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Id: lil-441196
Autor: Fearnside, Philip M.
Título: Desmatamento na Amazônia: dinâmica, impactos e controle / Deforestation in Amazonia: dynamics, impacts and control
Fonte: Acta amaz;36(3):395-400, jul.-set. 2006. graf.
Idioma: pt.
Projeto: Conselho Nacional de Desenvolvimento Científico e Tecnológico; . Instituto Nacional de Pesquisas da Amazônia.
Resumo: O desmatamento na Amazônia procede a um alto ritmo por várias razões, muitas das quais dependem de decisões do governo. O desmatamento leva à perda de serviços ambientais, que têm um valor maior que os usos pouco sustentáveis que substituem a floresta. Estes serviços incluem a manutenção da biodiversidade, da ciclagem de água e dos estoques de carbono que evitam o agravamento do efeito estufa. Retroalimentações entre as mudanças climáticas e a floresta, por meio de processos tais como os incêndios florestais, a mortalidade de árvores por seca e calor e a liberação de estoques de carbono no solo, representam ameaças para o clima, a floresta e a população brasileira. Eventos recentes indicam que o desmatamento pode ser controlado, tendo a vontade política, pois os processos subjacentes dependem de decisões humanas.

Deforestation in Amazonia proceeds at a rapid rate for various reasons, many of which depend on government decisions. Deforestation causes losses of environmental services that are more valuable than the short-lived uses that replace the forest. These services include maintenance of biodiversity, of water cycling and of the stocks of carbon that avoid further intensification of the greenhouse effect. Feedbacks between climatic changes and the forest through such processes as forest fires, tree mortality from drought and heat and the release of carbon stocks in the soil represent dangers for the climate, the forest and the Brazilian population. Recent events indicate that deforestation can be controlled, given the political will, because the underlying processes depend on human decisions.
Descritores: Carbono
Efeito Estufa
Ecossistema Amazônico
Conservação dos Recursos Naturais
Biodiversidade
Fenômenos Ecológicos e Ambientais
Aquecimento Global
Ciclo Hidrológico
Responsável: BR6.1 - BCS - Biblioteca de Ciências da Saúde


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Id: lil-504705
Autor: Chig, Léo Adriano; Couto, Eduardo Guimarães; Novaes Filho, João Paulo; Rodrigues, Luiz Carlos Mattos; Johnson, Mark S; Weber, Oscarlina Lúcia dos Santos.
Título: Distribuição espacial da granulometria, cor e carbono orgânico do solo ao longo de um transecto em microbacias na Amazônia meridional / Spatial distribution of soil texture, color and soil organic carbon across a headwater transect in the southern Amazon
Fonte: Acta amaz;38(4):715-722, dez. 2008. ilus, tab.
Idioma: pt.
Resumo: O objetivo deste estudo foi determinar, em nível de detalhe, a distribuição e a variabilidade espacial da argila, do índice de avermelhamento e do carbono orgânico do solo, ao longo de transecto que cruza classes pedológicas distintas dentro de quatro microbacias, sob floresta tropical em Juruena (MT). Para isso, foram selecionados 34 pontos e coletadas amostras de solo nas profundidades de 0 a 20 cm e 40 a 60 cm. Os dados foram analisados por estatística descritiva e geoestatística. As maiores variabilidades espaciais ocorreram dentro da classe do Latossolo Vermelho-Amarelo Distrófico. Estes ocorrem nas elevações superiores a 280 m, enquanto os Plintossolos e Argissolos (com caráter plíntico) têm ocorrência restrita às áreas com altimetrias menores. Ao longo do transecto há maior variabilidade nos atributos índice de avermelhamento e argila; as áreas com piores condições de drenagens apresentaram menor variação espacial e menores índice de avermelhamento, isto é, maior homogeneidade da cor dos horizontes diagnósticos.

The study was conducted in forested headwater catchments near Juruena, Mato Grosso with the objective of determining the spatial distribution of soil physical characteristics including clay content, redness ratio, and soil organic carbon along a transect that encompassed distinct soil classes. Soil samples from 0-20 cm and 40-60 cm depths were collected from 34 points. Variables were analyzed using descriptive statistics and geostatistics. The parameters analyzed by ordinary kriging demonstrated that the highest spatial variability occurred within the soil class Typic Kandiustox. In the study area, Plinthustults and Ultisols (with plinthic characteristics) were only found to occur in landscape positions less than 280 m above sea level; Oxisols were found exclusively above 280 m.a.s.l. The redness ratio and clay content were the soil parameters with the highest spatial variability across the transect. Poorly drained areas (demonstrated by lower values of redness ratio) demonstrated the lowest degree of spatial variability, and correspondingly, the highest consistency of color within the diagnostic horizons.
Descritores: Solo
Carbono
Ecossistema Amazônico
Responsável: BR6.1 - BCS - Biblioteca de Ciências da Saúde


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Id: lil-515758
Autor: Amorim, Marcelo Andrade; Moreira-Turcq, Patrícia Florio; Turcq, Bruno Jean; Cordeiro, Renato Campello.
Título: Origem e dinâmica da deposição dos sedimentos superficiais na Várzea do Lago Grande de Curuai, Pará, Brasil / Source and deposition dynamics of superficial sediments in the "Várzea do Lago Grande de Curuai" floodplain, Pará, Brazil
Fonte: Acta amaz;39(1):165-171, mar. 2009. graf, mapas, tab, ilus.
Idioma: pt.
Resumo: Este estudo tem por objetivo caracterizar os sedimentos superficiais de um sistema de Várzea do Rio Amazonas, quanto a sua granulometria e ao seu teor orgânico, assim como compreender a origem e a hidrodinâmica destes sedimentos. 51 amostras de sedimento superficial foram coletadas na Várzea do Lago Grande de Curuai, localizada na margem direita do Rio Amazonas à aproximadamente 850km da foz. A granulometria, o teor em carbono orgânico e nitrogênio total, a razão entre o carbono e o nitrogênio (C/N), assim como o isótopo estável do carbono (δ13C) e do nitrogênio (δ15N) foram utilisados para este fim. Este estudo colocou em evidência que os sedimentos da várzea são finos, caracterizados principalmente pela presença de silte (médio à fino), seguido de argila e tem como principal fonte o Rio Amazonas e a Formação Alter do Chão. A presença de areia é pequena e extremamente localizada, próxima as áreas de deságue dos igarapés de terra firme que representam sua maior fonte. O teor de matéria orgânica nestes sedimentos varia entre 1,5 à 37% de carbono. Os resultados do isótopo do carbono (13C) e da razão C/N evidenciam a presença de matéria orgânica composta por diferentes fontes: material orgânico terrígeno, macrofítico, solos, material orgânico transportado pelo rio, e um componente fitoplanctônico.

The main objectives of this study were to characterize superficial sediments of an Amazonian floodplain system, by its size and organic content, and also to understand the local hydrodynamic and sources of these sediments. 51 samples of superficial sediment were collected in the floodplain “Várzea do Lago Grande de Curuai”, located on the right bank of the Amazon River, approximately, 850km from the estuary. The granulometry, the organic carbon and total nitrogen contents, the carbon and nitrogen ratio (C/N), as well as the isotope of carbon (δ13C) and nitrogen (δ15N) were used. This study points out that the sediments of the Curuai floodplain are fine, characterized mainly by the presence of silt (medium to fine), followed by clays. The main sources of these sediments are the Amazon River followed by “Alter do Chão” formation. The presence of sand was extremely located and near the inflow areas of “terra firme” igarapés that are the main source. The organic matter contents ranged between 1.5% and 37% of carbon. On the other hand, the results of 13C and C/N ratio evidence the presence of an organic matter made up of different sources: flooding forest, macrofítes, soil, organic material carried by the River and a phytoplanctonic component.
Descritores: Carbono
Matéria Orgânica
Hidrodinâmica
Responsável: BR6.1 - BCS - Biblioteca de Ciências da Saúde


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Id: biblio-903128
Autor: Toro-Cataño, Dubán A; Ramírez-García, Jairo; Sepúlveda-Mejía, Diego L.
Título: Riesgos ambientales y de seguridad en calderas a carbón de las pequeñas y medianas empresas «PYME¼, ubicadas en el municipio de Itagüí, Antioquia / Safety and environmental risks of coal fired boilers in small and medium-sized enterprises «SMEs¼, located in Itagüí town, Antioquia
Fonte: Rev. salud pública;19(4):437-445, jul.-ago. 2017. tab, graf.
Idioma: es.
Resumo: RESUMEN Objetivo Caracterizar los riesgos ambientales y de seguridad presentes en calderas con combustible de carbón de las pequeñas y medianas empresas, ubicadas en el municipio de Itagüí. Método Estudio descriptivo transversal: Se seleccionó una muestra a conveniencia de ocho calderas y sus operadores. La caracterización de las calderas se realizó por medio de la aplicación de cuatro instrumentos para evaluar y valorar los riesgos de seguridad, el nivel de seguridad, los riesgos ambientales y los impactos ambientales. Resultados El resultado del riesgo de seguridad mostró que el 62 % de las calderas presentó un nivel de riesgo no aceptable. El resultado del nivel de seguridad presentó que el 62 % de las calderas obtuvieron una valoración deficiente. El resultado del riesgo ambiental indicó que el 100 % de las calderas presentó un nivel de riesgo alto de afectación al entorno ambiental y un nivel de riesgo medio de afectación a los operadores. Con respecto a la valoración del impacto ambiental se observó que el 100 % de las calderas en estudio presentaban afectación de significancia alta sobre el componente aire, y afectación de significancia media sobre los componentes agua y suelo. Conclusiones Debido al bajo nivel de seguridad y al alto nivel de riesgo ambiental encontrado en las calderas estudiadas, las PYME deben conocer los riesgos existentes con el fin de disminuir la prevalencia de afectación de la salud de los calderistas e impactos al medio ambiente. Así mismo, implementar medidas de gestión encaminadas a la prevención y control de los riesgos caracterizados.(AU)

ABSTRACT Objective To describe the environmental and safety risks present in coal fired boilers in small and medium-sized enterprises, located in Itagüí town. Method Cross sectional descriptive study: An appropriate sample of 8 boilers with its corresponding operators was selected. The description of the boilers was carried out through the implementation of four instruments to evaluate and assess security risks; Its level of safety, the environmental risks and the environmental impacts. Results The security risk outcome showed that 62 % of the boilers presented an unacceptable level of risk. The safety level outcome showed that 62 % of boilers obtained a poor rating. The environmental risk outcome indicated that 100 % of the boilers had a high level of environmental impact and a medium level of impact for operators. Regarding the environmental impact assessment, 100 % of the boilers under study showed a high level of impact on the air component and medium level of impact on water and soil components. Conclusions Due to the low level of safety and the high level of environmental risk found in the boilers under study; SMEs should be aware of the current risks in order to reduce the exposure of the operators to health danger and the environme tal impacts as well. Moreover, it is needed to implement management measures aimed to prevent and control the risks described.(AU)
Descritores: Carbono/efeitos adversos
Exposição Ambiental/prevenção & controle
Segurança de Equipamentos
Pressão de Vapor
-Epidemiologia Descritiva
Estudos Transversais
Colômbia
Responsável: BR1.1 - BIREME


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Id: biblio-886795
Autor: XU, CHUNPING; YU, JINWEI; ZHAO, SHANSHAN; WU, SHUNGSHUNG; HE, PEIXIN; JIA, XUEWEI; LIU, YANQI; MAO, DUOBIN.
Título: Effect of carbon source on production, characterization and bioactivity of exopolysaccharide produced by Phellinus vaninii Ljup
Fonte: An. acad. bras. ciênc;89(3,supl):2033-2041, 2017. tab, graf.
Idioma: en.
Projeto: National Science Foundation of China.
Resumo: ABSTRACT The effect on different three carbon source (i.e. glucose, fructose and sucrose) on production, chemical characterization and antioxidant activity of exopolysaccharide (EPS) produced by Phellinus vaninii Ljup was investigated in this study. Amongst carbon sources examined, glucose and sucrose were favorable for the mycelia growth, while the maximum EPS yield was achieved when sucrose was employed. The predominant carbohydrate compositions in EPSs identified were gluconic acid, glucose, mannose and galactose acid. Then, FT-IR spectral analysis revealed prominent characteristic groups in EPSs. EPSs molecule exist as nearly globular shape form in aqueous solution. The variation also affects antioxidant activities by investigated by using hydroxyl and DPPH radical scavenging assay. Sucrose was best carbon source from the viewpoint of antioxidant activity due to the relatively high contents of galactose in the EPS with moderate molecular weight and polydispersity.
Descritores: Polissacarídeos Bacterianos/metabolismo
Carbono/metabolismo
Polissacarídeos Fúngicos
-Sacarose/metabolismo
Espectroscopia de Infravermelho com Transformada de Fourier
Frutose/metabolismo
Glucose/metabolismo
Responsável: BR1.1 - BIREME


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Id: biblio-886715
Autor: ESTRADA, GUSTAVO C D; SOARES, MÁRIO L G.
Título: Global patterns of aboveground carbon stock and sequestration in mangroves
Fonte: An. acad. bras. ciênc;89(2):973-989, Apr.-June 2017. tab, graf.
Idioma: en.
Projeto: INCT AmbTropic - Brazilian National Institute of Science and Technology for Tropical Marine Environments, CNPq/FAPESB.
Resumo: ABSTRACT In order to contribute to understand the factors that control the provisioning of the ecosystem service of carbon storage by mangroves, data on carbon stock and sequestration in the aboveground biomass (AGB) from 73 articles were averaged and tested for the dependence on latitude, climatic parameters, physiographic types and age. Global means of carbon stock (78.0 ± 64.5 tC.ha-1) and sequestration (2.9 ± 2.2 tC.ha-1.yr-1) showed that mangroves are among the forest ecosystems with greater capacity of carbon storage in AGB per area. On the global scale, carbon stock increases toward the equator (R²=0.22) and is dependent on 13 climatic parameters, which can be integrated in the following predictive equation: Carbon Stock in AGB = -16.342 + (8.341 x Isothermality) + (0.021 x Annual Precipitation) [R²=0.34; p < 0.05]. It was shown that almost 70% of carbon stock variability is explained by age. Carbon stock and sequestration also vary according to physiographic types, indicating the importance of hydroperiod and edaphic parameters to the local variability of carbon stock. By demonstrating the contribution of local and regional-global factors to carbon stock, this study provides information to the forecast of the effects of future climate changes and local anthropogenic forcings on this ecosystem service.
Descritores: Carbono/análise
Carbono/química
Áreas Alagadas
Sequestro de Carbono
-Valores de Referência
Clima Tropical
Análise de Regressão
Análise de Variância
Biomassa
Tipo de Publ: Revisão
Responsável: BR1.1 - BIREME


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Id: biblio-886727
Autor: SANTOS, DANIEL M C; ESTRADA, GUSTAVO C D; FERNANDEZ, VIVIANE; ESTEVAM, MARCIEL R M; SOUZA, BRUNNA T DE; SOARES, MÁRIO L G.
Título: First Assessment of Carbon Stock in the Belowground Biomass of Brazilian Mangroves
Fonte: An. acad. bras. ciênc;89(3):1579-1589, July-Sept. 2017. tab, graf.
Idioma: en.
Resumo: ABSTRACT Studies on belowground roots biomass have increasingly reported the importance of the contribution of this compartment in carbon stock maintenance in mangrove forests. To date, there are no estimates of this contribution in Brazilian mangrove forests, although the country has the second largest area of mangroves worldwide. For this study, trenches dug in fringing forests in Guaratiba State Biological Reserve (Rio de Janeiro, Brazil) were used to evaluate the contribution of the different classes of roots and the vertical stratification of carbon stock. The total carbon stock average in belowground roots biomass in these forests was 104.41 ± 20.73 tC.ha−1. From that, an average of 84.13 ± 21.34 tC.ha−1 corresponded to the carbon stock only in fine roots, which have diameters smaller than 5 mm and are responsible for over 80% of the total belowground biomass. Most of the belowground carbon stock is concentrated in the first 40 cm below the surface (about 70%). The root:shoot ratio in this study is 1.14. These estimates demonstrate that the belowground roots biomass significantly contributes, more than 50%, to the carbon stock in mangrove forests. And the mangrove root biomass can be greater than that of other Brazilian ecosystems.
Descritores: Solo/química
Carbono/análise
Áreas Alagadas
-Brasil
Biomassa
Responsável: BR1.1 - BIREME


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Id: biblio-886729
Autor: JAQUETTI, ROBERTO K; GONÇALVES, JOSÉ FRANCISCO C.
Título: Carbon and nutrient stocks of three Fabaceae trees used for forest restoration and subjected to fertilization in Amazonia
Fonte: An. acad. bras. ciênc;89(3):1761-1771, July-Sept. 2017. tab, graf.
Idioma: en.
Resumo: ABSTRACT Amazonia is crucial to global carbon cycle. Deforestation continues to be one of the main causes of the release of C into the atmosphere, but forest restoration plantations can reverse this scenario. However, there is still diffuse information about the C and nutrient stocks in the vegetation biomass. We investigated the carbon and nutrient stocks of Fabaceae trees (Inga edulis, Schizolobium amazonicum and Dipteryx odorata) subjected to fertilization treatments (T1 - no fertilization; T2 - chemical; T3 - organic; and T4 - organic and chemical fertilization) in a degraded area of the Balbina Hydroelectric Dam, AM - Brazil. As an early successional species, I. edulis stocked more C and nutrients than the other two species independent of the fertilization treatment, and S. amazonicum stocked more C than D. odorata under T1 and T4. The mixed species plantation had the potential to stock 4.1 Mg C ha-1 year-1, while I. edulis alone could stock 9.4 Mg C ha-1 year-1. Mixing species that rapidly assimilate C and are of significant ecological and commercial value (e.g., Fabaceae trees) represents a good way to restore degraded areas. Our results suggest that the tested species be used for forest restoration in Amazonia.
Descritores: Reguladores de Crescimento de Planta/farmacologia
Carbono/análise
Florestas
Conservação dos Recursos Naturais
Fabaceae/classificação
Fabaceae/efeitos dos fármacos
-Solo
Brasil
Biomassa
Fabaceae/química
Responsável: BR1.1 - BIREME


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Id: lil-781397
Autor: Medeiros, J C C; Coelho, F F; Teixeira, E.
Título: Biomass allocation and nutrients balance related to the concentration of Nitrogen and Phosphorus in Salvinia auriculata (Salviniaceae) / Alocação de biomassa e o Balanço de nutrientes relacionados à concentração de Nitrogênio e Fósforo em Salvinia auriculata (Salviniaceae)
Fonte: Braz. j. biol;76(2):461-468, Apr.-June 2016. tab, graf.
Idioma: en.
Resumo: Abstract Aquatic plants can use differential allocation (trade-off) of carbon among their structures depending on the nutrition concentration. Given that N and P are limiting in the growth of plants, our questions were: Are the N and P concentrations in S. auriculata related to the biomass allocation to its structures? Is a differential allocation of N and P between floating and submerged leaves? We evaluated the relation between the nutrients and the biomass allocation, and the trade-off among the leaves using the Spearman correlation. Our results showed that N and P concentrations in S. auriculata are related to the biomass allocation to its structures, and that there is no trade-off of these nutrients between “shoot and root”. Thus, we can see the importance of N and P concentration in the biomass of S. auriculata, and why this plant is capable to development in different environments as a weedy.

Resumo Plantas aquáticas podem realizar alocação diferencial (trade-off) de carbono entre as suas estruturas dependo da disponibilidade de nutrientes. Considerando que N e P são limitantes para o crescimento de plantas, nossas perguntas foram: As concentrações de N e P em S. auriculata estão relacionadas com a alocação de biomassa para suas estruturas? Existe alocação diferencial de N e P entre os folíolos aéreos e a “raiz”? Avaliamos a relação entre os nutrientes e a biomassa, e o trade-off entre as folhas utilizando correlação de Spearman. Os resultados encontrados mostram que as concentrações de N e P em S. auriculata estão relacionadas com a alocação de biomassa para as suas estruturas, e que não há um trade-off de N e P entre os folíolos aéreos e a “raiz”. Dessa maneira, é possível observar a importância de N e P no ganho de biomassa de S. auriculata, e porque a espécie é capaz de se desenvolver em diferentes ambientes como uma planta daninha.
Descritores: Fósforo/análise
Fósforo/metabolismo
Fenômenos Fisiológicos Vegetais
Plantas Daninhas/fisiologia
Nitrogênio/análise
Nitrogênio/metabolismo
-Carbono/metabolismo
Estatística como Assunto
Folhas de Planta/crescimento & desenvolvimento
Biomassa
Hidrobiologia/métodos
Responsável: BR1.1 - BIREME


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Id: biblio-886880
Autor: VIEIRA, CRISTIANE R; WEBER, OSCARLINA L S; SCARAMUZZA, JOSÉ FERNANDO.
Título: Ash content, carbon and C/N ratio in paricá in function of NPK fertilization
Fonte: An. acad. bras. ciênc;90(1):333-341, Mar. 2018. tab.
Idioma: en.
Resumo: ABSTRACT Fertilization in areas of forest plantations is needed to supplement plants´ nutritional needs until harvest. An experiment was performed to check the influence of fertilization on levels of ash, carbon and C/N relation in Schizolobium amazonicum. Soil liming was performed and fertilization occurred after 15 days of incubation. S. amazonicum seedlings were produced and submitted to fertilization with N, P and K: N = 0, 40, 80 and 120 kg ha-1; P2O5 = 0, 50, 100 and 200 kg ha-1; K2O = 0, 50, 100 and 200 kg ha-1. The plants were measured after 180 days. The seedlings of 20 treatments with the highest increase in height and diameter were transplanted to the field. Soil was fertilized and limestone was spread; seedlings were distributed into randomized blocks, with six replications. After 12 months, the plants were removed to determine ash, organic carbon, C/N relation contents. The ashes were submitted to digestion to determine nutrient concentrations. Fertilization influenced the levels of ash and organic carbon and C/N relation in S. amazonicum. Results indicate that the species has a potential for energy production.
Descritores: Solo/química
Carbono/análise
Fertilizantes
Cinza de Carvão/análise
Fabaceae/efeitos dos fármacos
Fabaceae/química
Nitrogênio/análise
-Fósforo/química
Potássio/química
Valores de Referência
Fatores de Tempo
Carbono/química
Florestas
Reprodutibilidade dos Testes
Cinza de Carvão/química
Fabaceae/fisiologia
Nitrogênio/química
Responsável: BR1.1 - BIREME



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