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The role of holm oak edges in the control of disturbance and conservation of plant diversity in fire-prone landscapes

Azevedo, João; Possacos, Anabela; Aguiar, Carlos; Amado, Anabela; Miguel, Luis; Dias, Rui; Loureiro, Carlos; Fernandes, Paulo M.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
37.04%
Holm oak (Quercus rotundifolia) woodlands have been able to persist in fire-prone landscapes in northern Portugal where they seem to play a relevant role in community and landscape level patterns and processes, namely in the control of disturbance events and in the maintenance of biodiversity. In this research we tested the following hypotheses: (i) holm oak woodlands affect fire behavior, mainly by disrupting and delaying fire spread; (ii) disruption and delaying of fire spread is due to fire extinction at the edge of woodlands; and (iii) plant diversity is favored by frequent low-intensity fires as a result of the control of fire spread by holm oak woodland edges. We sampled herbaceous, shrub and tree structure and herbaceous plant composition across edges of holm oak woodlands with known recent contact with fire. Using BehavePlus we converted structural data into fuel models and simulated fire behavior for the locations sampled along the exterior–interior gradient of the woodlands. Our results indicate that holm oak woodlands play a relevant role in the control of fire spread and in the maintenance of plant diversity. We found differences in simulated maximum rate of fire spread (ROS) and fireline intensity (FLI) between outside and inside woodlands as well as a 100% probability of fire extinction when fuel moisture was >12% and wind speed at 10 m aboveground was <40 km h 1...

FIRE INTENSITY AND SEVERITY IN BRAZILIAN CAMPOS GRASSLANDS

FIDELIS, Alessandra; DELGADO-CARTAY, Maria Dolores; BLANCO, Carolina C.; MUELLER, Sandra C.; PILLAR, Valerio D.; PFADENHAUER, Joerg
Fonte: INTERCIENCIA Publicador: INTERCIENCIA
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
37.04%
Brazilian Campos grasslands are rich in species and the maintenance of its diversity and physiognomy is dependent on disturbance (e.g. fire and grazing) Nevertheless, studies about fire intensity and severity are inexistent. The present paper describes fire parameters, using 14 experimental burn plots in southern Brazil (30 degrees 02` to 30 degrees 04`S, and 51 degrees 06` to 51 degrees 09`W. 311masl). Two sites under different fire histories were chosen: frequently burned and excluded since six years. Experimental burning was performed during summer (2006-2007), when most burning takes place in these grasslands. The following parameters were measured: air temperature and moisture, vegetation height, wind speed, fuel (fine, coarse), fuel moisture, fire temperatures (soil level and at 50cm), ash, residuals, flame freight, fire duration: burning efficiency and fire intensity were later calculated. Fuel load varied from 0.39 to 1.44kg.m(-2). and correlated positively with both fire temperature and fire intensity. Fire temperatures ranged 47 to 537.5 degrees C. being higher in the excluded site Fire intensity was low compared to grassland elsewhere (36 5-319.5kW.m(-1)), differing significantly between sties Fine fuel was the variable that best explained fire intensity. The results on fire intensity and severity in Campos grasslands can be considered a pilot study...

Aspectos de análise de risco das estruturas de concreto em situação de incêndio.; Aspects of risk analysis of concrete structures in fire situation.

Cuoghi, Ricardo de Scarabello
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 30/08/2006 PT
Relevância na Pesquisa
37.02%
O risco de incêndio e seus prejuízos às vidas humanas e ao patrimônio tornaram-se cada vez maiores com o desenvolvimento urbano e a evolução da construção civil. Assim, os meios de proteção contra o incêndio tornam-se cada vez mais necessários, tanto os meios ativos (sprinklers, brigada de incêndio, etc), quanto os meios passivos (proteção térmica de estruturas, etc). Em situação de incêndio, a proteção à vida e ao patrimônio deve ser garantida pelos meios de proteção das edificações evitando-se o colapso de parte ou toda estrutura. A eventualidade do sinistro não deve ser desprezada sendo que, melhorar o desempenho das estruturas visando a iminência de um incêndio é sinônimo de economia em um aspecto abrangente: proteção à vida, ao patrimônio e à atividade econômica desenvolvida no estabelecimento. Neste trabalho, realiza-se uma apresentação do tema comportamento das estruturas de concreto em situação de incêndio, abordando aspectos de análise de risco incêndio, seguro contra incêndio, o fenômeno incêndio e suas variáveis, meios de proteção térmica das estruturas e aspectos arquitetônicos e estruturais que influenciam na probabilidade de ocorrência de um incêndio. No plano experimental...

Análise da eficiência dos sistemas de compartimentação vertical externa por afastamento entre janelas e por projeções horizontais segundo as exigências normativas brasileiras; Analysis of the efficiency of the external vertical compartmentation systems for separation between windows and external horizontal projections according to brazilian’s fire safety codes

Rodrigues, Eduardo Estevam Camargo
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
37.04%
Os códigos brasileiros de segurança contra incêndio e pânico (SCIP) possuem inúmeras divergências no que tange aos detalhamentos exigidos para a instalação de diversos sistemas de prevenção e proteção. Dentre eles, existe o sistema estrutural de compartimentação vertical externa, o qual prescreve afastamento vertical entre janelas ou construção de projeções horizontais externas entre as aberturas, para limitação da propagação do fogo aos pavimentos acima consecutivos. Comprovadamente, as normas referenciam a necessidade de resistência ao fogo dos materiais constituintes do sistema, no entanto, não indicam a eficiência ao objetivo proposto, confinar o fogo em seu compartimento de origem ou retardar sua propagação. O objetivo deste trabalho é analisar, sob a ótica da dinâmica de propagação do incêndio, a eficiência do sistema de compartimentação vertical externa por afastamento entre as janelas e por implantação de projeções horizontais como continuidade dos pisos, segundo os detalhamentos exigidos nas normas brasileiras. Para tanto, foram realizados ensaios de campo em escala reduzida (1/3), com diferentes configurações de fachadas e cargas de incêndio, sem vento, utilizando-se termopares, termografia e fotografia. Também...

Fire intensity and severity in brazilian campos grasslands

Fidelis, Alessandra Tomaselli; Delgado Cartay, Maria Dolores; Blanco, Carolina Casagrande; Muller, Sandra Cristina; Pillar, Valerio de Patta; Pfadenhauer, Jorg Sepp
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
ENG
Relevância na Pesquisa
37.04%
Brazilian Campos grasslands are rich in species and the maintenance of its diversity and physiognomy is dependent on disturbance (e.g. fire and grazing). Nevertheless, studies about fire intensity and severity are inexistent. The present paper describes fire parameters, using 14 experimental burn plots in southern Brazil (30º02’ to 30º04’S, and 51º06’ to 51º09’W, 311masl). Two sites under different fire histories were chosen: frequently burned and excluded since six years. Experimental burning was performed during summer (2006-2007), when most burning takes place in these grasslands. The following parameters were measured: air temperature and moisture, vegetation height, wind speed, fuel (fine, coarse), fuel moisture, fire temperatures (soil level and at 50cm), ash, residuals, flame height, fire duration; burning efficiency and fire intensity were later calculated. Fuel load varied from 0.39 to 1.44kg·m-2, and correlated positively with both fire temperature and fire intensity. Fire temperatures ranged 47 to 537.5°C, being higher in the excluded site. Fire intensity was low compared to grassland elsewhere (36.5- 319.5kW·m-1), differing significantly between sites. Fine fuel was the variable that best explained fire intensity. The results on fire intensity and severity in Campos grasslands can be considered a pilot study...

Fire-smart management of forest landscapes in the Mediterranean basin under global change

Fernandes, Paulo
Fonte: Universidade de Trás-os-Montes e Alto Douro Publicador: Universidade de Trás-os-Montes e Alto Douro
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
37.04%
Modified, more severe fire regimes are developing in the Mediterranean basin as a result of changes in land use and climate. Current fire management privileges fire suppression and tends to ignore land management issues, which may further accelerate the transition to a more fire-prone future and magnify the problem. Fire-smart management aims to control the fire regime by intervening on vegetation (fuel) to foster more fire-resistant (less flammable) and/or fire-resilient environments. Scientific knowledge supporting the creation and maintenance of fire-smart wildlands is critically reviewed, considering the landscape and the forest stand scales. Fuel management strategies (isolation, structural modification, type conversion) are discussed in regards to their current and future potential to buffer the effects of global change on the extent and severity of fires. Uncertainty in the outcomes of fire-smart management arises mainly from insufficient understanding of the relative weights of fuel and weather-drought on the fire regime. Likewise, linkage between global change processes and the fire regime is not straightforward. Shrublands and, in general, open and dry vegetation types will prevail even more in future landscapes. Decrease in biomass will limit fire incidence over parts of the Mediterranean. However...

Efeitos de diferentes regimes de fogo na comunidade de formigas do cerrado; Effects of different fire regimes in the Cerrado ant community

Maravalhas, Jonas
Fonte: Universidade Federal de Uberlândia Publicador: Universidade Federal de Uberlândia
Tipo: Dissertação
POR
Relevância na Pesquisa
37.05%
Distúrbios têm recebido crescente reconhecimento como importantes fatores estruturantes da natureza. O fogo é importante em ambientes xéricos e sazonais, mantendo a estrutura do habitat e as populações locais. O Cerrado é uma savana Neotropical sujeita a queimadas freqüentes, porém mudanças no regime de fogo ameaçam a conservação deste bioma. A exclusão do fogo beneficia árvores e eventualmente transforma a vegetação numa floresta. Por outro lado, a intensificação das queimadas beneficia gramíneas e pode ser danoso a espécies adaptadas a regimes mais brandos. Portanto é fundamental desenvolver estratégias apropriadas de manejo do fogo, porém a falta de informação sobre os efeitos do fogo são um empecilho. Formigas são importantes em ambientes tropicais e respondem a mudanças no habitat, ideais para o estudo de impactos ambientais. Nós registramos mudanças na comunidade de formigas entre áreas de Cerrado submetidas a diferentes regimes de fogo. Os efeitos da freqüência de queimadas foram testados entre parcelas protegidas do fogo (C0) e parcelas queimadas no meio da estação seca a cada quatro (M4) ou dois (M2) anos. Este último foi também comparado com parcelas bianuais queimadas no início (E2) ou fim da estação seca (L2)...

Multi-physics modelling for the safety assessment of complex structural systems under fire

GENTILI, FILIPPO
Fonte: La Sapienza Universidade de Roma Publicador: La Sapienza Universidade de Roma
Tipo: Tese de Doutorado
EN
Relevância na Pesquisa
37.07%
Among all structures, high-rise buildings pose specific design challenges with respect of fire safety for a number of reasons, in particular the evaluation of both the fire development (fire action) and response of the structural system to fire (structural behaviour). In relation to the fire action, large compartments and open hallways often present in modern high-rise buildings don’t let themselves to be designed within compliance to current codes and standards. A comprehensive analysis of the fire environment is required to understand the fire dynamics in these cases. A Computational Fluid Dynamic (CFD) model allows a quite accurate representation of realistic fire scenarios, because it takes into account the distribution of fuel, the geometry, the occupancy of individual compartments and the temperature rise in structural elements that are located outside the tributary area of fire scenario. In relation to the structural behaviour under fire, the passive fire resistance of structural elements and the intrinsic robustness of the system are the only measures to rely on in order to maintain the structural integrity of the building during and after the fire and avoid major economic losses due to structural failures and prolonged inoperability of the premises. Disproportionate damages induced by fire can be avoided with a proper design of the structure...

Fire and grazing in a mesic tallgrass prairie: impacts on plant species and functional traits

Spasojevic, Marko J.; Aicher, Rebecca J.; Koch, Gregory R.; Marquardt, Emily S.; Mirotchnick, Nicholas; Troxler, Tiffany G.; Collins, Scott
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica Formato: application/pdf
Relevância na Pesquisa
37.02%
Fire is a globally distributed disturbance that impacts terrestrial ecosystems and has been proposed to be a global “herbivore.” Fire, like herbivory, is a top-down driver that converts organic materials into inorganic products, alters community structure, and acts as an evolutionary agent. Though grazing and fire may have some comparable effects in grasslands, they do not have similar impacts on species composition and community structure. However, the concept of fire as a global herbivore implies that fire and herbivory may have similar effects on plant functional traits. Using 22 years of data from a mesic, native tallgrass prairie with a long evolutionary history of fire and grazing, we tested if trait composition between grazed and burned grassland communities would converge, and if the degree of convergence depended on fire frequency. Additionally, we tested if eliminating fire from frequently burned grasslands would result in a state similar to unburned grasslands, and if adding fire into a previously unburned grassland would cause composition to become more similar to that of frequently burned grasslands. We found that grazing and burning once every four years showed the most convergence in traits, suggesting that these communities operate under similar deterministic assembly rules and that fire and herbivory are similar disturbances to grasslands at the trait-group level of organization. Three years after reversal of the fire treatment we found that fire reversal had different effects depending on treatment. The formerly unburned community that was then burned annually became more similar to the annually burned community in trait composition suggesting that function may be rapidly restored if fire is reintroduced. Conversely...

The Kangaroo Island bushfires of 2007: a meteorological case study and WRF-fire simulation

Peace, M.; Mattner, T.; Mills, G.
Fonte: The Modelling and Simulation Society of Australia and NZ; online Publicador: The Modelling and Simulation Society of Australia and NZ; online
Tipo: Conference paper
Publicado em //2011 EN
Relevância na Pesquisa
37.04%
In December 2007, Kangaroo Island was set ablaze by numerous dry lightning strikes. Our research into the event has been conducted in two parts; a case study investigating the interactions between the local meteorology and observed fire behaviour, followed by simulations using the coupled atmospheric fire behaviour model WRF-fire. The findings from the case study highlight the importance of including information on atmospheric instability and spatial variation in meteorological parameters in fire weather forecasts. Our preliminary simulations using WRF-fire have explored the ability of the model to capture phenomena observed in the case study. The case study identified two occurrences of unusual fire behaviour which have been simulated: the first, when a fire located in a local sea breeze front convergence zone produced a spectacular convection column which developed by release of potential atmospheric instability triggered by local lifting; the second, when unprecedented fire behaviour was observed in relatively benign conditions, hypothesised to be due to convective plume entrainment of dry air aloft, enhanced by topographically driven processes and very dry, open structured fuels. The circumstances leading to the unusual fire behaviour(s) illustrate known limitations in the current Australian approach to fire weather forecasting...

Fire in arid and semi-arid Australia: 1998-2004.

Turner, Dorothy
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2009
Relevância na Pesquisa
37.01%
Fire is a crucial element in shaping our world, whether caused naturally by lightning or by humans, either accidentally or on purpose. These fires can have both positive and negative consequences and impacts on our natural environment, human health, society and its economics, and global climate through carbon emissions. In arid and semi-arid Australia (70% of the continent), individual fires frequently exceed 1 million hectares, and have collectively burnt up to 9% of this total area in a single year. Stakeholders all have different outlooks and priorities about these phenomena. Little objective information about the fire regime and its drivers has been available for this vast area with its very low population density, with previous analyses limited in spatial and/or temporal extent. This lack of knowledge has hampered attempts at effective management. Satellite imagery enables active fires to be detected as fire hotspots, and burnt areas to be mapped as patches from the change of surface reflectance properties in successive images. The National Oceanographic and Atmospheric Administration’s (NOAA) Advanced Very High Resolution Radiometer (AVHRR) imagery has recently been used to map both fire hotspots (FHS) and fire affected areas (FAA) for the entire Australian continent dating back to 1998. In this dissertation...

Managing post-fire soil erosion in the southern Mount Lofty Ranges.

Morris, Rowena Helen
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2013
Relevância na Pesquisa
37.04%
Post-fire soil erosion is a great concern to land managers due to the potential adverse effects on water quality, the alteration to soil profiles and the detrimental impacts on human communities. To reduce the potential adverse effects of post-fire erosion mitigation actions have been instigated following severe wildfires. Various programs of prescribed burning have been initiated to reduce the risk of wildfires. In order to predict and manage post-fire erosion a clear understanding is needed of the influential environmental variables, associated processes and whether mitigation actions will be effective. In the Southern Mount Lofty Ranges there is a paucity of post-fire erosion data from which to generate evidence-based predictive models and management recommendations. This thesis has the overarching goal of developing evidence-based options for managing post-fire sediment movement in the Southern Mount Lofty Ranges. Evidence-based management of sediment movement from both prescribed fire and wildfire can reduce potential erosion and hence protect regional natural services such as soil profile formation, soil mineral health, the regulation of water quality and maintenance of local landscape character. A case study of the Southern Mount Lofty Ranges is used to produce evidence-based options for managing post-fire erosion in relation to a wildfire at Mount Bold and ten prescribed burns conducted within the Southern Mount Lofty Ranges. Field techniques included visual erosion assessments...

Coupled fire-atmosphere simulations of three Australian fires where unusual fire behaviour occurred.

Peace, Marika
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2014
Relevância na Pesquisa
37.06%
Predicting where and how a fire will burn is critical information for mitigating the impacts of bushfires and minimising risk at fuel reduction burns. Firefighter entrapments and fatalities occur mostly at fires that display rapid changes or fluctuations in fire activity. In this thesis, I explore several of the factors that lead to rapid changes in fire behaviour. Understanding these factors is necessary in order to produce accurate fire predictions, which are critical for fire-fighter safety and effective operations. Weather is a primary driver of fire activity; consequently, meteorological information is a key input for anticipating fire behaviour. At present, weather forecasts focus on near-surface conditions; but fires and the atmosphere are three dimensional, and dynamical interactions occur that can have a dramatic influence on fire behaviour. However, these fire-atmosphere interactions are poorly understood due to their complex nature and the difficulty of collecting observational data from a bushfire. In order to further understanding of dynamical interactions between a fire and the surrounding atmosphere, we have simulated three Australian fires where unexpected fire activity occurred, using the coupled fire-atmosphere model WRF and SFIRE. The coupled simulations have been run in feedback on and feedback off mode in order to assess the impact that the fires have on their surrounding atmosphere. The results show significant changes to the mesoscale atmospheric structure as result of the energy released by the fire. Computational fire behaviour models are being used by fire managers in real time and this use will grow in the future. The question is...

Policy options analysis and the National Fire Operations Reporting System

McAdams, Michael A.
Fonte: Monterey, California: Naval Postgraduate School Publicador: Monterey, California: Naval Postgraduate School
Tipo: Tese de Doutorado
Relevância na Pesquisa
37.01%
Approved for public release; distribution is unlimited; Effectively managing a fire department requires leaders to understand that allocation adjustment to resources will impact the outcome of structure fire incidents. It is important that fire service leaders and politicians understand how resources deployed impact firefighter and civilian injuries, death, and property loss. Additionally, fire service leaders must have reliable data to understand the complexities and apply the correct resources. The National Fire Incident Reporting System (NFIRS) is a voluntary system and only describes the cause of a fire, its origin, and how a fire spreads within a structure. Information submitted into the NFIRS database does not provide real-time information. Despite recent advances in technology, fire departments do not have a method to determine the availability of resources able and ready to respond or the capability of those resources to manage the event. This thesis will identify those specific definitions and describe the operational effectiveness of fire department resources deployed to a structure fire incident. Operational effectiveness states the match between the resources deployed to the incident type and management of the events. Explaining these terms empowers the leader to allocate the correct resources—reducing firefighter and civilian injury...

Regrowth and recruitment of the rare shrub Logania saxatilis in response to fire.

Grehn, Ute Susanne
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2015
Relevância na Pesquisa
37%
This project investigated regrowth and recruitment response of the rare shrub Logania saxatilis (Rock Logania) after exposure to fire. Field monitoring took place in two reserves in the Southern Flinders Ranges, South Australia: Mount Remarkable National Park (Mount Remarkable) and Telowie Gorge Conservation Park (Telowie). The two sites differed in several aspects including vegetation and fire history. Telowie had been subject to a prescribed burn approximately 18 months earlier, while a fire at Mount Remarkable was planned for the near future which offered the opportunity for both pre- and post-burn assessment. Abundance, height, vigour and leaf size of regrowth were recorded on three burnt and five unburnt sites at each reserve. Strong post-fire regrowth of L. saxatilis was observed on all burnt sites, while unburnt sites had less or no new growth. At Mount Remarkable, analysis by ordination of individual morphology data clearly indicated the presence of regrowth from resprouting adults and seedlings. At Telowie, on the other hand, a fairly uniform seedling population was found. This regeneration behaviour of L. saxatilis is consistent with a facultative resprouter. Over the two-year monitoring period, growth and mortality led to significant changes in the populations...

Predicting fire regimes and their ecological effects in spatially complex landscapes

Cary, Geoffrey John
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Thesis (PhD); Doctor of Philosophy (PhD)
EN_AU
Relevância na Pesquisa
37.07%
Fire occurrence influences the distribution of plant species, and dynamics of plant populations, either independently from other factors or in interaction with them. Numerous studies have identified the effects of components of fire regimes (frequency, intensity and season of occurrence) on the population dynamics of individual plant species and the floristic composition of plant communities, both in Australia and in other fire-prone countries. Nevertheless, there has been considerably less research into understanding the causes of spatial variation in fire regimes and this will likely result in a major obstacle for the development of vegetation theory. Research into spatial and temporal patterns of fire regime and determining the extent to which this type of variation results in variation in the occurrence of plant species and hence the composition of plant communities, can help overcome this obstacle. Two hypotheses are constructed and addressed. They are:- (i) that because of the influence of a sites' neighbourhood, variation in fire regimes will exist for any particular set of sites that occupy a particular part of environmental space and are therefore otherwise similar, and (ii) that this variation in fire regimes will result in patterns of plant species occurrence and hence demonstrate that landscape induced pattems of fire regime are a fundamentally important component in determining the realised niche of plant species in spatially complex landscapes. These hypotheses are examined for a spatially complex landscape in the Australian Capital Territory region...

Paleoecological Reconstruction of the Holocene Fire Regime at Mud Lake, Eastern Ontario, near St. Lawrence Islands National Park

Ellwood, Suzanne Margaret
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 3768458 bytes; application/pdf
EN; EN
Relevância na Pesquisa
37.03%
Wildfire is an ecological disturbance that plays an important role in ecosystem function and interacts with climate and vegetation, relationships that may be altered by ongoing climate change. Insights from paleoecology can provide context for environmental change, including the natural range of variability. Here, the Holocene fire history of a small watershed in eastern Ontario, Canada is reconstructed. A high-resolution macroscopic charcoal series was derived from the lacustrine sediment of Mud Lake, north of Gananoque, Ontario and within the Frontenac Arch. Analysis of the charcoal record estimates a mean fire-return-interval (FRI) of 175 yr/fire around Mud Lake during the Holocene, and similar mean FRIs during different time periods indicates that it has been a largely stationary fire regime. The analysis suggests that fire activity may have recently increased, but a lack of documentary fire records for the area leaves this uncertain. There is no indication that humans have significantly impacted the fire regime, though anthropogenic ignition could have played a role in the area’s recent fires. The fire regime around Mud Lake does not appear to have shifted in association with major changes in regional vegetation. Fire activity does correlate with some paleoclimate trends. The estimated fire frequency decreased around 7500 yr BP...

How fire history, fire supression practices and climate change affect wildfire regimes in Mediterranean landscapes

Brotons Alabau, Lluís; Aquilué, Núria; Càceres, Miquel de; Fortin, Marie-Josée; Fall, Andrew
Fonte: Universidade Autônoma de Barcelona Publicador: Universidade Autônoma de Barcelona
Tipo: Artigo de Revista Científica Formato: application/pdf
Publicado em //2013 ENG
Relevância na Pesquisa
37.07%
Available data show that future changes in global change drivers may lead to an increasing impact of fires on terrestrial ecosystems worldwide. Yet, fire regime changes in highly humanised fire-prone regions are difficult to predict because fire effects may be heavily mediated by human activities We investigated the role of fire suppression strategies in synergy with climate change on the resulting fire regimes in Catalonia (north-eastern Spain). We used a spatially-explicit fire-succession model at the landscape level to test whether the use of different firefighting opportunities related to observed reductions in fire spread rates and effective fire sizes, and hence changes in the fire regime. We calibrated this model with data from a period with weak firefighting and later assess the potential for suppression strategies to modify fire regimes expected under different levels of climate change. When comparing simulations with observed fire statistics from an eleven-year period with firefighting strategies in place, our results showed that, at least in two of the three sub-regions analysed, the observed fire regime could not be reproduced unless taking into account the effects of fire suppression. Fire regime descriptors were highly dependent on climate change scenarios...

Autonomous field-deployable wildland fire sensors

Kremens, Robert; Faulring, Jason; Gallagher, A.; Seema, Adolph; Vodacek, Anthony
Fonte: International Association of Wildland Fire Publicador: International Association of Wildland Fire
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
46.97%
An Autonomous Fire Detector (AFD) is a miniature electronic package combining position location capability [using the Global Positioning System (GPS)], communications (packet or voice-synthesized radio), and fire detection capability (thermal, gas, smoke detector) into an inexpensive, deployable package. The AFD can report fire-related parameters, like temperature, carbon monoxide concentration, or smoke levels via a radio link to firefighters located on the ground. These systems are designed to be inserted into the fire by spotter planes at a fire site or positioned by firefighters already on the ground. AFDs can also be used as early warning devices near critical assets in the urban–wildland interface. AFDs can now be made with commercial off-the-shelf components. Using modern micro-electronics, an AFD can operate for the duration of even the longest fire (weeks) using a simple dry battery pack, and can be designed to have a transmitting range of up to several kilometers with current low power radio communication technology. A receiver to capture the data stream from the AFD can be made as light, inexpensive and portable as the AFD itself. Inexpensive portable repeaters can be used to extend the range of the AFD and to coordinate many probes into an autonomous fire monitoring network.; This article may also be found on the publisher's website at: http://www.publish.csiro.au/nid/114/paper/WF02055.htm; The National Aeronautics and Space Administration supported this work under Grant NAG5-10051. Its financial support has been greatly appreciated.

DEVELOPMENT OF A FIRE DANGER INDEX FOR EUCALYPT PLANTATIONS IN THE NORTHERN COAST OF BAHIA, BRAZIL; DEVELOPMENT OF A FIRE DANGER INDEX FOR EUCALYPT PLANTATIONS IN THE NORTHERN COAST OF BAHIA, BRAZIL

White, Benjamin Leonardo Alves; Universidade Federal de Sergipe; White, Larissa Alves Secundo; Universidade Federal de Sergipe; Ribeiro, Genésio Tâmara; Universidade Federal de Sergipe; Fernandes, Paulo Alexandre Martins; Universidade de Trás-os-Montes
Fonte: FUPEF DO PARANÁ Publicador: FUPEF DO PARANÁ
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Artigo Avaliado pelos Pares Formato: application/pdf
Publicado em 08/10/2013 POR
Relevância na Pesquisa
37.05%
Economic losses caused by fires in commercial plantations of eucalypt forest has led to the development of new fire-fighting systems and methodologies. This study aimed to develop a fire danger index for eucalypt plantations in the Copener Forestal Ltda. areas located in the north coast of Bahia, Brazil, in order to improve fire control efforts. For this purpose, eight years of meteorological data were collected and correlated to forest fire occurrence through multivariate logistic regression. The proposed model (White Model) presented a better statistical performance than other models generally used in Brazil, recommended for operational use in focused area.Keywords: Fire danger rating; fire prevention; fire suppression; fire safety.; Economic losses caused by fires in commercial plantations of eucalypt forest has led to the development of new fire-fighting systems and methodologies. This study aimed to develop a fire danger index for eucalypt plantations in the Copener Forestal Ltda. areas located in the north coast of Bahia, Brazil, in order to improve fire control efforts. For this purpose, eight years of meteorological data were collected and correlated to forest fire occurrence through multivariate logistic regression. The proposed model (White Model) presented a better statistical performance than other models generally used in Brazil...