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Post-fire regeneration characterizes woody vegetation of the Cerrado. Several species (e.g., from the Fabaceae) can resprout after fire due to the presence of storage bud-bearing belowground structures, such as xylopodia, having the capacity to rapidly allocate resources for the formation of new aboveground shoots, an advantage in fire-prone ecosystems. Therefore, we evaluated the morphoanatomical structure of the belowground organs, buds and their storage to elucidate fire-related functional traits in relation to regeneration. Besides the strong capacity of plants with xylopodia to resprout and/or their associated root suckers to propagate laterally, they also provide protection against pathogens, through the presence of defence compounds. We evaluated the morphoanatomy and performed histochemical tests with the belowground organs of eight legume species collected in open savannas in Central Brazil. Two species presented a taproot tuber and the six remaining species had a xylopodium as belowground organ. All xylopodia had buds on their upper portion. These organs were basically composed of lignified tissue, containing defence (phenolic compounds and lipidic substances), and storage (starch) substances. All xylopodia were associated to tuberous roots, and in two species these roots were also root suckers. Thus, the presence of belowground storage organs, in combination with stored defence compounds, likely facilitates the persistence of the investigated legumes in fire-prone ecosystems.
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The main concern with concrete at high temperatures is loss of strength and explosive spalling, which are more pronounced in high-strength concretes, such as Ultra-High Performance Concrete (UHPC). The use of polymeric fibers in the mixture helps control chipping, increasing porosity and reducing internal water vapor pressure, but their addition can impact its mechanical properties and workability. This study evaluated the physical and mechanical properties of UHPC with metallic and PVA fibers under high temperatures using a 23 central composite factorial design. The consistency of fresh UHPC and the compressive strength and elasticity modulus of hardened UHPC were measured. Above 300 °C, both compressive strength and elasticity modulus decreased drastically. Although the addition of PVA fibers reduced fluidity, it decreased the loss of compressive strength after exposure to high temperatures. The response surface indicates that the ideal mixture-1.65% steel fiber and 0.50% PVA fiber-achieved the highest compressive strength, both at room temperature and at high temperatures. However, PVA fibers did not protect UHPC against explosive spalling at the levels used in this research.
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Disturbed sleep is a common feature after exposure to a traumatic event, especially when PTSD develops. However, although there is evidence suggesting a potential role of sleep disturbance in the progression of PTSD symptoms, the interrelationship between sleep and PTSD symptoms has yet to be determined. In order to address this knowledge gap, we have investigated the influence of initial sleep characteristics on the evolution of post-traumatic stress disorder (PTSD) symptoms over 4 years of follow-up among individuals exposed to the Brazilian Kiss nightclub fire. Participants were individuals exposed to the 2013 Kiss nightclub fire in Brazil. Sleep characteristics and PTSD symptoms were measured within the 4 years following the fire by self-report questionnaires, such as The Pittsburgh Sleep Quality Index (PSQI), and PTSD Checklist - Civilian version (PCL-C). Generalized estimating equations (GEE) models were used to examine the longitudinal associations (by estimating the relative effects of initial sleep problems on PTSD symptoms after adjusting for covariates). Comprehensive information concerning socio-demographic factors, health status, and sleep complaints were obtained. A total of 232 individuals were included. In GEE models, no significant interactions were observed between sociodemographic variables and PTSD symptoms in the follow-up period, however, associations were found between PTSD at baseline and the following factors: the female gender, the victim individuals and the existence of prior psychiatric disease. Initial subjective sleep parameters were strongly associated with PTSD symptoms over 4 years, mainly the presence of disturbed dreams (p = 0.012), increased sleep latency (p = 0.029), and reduced sleep duration (p = 0.012). Sleep complaints and PTSD symptoms were common among individuals after the disaster. The current study has found that the presence of sleep complaints, especially increased sleep latency, presence of disturbed dreams and short sleep duration, in the initial presentation after the fire was consistently associated with the perpetration of PTSD symptoms in the next 4 years of follow-up. These findings suggest that interventions addressing these sleep complaints have the potential to reduce the persistence and/or severity of PTSD symptoms.
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Trastornos del Sueño-Vigilia , Trastornos por Estrés Postraumático , Humanos , Trastornos por Estrés Postraumático/fisiopatología , Trastornos por Estrés Postraumático/epidemiología , Masculino , Femenino , Adulto , Estudios Longitudinales , Trastornos del Sueño-Vigilia/epidemiología , Trastornos del Sueño-Vigilia/fisiopatología , Trastornos del Sueño-Vigilia/etiología , Persona de Mediana Edad , Brasil/epidemiología , Adulto Joven , Progresión de la Enfermedad , Estudios de SeguimientoRESUMEN
In the face of global climate change, there has been an increase in wildfires around the world, highlighting the need for improved firefighting techniques, such as the use of fire retardants (FRs). These products can enter aquatic systems directly or through runoff, posing potential risks to aquatic biota. In this study, the acute toxicity (24-h/48-h EC50) of three distinct FRs (N-Borate, N-Phosphate+, and N-Phosphate-) was assessed on the immobility of freshwater microcrustaceans Ceriodaphnia dubia and Daphnia magna. The toxicity of the FRs varied up to two orders of magnitude, all of which presented risks to cladocerans even at dilutions much below those recommended by their manufacturers. Among the tested FRs, N-Phosphate- emerged as the most harmful to both species. Specifically, for C. dubia, the 24 h EC50 was 0.005% and the 48 h EC50 was 0.0019%, while for D. magna, 24 h EC50 was 0.003% and the 48 h EC50 was 0.0023%. With the increasing use of FRs for wildfire control, our study highlights the toxicity of newly formulated FRs to daphniid species and emphasizes the need for further evidence-based evaluations of their effects on freshwater ecosystems, which is crucial for choosing FRs that pose the lowest hazard to zooplankton communities.
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The volcano rabbit (Romerolagus diazi) is a lagomorph endemic to the central mountains of the Trans-Mexican Volcanic Belt and is classified as threatened at extinction risk. It is a habitat specialist in bunchgrass communities. The annual wildfires that occur throughout its distribution range are a vulnerability factor for the species. However, the effects of wildfires on volcano rabbit populations are not fully understood. We evaluated the occupancy and change in the volcano rabbit relative abundance index in the burned bunchgrass communities of the Ajusco-Chichinautzin Mountain Range during an annual cycle of wildfire events. Additionally, we assessed the factors that favor and limit occupation and reoccupation by the volcano rabbit using the relative abundance index in burned plots as an indicator of these processes. The explanatory factors for the response of the volcano rabbit were its presence in the nearby unburned bunchgrasses, the height of three species of bunchgrass communities, the proportion of different types of vegetation cover within a 500 m radius around the burned plots, heterogeneity of the vegetation cover, and the extent of the wildfire. Statistical analyses indicated possible reoccupation in less than a year in burned bunchgrass communities adjacent to unburned bunchgrass communities with volcano rabbits. The relative abundance index of volcano rabbits was not favored when the maximum height of the Muhlenbergia macroura bunchgrass community was less than 0.77 m. When the vegetation around the burned plots was dominated by forest (cover >30% of the buffer) and the fire was extensive, the number of latrines decreased per month but increased when the bunchgrass and shrub cover was greater around the burned plots. While the statistical results are not conclusive, our findings indicate a direction for future projects, considering extensive monitoring to obtain a greater number of samples that contribute to consolidating the models presented.
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Ecosistema , Incendios Forestales , Animales , México , Lagomorpha , Conejos , PoaceaeRESUMEN
ABSTRACT Fires are one of the most aggressive and sudden disturbances that can affect ecosystems. During the first months of the year 2022, a series of fires of great magnitude spread in the Iberá streams, which is the largest wetland in Argentina and the second largest in South America after the Pantanal in Brazil, with devastating environmental and social consequences. The aim of this study is to analyze the fires that occurred in the Iberá Reserve and National Park located in the province of Corrientes at the beginning of the year 2022 using remote sensing techniques through the Google Earth Engine processing platform. In this study, the total affected areas were calculated and their severity was analyzed. The results indicate that approximately 20 % of the reserve and close to 50 % of the Iberá National Park have been burned, with a predominance of severity levels ranging from moderate high to high. Remote sensing techniques are a significant resource in fire monitoring, making it a powerful tool in planning regulations or measures aimed at contributing to the mitigation, management, and early warning of fires.
RESUMEN Los incendios son una de las perturbaciones o disturbios más agresivos y repentinos que pueden afectar a los ecosistemas. Durante los primeros meses del año 2022 se propagaron una serie de incendios de gran magnitud en los esteros del Iberá, el cual es el mayor humedal de Argentina y el segundo de Sudamérica luego del Pantanal en Brasil, con consecuencias ambientales y sociales devastadoras. El objetivo del trabajo consiste en analizar los incendios ocurridos en la reserva y el Parque Nacional Iberá ubicada en la provincia de Corrientes a principios del año 2022 aplicando técnicas de teledetección a través de la plataforma de procesamientos de Google Earth Engine. En este trabajo se calculó las áreas totales afectadas analizándose la severidad de estas. Los resultados muestran que se ha quemado alrededor del 20 % de la reserva y cerca del 50 % del Parque Nacional Iberá con predominio de niveles de severidad entre moderada alta y alta. Las técnicas de teledetección son un insumo significativo en el monitoreo de incendios, lo que la vuelve una herramienta potente en la planificación de normativas o medidas que contribuyan con la mitigación, gestión y alerta temprana de incendios.
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This study examines the convergence between traditional and scientific knowledge regarding the use of fire and its potential to trigger wildfires, with possible impacts on ecosystems and human well-being. The research encompasses three distinct natural regions of Ecuador: the coast, the highlands, and the Amazon. Data on traditional fire use were collected through semi-structured interviews with 791 members from five local communities. These data were compared with climatic variables (rainfall (mm), relative humidity (%), wind speed (km/h), and wind direction) to understand the climatic conditions conducive to wildfires and their relationship with human perceptions. Furthermore, the severity of fires over the past 4 years (2019-2022) was assessed using remote sensing methods, employing the Normalized Burn Ratio (NBR) and the difference between pre-fire and post-fire conditions (NBR Pre-fire-NBR Post-fire). The results revealed a significant alignment between traditional knowledge, climatic data, and many fires, which were of low severity, suggesting potential benefits for ecosystems. These findings not only enable the identification of optimal techniques and timing for traditional burns but also contribute to human well-being by maintaining a harmonious balance between communities and their environment. Additionally, they provide valuable insights for the development of more inclusive and effective integrated fire management strategies in these natural areas of Ecuador.
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Conocimiento , Incendios Forestales , Ecuador , Humanos , Masculino , Incendios , Femenino , Adulto , Ecosistema , Persona de Mediana Edad , AncianoRESUMEN
In fire-prone ecosystems, plant traits are influenced by the fire regime, thus reproduction and establishment can be altered by this disturbance. Changes in fire frequency and history can therefore influence seed and germination traits. We investigated the effects of short-term fire exclusion on seed and germination traits of species from tropical open savannas. Seeds from 27 species were collected from two areas with distinct fire histories: recently and frequently burned (RB) or unburned for 5 to 7 years (E). Seeds from both areas underwent germination trials under optimal conditions for 30 days. Also, 10 species were exposed to high temperature treatments (100 or 200 °C) and seed and germination traits measured. Comparisons were then made for each trait, analysing each species separately, between the two areas. Approximately 85% of species studied had at least one of their germination traits altered in the RB area compared to the E area. Clear differences included lower viability and faster germination in seeds from RB areas. Seed traits of 70% of measured species differed between the two areas. Our results show species-specific trait response to different fire histories. For example, faster germination and lower viability of seeds from RB plots suggest selection for faster maturing individuals and differences in resourcing, respectively, under a regime of frequent fire. This study provides insights into fire effects on regeneration responses of tropical savanna species and also points to the need for more studies evaluating the effects of fire history on seed traits.
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Forest plantations are economically and environmentally relevant, as they play a key role in timber production and carbon capture. It is expected that the future climate change scenario affects forest growth and modify the rotation age for timber production. However, mathematical models on the effect of climate change on the rotation age for timber production remain still limited. We aim to determine the optimal rotation age that maximizes the net economic benefit of timber volume in a negative scenario from the climatic point of view. For this purpose, a bioeconomic optimal control problem was formulated from a system of Ordinary Differential Equations (ODEs) governed by the state variables live biomass volume, intrinsic growth rate, and area affected by fire. Then, four control variables were associated to the system, representing forest management activities, which are felling, thinning, reforestation, and fire prevention. The existence of optimal control solutions was demonstrated, and the solutions of the optimal control problem were also characterized using Pontryagin's Maximum Principle. The solutions of the model were approximated numerically by the Forward-Backward Sweep method. To validate the model, two scenarios were considered: a realistic scenario that represents current forestry activities for the exotic species Pinus radiata D. Don, and a pessimistic scenario, which considers environmental conditions conducive to a higher occurrence of forest fires. The optimal solution that maximizes the net benefit of timber volume consists of a strategy that considers all four control variables simultaneously. For felling and thinning, regardless of the scenario considered, the optimal strategy is to spend on both activities depending on the amount of biomass in the field. Similarly, for reforestation, the optimal strategy is to spend as the forest is harvested. In the case of fire prevention, in the realistic scenario, the optimal strategy consists of reducing the expenses in fire prevention because the incidence of fires is lower, whereas in the pessimistic scenario, the opposite is true. It is concluded that the optimal rotation age that maximizes the net economic benefit of timber volume in P. radiata plantations is 24 and 19 years for the realistic and pessimistic scenarios, respectively. This corroborates that the presence of fires influences the determination of the optimal rotation age, and as a consequence, the net economic benefit.
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Incendios , Bosques , Incendios/prevención & control , Conceptos Matemáticos , Modelos BiológicosRESUMEN
The recycling of fly ash from municipal solid waste incineration is currently a global issue. This work intends to examine the viability of a novel recycling alternative for fly ashes as a component of fire-resistant plates. To lessen the quantity of heavy metal leaching, the fly ash was utilized after being washed using a water/fly ash ratio of 2 for one hour. Subsequently, an inexpensive, straightforward molding and curing process was used to create a plate, with a composition of 60%wt of MSWI-FA, 30%wt of gypsum, 0.5%wt of glass fiber and 9.5%wt of vermiculite. The plate exhibited high fire resistance. Furthermore, it demonstrated compression, flexural strength and surface hardness slightly lower than the requirements of European Standards. This allows for manufacturing plates with a high washed MSWI-FA content as fire protection in firewalls and doors for homes and commercial buildings. A Life Cycle Assessment was carried out. The case study shows that a 60% substitution of gypsum resulted in an environmental impact reduction of 8-48% for all impact categories examined, except four categories impacts (marine eutrophication, human toxicity (cancer), human non-carcinogenic toxicity and water depletion, where it increased between 2 and 718 times), due to the previous washing of MSWI-FA. When these fly ashes are used as a raw material in fire-resistant materials, they may be recycled and offer environmental advantages over more conventional materials like gypsum.
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Steel cross-sections with thin walls are vulnerable to fire-induced buckling instability, which reduces their load-bearing capacity. Eurocode 3 design provisions have been found inadequate, leading to alternative methods such as effective design strategies and advanced structural models built mostly with shell FE, which can be complex. For Class 4 steel beam-columns subjected to fire conditions, beam-type modelling to predict the Flexural-Torsional Buckling (FTB) strength has been proposed as an alternative approach, but it has not yielded satisfactory results for large compressive load eccentricities. This paper presents two new low computational cost modelling strategies based on Timoshenko's beam FE to address this issue: the Single beam-column Model (SbcM) and the Cruciform beam-column Model (CbcM). The first consists of a single line of beam FE, while the second uses a grid of beam FE for more flexibility. Both strategies effectively simulate the FTB behaviour in Class 4 steel beam-column during a fire, offering quicker computations compared to shell models. Still, the single-line model is favoured for its simplicity, making it more efficient in analysing complex fire engineering problems.
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BACKGROUND AND AIMS: Fire may favour plant flowering by opening the vegetation and increasing abiotic resource availability. Increased floral display size can attract more pollinators and increase the absolute fruit and seed production immediately after the fire. However, anthropogenic increases in fire frequency may alter these responses. We aim to assess the effects of fire on pollination and reproductive success of plants at the global scale. METHODS: We performed a systematic literature review and meta-analyses to examine overall fire effects as well as different fire parameters on pollination and on plant reproduction. We also explored to what extent the responses vary among pollinators, pollination vectors, plant regeneration strategies, compatibility systems, vegetation types and biomes. KEY RESULTS: Most studies were conducted in fire-prone ecosystems. Overall, single fires increased pollination and plant reproduction but this effect was overridden by recurrent fires. Floral visitation rates of pollinators were enhanced immediately following a wildfire, and especially in bee-pollinated plants. Fire increased the absolute production of fruits or seeds but not the fruit or seed set. The reproductive benefits were mostly observed in wind-pollinated (graminoids), herbaceous and resprouter species. Finally, fire effects on pollination were positively correlated with fire effects on plant reproductive success. CONCLUSIONS: Fire has a central role in pollination and plant sexual reproduction in fire-prone ecosystems. The increase in the absolute production of fruits and seeds suggests that fire benefits on plant reproduction are likely driven by increased abiotic resources and the consequent floral display size. However, reproduction efficiency, as measured by fruit or seed set, does not increase with fire. In contrast, when assessed on the same plant simultaneously, fire effects on pollination are translated into reproduction. Increased fire frequency due to anthropogenic changes can alter the nature of the response to fire.
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This study aimed to identify the most important, frequently performed, and physically demanding tasks performed by Brazilian firefighters and to identify tasks that could be used to assess physical fitness. A subjective task analysis was conducted. Five hundred twenty-four firefighters (84% male; 16% females) responded to an online survey and rated 37 tasks across three domains (most important, most frequent, and most physically demanding). A dichotomous decision analysis was used to inform the proposed physical fitness tests. Wildland firefighting tasks presented the highest overall mean rate. Traffic control was considered the most important and frequently performed task. Lifeguard rescue was considered the most physically demanding task. The dichotomous analysis identified 14 essential tasks (seven structural firefighting and seven automobile accidents). The tasks identified may be helpful in developing criterion physical fitness tests and training programs related to firefighters' demands.Practitioner summary: The unpredictability, variability, and dangerousness of firefighting make it challenging to observe the physical demands imposed on firefighters. A subjective task analysis was conducted to identify essential tasks performed by Brazilian firefighters. Wildland firefighting, lifeguard rescue, automobile accidents, and structural firefighting tasks were the most important, frequent, and physically demanding.
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Bomberos , Femenino , Humanos , Masculino , Brasil , Análisis y Desempeño de Tareas , Aptitud Física , Ejercicio FísicoRESUMEN
Neotropical xerophytic forest ecosystems evolved with fires that shaped their resilience to disturbance events. However, it is unknown whether forest resilience to fires persists under a new fire regime influenced by anthropogenic disturbance and climate change. We asked whether there was evidence for a fire severity threshold causing an abrupt transition from a forest to an alternative shrub thicket state in the presence of typical postfire management. We studied a heterogeneous wildfire event to assess medium-term effects (11 years) of varying fire severity in a xerophytic Caldén forest in central Argentina. We conducted vegetation surveys in patches that were exposed to low (LFS), medium (MFS), and high (HFS) fire severities but had similar prefire woody canopy cover. Satellite images were used to quantify fire severity using a delta Normalized Burning Ratio (dNBR) and to map prefire canopy cover. Postfire total woody canopy cover was higher in low and medium than high severity patches, but the understory woody component was highest in HFS patches. The density of woody plants was over three times higher under HFS than MFS and LFS due to the contribution of small woody plants to the total density. Unlike LFS and MFS patches, the small plants in HFS patches were persistent, multistem shrubs that resulted from the resprouting of top-killed Prosopis caldenia trees and, more importantly, from young shrubs that probably established after the wildfire. Our results suggest that the Caldén forest is resilient to fires of low to moderate severities but not to high-severity fires. Fire severities with dNBR values > ~600 triggered an abrupt transition to a shrub thicket state. Postfire grazing and controlled-fire treatments likely contributed to shrub dominance after high-severity wildfire. Forest to shrub thicket transitions enable recurring high-severity fire events. We propose that repeated fires combined with grazing can trap the system in a shrub thicket state. Further studies are needed to determine whether the relationships between fire and vegetation structure examined in this case study represent general mechanisms of irreversible state changes across the Caldenal forest region and whether analogous threshold relationships exist in other fire-prone woodland ecosystems.
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Ecosistema , Incendios Forestales , Bosques , Madera , ÁrbolesRESUMEN
Microsporidia are natural pathogens of arthropods and have been used as biological control against insect pests. In the United States, efforts to control the invasive Red Imported Fire Ant, Solenopsis invicta, and Black Imported Fire Ant, Solenopsis richteri, have included the use of the microsporidium, Kneallhazia solenopsae. However, there is limited information about the genetic differences among the microsporidian variants found in S. invicta and in S. richteri. In this study, we assessed the prevalence and genetic diversity of K. solenopsae in native populations of S. richteri in Argentina (South America). Additionally, we examined the social parasitic ant, Solenopsis daguerrei, which is found in some S. richteri nests, for the presence of this microsporidium. The survey of 219 S. richteri nests revealed K. solenopsae infections in all five sites analyzed, with 28 colonies (12.8%) positive for the microsporidium. Among the 180 S. daguerrei individuals collected, seven ants (3.9%) from three sites tested positive for K. solenopsae. Phylogenetic analyses of the microsporidian variants present in S. richteri and S. daguerrei based on partial small subunit ribosomal gene sequences (SSU rRNA) showed that both ant species shared the same variant, which is different from the ones found in S. invicta. Further studies are needed to determine the pathogenicity of genetically different K. solenopsae variants among Solenopsis species.
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There is only a very short reaction time for people to find the best way out of a building in a fire outbreak. Software applications can be used to assist the rapid evacuation of people from the building; however, this is an arduous task, which requires an understanding of advanced technologies. Since well-known pathway algorithms (such as, Dijkstra, Bellman-Ford, and A*) can lead to serious performance problems, when it comes to multi-objective problems, we decided to make use of deep reinforcement learning techniques. A wide range of strategies including a random initialization of replay buffer and transfer learning were assessed in three projects involving schools of different sizes. The results showed the proposal was viable and that in most cases the performance of transfer learning was superior, enabling the learning agent to be trained in times shorter than 1 min, with 100% accuracy in the routes. In addition, the study raised challenges that had to be faced in the future.
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Aprendizaje , Refuerzo en Psicología , Humanos , Algoritmos , Programas Informáticos , Instituciones AcadémicasRESUMEN
Anthropogenic fires are an increasing threat to tropical savannas and their plant populations. In the Brazilian Cerrado, human-made fires at the end of the dry season are replacing natural fires at the beginning of the dry season. Critically, these late burns occur under more intense climate variables. Here, we aimed to understand the potential role of fire seasonality on individuals of Anacardium humile, a widespread Cerrado species of cultural and economic importance. We conducted two prescribed burnings, one at the beginning of the dry season (early burning) and one at the end of the dry season (late burning) when climate variables were remarkably different. We assessed the reproductive responses of A. humile individuals over 4 years and compared individuals from the fire treatments with those from an unburned area (control). The reproductive phenology of A. humile varied over time and was influenced by climate variables. The seasons of different burning had similar impacts on the reproductive phenology of A. humile, and this impact lasted for at least 4 years. While A. humile populations do not depend on fire for reproduction, they produced more flowers and fruits for up to 2 years with the fire treatments. We provide empirical evidence of the role of climate variables on the phenology of A. humile and demonstrate the importance of considering the role of time after fire events. The similar responses of A. humile to fire seasonality show that Cerrado fire management can be more complex than previously thought.
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Anacardium , Ecosistema , Humanos , Pradera , Plantas , ReproducciónRESUMEN
Forest fires in North America are becoming larger in area and burning with higher severity as a result of climate change and land management practices. High-severity, stand-replacement fires can inflict major changes to forest insect communities, potentially extirpating many species through altered post-fire habitat resources. We assessed forest-dwelling macrolepidopteran moth communities in mixed conifer and ponderosa pine forests during the first year after the 2011 Las Conchas fire in New Mexico, USA. We deployed blacklight traps in replicated burned and unburned stands during June, July, and August in 2012. We collected 9,478 individuals, representing 211 species and 8 families. Noctuidae (124 species) and Geometridae (53) comprised the majority of the taxa, followed by Erebidae (21), Sphingidae (5), Notodontidae (3), Lasiocampidae (2), Saturniidae (2), and Drepanidae (1). Moth communities (species composition and abundances) in each forest type (mixed conifer vs. ponderosa pine) were statistically distinguishable, but shared 56.4% (119) of observed species. Overall, compared to unburned forests, post-fire moth communities in both forest types had significantly lower numbers of individuals, species richness and diversity, and lower evenness in ponderosa pine forests. As expected, categorizing moth taxa by larval host plant taxa revealed that reductions of moth populations following fire were associated with the elimination or reduction of available larval host plants (particularly conifers, oaks, and junipers). We predict that future moth community succession will likely parallel the overall transformation from a forested landscape to a montane meadow/grassland ecosystem, with continued reduction in tree-feeding species and increasing dominance by forb/grass-feeding species.
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Incendios , Mariposas Nocturnas , Tracheophyta , Incendios Forestales , Animales , Ecosistema , New Mexico , BosquesRESUMEN
Different ecosystems evolved and are maintained by fire, with their vegetation hosting species with a wide diversity of persistence strategies allowing them to insulate their body and resprout new branches after fire disturbance. Changes in fire regime are predicted due to climate change, either by promoting more frequent and/or severe fires or by reducing the number of fire events due to the limitation of fuel load. Predicting the future of fire-driven ecosystems is a complex task as species' survival depends on many factors that vary in space and time. Since plants are constantly experiencing new environments as they grow through meristem development, woody plant modularity, modules morpho-physiological aspects and their integration should be considered when investigating species strategies in fire-prone ecosystems: according to their position and their tissue composition, plants' modules experience fire differently and will contribute differently to other modules and the whole plant survival, with consequences cascading over the overall vegetation structure. Growth modules may hold the key to understanding how fast plants can get protected from fire, ultimately helping us to predict which species will persist across changing fire regimes. We present an empirical example showing how different fire-return intervals translate into distinct pressures on the timing, protection and location of modules, and discuss how these can translate into modifications in the vegetation structure due to climate change.
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Indolent systemic mastocytosis is a rare disease characterized by an increased number of mast cells in the bone marrow and other tissues, such as the liver, spleen, lymph nodes, and skin. Patients with indolent systemic mastocytosis and high serum tryptase levels are at risk for Hymenoptera venom-induced anaphylaxis. Hymenoptera venom immunotherapy in patients with specific IgE is safe and effective. While some patients can receive ultra-rush venom immunotherapy with minimal side effects, omalizumab effectively protects against anaphylaxis during the build-up phase.
A mastocitose sistêmica indolente é uma doença rara caracterizada por um número aumentado de mastócitos na medula óssea e em outros tecidos, como fígado, baço, linfonodos e pele. Pacientes com mastocitose sistêmica indolente e altos níveis séricos de triptase correm risco de anafilaxia induzida pelo veneno dos Hymenoptera. A imunoterapia com veneno de himenópteros em pacientes com IgE específica é segura e eficaz. Embora alguns pacientes possam receber imunoterapia com veneno ultrarrápido com efeitos colaterais mínimos, o omalizumabe protegeu efetivamente contra a anafilaxia durante a fase de acúmulo.