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RESUMEN Los ecosistemas tropicales albergan una gran parte de la biodiversidad mundial y a pesar de ello están siendo transformados por el cambio de uso de la tierra a un ritmo sin precedentes. La conversión de la cobertura de la tierra y el mantenimiento de pastos y áreas para cultivos en Latino América están altamente relacionados con el uso del fuego. El origen de los incendios y sus causas son numerosos y en la región es clara su asociación de forma directa o indirecta con actividades humanas. Suramérica está siendo cada vez más afectada por los incendios y desde el 2001 en todos los años se ha detectado actividad asociada al fuego. Los impactos de los incendios sobre los ecosistemas naturales son múltiples y varían en magnitud, pero se ha avanzado poco en su conocimiento. Este artículo presenta una recopilación del conocimiento que se tiene en ecología del fuego tropical en los tres países andinos del norte de Suramérica, mostrando los avances en los patrones espaciales y temporales de los incendios, los efectos sobre los ecosistemas y las dinámicas post incendio. Se evidencian grandes vacíos del conocimiento en la ecología del fuego de gran parte de los ecosistemas de esta región. ABSTRACT Tropical ecosystems harbor a large part of the world's biodiversity, yet they are being transformed at unprecedented rates by changes in land use. In Latin America, land cover conversion, and pastures and agricultural areas maintenance are strongly related with the use of fire. The source of fire and its causes are numerous and in the region there is an evident direct and indirect association with human activities. South America has been increasingly affected by fire occurrence; with fire events every year since 2001. The impacts of fires on natural ecosystems are multiple and vary in magnitude but little progress has been made to assess their extent. This article presents a review of current knowledge on tropical fire ecology in three Andean countries of northern South America, it provides an insight on the spatial and temporal patterns of fire, the effects over the ecosystems and post-fire dynamics. Large knowledge gaps about the fire ecology on several ecosystems in this region are evident.

Material Flow Analysis is a powerful tool, first time used in Costa Rica, to analyze the problems related to solid waste management in the district of Guápiles, in the province of Limon, Costa Rica. It is an analytical method to quantify flows and stocks of materials or substances in a well-defined system, allowing the visualization of solid waste and the actors involved in the process. The methodology used for the investigation was the characterization of residues of one hundred four houses and forty-nine shops, taking as reference the “Guide of interpretation of the methodology for the realization of studies of generation and composition of ordinary waste” of the CYMA program of the year 2012. In addition, surveys were conducted in the residential and commercial sector, as well as interviews with solid waste managers of the municipality of Pococí, and companies that collect recyclable materials and private collectors. Additionally, the analysis of materials received from the waste recovery campaigns for recycling. With this analysis, it was possible to identify the total amounts of solid waste being burned (283.80 tons / year), burials of organic matter (1 204.89 tons / year), glass burials (4.71 tons / year), recovery of solid waste for recycling, including less common flows such as electronic waste and metal scrap (2 115.35 tons / year). Furthermore, it was found that 7 408,04 tons / year had gone to Los Laureles sanitary landfill, and 1 225,44 tons/ year of illegal dumping. It was concluded that this tool could be used when making decisions in relation to the improvement of solid waste management systems. Ante la problemática latente en el manejo de residuos sólidos en el distrito de Guápiles, se plantea la utilización para el análisis de la situación de la herramienta denominada: “Análisis de Flujo de Materiales”, la cual es utilizada por primera vez en Costa Rica en el año 2018, año en que se realiza la presente investigación. Esta herramienta permite visualizar los flujos de los residuos sólidos dentro de un sistema para identificar los principales problemas existentes con base en la distribución de las masas de los materiales en los sitios de disposición final definidos por la población, así como los diversos actores sociales involucrados en el proceso. La metodología para la investigación fue la caracterización de residuos de ciento cuatro viviendas y cuarenta y nueve comercios, tomando como referencia la “Guía de interpretación de la metodología para la realización de estudios de generación y composición de residuos ordinarios” del programa CYMA del año 2012. Además, encuestas realizadas al sector residencial y comercial, entrevistas a gestores de residuos sólidos tanto de la municipalidad de Pococí como a empresas de acopio de materiales valorizables y recolectores privados. Finalmente, se recibieron y clasificaron materiales producto de las campañas de recuperación de residuos para el reciclaje. De esta manera se pudo identificar la totalidad de los residuos sólidos destinados a quemas (283,80 ton/año), entierros de materia orgánica (1 204,89 ton/año), entierros de vidrio (4,71 ton/año), recuperación de residuos sólidos para el reciclaje, incluyendo los flujos menos comunes como la recuperación de residuos electrónicos y chatarra (2 115,35 ton/año) y las 7 408,04 ton/año destinadas al Relleno Sanitario Los Laureles, de las cuales 1 225,44 ton/año corresponden a descargas ilegales en el centro del distrito. Utilizando esta herramienta, es posible tomar decisiones basadas en el mejoramiento del sistema de gestión de residuos sólidos que es provisto en el distrito por los sectores: municipal, privado e informal, identificados en el proceso de recolección de datos.

As terras indígenas brasileiras formam o maior mosaico de áreas protegidas do país, sendo fundamentais para a conservação ambiental. Apesar disso, nem sempre foram alvo dos programas governamentais relacionados aos incêndios florestais. Quando atendidas, receberam ações isoladas e desarticuladas, que não foram avaliadas ou monitoradas adequadamente. Essa realidade mudou recentemente com a criação de um programa específico para as comunidades indígenas, baseado na valorização da mão de obra local e no conhecimento tradicional, por meio do manejo integrado do fogo. O objetivo desse artigo é apresentar um histórico das atividades de prevenção e combate aos incêndios florestais nas terras indígenas brasileiras e os principais resultados do Programa Brigadas Federais, implementado pela Fundação Nacional do Índio e pelo Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis, por meio do Centro Nacional de Prevenção e Combate aos Incêndios Florestais (Prevfogo). Esses resultados demonstram a eficiência das brigadas indígenas e a relevância do conhecimento tradicional na implementação do manejo integrado do fogo, enfatizando a importância do aspecto sociocultural como fator de sucesso para a abordagem do tema. Além disso, o Programa Brigadas Federais desenvolveu procedimentos técnicos e administrativos que ordenaram as ações de proteção contra os incêndios florestais em territórios tradicionais, permitindo a expansão eficiente das áreas atendidas. Essa expansão é uma excelente oportunidade para apoiar políticas de conservação da biodiversidade ou de combate e mitigação das mudanças climáticas globais. Entretanto, proteger essas imensas áreas ainda é um desafio que exige ações de estruturação dos órgãos responsáveis, articulação interinstitucional, mudanças na legislação, consolidação da integração do aspecto sociocultural e pagamento pelos serviços ambientais prestados. Las tierras indígenas brasileñas configuran el mayor mosaico de áreas protegidas del país y son fundamentales para la conservación del ambiente. A pesar de eso, no siempre fueron objeto de programas gubernamentales relacionados con los incendios forestales. Cuando asistidas, recibieron acciones aisladas y desarticuladas sin adecuada evaluación ni seguimiento. Hubo un cambio recién con la creación de programa específico para comunidades indígenas, basado en la valorización de la mano de obra local y el conocimiento tradicional, a través del manejo integral del fuego. Este artículo presenta las actividades de prevención y combate de incendios forestales en tierras indígenas y los principales resultados del Programa Brigadas Federales, implementado por la Fundación Nacional Indígena y el Instituto Brasileño de Medio Ambiente y Recursos Naturales Renovables, a través del Centro Especializado Prevfogo. Los resultados demuestran la relevancia y eficiencia del conocimiento tradicional y de las brigadas indígenas en la implementación del manejo integral del fuego, señalando la importancia del aspecto sociocultural como factor exitoso para abordar el tema del fuego. El Programa de Brigadas Federales desarrolló procedimientos técnicos y administrativos que ordenaron las acciones de protección contra incendios forestales en territorios tradicionales, permitiendo la expansión eficiente de las áreas atendidas. Estos avances son una excelente oportunidad para apoyar políticas para conservar la biodiversidad, combatir y mitigar el cambio climático global. Sin embargo, proteger estas inmensas áreas es un desafío que requiere acciones estructuradas y articuladas de los órganos responsables, cambios en la legislación, consolidación de la integración del aspecto sociocultural y pago por los servicios ambientales prestados. The brazilian indigenous lands are fundamental for environmental conservation, shaping the largest mosaic of protected areas in the country. In spite of that, they were rarely targeted in governmental programs related to wildfires. Even when attended, they received isolated and disconnected actions with no proper evaluation nor monitoring. Recently there was a change by the creation of a specific program for indigenous communities, based on the empowerment of local labor force and traditional knowledge, through integrated fire management approach. This article aims to record an overview of the activities for preventing and fighting wildfires in indigenous lands and the main outcomes of the Federal Brigade Program, implemented by the National Indian Foundation and the Brazilian Institute for the Environment and Renewable Natural Resources, through the Specialized Center Prevfogo. The results highlight the importance and efficiency of traditional knowledge and indigenous brigades in the implementation of integrated fire management, pointing out the significance of the socio-cultural aspect as a successful element for addressing the fire issue. The Federal Brigade Program developed technical and administrative procedures that set up the protection actions against wildfires in traditional territories, allowing an efficient expansion of the areas assisted. This advance is an outstanding opportunity to support policies to preserve biodiversity and mitigate global climate change. However, to protect these immense areas is still a challenge that requires structuring actions by the responsible agencies, interinstitutional articulation, changes in legislation, consolidation of the socio-cultural integration element and payment for environmental services provided.

Incendios - Quemas

Soils are one of the largest terrestrial pools of carbon, yet there is still little understanding of spatial variability for ecosystems in the tropics. Fire plays an important role in Neotropical savannas ecosystems and significantly contribute to global greenhouse gas (GHG) fluxes. Nevertheless, the impacts of burning on soil carbon is still uncertain in Latin America. We compared soil organic carbon (SOC) in the first 20 cm depth in savannas in pre and post fire conditions along a forests-savanna edge typically present in these landscapes of the northern South America. We established 8 transects of 20 m longitude along the border with 1m2 plots sampled every 4 m. SOC pre-disturbance was on average 1.794 (±SE 0.043) and the minimum value found (1.08%) was registered 6 months after the burning. Our results show that both the influence of the distance to the edge and the time of burning affect negatively the SOC and also there is a significant interaction between both variables. Our results provide improved estimates of the effect of fire on soil carbon stocks and its highly dynamic nature. We believe these finding will be a step to help better estimate GHG in this type of heterogeneous landscapes. Further it provides a tool for understanding C dynamics under a climate change context with predicted increased fire frequency, extent and severity. Soils are one of the largest terrestrial pools of carbon, yet there is still little understanding of spatial variability for ecosystems in the tropics. Fire plays an important role in neotropical savannas ecosystems and significantly contribute to global greenhouse gas (GHG) fluxes. Nevertheless the impacts of burning on soil carbon is still uncertain in Latin America. We compared soil organic carbon (SOC) in the first 20 cm depth in savannas in pre and post fire conditions along a forests-savanna edge typically present in these landscapes of the northern South America. We established 8 transects of 20 m longitude along the border with 1m2 plots sampled every 4 m. SOC pre-disturbance was on average 1.794 (±SE 0,043) and the minimum value found (1.08%) was registered 6 months after the burning. Our results show that both the influence of the distance to the edge and the time of burning affect negatively the SOC and also there is a significant interaction between both variables. Our results provide improved estimates of the effect of fire on soil carbon stocks and its highly dynamic nature . We believe these finding will be a step to help better estimate GHG in this type of heterogeneous landscapes. Further it provides a tool for understanding C dynamics under a climate change context with predicted increased fire frequency, extent and severity.

High-altitude paramo grasslands are important for their biodiversity and the ecosystem services that they provide to Andean people, but they are sensitive to disturbances, such as fire. Understanding the ecological impacts of disturbance is critical for the effective management of paramos. Indicator species studies can provide a relatively efficient way to gain such understanding. Puya hamata is a flagship giant rosette plant and has potential as an indicator of recent paramo fire history. To determine population size structure, mortality, recruitment and growth rates of Puya hamata rosettes, all Puya plants in 400 m 2 plots were surveyed in 2008 and again one year later. Sixteen plots were recorded in both years, containing exactly 1000 plants. Mortality was very low during this period (0.6%). Only 27 new plants were recruited. Three different size distribution patterns were observed in the plots: (1) low plant numbers across all size ranges; (2) a single dominant peak in numbers at a particular size; (3) two dominant peaks in numbers at distinct sizes. Estimated life span of Puya hamata was 28 years based on growth rates, and growth rate declined beyond the size at which most rosettes reproduce. To investigate the impact of different fire intensities on Puya hamata mortality, 400 m 2 plots within a mosaic of unburned and burned patches of different fire intensities were surveyed one month after the fire. Fire mortality was low in the medium and high intensity plots, and fires selectively killed smaller plants rather than larger ones. No mortality was observed in the unburned and low intensity fire plots. It is proposed that Puya responds to burning with pulses of seedling recruitment during periods of open vegetation after fires and very little recruitment at other times. Therefore, surveys of Puya plants can reveal past fire events in their population size structure. The combination of sensitivity to fire at recruitment, low fire mortality rates afterwards, and a 28-year lifespan makes Puya hamata an ideal indicator species of recent fire history in paramos.

En este ensayo, pu­blicado en 1939, el au­tor hace un llamado contra la práctica, tan nefasta para la calidad de los suelos, de llevar a cabo quemas con el propósito de lim­piar los terrenos o por conceptos erróneos como el pensar que esta actividad potenciará las cualidades de cultivo del suelo.

26 pages, 9 figures, 113 references., [EN]: A review of the effects of wildfires on Mediterranean soils was carried out with special emphasis on the biogeochemical processes involved in soil C sequestration. Modifications to the composition and properties of soil humic substances and related resilient C-forms in soil resulting from fires were also discussed. The systematic effects of fires on soil organic matter (SOM) mainly involve changes to its solubility and colloidal properties, selective thermal degradation, structural condensation and the cyclization of soil C and N-forms. These effects represent an increase in the biogeochemical stability and chemical diversity of the SOM after the thermal generation of structures that are not found in soils unless they are affected by fire. Non-systematic effects also depend on local environmental constraints and on the great differences in fire intensities and propagation patterns. The effects of fire were also discussed, taking advantage of the results of laboratory simulation experiments. This approach is indispensable for differentiating fire intrinsic effects on soil from those produced by fire-induced inputs of charred necromass and the subsequent effects of soil erosion. In some cases, the characteristic properties acquired by post-fire soils can be explained in terms of molecular-level features of humic substances and, in particular, those concerning resistance to biodegradation, cation exchange capacity, N-availability, soil water repellence and aggregate stability., [ES]: En este trabajo se lleva a cabo una revisión sobre los efectos de los incendios forestales en los suelos mediterráneos, con especial énfasis sobre sus efectos en los procesos biogeoquímicos de acumulación o secuestro de C en el suelo. Asimismo, se revisan los efectos de los incendios sobre la composición y propiedades de las sustancias húmicas y otras formas resilientes de C en el suelo. Las principales efectos sistemáticos del fuego sobre la materia orgánica incluyen cambios en su solubilidad y propiedades coloidales, así como degradación térmica selectiva, condensaciones estructurales y ciclación de formas de C y N en el suelo. Estos efectos, en conjunto, se consideran responsables del aumento en la diversidad química de la materia orgánica debido a la generación térmica de nuevos compuestos inexistentes en los correspondientes suelos no afectados por el fuego. Además de ello, deben considerarse los efectos no sistemáticos del fuego, que dependen de las condiciones ambientales locales y la amplia diversidad de los tipos de incendios. También se discuten los resultados de estudios sobre efectos del fuego en experimentos de simulación en laboratorio, que constituyen una aproximación experimental indispensable para diferenciar los efectos intrínsecos de los incendios en el suelo de aquellos producidos por aportes de necromasa carbonizada. Finalmente, se revisan los efectos del fuego en la estructura molecular de las sustancias húmicas, que pueden ser asociadas con cambios en las propiedades de los suelos, en particular respecto a la resistencia a la biodegradación, capacidad de intercambio catiónico, disponibilidad de N, repelencia al agua y estabilidad de los agregados del suelo., [PO]: Neste estudo faz-se uma revisão dos efeitos dos incêndios florestais nos solos mediterrânicos dando particular enfase aos efeitos nos processos biogeoquímicos de acumulação e sequestro de C no solo. Por outro lado, revem-se os aspectos relacionados com os efeitos dos incêndios sobre a composição e propriedades das substâncias húmicas e outras formas resilientes de C no solo. Os principais efeitos sistemáticos do fogo sobre a matéria orgânica incluem alterações da sua solubilidade e propriedades coloidais, bem como degradação térmica selectiva e condensação e ciclagem das formas de C e N no solo. Estes efeitos representam um aumento da estabilidade biogeoquímica e da diversidade química da matéria orgânica do solo devido à formação térmica de novas estruturas e compostos inexistentes nos solos não afectados pelos fogos. Para além disso, consideram-se os efeitos não-sistemáticos dos fogos, que dependem das condições ambientais locais bem como da grande diferença de intensidade dos fogos e padrões da sua propagação. Apresentam-se também resultados sobre o efeito dos fogos em ensaios de simulação laboratorial, que constituem uma abordagem experimental indispensável para distinguir os efeitos intrísecos dos incêndios dos produzidos devido a inputs no solo de necromassa carbonizada. Finalmente, faz-se uma revisão dos efeitos do fogo na estrutura molecular das substâncias húmicas associados a alterações nas propriedades do solo, particularmente no que se refere à resistência à biodegradação, capacidade de troca catiónica, disponibilidade de N, caracteristícas hidrofóbicas e estabilidade dos agregados do solo., Financial support by the Spanish CICyT under grant CGL2008-04296.

Este trabajo contiene un análisis sobre la relación entre dos problemas medioambientales que pareciesen lejanos, pero que están estrechamente vinculados: los incendios forestales y el deterioro de la calidad del aire de las ciudades. Dicho análisis pretende demostrar las importantes repercusiones de los incendios forestales sobre la calidad del aire urbano y, además, las dificultades de la gestión pública de los incendios forestales en Colombia, lo que, por supuesto, afecta la pureza del aire. This paper contains an analysis of the relationship between two environmental problems that seem distant, but are closely linked: forest fires and the deterioration of air quality in cities. This analysis aims to demonstrate the important repercussions of forest fires on urban air quality and, in addition, the difficulties of public management of forest fires in Colombia, which, of course, affects the purity of the air.

El presente trabajo muestra experiencias en el uso de imágenes multisensores (TM/Landsat y JERS-1) para el inventario de biomasa de formaciones forestales y de sabanas, y como herramienta del monitoreo de las quemas que ocurren en estos tipos de vegetación en la región Amazónica. Se describen procedimientos metodológicos de adquisición de datos de biomasa vegetal de porte forestal y de las sabanas. Estos datos son relacionados con las informaciones espectro-texturales de las imágenes de satélite, con la finalidad de elaborar la cartografía de la biomasa por tipología vegetal. El efecto de las quemas y el nivel de intensidad de la pérdida parcial o total de biomasa está siendo investigado y descrito a partir de la verificación muestral en campo y en las imágenes ópticas o de radar. La posibilidad de un inventario sinóptico de la antropización de la tipología forestal, la cual viene acompañada de la acción de la deforestación, renovación de pastos implantados o naturales con el proceso tradicional de quema, es demostrado en áreas de los estados Mato Grosso, Rondónia, Roraima y Acre, que forman parte de la Amazonia brasilera., This study presents the experiences on the use of TM/Landsat and JERS-1 images for the inventory of areas covered by tropical rainforest and savanna in Brazilian Amazonia, within sections affected by burning, that is a common practice in tile land occupation. Feature extraction techniques such as image segmentation and modelling by linear mixture analysis are presented to show the capacity to discriminate those areas covered by natural vegetation, where land use activities started using the old-fashioned slash-and-burn pratices. Methods for field surveys to estimate the biomass of forest and savannas are described, as well as the procedure used for areas affected by fire, in order to define the intensity of burning by the analysis of physiognomic-structural features of vegetation.