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Incendios de la cobertura vegetal en Colombia.
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... In Colombia, various studies (e.g., [43,75]) have i cated that meteorological conditions characterized by high temperatures, coupled w low RH, minimal rainfall, and strong winds, create favorable circumstances for the em gence of wildfires. These fires not only impact vegetation and ecosystems ( [10,17,46]) also affect the air quality of many cities in the country due to long-range trans ( [41,76,77]). These findings align with Figure 5, which illustrates the distinctions betw days with wildfires (dark red boxes) and those without (green boxes). ...
... In Colombia, various studies (e.g., [43,75]) have indicated that meteorological conditions characterized by high temperatures, coupled with low RH, minimal rainfall, and strong winds, create favorable circumstances for the emergence of wildfires. These fires not only impact vegetation and ecosystems ( [10,17,46]) but also affect the air quality of many cities in the country due to long-range transport ( [41,76,77]). These findings align with Figure 5, which illustrates the distinctions between days with wildfires (dark red boxes) and those without (green boxes). ...
Recent times have witnessed wildfires causing harm to both ecological communities and urban-rural regions, underscoring the necessity to comprehend wildfire triggers and assess measures for mitigation. This research hones in on Cartagena del Chairá, diving into the interplay between meteorological conditions and land cover/use that cultivates a conducive environment for wildfires. Meteorologically, the prevalence of wildfires is concentrated during boreal winter, characterized by warm and dry air, strong winds, and negligible precipitation. Additionally, wildfires gravitate toward river-adjacent locales housing agriculture-linked shrubs, notably in the northern part of the zone, where a confluence of land attributes and meteorological factors synergize to promote fire incidents. Employing climate scenarios, we deduced that elevated temperature and reduced humidity augment wildfire susceptibility, while wind speed and precipitation discourage their propagation across most scenarios. The trajectory toward a warmer climate could instigate fire-friendly conditions in boreal summer, indicating the potential for year-round fire susceptibility. Subsequently, via machine-learning-driven sensitivity analysis, we discerned that among the scrutinized socioeconomic variables, GINI, low educational attainment, and displacement by armed groups wield the most substantial influence on wildfire occurrence. Ultimately, these findings converge to shape proposed wildfire mitigation strategies that amalgamate existing practices with enhancements or supplementary approaches.
... Un tema preocupante es que las causas de la proliferación por la actividad humana en estas últimas décadas sobrepasan la capacidad de recuperación natural. Con esto, se aprecian cambios en los regímenes de fuego por influencia humana (Cerano-Paredes et al., 2016;Guitian Rivera, 1999;Kauffman, 1991;Parra Lara, 2011;Rodrígues et al., 2004). A la vez, ha crecido el interés, general y regional, la multidisciplinariedad y la investigación sobre las causas, implicaciones y algunos aspectos relacionados con los incendios; tanto en la cantidad de estudios (Harnecker et al., 2020;Rodrígues et al., 2004) como en las técnicas innovadoras desde la inteligencia artificial y sensores remotos para su pronta detección y previsión (Castillo Sarasty, 2021). ...
(Introducción):
Algunas variables ayudan a explicar la Superficie Forestal Afectada por Incendios (SFAI) que si bien, se conocen intuitivamente, no se han cuantificado para estimar su importancia en la prevención al combate de los incendios forestales.
(Objetivo):
Plantear un modelo estadístico que demuestre los determinantes de la SFAI y, con ello, aportar información inicial para el fortalecimiento de un esquema para prevención de incendios.
(Metodología):
Se integraron dos técnicas estadísticas: análisis multivariado de componentes principales y datos panel para entender la relación entre dichas variables intuitivas sobre número de incendios, detección, llegada, temperatura y duración, sobre la SFAI.
(Resultados):
Sugieren que en 11 entidades federativas de México (Región Centro-Occidente) hay una relación entre la cantidad y duración de incendios, más que proporcional para la cantidad de incendios (1.28) y menos que proporcional para la duración de estos (0.52), en relación con la SFAI.
(Conclusiones):
Este modelo puede tener aplicaciones en la planificación de acciones y esquemas para la protección de ecosistemas forestales y la asignación de recursos (humanos, equipo y materiales) más eficaz y eficiente a fin de prevenir y reducir los incendios forestales.
... In Colombia, wildfire events are highly correlated with the spatial distribution of the territories [3]. These mainly occur during the dry season and are strongly related to the expansion of agriculture and livestock frontiers [4]. ...
Citation: Casallas, A.; Jiménez-Saenz, C.; Torres, V.; Quirama-Aguilar, M.; Lizcano, A.; Lopez-Barrera, E.A.; Ferro, C.; Celis, N.; Arenas, R. Design of a Forest Fire Early Alert System through a Deep 3D-CNN Structure and a WRF-CNN Bias Correction.
... In Colombia, wildfire events are highly correlated with the spatial distribution of the territories [3]. These mainly occur during the dry season and are strongly related to the expansion of agriculture and livestock frontiers [4]. ...
Throughout the years, wildfires have negatively impacted ecological systems and urban areas. Hence, reinforcing territorial risk management strategies against wildfires is essential. In this study, we built an early alert system (EAS) with two different Machine Learning (ML) techniques to calculate the meteorological conditions of two Colombian areas: (i) A 3D convolutional neural net capable of learning from satellite data and (ii) a convolutional network to bias-correct the Weather Research and Forecasting (WRF) model output. The results were used to quantify the daily Fire Weather Index and were coupled with the outcomes from a land cover analysis conducted through a Naïve-Bayes classifier to estimate the probability of wildfire occurrence. These results, combined with an assessment of global vulnerability in both locations, allow the construction of daily risk maps in both areas. On the other hand, a set of short-term preventive and corrective measures were suggested to public authorities to implement, after an early alert prediction of a possible future wildfire. Finally, Soil Management Practices are proposed to tackle the medium- and long-term causes of wildfire development, with the aim of reducing vulnerability and promoting soil protection. In conclusion, this paper creates an EAS for wildfires, based on novel ML techniques and risk maps.
... During the last 20 years in Colombia, the majority of fire activity has been associated with the tropical dry forests (hereafter TDF) cover of the inter-Andean valleys, the Orinoco and the Caribbean region (Armenteras, González-Alonso, & Aguilera, 2009;Armenteras et al., 2011;Pizano & García, 2014;Etter, Andrade, Amaya, & Arévalo, 2015;Pausas & Ribeiro, 2017). However, little is known about the capacity of Colombian TDF species to regenerate after wildfires (Vieira & Scariot, 2006;Pizano & García, 2014; Rodríguez-Buritica, Aguilar-Garavito, & Norden, 2017). ...
In fire-influenced ecosystems, some plant species have the ability to recover, germinate, and to establish after a fire; however, their proportion and dominance varies between sites. The objective of this work was to evaluate natural regeneration following a fire in a tropical dry forest located in the Upper Magdalena River Valley in Colombia. In that way, all seedlings and saplings of woody species were recorded, 1.5 years after a fire, in 75 2x2-m plots installed in burned and unburned forest sites, as well as in forest gaps. Results showed that although abundance was higher in the burned sites, the species richness was lower than in unburned areas. Based on the regeneration response of the species, we identified three groups of plants: 1) fire-stimulated, 2) fire-tolerant, and 3) fire-sensitive species, which means that this tropical dry forest has species with the ability to recover, germinate, and establish after a fire. These three groups of plant species should be considered in restoration programs in light of future and more frequent forest fires due to climate change.
... En Colombia los estudios sobre el comportamiento del fuego en la vegetación, se han enfocado principalmente en mapeos y teledetección satelital a gran escala de coberturas vegetales (Parra 2011, Armenteras 2009), y en evaluaciones de inflamabilidad de la madera con fines industriales, sin tener en cuenta las partes generalmente más sensibles al fuego, como lo son el follaje y las ramas (Doran et al. 2004). ...
La inflamabilidad de 11 especies de plantas cultivadas en la ciudad de Medellín-Colombia, se evaluó empleando las variables tiempo de ignición y tiempo de sostenibilidad de la llama, con el objetivo conocer su susceptibilidad a incendiarse y consumirse, utilizando la metodología propuesta por Valette, exponiendo superficies foliares vivas a una fuente de calor externa constante a 420 °C y condiciones controladas. De las especies evaluadas, Costus guanaiensis Rusby y Clusia multiflora Kunth presentaron mayor tiempo de ignición, y menor valor en la sostenibilidad, es decir, presentan tanto un efecto retardante a la incidencia y propagación de incendios, por tanto se recomiendan como cortafuegos especialmente en zonas con alta frecuencia e impacto de incendios.
Palavras-chave:
fireproofing; flame sustainability; time to ignition
... Un tema preocupante es que las causas de la proliferación por la actividad humana en estas últimas décadas sobrepasan la capacidad de recuperación natural. Con esto, se aprecian cambios en los regímenes de fuego por influencia humana (Cerano-Paredes et al., 2016;Guitian Rivera, 1999;Kauffman, 1991;Parra Lara, 2011;Rodrígues et al., 2004). A la vez, ha crecido el interés, general y regional, la multidisciplinariedad y la investigación sobre las causas, implicaciones y algunos aspectos relacionados con los incendios; tanto en la cantidad de estudios (Harnecker et al., 2020;Rodrígues et al., 2004) como en las técnicas innovadoras desde la inteligencia artificial y sensores remotos para su pronta detección y previsión (Castillo Sarasty, 2021). ...
Introducción]: Algunas variables ayudan a explicar la Superficie Forestal Afectada por Incendios (SFAI) que si bien, se conocen intuitivamente, no se han cuantificado para estimar su importancia en la prevención al combate de los incendios forestales. [Objetivo]: plantear un modelo estadístico que demuestre los determinantes de la SFAI y, con ello, aportar información inicial para el fortalecimiento de un esquema para prevención de incendios. [Metodología]: se integraron dos técnicas estadísticas: análisis multivariado de componentes principales y datos panel para entender la relación entre dichas variables intuitivas sobre número de incendios, detección, llegada, temperatura y duración, sobre la SFAI. [Resultados]: sugieren que en 11 entidades federativas de México (Región Centro-Occidente) hay una relación entre la cantidad y duración de incendios, más que proporcional para la cantidad de incendios (1.28) y menos que proporcional para la duración de estos (0.52), en relación con la SFAI. [Conclusiones]: este modelo puede tener aplicaciones en la planificación de acciones y esquemas para la protección de ecosistemas forestales y la asignación de recursos (humanos, equipo y materiales) más eficaz y eficiente a fin de prevenir y reducir los incendios forestales.
... It could be said that today the phenomenon is the expression of the degradation of natural fire regimes in most terrestrial ecosystems. Unfortunately, for decades a vision based on mistaken assumptions prevailed in the imagination of states, governments and the general public in different countries, such as the following: a) considering fires of vegetation cover as a phenomenon of fundamentally natural origin and local impacts restricted to vegetation, b) overestimating the capacity of nature to restore affected ecosystems (Armenteras et al., 2011). ...
Analyses of the historical behavior of forest fires provide the basis for effective fire management programs. This descriptive research aimed to analyze when, where and why forest fires occurred in Santa Ana canton, Manabí province, Ecuador, during the period 2012-2018. The data were provided by the Fire Department of that locality. The analysis was carried out considering a spatiotemporal context (years, months, days of the week, localities and vegetation cover). Statistical analyses were carried out with SPSS Statistics for Windows (version 22.0). A significance level of 0.05 was used. In the analyzed period, 91 losses were reported, corresponding to the year 2016 the highest percentage (38.46 %). From July to January 94.50 % of the total number of fires were recorded, associated with low rainfall and increased use of fire by farmers to clear the land. During the day, the highest number of events was recorded from 14:00 to 16:00 hours (27.47 %). In cases where the parish and vegetation cover were specified,the highest percentages corresponded to Ayacucho and weeds with 54.05 and 26.37 %, respectively. The work allowed to establish temporal and spatial patterns of fire occurrence and its causality, constituting an important and relevant contribution on when,where and why fires occur in the canton of Santa Ana, information that can be used by decision makers of integrated fire management activities.
El fuego es un elemento natural importante en la evolución y desarrollo de la
humanidad. No obstante, cuando tiene un manejo inadecuado y se torna
incontrolable, se producen los incendios, los que ocasionan pérdidas ambientales,
sociales y económicas. En el presente estudio se zonificó las áreas susceptibles a
incendios de cobertura vegetal en la subcuenca del río Mataquí, en el cantón
Pimampiro. Se identificaron nueve factores biofísicos que intervienen en la
generación de incendios: temperatura, precipitación, déficit hídrico,
evapotranspiración, cobertura de suelo, cercanía a vías, pendiente, orientación del
terreno y altitud, a través de la aplicación de la metodología multicriterio. Estos
factores fueron ponderados y aplicados en una ecuación de susceptibilidad
mediante el uso de Sistemas de Información Geográfica. Los resultados mostraron
que la subcuenca del río Mataquí presenta 5 rangos de susceptibilidad: nula o muy
baja, baja, moderada, alta y extrema. Las categorías extrema y alta ocupan el 26%
del área de estudio, siendo las coberturas de cultivos y pastos las más susceptibles.
Estado del conocimiento de la ecología del fuego en Colombia: síntesis de hallazgos y aplicaciones.
Counterurbanization has been considered as a chaotic concept in the academic literature. It entails demographic movement and deconcentration in some urban areas and appears to be a new process of populations spatial distribution and the definition of a new settlement pattern which may exceed the Central Place Theory. The results of this process and demographic movement have led to societal divesification and even to the emergence of new classes in the countryside and new urban-rural relationships. In such circumstances it is not surprising that both problems and opportunities arise when it comes to making territory planning policies. This paper focuses on analizing the international scientific literature on Counterurbanization -particularly that of Anglosaxon countries- with an aim to contribute to the search of meaning in the arguments which support the definition of Counterurbanization and to foster its research both in Spain and Latinamerica.
In this paper we analyse the interactions between fire severity (plant damage) and plant regeneration after fire by means of remote sensing imagery and a field fire severity map. A severity map was constructed over a large fire (2692 ha) occurring in July 1994 in the Barcelona province (north-east of Spain). Seven severity classes were assigned to the apparent plant damage as a function of burning intensity. Several Landsat TM and MSS images from dates immediately before and after the fire were employed to monitor plant regeneration processes as well as to evaluate the relationship with fire severity observed in situ . Plant regeneration was monitored using NDVI measurements (average class values standardized with neighbour unburned control plots). Pre-fire NDVI measurements were extracted for every plant cover category (7), field fire severity class (7), and spatial cross-tabulation of both layers (33) and compared to post-fire values. NDVI decline due to fire was positively correlated with field fire severity class. Results show different patterns of recovery for each dominant species, severity class and combination of both factors. For all cases a significant negative correlation was found between damage and regeneration ability. This work leads to a better understanding of the influence of severity, a major fire regime parameter on plant regeneration, and may aid to manage restoration on areas burned under different fire severity levels.
Tropical and subtropical areas present the vast majority of contemporary global fires. Despite the human origin of most of these fires, little is known of how environmental and socioeconomic variables contribute to the spatial patterns of fire incidence and burned areas. The tropical Mexican State of Chiapas represents a good case study to analyze these interactions, due to the availability of official data, and its similarities to other tropical countries, in terms of environmental and socioeconomic characteristics. This study evaluates the relative importance of human-related and environmental variables in determining the distribution of the number of fires and area burned in the tropical State of Chiapas in years of normal and extreme climatic conditions (non-El Niño vs. El Niño). We have searched for causal relationships among fire, environmental, and socioeconomic variables in Chiapas using path analysis. Results of this study show a major importance of environmental variables in non-El Niño years, suggesting that the status of the vegetation was the main cause determining fire ignition and fire spread in these years. Contrarily, the observed trends in the El Niño period indicate that fire trends were mainly determined by the presence of ignition agents. In these El Niño years, vegetation is so severely water stressed that, when fire starts, all vegetation types burn, regardless of their flammability properties. The main vegetation types affected by fire in non-El Niño years were the most flammable ones, such as pine-oak communities, while rainforests burned the most in El Niño years. Altitude, pine-oak communities, and poverty levels played major roles in the arboreal fire incidence in non-El Niño years, whereas the distribution of pastures appeared as an important variable determining arboreal fire incidence in El Niño years. When all fires were considered (affecting any vegetation layer), almost identical trends were observed, with the incorporation of a new variable influencing the area burned: density of infrastructure. The results of this study strengthen the importance of El Niño years in the conservation of rainforest ecosystems and suggest the existence of synergistic effects involving fires, fragmentation, and certain elements of the landscape, such as cattle pastures, in tropical areas.
Resumen La investigación de los incendios forestales tiene como finalidad tres objetivos fundamentales: La determinación de las causas, la identificación de las situaciones de riesgo que las producen y la aplicación y divulgación de medidas preventivas adecuadas a cada una de ellas. Para llevarlos a cabo, es necesario un seguimiento exhaustivo de los distintos sucesos, recogidos en un archivo de datos histórico sobre las causas ocurridas en un ámbito geográfico determinado, y ligados a unas actividades humanas concretas. El análisis de toda la información obtenida nos permitirá detectar y definir las distintas situaciones de riesgo, punto de partida para elaborar el programa preventivo adecuado a aplicar y reducir el peligro potencial.
The risks associated with managing areas within the wildland-urban interface (WUI) are of increasing concern in natural resource management. One of the particular problems is the increased threat to life and property from catastrophic wildfires. The purpose of this analysis is to aid federal priority-setting within the National Fire Plan to help address WUI issues. In this analysis, we attempt to identify potential WUI areas based on population density using the aid of a Geographic Information System (GIS). Populations were classified into 5 population density categories at the national and state levels as well as within and surrounding federal lands.
Forest fires are increasing every year in Portugal. Trying to understand more about their causes, we collected available forest fires data, as well as agroforestry and socio-economic parameters considered to be closely related to them, in all the 274 administrative regions (councils). Using multivariate analysis (principal components analysis and classification) we established 8 groups of councils defined by the identity of response of the analysed variables. We were, therefore, able to determine which parameters mainly influenced each group, and that knowledge could be a starting point to fire prevention.
As a significant source of trace gases and particulate matter to the atmosphere, biomass burning plays an important role in climate change and atmospheric chemistry at regional and global scales. The burned area is a critical parameter in estimating fire emissions. Recently, multiyear global burned area products with medium spatial resolution (1 km or 500 m) have been released, including the L3JRC product and the Collection 5 Moderate-Resolution Imaging Spectroradiometer (MCD45A1) product. In this study, we compare the spatial distribution and temporal pattern of L3JRC and MCD45A1 burned areas over 7 fire years from 1 April 2000 to 31 March 2007. For these 7 fire years, L3JRC gave global burned areas of 3.89, 4.32, 3.53, 4.43, 3.81, 3.60, and 4.51 million km2, and MCD45A1 gave values of 3.44, 3.33, 3.57, 3.38, 3.52, 3.39, and 3.61 million km2, respectively. The L3JRC product showed persistent burning activity from April to October, whereas the burned area according to MCD45A1 often peaked in August and December at the global scale. For most continents, the L3JRC and MCD45A1 burned areas compared very well during the fire season; however, for the period outside the fire season, L3JRC generally reported a significantly larger burned area than did MCD45A1. The burned areas were examined according to the main vegetation classes given by the GlobCover product. Validation of the L3JRC and MCD45A1 burned areas was performed using data from ground-based measurements in Canada, the United States, Russia, and China. The results showed that MCD45A1 was more comparable to reference data, although it often underestimated in the boreal forests. L3JRC generally exhibited significant overestimation in these areas.