical column model with rotational restraint stiffness ratio varying from 0.0001 to 10.0 were conducted. The effects of slenderness ratio, load ratio, and axial restraint stiffness ratio were also considered. Results show that for steel columns with limited rotational restraint stiffness ratios, prediction errors of existing simplified design methods were significant. Following the parametric analyses, new prediction formulas of buckling temperature and critical temperature are proposed for H-section steel columns. Results of proposed formulas aligned closely with those of parametric analyses in the full range of considered parameters. Furthermore, the proposed formulas were also validated by test results in the literature. [ABSTRACT FROM AUTHOR]
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- 2024
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21. A chaos theory view of accidental dwelling fire injuries.
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Taylor, M., Francis, H., Fielding, J., Jarman, I., and Etchells, T.
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INHALATION injuries ,CHAOS theory ,STATISTICS ,SMOKE ,WOUNDS & injuries - Abstract
In this article, we examine a chaos theory view of accidental dwelling fire injuries using data from a UK fire and rescue service over a 10‐year period. Although chaos theory could not predict if or when a fire injury will occur for a given individual, chaos theory provided further information above and beyond the typical statistical analyses undertaken by fire and rescue services in terms of identifying pattern repetitions, interconnectedness of circumstances and sensitivity to initial conditions relating to the circumstances of accidental dwelling fire injuries. Householder behaviours such as attempting to tackle the fire or being under the influence of alcohol or drugs were the most prevalent circumstances relating to fire injury over the period studied. Proportions of smoke/toxic fumes inhalation injuries and injuries sustained attempting to fight the fire compared to the overall numbers of fire injuries per year showed pattern repetition over the period studied. In terms of interconnectedness, although there were roughly equal numbers of male and female fire injuries overall, the likelihood of an alcohol‐/drug‐related fire injury or a fire injury resulting from attempting to put out a fire was strongly connected with the gender of the householder involved. [ABSTRACT FROM AUTHOR]
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- 2024
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22. Predicting the Residual Compressive Strength of Concrete Exposed to Elevated Temperatures Using Interpretable Machine Learning.
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Noman, Muhammad, Khattak, Afaq, Alam, Zeshan, Yaqub, Muhammad, and Noroozinejad Farsangi, Ehsan
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CONCRETE construction ,HIGH temperatures ,COMPRESSIVE strength ,MACHINE learning ,RANDOM forest algorithms ,EFFECT of temperature on concrete - Abstract
The accurate prediction of residual compressive strength (RCS) of concrete plays a critical role in assessing concrete constructions' safety and structural integrity following exposure to elevated temperatures. Existing ensemble models exhibit RCS prediction capabilities, yet they are constrained by their opaque nature. This research endeavors to develop an intelligible model for RCS by employing five ensemble machine-learning models, namely, random forest (RF), adaptive boosting (AdaBoost), gradient boosting (GBoost), light gradient boosting (LGBoost), and extreme gradient boosting (XGBoost), and integrating Shapley additive explanations (SHAP) to ascertain the precise importance of each input variable in forecasting the RCS of concrete under elevated temperature conditions. The input variables encompass concrete type, compressive strength, aggregate type, water-cement ratio, heating type, heating rate, maximum core temperature, and cooling type. Model performance is appraised using established performance metrics such as mean absolute error (MAE), mean squared error (MSE), root-mean squared error (RMSE), and coefficient of determination (R2). The analytical results exhibit the efficacy of employing machine-learning models in accurately predicting the RCS of concrete under elevated temperature conditions. Among the implemented models, XGBoost demonstrated the highest performance, yielding an R2 value of 0.876, closely trailed by the LGBoost model at 0.871. The SHAP analysis elucidates the crucial role of core temperature, water-cement ratio, heating rate, and compressive strength in determining the RCS of concrete. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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23. Thermal response of timber connections using densified wood dowels under fire.
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Khelifa, Mourad, Tran, Trong Tuan, Khennane, Amar, Oudjene, Marc, and Rogaume, Yann
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DOWELS ,TIMBER ,THERMAL properties ,NUMERICAL analysis ,BIOMASS ,THERMOGRAVIMETRY - Abstract
A new type of timber connection using densified wood dowels is being developed and tested. The procedure involves inserting these densified dowels into pre-drilled holes. As this connection technique is in its early stages, a unique design approach is necessary, considering the impact of temperature variations. The primary goal is to characterize the thermal behaviour of these connections under elevated temperatures. The study employs an experimental approach, complemented by numerical analysis, innovatively applying kinetic models, commonly used for investigating heat-related biomass characteristics, to wood. The method requires the use of thermogravimetric analysis to identify the kinetic parameters. The proposed pyrolysis kinetic model has been implemented in the Abaqus/Implicit code via a user subroutine UMATHT. The study concludes that using kinetic models enhances accuracy by considering mass loss, a key factor influencing thermal properties. Simulation successfully replicates temperature distribution and charred layer thickness, crucial for designing timber structures. [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
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24. Damage analysis and assessment of concrete T-girder bridge based on fire scene numerical reconstruction.
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Chen, Yingzhen, Xu, Zhaofeng, Huang, Yonghui, Xu, Qingyuan, and Rao, Rui
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COMPUTATIONAL fluid dynamics ,FINITE element method ,CONCRETE bridges ,TEMPERATURE distribution ,CONCRETE analysis - Abstract
Fire is a sporadic disaster of concrete bridges, with diverse fire environments and complex damage mechanisms. Accurately evaluating the damage situation of concrete bridges after a fire is exceedingly challenging. This study formulates a damage analysis and assessment method based on the step-by-step and progressively deepening working principle. The method relies on fire scene numerical reconstruction and encompasses key technical aspects, including bridge detection and analysis during the fire incident, fire scene numerical reconstruction, and subsequent bridge damage assessment. Building upon these principles, the study utilizes results from the detection and analysis of the concrete T-girder bridge during a fire incident to establish Computational Fluid Dynamics (CFD) and Finite Element Method (FEM) models for the numerical reconstruction of the fire scene. These models enable the calculation of varying temperature distributions and the evolution of the bridge under fire. Compared with the parameters obtained through the ISO834 method, the numerical reconstruction approaches not only enhances the accuracy of replicating the bridge combustion process but also enables the extraction of temperature field distribution patterns within the bridge fire space and its concrete components. [ABSTRACT FROM AUTHOR]
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- 2024
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25. Monitoring of historical structural materials with computed tomography.
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Csorba, Kristóf, Kapitány, Kristóf, Cimer, Zsolt, Hlavička, Viktor, Biró, András, and Lublóy, Éva
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MATERIALS science , *PRESTRESSED concrete , *CONSTRUCTION materials , *COMPUTED tomography , *STRUCTURAL health monitoring , *DETERIORATION of concrete - Abstract
Computed tomography (CT) is an excellent tool to solve certain engineering problems connected to material science (such as sulfate swelling, internal degradation due to freezing, and alkali silicate swelling) and to understand specific processes (frost peeling, acid action). Albeit borne and mostly used in the medical domain, CT is increasingly used in the examination of the internal structure of building materials, where degradation processes occur to the detriment of their mechanical performance and durability. This paper presents five engineering problems concerning concrete freezing and thawing, concrete at high temperatures, timber charring, spalling in asbestos‐cement pipes, and deterioration in prestressed concrete pipes due to the corrosion of metallic inserts. In each case, the degradation processes are monitored via CT, something that may be crucial in the renovation and preservation of historical structures. [ABSTRACT FROM AUTHOR]
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- 2024
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26. Non‐native invasive plants in tropical dry forests: a global review of presence, impacts, and management.
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Hardy, Nora G., Kuebbing, Sara E., Duguid, Marlyse C., Ashton, Mark S., Sheban, Karam C., Inman, Seth E., and Martin, Meredith P.
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SCIENTIFIC literature , *TROPICAL dry forests , *TROPICAL ecosystems , *AGRICULTURE , *ECOLOGICAL disturbances , *INVASIVE plants - Abstract
Tropical dry forests (TDF) are among the most‐threatened terrestrial ecosystems, experiencing ongoing conversion to agricultural fields, pasture, and human settlements. Human disturbances are often precursors to invasion of ecosystems by non‐native species, but research on invasion patterns in tropical ecosystems is sparse, and there is no comprehensive synthesis of invasive species in TDF. We conducted a review of published scientific literature to catalog and synthesize information about invasion by non‐native plants in TDF ecosystems across the globe, drawing out patterns in the invasion of these ecosystems. We found that 130 invasive plant species were documented as present in TDF, but only 25 of these species were mentioned in three or more articles. Almost all 25 of these more‐studied invasive species—mostly pasture grasses, woody legumes, and climbers—have been intentionally cultivated for agricultural or ornamental purposes. Many of these plants are native to open‐canopy savanna or forest edge habitats and benefit from human‐altered disturbance regimes (burning, grazing, and fuelwood and timber harvesting) of TDF fragments within agricultural landscapes. Field studies show that management approaches incorporating invasive removal, native plantings, and reduction in agricultural disturbance (e.g. ungulate fencing and fire control) simultaneously are often the most successful at reducing invasive plant cover. However, management studies in TDF have focused on a limited number of invasive species, and most were conducted in India and Hawaii. Global differences in TDF soils, natural fire regimes, and historic and current land use by humans influence modern biogeographic patterns of invasion and the feasibility of restoration options. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
27. Pressure–impulse diagrams of RC beams considering fire–blast interaction.
- Author
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Colombo, Matteo and Martinelli, Paolo
- Subjects
- *
CONCRETE beams , *BLAST effect , *INFRASTRUCTURE (Economics) , *REINFORCED concrete - Abstract
When analyzing military, defense, or structures/infrastructures deemed critical, explosion‐induced actions—often associated with malicious actions—play a significant role. The combined effect of a blast and fire is not uncommon: in fact, an explosion can be the extreme consequence of a fire or vice versa, a fire can occur as the result of an explosion. Although advanced numerical approaches can be a proper solution for analyzing critical structures and infrastructures subjected to accidental actions, their complexity makes these approaches unsuitable for the analysis of ordinary buildings or even for the preliminary design of structures. A pressure–impulse diagram is an easy and common tool that can be adopted to verify the safety of structural members for a wide range of blast scenarios even considering the damage caused by a previous fire. This study aims to compare different approaches that can be adopted for the construction of pressure–impulse diagrams of reinforced concrete structures subjected to a blast and a blast preceded by fire. Taking as a reference case a statically indeterminate beam with three supports, this work presents the influence of the methods of analysis on the safety level assessed through pressure–impulse diagrams. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
28. Fire season and time since fire determine arbuscular mycorrhizal fungal trait responses to fire.
- Author
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Hopkins, Jacob R., McKenna, Thomas P., and Bennett, Alison E.
- Abstract
Background and aims: Arbuscular mycorrhizal (AM) fungi are common mutualists in grassland and savanna systems that are adapted to recurrent fire disturbance. This long-term adaptation to fire means that AM fungi display disturbance associated traits which should be useful for understanding environmental and seasonal effects on AM fungal community assembly. Methods: In this work, we evaluated how fire effects on AM fungal spore traits and community composition vary with fire season (Fall vs. Spring) and time since fire. We tested this by analyzing AM fungal spore traits (e.g., colorimetric, sporulation, and size) from a fire regime experiment. Results: Immediately following Fall and Spring fires, spore pigmentation darkened (became less hyaline); however, this trait response was not linked to fire driven changes in spore community composition and likely implies a plastic spore pigmentation response to fire. Six months after Fall fires, spores in burned plots were lower in volume, produced less color rich pigment, and had higher sporulation rates, and these differences in spore traits were associated with shifts in AM fungal spore communities demonstrating environmental filtering. Conclusion: Fire drove plastic and longer-term changes in AM fungal spore traits and community assembly that varied with fire season (stronger effects in Fall) and time since fire. This demonstrates the utility of applying trait-based approaches to microbial community assembly, and the importance of considering changes in community assembly across time. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
29. 考虑多火灾场景的古城镇消防供水可靠性评估.
- Author
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贾睿, 杜坤, 宋志刚, and 张健
- Abstract
Given the current situation of frequent fire accidents in Yunnan Province, assessing the fire safety of ancient towns is a task of great practical significance for the safety of people's lives and property and the protection of cultural heritage. The fire failure indices is proposed to screen buildings and combinations with high fire failure risk. Firstly, the fire flow calculation method of the US Federal Insurance Office was used to assess the fire water demand of important individual buildings in the event of a fire. Secondly, a hydraulic model was then constructed to assess the water supply capacity of the fire network. Finally, the building fire failure indices is calculated to identify hazardous buildings and hazardous combinations. The proposed algorithm is applied to the fire pipe network of Dayan Old Town in Lijiang City, Yunnan Province. The results show that the failure index of a single fire scenario is not only related to the pipe diameter of the pipe, the number of fire hydrants near the building and the fire resistance class of the building, but also depends on the location of the building. With the increase of the number of fire scenarios, the failure index of each building shows a different degree of increase, and the maximum can be more than 30%. It is recommended to install additional fire hydrants near the fire pipe network in the area with fewer fire hydrants in order to increase the fire water supply capacity and optimise the fire fighting facilities in buildings far from water sources. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
30. Modernisation of Fire Protection Education in Elementary Schools.
- Author
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Dzermansky, Martin, Snopek, Lukas, and Drabikova, Dora
- Subjects
- *
ELEMENTARY school teaching , *SCHOOL fires & fire prevention , *ELEMENTARY education , *MOBILE operating systems , *MOBILE apps - Abstract
The article deals with the issue of teaching fire protection in elementary schools in the Czech Republic. The area of fire protection is one of the key areas that everyone should be familiar with and it is important to teach children how to prevent fires and how to face fires in case of danger. Thus, this article analyses the current approaches of elementary schools to teaching fire protection and compares the data obtained with approaches in teaching abroad. The obtained comparison is complemented by conducting a questionnaire survey, which underpins the current trends and possibilities of modernising the teaching itself. The results are presented in the form of graphs and the design of a potential application based on the presented mobile applications available on common mobile platforms. The conclusions of the study are summarised in the final chapter, which points to the need to expand fire protection education and the use of modern technologies. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
31. Interannual Variability in Seed Germination Response to Heat Shock in Cistus ladanifer.
- Author
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Luna, Belén
- Subjects
- *
SEED dormancy , *SEED viability , *PHENOTYPIC plasticity , *MEDITERRANEAN climate , *GERMINATION - Abstract
Mediterranean climates, characterised by hot and dry summers, have predictable fire regimes, and many species with physical seed dormancy (PY) thrive after wildfires. While it is well known that PY is released after heat shock in these species, intraspecific variation in seed response to heat is less understood. This research explores, for the first time, the variability in the traits of Cistus ladanifer seeds from the same central Spain population over eight years. It examines seed germination and viability under different heat shocks and the relationships among seed traits and climatic variables. While the response to heat shock remained constant over the years studied, achieving the highest germination percentages after heat shock at 100 °C, seed germination varied between years, and environmental conditions affected seed traits. Seed moisture content was negatively correlated with the maximum summer temperatures, and seed viability was positively related to annual precipitation. Germination at 100 °C was lower in warmer years as more seeds did not break their PY. In conclusion, despite the fact that PY appears to be genetically determined, it also depends on the environmental conditions experienced by the mother plant. This interannual phenotypic variability may help Cistus ladanifer to cope with the increasingly unpredictable conditions imposed by climate change. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
32. The Influence of Hydrogen Concentration on the Hazards Associated with the Use of Coke Oven Gas.
- Author
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Klejnowski, Mateusz and Stolecka-Antczak, Katarzyna
- Subjects
- *
FLAMMABLE gases , *COKE (Coal product) , *GAS explosions , *POISONS , *CARBON monoxide - Abstract
Coke oven gas (COG), as a by-product of the coking process and a mixture with a high hydrogen content, is an important potential component of the sustainable economy of the coking industry. Ongoing studies and analyses are looking at many opportunities for the utilization of coke oven gas, including for the production of hydrogen, methanol or other chemicals. However, it is important not to forget that all processes for the utilization of this gas may pose a potential hazard to humans and the environment. This is due to the physicochemical properties of COG and the content of flammable gases such as hydrogen, methane or carbon monoxide in its composition. Potential hazardous events are also related to the content of toxic substances in the composition of coke oven gas. The publication focuses on the occurrence of a fire or explosion as a result of the uncontrolled release of purified coke oven gas from the installation. The potential hazard zones associated with the occurrence of these phenomena are presented concerning different levels of hydrogen concentration in coke oven gas and the influence of selected factors on the range of these zones. Zones related to human deaths due to fire of coke oven gas reached a maximum range of about 130 m from the site of the failure, depending on the gas composition, level of damage and parameters of the installation. Zones related to human deaths due to the explosion of the coke oven gas did not occur. The zone related to the injury of humans as a result of the COG explosion reached a maximum range of about 12 m. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
33. Stress–strain characteristics of fire‐exposed recycled coarse aggregate concrete.
- Author
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Tariq, Faraz, Hasan, Hamza, and Bhargava, Pradeep
- Subjects
- *
MINERAL aggregates , *HIGH temperatures , *ELASTIC modulus , *BOND strengths , *TENSILE strength - Abstract
Concrete sustainability and performance under extreme conditions are of growing interest in construction engineering. This study delves into the influence of recycled coarse aggregate (RCA) content and elevated temperatures on normal‐strength concrete containing RCA. Five different concrete compositions, featuring varying content of RCA (ranging from 0% to 100%), were examined. The heating and subsequent cooling followed the ISO‐834 temperature–time graph up to 800°C. The primary objective was to evaluate residual properties, including the stress–strain behavior, compressive and tensile strength, secant elastic modulus, peak strain, and bond strength of RCA concrete. The findings reveal a consistent decrease in both strength and stiffness parameters of RCA concrete with rising temperatures, while peak strain exhibits a rapid increase at elevated temperatures. Interestingly, RCA content had a negligible impact on the relative deterioration of high‐temperature exposed RCA concrete compared to that at ambient conditions. Moreover, the bond behavior closely resembled that of natural aggregate concrete when used in moderate proportions. Degradation models based on regression analysis of the data were used to quantify the bond strength reduction for RCA‐based concrete and the slip of rebar concerning various temperatures. Importantly, these models demonstrated consistency with those applicable to conventional concrete. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
34. Semiempirical Equations to Evaluate Maximum Deflection in RC Beam and Column under Fire.
- Author
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Baheti, Akshay, Lange, David, and Matsagar, Vasant
- Subjects
- *
CONCRETE beams , *COMMON misconceptions , *PEARSON correlation (Statistics) , *REINFORCED concrete , *PERFORMANCE-based design , *FIRE testing - Abstract
Many design regulations around the globe rely on member deflection as a governing criterion for resistance assessment in fire. The deflection evaluation in fire is generally achieved by conducting expensive experiments or computationally expensive finite-element analyses. This often restricts practicing engineers from using robust performance-based design philosophy for typical structures. Instead, they rely on objective design guidelines, often resulting in inefficient sizes of reinforced concrete (RC) members. Therefore, semiempirical relations are derived in the current study to determine the maximum deflection of the RC beam and RC column in a fire. Three separate end conditions are considered within the beam category: fixed-fixed beam, propped cantilever beam, and simply supported beam. Plausible variables are first identified that could affect the overall deflection of the member, and their proportionality is subsequently determined by performing one-on-one regression analysis. Furthermore, these relations are developed in terms of the most suitable fire intensity measures derived from the literature, which makes them applicable irrespective of the type of fire framework. The credibility of the deflection equations is validated through visual analysis followed by the three popular error indicator parameters, namely, Pearson's correlation coefficient, relative root-mean squared error (RRMSE), and performance index. Results indicated that all deflection equations accurately predict the RC member behavior under fire. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
35. Fire favours the native bee community in a semi‐arid ecosystem.
- Author
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Castañeda González, Alejandra, Salazar Ceseña, Mario, del Val, Ek, Macip‐Ríos, Rodrigo, and Ceccarelli, Fadia Sara
- Subjects
- *
RESOURCE availability (Ecology) , *ECOLOGICAL disturbances , *FIRE management , *SPECIES diversity , *PLANT species - Abstract
Fire is a common and frequent disturbance in Mediterranean ecosystems, affecting the diversity and dynamics of native bee communities by modifying the distribution and availability of the resources that bees require to forage and nest. Previous studies have found changes in bee diversity depending on the time since the last fire, with increases in species diversity in the early stages postburn.Using a chronosequence of plots with different times since the last fire in the Mediterranean‐climate chaparral of Baja California, Mexico, we estimated changes in overall abundance, richness, diversity and species composition of the native bee community.Bee abundance and richness were higher at recently burned plots and gradually decreased, but Hill–Shannon and Hill–Simpson diversities did not change over the chronosequences. Nearby plots (in the same locality) of different stages were more similar in composition than distant plots (in different localities) of a similar stage, suggesting a spatial correlation. Plant species richness increased after fires. Bare soil was also greater on recently burned patches and may facilitate nesting resources. The number of bees was positively correlated to plant richness.Our results highlight the importance of fire as a natural disturbance structuring the bee community in the Mediterranean chaparral of Baja California.Furthermore, our results are relevant for future conservation plans since fire management (i.e., prescribed fires) could improve conditions for sustaining greater bee richness and abundance. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
36. PROJETO DE SEGURANÇA CONTRA INCÊNDIO E PÂNICO - PSCIP: ESTUDO DE CASO EM POSTO DE COMBUSTÍVEIS NA CIDADE DE MANAUS.
- Author
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dos Santos da Silva, Keila, Gomes dos Santos Gonçalves, Paula Glysia, and Nogueira Marques Pinheiro, Érika Cristina
- Subjects
FIRE prevention ,REGULATORY compliance ,SECURITY systems ,SERVICE stations ,SYSTEM safety - Abstract
Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2024
- Full Text
- View/download PDF
37. Quantifying Post‐Colonial Peat Carbon Loss From a Drained Forested Peatland, Great Dismal Swamp National Wildlife Refuge, USA.
- Author
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Jones, Miriam C., Willard, Debra A., Wurster, Frederic C., and Huber, Molly
- Subjects
CLIMATE change ,DITCHES ,SURFACE of the earth ,WILDLIFE refuges ,CARBON cycle ,CARBON offsetting ,PEATLAND restoration - Abstract
Peatland carbon storage is increasingly threatened by the combination of land‐use change and climate variability, though carbon losses from land‐use changes that span centuries are difficult to quantify, particularly in systems where little undisturbed area remains. Here we use a combination of vegetation change, fire history, and calculations of excess ash mass to quantify carbon loss in the Great Dismal Swamp National Wildlife Refuge (GDS NWR), USA, a highly impacted oligotrophic temperate peat swamp. Our results indicate that ditch construction that began in the Colonial Era in the late 1700s and continued into the mid‐20th century across the swamp resulted in shifts from cypress‐tupelo swamps to a combination of maple‐gum and pine pocosin forests, consistent with drying surface conditions. Two large smoldering fires (2008, 2011) that were exacerbated by surface drainage, shifted vegetation from swamp to marsh, consumed peat over 25 km2, and caused losses of 1.05–1.34 Tg C due to peat burning. Across the Refuge as a whole, up to 48.2 Tg C has been lost to peat oxidation since ditch construction. Both stocks and rates of carbon loss remain higher than post‐disturbance accumulation across most of GDS NWR, suggesting that existing efforts to block drainages to elevate water tables may not be enough to offset carbon losses. Rewetting heavily impacted surface peats may reduce peat oxidation and carbon loss, and shift vegetation toward hydrologic conditions preferred by pre‐disturbance cypress‐tupelo swamps. Plain Language Summary: Peatlands sequester a globally significant pool of carbon despite covering only 3% of the terrestrial earth's surface. However, this carbon can be released to the atmosphere as the greenhouse gases carbon dioxide and methane due to changes in climate and land use. In this study we quantify carbon loss from Great Dismal Swamp, a temperate peat swamp with a history of drainage that began with George Washington in the late 18th century. Using ash content as a proxy for peat loss, we found that Great Dismal Swamp has lost a substantial amount of carbon (∼50 million metric tons) since Colonial‐era ditching, with more than 1 million metric tons lost from two recent catastrophic smoldering peat fires. Our calculations suggest that the swamp continues to lose carbon, despite efforts to slow water loss from nearly 240 km of drainage ditches constructed over the last >200 years. More aggressive mitigation methods may be needed to return the Great Dismal Swamp to a carbon sink, an important consideration as the United States aims to reach carbon neutrality in the coming decades. Key Points: Excess ash mass is used to quantify a loss of ∼50 Tg of carbon in a temperate peat swamp since drainage began in the late 1700sMore than 1 Tg of carbon and 50–75 cm of peat were consumed in two recent fires in Great Dismal SwampCarbon loss in the peat swamp is continuing, despite management efforts to reduce water loss from ∼240 km of drainage ditches [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
38. Strength Evaluation of CFRP-Strengthened RC Slab-Beams System by Load Test to Satisfy the Safety Requirements: A Case Study.
- Author
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Hanoon, Ammar N., Abdulhameed, Ali A., Al‐Zuhairi, Alaa Hussein, Ansari, Mohammad, Al Zand, Ahmed W., Banyhussan, Qais S., and Abdulhameed, Haider A.
- Subjects
REINFORCED concrete testing ,CARBON fiber-reinforced plastics ,CRACKING of concrete ,FINITE element method ,FIRE testing - Abstract
The primary goal of in-situ load testing is to evaluate the safety and performance of a structural system under particular loading conditions. Advancements in building techniques, analytical tools, and monitoring instruments are prompting the evaluation of the appropriate loading value, loading process, and examination criteria. The procedure for testing reinforced concrete (RC) structures on-site, as outlined in the ACI Building Code, involves conducting a 24-h load test and applying specific evaluation criteria. This article detailed a retrofitting project for an RC slab-beams system by utilizing carbon fiber-reinforced polymer (CFRP) sheets to strengthen the structure following a fire incident. The RC structure showed indicators of deterioration, including deflections, concrete cracking, and concrete spalling in some zones. Whereas, a detailed presentation of the strengthening procedure as well as its evaluation, rationale for the loading procedure, instrumentation needs, assessment criteria, and outcomes of the field testing. The study concentrated on assessing the structure of the RC slab-beam system with widespread cracking in both the positive and negative moment areas. The finite element model was created and examined to help with the load test design, and it confirmed the field findings considerably. The proposed finite element (FE) model demonstrated a reduced estimation of net deflection value in comparison to the corresponding actual values. It maintained a highly acceptable mean value of 0.843 and a small deviation limit of 6.8%. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
39. Insights into Boreal Forest Disturbance from Canopy Stability Index.
- Author
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Mackey, Brendan, Hugh, Sonia, Norman, Patrick, Rogers, Brendan M., and Dellasala, Dominick
- Subjects
CLIMATE change ,FOREST canopies ,LOGGING ,TAIGAS ,FIRE weather ,FOREST fires - Abstract
The world's forests are being increasingly disturbed from exposure to the compounding impacts of land use and climate change, in addition to natural disturbance regimes. Boreal forests have a lower level of deforestation compared to tropical forests, and while they have higher levels of natural disturbances, the accumulated impact of forest management for commodity production coupled with worsening fire weather conditions and other climate-related stressors is resulting in ecosystem degradation and loss of biodiversity. We used satellite-based time-series analysis of two canopy indices—canopy photosynthesis and canopy water stress—to calculate an index that maps the relative stability of forest canopies in the Canadian provinces of Ontario and Quebec. By drawing upon available spatial time-series data on logging, wildfire, and insect infestation impacts, we were able to attribute the causal determinants of areas identified as having unstable forest canopy. The slope of the two indices that comprise the stability index also provided information as to where the forest is recovering from prior disturbances. The stability analyses and associated spatial datasets are available in an interactive web-based mapping app. that can be used to map disturbed forest canopies and the attribution of disturbances to human or natural causes. This information can assist decision-makers in identifying areas that are potentially ecologically degraded and in need of restoration and those stable areas that are a priority for protection. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
40. PHOSPHATE FERTILIZATION IMPROVE PRODUCTIVITY AND CHEMICALBROMATOLOGICAL COMPOSITION OF LEAF BLADE OF UNBURNED PASTURE.
- Author
-
da Silva, Luiz Carlos and de Almeida Lobo, Francisco
- Subjects
FEED analysis ,FIRE management ,COMPOSITION of leaves ,AGRICULTURE ,FOLIAR feeding - Abstract
Copyright of Environmental & Social Management Journal / Revista de Gestão Social e Ambiental is the property of Environmental & Social Management Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2024
- Full Text
- View/download PDF
41. Elevated Temperature Effects on FRP–Concrete Bond Behavior: A Comprehensive Review and Machine Learning-Based Bond Strength Prediction.
- Author
-
Salameh, Aseel, Hawileh, Rami, Safieh, Hussam, Assad, Maha, and Abdalla, Jamal
- Subjects
MACHINE learning ,GLASS transition temperature ,BOND strengths ,FIBER-reinforced plastics ,HIGH temperatures - Abstract
Because of their improved properties, FRP composites are vastly used in the strengthening of aged concrete infrastructures. However, it has been observed that their performance is highly compromised when exposed to high temperatures, as expected during fire incidents, which critically affects FRP–concrete bond behavior, hence affecting the overall efficiency of the strengthening system. This paper critically presents the available literature concerning the degradation of bond strength between FRP systems with concrete substrates due to increased temperatures. Both analytical and numerical bond–slip models developed for the prediction of bond strength degradation under such conditions are reviewed. A generally confirmed fact is that exposure to high temperatures, especially those reaching glass transition temperature (T
g ) for epoxy adhesives, leads to bond degradation. Therefore, cement mortar-bonded CFRP textiles display better performance in fire endurance. This present paper also utilizes machine learning algorithms for the prediction of bond strength under elevated temperatures based on an experimental database of 37 beams. The nonlinear relationships and variable interactions in the developed model provide a reliable method for the estimation of bond strength with reduced extensive experimental testing, where the critical role of temperature in bond behavior is identified. This paper emphasizes the use of advanced predictive models to ensure the durability and safety of FRP-strengthened concrete structures in thermally challenging environments. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
42. Energetics explain predator occurrence and movement in pyrodiverse landscapes.
- Author
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McGinn, Kate, Zulla, Ceeanna, Wright, Marilyn, Wilkinson, Zachary, Dotters, Brian, Roberts, Kevin, Keane, John, Peery, M. Zachariah, and Jones, Gavin M.
- Abstract
Context: Fire-adapted species have evolved to exploit resources in heterogenous landscapes that presumably maximize energy acquisition and minimize energetic expenditure. However, limited empirical work exists demonstrating the explicit energetic mechanisms that drive such adaptive responses to fire across diverse landscapes. Objectives: The California spotted owl (Strix occidentalis occidentalis) appears to benefit from landscape heterogeneity and preferentially uses smaller patches of severely burned forest, a behavior that has been hypothesized as adaptive. Here, we investigate empirical support for this hypothesis. Methods: We leveraged high-resolution GPS tracking and nest video monitoring to examine the hunting success, movement, and nest provisioning of 34 spotted owls in the Sierra Nevada and San Bernardino Mountains, California across burned and unburned landscapes. Results: Regardless of time since fire, individuals avoided foraging directly within moderately or severely burned patches. 1 to 2 years post-fire, individuals had more success capturing prey in unburned forest, and the energy individuals spent moving increased with the proportion of high-severity fire and decreased with the proportion unburned forest. Multiple years after a fire, individuals had more success capturing prey, spent less energy moving, and provisioned more energy to nests in landscapes with more low-severity fire. Conclusions: These results support the hypothesis that spotted owls are adapted to fire-prone landscapes and that disturbance events within this region’s natural range of variation can ultimately promote hunting and provisioning. As fires deviate from regional norms across the globe, the negative impacts of fire may become more extreme and long-term benefits of fire may degrade for animals in fire-prone landscapes. Examining the mechanistic impacts of disturbance can allow us to better understand animal responses to rapidly changing landscapes. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
43. Redistribution of debris‐flow sediment following severe wildfire and floods in the Jemez Mountains, New Mexico, USA.
- Author
-
Friedman, Jonathan M., Tillery, Anne C., Alfieri, Samuel, Skaggs, Elizabeth, Shafroth, Patrick B., and Allen, Craig D.
- Subjects
DEBRIS avalanches ,RUNOFF ,SEDIMENT transport ,DIGITAL elevation models ,SPATIAL variation ,WATERSHEDS - Abstract
Severe fire on steep slopes increases stormwater runoff and the occurrence of runoff‐initiated debris flows. Predicting locations of debris flows and their downstream effects on trunk streams requires watershed‐scale high‐resolution topographic data. Intense precipitation in July and September 2013 following the June 2011 Las Conchas Fire in the Jemez Mountains, New Mexico, led to widespread debris flows in the watershed of Rito de los Frijoles. We differenced lidar Digital Elevation Models (DEMs) collected in 2010 and 2016 to map subwatersheds experiencing debris flows and changes in elevation of the trunk stream. Debris flow occurrence was well predicted by previous assessments of debris‐flow hazard; debris flows occurred in 7 of 9 sub‐basins where the debris‐flow hazard was above 60% for the 25‐year rainfall event, and in 0 of 21 basins where debris flow hazard was less than 60%. Debris flows resulted in fan deposition at the confluence with the trunk stream followed by transport during three documented floods. The bed of the 22 km trunk stream increased in elevation by a mean of 0.29 m, but the local change in thalweg elevation was controlled by inputs of water and sediment and longitudinal variation in gradient. Downstream of the mouths of tributaries with debris flows, the thalweg of the trunk stream rose as much as 2 m. Downstream of the mouths of tributaries without debris flows the thalweg of the main stem degraded by as much as 2 m, mobilizing sediment that was then deposited further downstream where the gradient of the trunk stream decreases. In conclusion, the transport of sediment generated by debris flows was predictably related to spatial variation in sediment supply, discharge and gradient. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
44. Characterization of Lithium-Ion Battery Fire Emissions—Part 2: Particle Size Distributions and Emission Factors.
- Author
-
Claassen, Matthew, Bingham, Bjoern, Chow, Judith C., Watson, John G., Chu, Pengbo, Wang, Yan, and Wang, Xiaoliang
- Subjects
PARTICLE size distribution ,HYDROGEN fluoride ,LITHIUM cobalt oxide ,COMBUSTION ,SMOKE - Abstract
The lithium-ion battery (LIB) thermal runaway (TR) emits a wide size range of particles with diverse chemical compositions. When inhaled, these particles can cause serious adverse health effects. This study measured the size distributions of particles with diameters less than 10 µm released throughout the TR-driven combustion of cylindrical lithium iron phosphate (LFP) and pouch-style lithium cobalt oxide (LCO) LIB cells. The chemical composition of fine particles (PM
2.5 ) and some acidic gases were also characterized from filter samples. The emission factors of particle number and mass as well as chemical components were calculated. Particle number concentrations were dominated by those smaller than 500 nm with geometric number mean diameters below 130 nm. Mass concentrations were also dominated by smaller particles, with PM1 particles making up 81–95% of the measured PM10 mass. A significant amount of organic and elemental carbon, phosphate, and fluoride was released as PM2.5 constituents. The emission factor of gaseous hydrogen fluoride was 10–81 mg/Wh, posing the most immediate danger to human health. The tested LFP cells had higher emission factors of particles and HF than the LCO cells. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
45. Integrating an urban fire model into an operational wildland fire model to simulate one dimensional wildland–urban interface fires: a parametric study.
- Author
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Purnomo, Dwi M. J., Qin, Yiren, Theodori, Maria, Zamanialaei, Maryam, Lautenberger, Chris, Trouvé, Arnaud, and Gollner, Michael J.
- Subjects
BUILDING layout ,WILDFIRES ,SURFACES (Technology) ,FLAME ,FLAME spread ,LANDSCAPES ,WILDFIRE prevention - Abstract
Background: Wildland fires that occur near communities, in the wildland–urban interface (WUI), can inflict significant damage to urban structures. Although computational models are vital in wildfires, they often focus solely on wildland landscapes. Aim: We conducted a computational study to investigate WUI fire spread, encompassing both urban and wildland landscapes. Methods: We developed a 1D landscape-scale semi-physical model by integrating a semi-physical urban fire spread model into an Eulerian level set model of wildfire. The model includes ignition and spread through radiation, direct flame contact and ember deposition. Key results: Through a parametric study, we compare the relative change of spread rate from various structural properties and landscape layouts represented by model parameters, highlighting the significant impact of fire-resistant structure materials over surface treatments. Layout configurations play a pivotal role in fire spread, with isolated islands of combustibles effective in reducing spread rate, aligning with existing mitigation strategies. Conclusion: Despite using a 1D domain and limitations on spatial and temporal variability, our model provides insights into underlying phenomena observed in WUI fires and their mitigation. It offers early-stage development of strategies for managing structure materials and landscape layouts. Implications: Our model and findings provide insights into WUI fire dynamics, paving the way for advanced mitigation strategies. This paper introduces a 1D semi-physical model for WUI fires, integrating urban and wildland fire dynamics. It accounts for fire spread via direct flame contact, radiation and embers. Despite limited spatial and temporal variability, the model demonstrates the relative impact of structure properties and landscape layout on WUI fire spread. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
46. A late glacial paleoenvironmental and climate record from the Sierra de Juarez, Baja California.
- Author
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Brunelle, Andrea, Carter, Vachel A., Delgadillo Rodríguez, José, Feagin, Vanessa, and Watt, Jennifer
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- *
LAST Glacial Maximum , *HYDROLOGIC cycle , *GLACIATION , *WATER diversion , *GROUNDWATER recharge - Abstract
Ciénegas are desert wetlands that are strongly correlated with the stability of the hydrologic cycle in arid landscapes. However, these environments are particularly vulnerable to climate change, drought, water diversion, and fire suppression which all have contributed to the degradation of ciénegas along the U.S.-Mexican borderlands. Therefore, identifying the timing of precipitation patterns in this region is of particular interest because of its relationship to many ecological responses of the landscape such as groundwater recharge and fire. Here, we present the first-ever fire paleoenvironmental record from Ciénega Chimeneas, a ciénega complex in the Sierra de Juárez of Baja California. We explore how changes in the amount and seasonality of moisture affected ciénega complexes and fire activity from across the southwestern North American region over the past 45,000 years. Our record suggests that during the late glacial period, 41,000–21,000 cal yr BP, the increase of Larrea and Quercus indicate an increase in summer precipitation. Subsequently, when summer precipitation increased, pollen preservation and pollen accumulation rates (PAR) also increased. Increased vegetation allowed for increased fire activity during the late glacial period. Regionally, most of the comparison sites also indicated wet conditions during the full glacial period. However, around 21,000 cal yr BP, effective moisture decreased resulting in a dramatic change in the vegetation assemblage. Specifically, the summer wet taxa disappeared, while pollen preservation and PAR decreased, suggesting a dry period until ∼14,000 cal yr BP. Little fire activity is recorded after 21,000 cal yr BP, likely due to the absence of fuels. At ∼14,000 cal yr BP, Larrea and Quercus reappear suggesting increased summer precipitation. However, the appearance of Cyperaceae and increases in grasses suggest increased winter precipitation. We suggest that the combination of summer wet and winterwet taxa ∼14,000 cal yr BP represents an increase in ENSO conditions, while the summer moisture controls remained relatively constant. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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47. Effects of different loads of Pinus pinaster Ait. litter and ash on the germination and growth of Cistus ladanifer L.
- Author
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Piñas-Bonilla, Paula, Zavala, Gonzalo, Pérez, Beatriz, and Luna, Belén
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FOREST litter ,CLUSTER pine ,THERMAL shock ,SEED dormancy ,PRESCRIBED burning - Abstract
Key message: Cistus ladanifer L. shows an extraordinary plasticity of germination and growth. Fire promotes the regeneration of C. ladanifer by triggering its germination through thermal shock as well as by enhancing its seedling growth through the addition of ashes. On the contrary, stacking of Pinus pinaster Ait. leaf litter may hinder seedling establishment, at least in the first months after germination. Context: Pinus pinaster Ait. is affected by forest fires in the Mediterranean basin. Its extreme flammability is due to the high spatial continuity together with the massive accumulation of leaf litter. Cistus ladanifer L. is a species which is widely distributed in the west Mediterranean region where it can form vast shrublands and flourish under these pinewoods. Although high temperatures associated with the occurrence of fire trigger germination of C. ladanifer, knowledge on how other factors, such as the presence of litter on the forest floor or the ash left after the fire, influence germination and seedling growth is essential to improve land management plans. Aims: The main objective of this study was to determine the effects of different loads of litter from P. pinaster and ash from their combustion on the germination and growth of seedlings of C. ladanifer. Methods: Two experiments were carried out to assess the effect of heat shock (100 °C for 10 min) and two loads of litter and ash from P. pinaster (control, high and low loads of litter, high and low loads of ash) on the germination and growth after 2 and 4 months of C. ladanifer. Results: Heat shock significantly increased the germination of C. ladanifer. In contrast, the addition of litter and ash had no effect on total germination but affected the growth of the seedlings coming from seeds exposed to heat shock. Litter treatments reduced biomass of 2 months seedlings and ash increased biomass of 4 months seedlings. Conclusion: C. ladanifer is a species favoured by fire in different ways depending on the stage of regeneration. Germination is promoted by heat shock while seedling growth is favoured by ash nutrients. In contrast, pine leaf litter hinders seedling growth, although this effect disappears 4 months after germination. Alternative forest management practices to prescribed fires are recommended if preventing the spread of Cistus is a priority. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
48. Response: Commentary: The role of palaeoecology in reconciling biodiversity conservation, livelihoods and carbon storage in Madagascar.
- Author
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Gillson, Lindsey, Razanatsoa, Estelle, Isandratana Razafimanantsoa, Andriantsilavo Hery, Virah-Sawmy, Malika, and Ekblom, Anneli
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PALEOECOLOGY ,BIODIVERSITY conservation ,FIRE ecology ,LIFE sciences ,CLIMATE change adaptation - Abstract
The authors offer a commentary on the article "Commentary: The role of palaeoecology in reconciling biodiversity conservation, livelihoods and carbon storage in Madagascar" by G. S. Joseph and C. L. Seymour. Topics include the investigation made by the authors on the longevity of open grasslands in the Highlands of Madagascar, reason that binary allocations to forest and/or grassland habitats are problematic, and evidence for the effects of anthropogenic fire according to Seymour and Joseph.
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- 2024
- Full Text
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49. Understanding post‐fire vegetation recovery in southern California ecosystems with the aid of pre‐fire observations from long‐term monitoring.
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Li, Xinyu, Kimball, Sarah, Ta, Priscilla, Schmidt, Katharina T., and Campbell, Diane R.
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- *
ECOLOGICAL disturbances , *GROUND vegetation cover , *NATIVE plants , *SAGE , *VEGETATION monitoring - Abstract
Aims: Post‐fire vegetation recovery is often determined by the similarity of post‐burn with unburned sites because of a lack of in situ information on pre‐fire communities. The inclusion of pre‐fire data can help account for pre‐existing differences and explore recovery also in terms of return to pre‐fire conditions. We used long‐term monitoring data in coastal sage scrub and grasslands to: (a) examine vegetation cover recovery of different functional groups; and (b) determine whether vegetation composition in burned areas has recovered in 4 years after fire with burned to unburned and pre‐ to post‐fire comparisons. Location: Orange County, California, USA. Methods: We analyzed long‐term vegetation monitoring (2007–2021) data from 39 grassland and 58 coastal sage scrub transects in southern California, including observations before and after the 2017 Canyon 2 fire. Linear mixed‐effect models were used to determine whether forb, grass, and shrub covers differed between burned and unburned sites while considering the effects of year and repeated monitoring. We used canonical analysis of principal coordinates to analyze vegetation composition based on burn status and time of sampling. Results: Whereas vegetation cover in grassland recovered quickly, native vegetation cover in burned coastal sage scrub remained lowered 4 years after fire, though forb and non‐native grass cover were higher in some post‐fire years. Community composition in burned coastal sage scrub was still in recovery 4 years after fire when compared with unburned or pre‐fire composition. Although burned and unburned grassland differed after fire in dominant grass species, inclusion of pre‐fire data showed that this was a pre‐existing difference. Conclusions: Coastal sage scrub had not recovered pre‐fire vegetation cover and composition by 4 years after fire, whereas grassland cover rebounded quickly, albeit with shifts in composition over time; patterns that were detected only by having pre‐ and post‐fire data from long‐term monitoring efforts. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
50. Modeling the Potential Habitat Gained by Planting Sagebrush in Burned Landscapes.
- Author
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Heinrichs, Julie A., O'Donnell, Michael S., Orning, Elizabeth K., Pyke, David A., Ricca, Mark A., Coates, Peter S., and Aldridge, Cameron L.
- Subjects
- *
HABITAT selection , *WILDLIFE recovery , *HABITATS , *PLANT habitats , *EXPECTED returns - Abstract
Many revegetation projects are intended to benefit wildlife species. Yet, there are few a priori evaluations that assess the potential efficiency of restoration actions in recovering wildlife habitats. We developed a spatial vegetation–habitat recovery model to gauge the degree to which field planting strategies could be expected to recover multi-factor habitat conditions for wildlife following wildfires. We simulated a wildfire footprint, multiple sagebrush (Artemisia spp.) planting scenarios, and tracked projected vegetation growth for 15 years post-fire. We used a vegetation transition framework to track and estimate the degree to which revegetation could accelerate habitat restoration for a Greater sage-grouse (Centrocercus) population within the Great Basin, western United States. We assessed the amount of habitat 15 years post-fire to estimate the degree to which revegetation could be expected to accelerate habitat restoration. Our results highlight a potential disconnect between the expansive areas required by wide-ranging wildlife such as sage-grouse and the relatively small areas that planting treatments have created. Habitat restorations and planting strategies that are intended to benefit sage-grouse may only speed up localized habitat restoration. This study provides an example of how linked revegetation–habitat modeling approaches can scope the expected return on restoration investment for habitat improvements and support the strategic use of limited restoration resources. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
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