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Id: biblio-1047771
Autor: Yan, Xia; Qian, Chaoju; Yin, Xiaoyue; Fan, Xingke; Zhao, Xueyong; Gu, Menghe; Wang, Tao; Ma, Xiao-Fei.
Título: A whole-transcriptome approach to evaluate reference genes for quantitative diurnal gene expression studies under natural field conditions in Tamarix ramosissima leaves
Fonte: Electron. j. biotechnol;35:48-56, sept. 2018. tab, graf.
Idioma: en.
Projeto: National Key Research and Development Program of China; . Natural Science Foundation of China; . Gansu Science and Technology Supporting Project.
Resumo: Background: Tamarix ramosissima is a desert forest tree species that is widely distributed in the drought-stricken areas to sustain the fragile ecosystem. Owing to its wide usage in the desert restoration of Asia, it can be used as an ecophysiological model plant. To obtain reliable and accurate results, a set of reference genes should be screened before gene expression. However, up to date, systematical evaluation of reference genes has not been conducted in T. ramosissima. Results: In this study, we used eigenvalues derived from principal component analysis to identify stable expressed genes from 72,035 unigenes from diurnal transcriptomes under natural field conditions. With combined criteria of read counts above 900 and CV of FPKM below 0.3, a total of 7385 unigenes could be qualified as candidate reference genes in T. ramosissima. By using three statistical algorithm packages, geNorm, NormFinder, and BestKeeper, the stabilities of these novel reference genes were further compared with a panel of traditional reference genes. The expression patterns of three aquaporins (AQPs) suggested that at least UBQ (high expression), EIF4A2 (low expression), and GAPDH (moderate expression) could be qualified as ideal reference genes in both RT-PCR and RNA-seq analysis of T. ramosissima. Conclusions: This work will not only facilitate future studies on gene expression and functional analysis of genetic resources of desert plants but also improve our understanding of the molecular regulation of water transport in this plant, which could provide a new clue to further investigate the drought adaptation mechanism of desert plant species under harsh environments.
Descritores: Tamaricaceae/genética
Transcriptoma
-Padrões de Referência
Adaptação Biológica
Expressão Gênica
Ecossistema
Folhas de Planta/genética
Deserto
Recuperação e Remediação Ambiental
Secas
Reação em Cadeia da Polimerase em Tempo Real
RNA-Seq
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1025493
Autor: Dávila-Recinos, Gabriela; Ortíz-Aldana, José R; Reyes-Morales, Fátima.
Título: Efecto del microhábitat sobre la abundancia y riqueza específica de los macroinvertebrados bentónicos en dos ríos tropicales de montaña, Guatemala / Effect of microhabitat on the abundance and specific richness of benthic macroinvertebrates in two tropical mountain streams, Guatemala
Fonte: Cienc. tecnol. salud;6(1):7-21, 2019. ilus.
Idioma: es.
Resumo: Los macroinvertebrados bentónicos cumplen funciones ecológicas importantes en los sistemas lóticos, como el traspaso de energía a través de las redes tróficas, la descomposición de la materia orgánica, el reciclaje de nutrientes y la mezcla de sedimentos. Uno de los principales factores que definen la composición del ensamble de macroinvertebrados es la disponibilidad de microhábitats. Debido a ello, se evaluó el efecto de ocho microhábitats (hojarasca, grava, piedras, roca, musgo, vegetación acuática, pozas y cataratas), así como de la velocidad y profundidad, sobre la abundancia y riqueza específica de los macroinvertebrados en los ríos La Labor y Tzununá en la cuenca del lago Atitlán en el altiplano de Guatemala. Se colectaron 19,529 organismos correspondientes a 91 taxa, 49 familias y 65 géneros. El microhábitat que presentó mayor abundancia fue hojarasca (7,723 organismos) y pozas presentó la menor (652 organismos). En cuanto a riqueza, piedras presentó la mayor riqueza (41 taxa) y musgo tuvo la menor (28 taxa). Se evidenció que el microhábitat tuvo un efecto significativo sobre la abundancia y la riqueza (p < .05), ésta última también se vio influenciada por la profundidad (p = .030). Se concluyó que el microhábitat es un factor importante, para determinar la composición de la comunidad de macroinvertebrados; ya que la presencia y dominancia de elementos de heterogeneidad en los ríos, contribuye a incrementar la diversidad del hábitat físico, así como las opciones de alimento y refugio, promoviendo la abundancia y riqueza de macroinvertebrados en los sistemas lóticos.

Benthic macroinvertebrates serve important ecological functions in lotic systems, such as the transfer of energy through trophic networks, decomposition of organic matter, nutrient recycling and sediment mixing. One of the main factors that define the composition of the macroinvertebrate assemblage is the availability of microhabitats. The survey evaluated the effect of eight microhabitats (leaf litter, gravel, stones or pebbles, rock, moss, aquatic vegetation, pools and waterfalls), as well as speed and depth, on the abundance and specific richness due to rarefaction of the macroinvertebrates in La Labor and Tzununá rivers, which are part of the Lake Atitlán basin in the Guatemalan highlands. In this area 19,529 organisms corresponding to 91 taxa, 49 families and 65 genera were collected. The highest abundance was in leaf litter microhabitat (7,723 organisms), while stones showed the highest richness (41 taxa). Pools had the lowest abundance (652 organisms) and moss had the lowest richness (28 taxa). The microhabitat has a significant effect on abundance and richness (p < .05), also depth has a significant effect on richness (p = .030). The microhabitat is an important factor, to determine the composition of the macroinvertebrate community, because the presence and dominance of elements of heterogeneity in the rivers contributes to increase the diversity of the physical habitat, which provides refuge and food that satisfy the requirements of organisms promoting the abundance and richness of macroinvertebrates in lotic systems.
Descritores: Bacias Hidrográficas/classificação
Fauna Bentônica
-Seixos
Sedimentos
Ecossistema
Rios
Recuperação e Remediação Ambiental
Limites: Animais
Responsável: GT49.1


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Id: biblio-987196
Autor: Martínez Arévalo, José Vicente.
Título: Modelo de negocio de restauración productiva de Abies guatemalensis Rehder utilizando plantas nodrizas para su establecimiento / Business model of productive restoration of Abies guatemalensis Rehder using nurse plants for its establishment
Fonte: Cienc. tecnol. salud;5(2):182-188, 2018. ilus.
Idioma: es.
Resumo: El presente reporte de caso tuvo como objetivo generar el modelo de negocios para el pinabete (Abies guatemalensis Rehder) en restauración, no se pretende hacer un análisis profundo de la producción de árboles de pinabete, únicamente mostrar que la producción se puede combinar con la conservación. En la región alta del altiplano occidental de Guatemala hay muchas tierras degradadas fuera de bosques, donde la sucesión vegetal ha promovido el crecimiento de especies arbustivas, útiles como nodrizas en el establecimiento de pinabete para protegerlas de heladas y lograr establecimiento mayor a 80 %, lo cual ya se ha puesto en práctica por varios silvicultores locales. Se realizó un análisis técnico financiero sobre la producción de pinabete con doble propósito: especie comercial y para la restauración de áreas degradadas. El modelo de negocios se estableció para 0.25 ha, con un precio de venta por árbol de Q. 300, con y sin incentivos forestales, considerando establecer previamente plantas arbustivas. Los resultados indican que con una inversión de Q. 45,227 durante ocho años a una tasa de descuento del 13 %, el Valor Actual Neto (VAN) toma valores entre Q. 398,576 a 742,020 con una Tasa Interna de Rendimiento (TIR) entre 30 y 50 %. A la vez se preparó un plan de negocios utilizando la metodología Canvas, que establece un plan estratégico que permite visualizar lo que actualmente se está realizando y qué situaciones hay que mejorar. El modelo propuesto puede utilizarse de una forma mixta para la conservación al dejar al menos un 30 % de los árboles, la otra parte se puede utilizar para comercialización a partir del octavo al 12do año de forma sostenible.

The present case study aimed to generate the business model for the Guatemalan fir (Abies guatemalensis Rehder) under restoration process. In the highlands of the altiplano region in western Guatemala there are many degraded lands outside of forests, where the ecological succession has promoted the growth of shrub species that help to the establishment of the fir and to protect it from frost. This condition also helped the specie to achieve more than 80 % of survival rate. The method has been implemented by several local silvicultors. A technical and financial analysis was carried out on the production of fir with two objectives: production of commercial Christmas trees and for the restoration of degraded areas. The business model was established for an area of 0.25 ha, with an estimated market price per tree of Q. 300, with and without forestry incentives, assuming previously establish shrub plants. The results indicate that with an investment of Q. 45,227 for eight years at a discount rate of 13 %, the Net Present Value (NPV) takes values between Q. 398,576 to 742,020 with an Internal Rate of Return (IRR) ranging between 30 and 50 %. At the same time, a business plan was prepared using the Canvas methodology, which establishes a strategic plan that allows visualizing what is currently being done and what areas need improvement. The proposed model can be used in a mixed way for conservation by leaving at least 30 % of the trees; the other part can be used for trading the trees from the eighth to the twelfth years old in a sustainable way.
Descritores: Abies
Recuperação e Remediação Ambiental
-Árvores/crescimento & desenvolvimento
Agricultura Florestal/economia
Espécies em Perigo de Extinção/tendências
Responsável: GT49.1


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Id: biblio-868824
Autor: Martínez-Arévalo, José V.
Título: Los bosques de Abies guatemalensis Rehder de San Marcos, Guatemala: una oportunidad para su restauración ecológica / The forests of Abies guatemalensis Rehder of San Marcos, Guatemala: an opportunity for ecological restoration
Fonte: Cienc. tecnol. salud;3(1):27-46, ene.-jun. 2016. ilus, tab.
Idioma: es.
Resumo: El pinabete, Abies guatemalensis Rehder, es una especie distribuida en las montañas altas de Guatemala. Según elConsejo Nacional de Áreas Protegidas (Conap), sus poblaciones se encuentran severamente fragmentadas. Porsu rareza y fragmentación, esta especie se encuentra protegida por el Convenio sobre el Comercio Internacional deEspecies Amenazadas de Fauna y Flora Silvestre (Cites), lo que pone en relieve la importancia de la recuperaciónde sus bosques para su debida conservación. El éxito de su establecimiento puede mejorase al sembrarla junto a plantas nodriza, que le ayudarían a sobrevivir a las condiciones secas del año y las heladas que se presentan en las zonas de mayor altitud del país durante los meses de noviembre a febrero. Este trabajo muestra las características físicas, químicas y de vegetación del área de tres bosques de pinabete (A. guatemalensis) de la parte alta de San Marcos. Además, presenta la propuesta de restauración ecológica estimulada simulando la sucesión vegetal del área. Se elaboraron mapas, y describieron tres bosques de pinabete y sus alrededores; se presenta el estudio de la composición química del suelo y la vegetación y su representación en diferentes etapas de sucesión vegetal. Además, se propone la recuperación de áreas alrededor de parches de bosque, consistente en establecer plantas arbustivas en lugares abiertos donde aún no hay; por su parte en aquellas áreas donde ya se encuentren arbustos, se propone utilizarlos como plantas nodriza para establecer árboles de varias especies buscando mantener biodiversidad deespecies arbóreas, en donde la teoría de la sucesión indica que el pinabete va a dominar al final. Esta propuesta hademostrado viabilidad porque es una práctica conocida fuera de bosques naturales en áreas de San Marcos paraestablecer el pinabete con fines comerciales, que aprovecha la sucesión vegetal natural del área.

The fir, Abies guatemalensis Rehder, is distributed in the highlands of Guatemala. According to the NationalProtected Areas Council (Conap), their populations are severely fragmented. For its rarity and fragmentation,it is protected by the Convention on International Trade in Endangered Species of Wild Fauna and Flora species(Cites), indicating the importance of the recovery of their forests for the proper conservation of the species. Thesuccess of his establishment may be enhanced to sow with nurse plants, which would help to survive the dryconditions of the year and frosts that occur in the higher elevations of the country during the months of Novemberto February. This work shows the features physical and chemical and vegetation in the area of three forests of fir (A. guatemalensis) of the top of San Marcos. In addition, the proposal of ecological restoration simulating plantsuccession in the area. Maps were drawn, and three fir forests and surrounding described; it is shown the study the chemical composition of soil and vegetation and their representation in different ages of plant succession. Further, it is proposed the recovery of areas around patches of forest, consting of which is establish shrubby plants in open spaces where there are not yet; in areas where bushes already are, it is proposed to use it as nurse plants to establish trees of various species seeking to maintain biodiversity of tree species, where the theory of succession indicates that the fir will dominate in the end. This proposal is feasible because as it is known outside natural forests inareas of San Marcos to establish the fir for commercial purposes, which uses the natural plant succession the area.
Descritores: Biodegradação Ambiental
Conservação dos Recursos Naturais
Florestas
Recuperação e Remediação Ambiental
Limites: Humanos
Responsável: GT49.1


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Id: biblio-1132185
Autor: Castro, Luiz Eduardo Nochi de; Meurer, Eduardo César; Alves, Helton José; Santos, Marco Aurélio Reis dos; Vasques, Erika de Castro; Colpini, Leda Maria Saragiotto.
Título: Photocatalytic Degradation of Textile dye Orange-122 Via Electrospray Mass Spectrometry
Fonte: Braz. arch. biol. technol;63:e20180573, 2020. tab, graf.
Idioma: en.
Resumo: Abstract This work reports the study of the potential application of Zn/TiO2 catalysts, obtained by the sol-gel method, in processes of environmental decontamination through the reactions of photodegradation of textile dye, followed by electrospray mass spectrometry. The catalysts synthesis was performed according to a 2² factorial design with repetition at the central point. The characterization techniques used were: N2 adsorption measurements (BET method), scanning electron microscopy with energy dispersive X-ray (MEV/EDS), X-ray diffraction and point of zero charge (PZC). The photocatalytic tests were performed in batch in the presence of sunlight, and to evaluate the degradation kinetics study, a rapid direct injection electrospray mass spectrometry (DI-ESI-MS) method has been developed. By the photocatalytic tests, the calcination temperature of 400 °C has shown the best results of discoloration for the reactive Orange-122 dye (99.76%) in a reaction time of 2h. The discoloration kinetics were a pseudo-first order, and a statistical analysis was performed to investigate the effects of the variables and to optimize the conditions of discoloration to the dye. After the reactional time of 2 h, an ion of m/z 441.5 was detected by ESI-MS, indicating that the photocatalytic process was effective for the degradation of the dye to secondary compounds.
Descritores: Compostos Azo/toxicidade
Biodegradação Ambiental
Descontaminação/métodos
Espectrometria de Massas em Tandem/métodos
Recuperação e Remediação Ambiental/métodos
Águas Residuárias
-Fotoquímica
Têxteis/toxicidade
Microscopia Eletrônica de Varredura
Catálise
Domínio Catalítico
Espectrometria de Massas por Ionização por Electrospray
Corantes
Fotobiorreatores
Modelos Teóricos
Responsável: BR1.1 - BIREME


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Id: lil-783575 LILACS-Express
Autor: López Vargas, Luis Eduardo; Becoche Mosquera, Jorge Mario; Macías Pinto, Diego Jesús; Ruiz Montoya, Katherinn; Velasco Reyes, Alejandra; Pineda, Soallin.
Título: ESTRUCTURA Y COMPOSICIÓN FLORÍSTICA DE LA RESERVA FORESTAL - INSTITUCIÓN EDUCATIVA CAJETE, POPAYÁN (CAUCA) / FLORISTIC STRUCTURE AND COMPOSITION OF THE CAJETE EDUCATIONAL INSTITUTION FOREST RESERVE IN POPAYÁN (CAUCA)
Fonte: Rev. luna azul;(41):131-151, jul.-dic. 2015. ilus, tab.
Idioma: es.
Resumo: Se caracterizó la estructura y composición florística del remanente boscoso ubicado en la Reserva Forestal de la Institución Educativa Cajete, Popayán (Cauca). El inventario florístico se hizo mediante colecta libre realizada en el interior y la periferia del bosque. Se registraron en total 164 especies, 130 géneros y 58 familias. En Magnoliophyta se registraron 142 especies, 112 géneros y 44 familias; las familias más diversas fueron Asteraceae (31 especies y 26 géneros) y Araceae (10 especies y 3 géneros). En Lycophyta y Monylophyta se reconocieron 22 especies, 18 géneros y 14 familias; siendo Polypodiaceae con 4 especies la familia con mayor riqueza. Para determinar la estructura se muestrearon todos los individuos con DAP ≥ 1 cm en 10 bandas de 50 x 2 m, hallándose 560 individuos de plantas vasculares pertenecientes a 39 especies, 33 géneros y 25 familias. El bosque presentó 3 estratos: herbáceo, arbustivo y arbóreo. El estrato arbustivo fue el dominante con un elevado número de especies; el estrato arbóreo estuvo constituido por unas pocas especies. Quercus humboldtii y Banara guianensis fueron las especies con mayor dominancia e índice de valor de importancia en el bosque.

The floristic structure and composition of the remaining wooded area located in the Cajete Educational institution forest reserve in Popayan (Cauca) was studied. The floristic inventory was performed through free collection carried out inside and in the periphery of the forest. In total 164 species, 130 genera and 58 families were recorded. In Magnoliophyta 142 species belonging to 112 genera and 44 families were recorded, being Asteraceae (31 species and 26 genera) and Araceae (10 species and 3 genera) the most diverse families. In Monylophyta and Lycophyta 22 species belonging to 18 genera and 14 families were recognized, being Polypodiaceae with 4 species, the family with more richness. To determine the structure all individuals were sampled with ≥ 1 cm DAP in 10 bands of 50 x 2 m, and in total 560 individuals of vascular plants belonging to 39 species, 33 genera and 25 families were found. The forest presented three different strata: herbaceous, shrubby and arboreal. The shrubby stratum was dominant with a high number of species whereas the arboreal stratum consisted only of a few species. Quercus humboldtii and Banara guianensis were the species with greater dominance and with high importance value index in the forest.
Descritores: Recuperação e Remediação Ambiental
-Florestas
Agricultura Florestal
Microbiota
Limites: Humanos
Tipo de Publ: Artigo Clássico
Responsável: CO54.1 - Centro de Biblioteca e Información Científica


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Id: biblio-1181703
Autor: Perú. Ministerio de Salud. Dirección General de Salud Ambiental.
Título: Directiva sanitaria para la prevención y control de la leptospira en reservorios / Healthcare Directive for the prevention and control of leptospira reservoirs.
Fonte: Lima; Perú. Ministerio de Salud. Dirección General de Salud Ambiental; 2013. 18 p. ilus.
Idioma: es.
Resumo: La presente publicación establece los procesos técnicos y administrativos para realizar las intervenciones integrales de prevención y control del agente zoonótico en reservorios, así como de promover la participación de todos los actores involucrados en la prevención y control de la leptospirosis
Descritores: Leptospira
Leptospirose
Recuperação e Remediação Ambiental
Reservatórios de Água
Saúde Ambiental
-Peru
Tipo de Publ: Guia
Responsável: PE18.1 - Biblioteca Central
[{"text": "PE18.1", "_a": "MS/DIGESA 0074", "_b": "(Formato Digital)"}]


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Id: lil-574667
Autor: Barbosa, Antenor Pereira; Campos, Moacir Alberto Assis; Sampaio, Paulo de Tarso Barbosa; Nakamura, Shozo; Gonçalves, Cláudio de Queiroz Blair.
Título: O Crescimento de duas espécies florestais pioneiras, pau-de-balsa (Ochroma lagopus Sw.) e caroba (Jacaranda copaia D. Don), usadas para recuperação de áreas degradadas pela agricultura na Amazônia Central, Brasil / Growth of two forest pioneer species, pau-de-balsa (Ochroma lagopus Sw.) e caroba (Jacaranda copaia D. Don), used for rehabilitation of degraded areas from agriculture in Central Amazon, Brazil
Fonte: Acta amaz;33(3):447-482, 2003. tab.
Idioma: pt.
Resumo: O objetivo deste trabalho foi estudar o crescimento das espécies florestais pioneiras pau-de-balsa (Ochroma lagopus Sw.) e caroba (Jacaranda copaia D. Don) para a recuperação de áreas degradadas pela agricultura. Na área, situada no km 120 da BR-174, tinha sido plantado mandioca e banana e abandonada há 8 anos, formando uma capoeira de porte baixo e rala. O experimento foi instalado em maio/98, com e sem gradagem da área. O espaçamento foi de 3x3m, em covas de 20 cm (diâmetro) x 30 cm (profundidade), com adubação de 150g/cova de NPK (4-16-8) e calcário dolomítico na proporção de 3:1. Para a avaliação do crescimento, foram medidas a altura e o diâmetro das plantas aos 2 meses (julho/98) e a cada ano aproximadamente (junho/99, setembro/00 e maio/01). Os dados foram analisados através do delineamento inteiramente casualisado. A sobrevivência do pau-de-balsa foi maior em área gradeada (97,1 por cento) do que em area não gradeada (92,5 por cento), após o primeiro ano do plantio; da caroba, foi cerca de 90 por cento e sem diferenças entre as areas. A altura e diâmetro do pau-de-balsa, foram maiores em área gradeada, a partir do primeiro ano, chegando no terceiro ano a 11,85 m de altura e 11,42 cm de diâmetro. Na caroba, a diferença ocorreu a partir do segundo ano e no terceiro chegou a 8,37 m de altura e 11,18 cm de diâmetro. Além de outros fatores inerentes às espécies, o solo mais friável das áreas gradeadas, possibilitou um maior crescimento em altura e diâmetro das duas espécies estudadas.

The objective of experiment was study the growth of pioneer forest species pau-de-balsa (Ochroma lagopus) and caroba (Jacaranda copaia) to rehabilitate degraded areas from agriculture. The experiment carried out at Br-174, km 120. After the use for cassava and banana plantations the area was abandoned for 8 years. The secondary forest that took place was of low height and sparse trees. The experiment was installed at may/98 and composed by harrowed and no harrowed areas. The seedlings were planted in 3 x 3 m spacing, in 20 cm diameter by 30 cm deep holes, with 150g of fertilizer NPK (4-16-8) and dolomite limestone in the proportion 3:1. To evaluation the growth were measured the height and diameter in july/98 and each year, approximately (June/99, September/00 and May/01). The data were obtained from planted species comparing harrowed and no harrowed areas in a full random design. The survival of pau-de-balsa, was greater in harrowed area (97,1 percent) in relation to no harrowed area (92,5 percent) after one year of planting; and the survival of caroba, was 90 percent after one year of planting and showed no difference when compared the harrowed and no harrowed areas. The height and diameter of pau-de-balsa were greater in harrowed area after one year of planting, reaching 11.85 m and 11.42 cm, respectively. The differences occurred in caroba trees after the second year of planting, and reached, in the third year, 8.37 m of high and 11,18 cm in diameter. Besides other factors inherent to the species, the more friable soil of the harrowed area, facilitated higher growth to two studied species.
Descritores: Jacaranda caroba
Ecossistema Amazônico
Bombacaceae
Recuperação e Remediação Ambiental
Responsável: BR6.1 - BCS - Biblioteca de Ciências da Saúde


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Id: lil-448127
Autor: Silva, Carlos E. M; Gonçalves, José Francisco de C; Feldpausch, Ted R; Luizão, Flávio J; Morais, Ronaldo R; Ribeiro, Glaudecy O.
Título: Eficiência no uso dos nutrientes por espécies pioneiras crescidas em pastagens degradadas na Amazônia central / Nutrient use efficiency for pioneer species grown on abandoned pastures in central Amazonia
Fonte: Acta amaz;36(4):503-512, out.-dez. 2006. graf, tab.
Idioma: pt.
Resumo: Nas últimas décadas, considerável parcela da floresta amazônica tem sido transformada em pastagens que, em função da baixa fertilidade natural dos solos e do manejo deficiente, decrescem rapidamente em produtividade e são abandonadas, dando lugar a uma sucessão secundária arbórea adaptada à baixa disponibilidade de nutrientes. O objetivo deste estudo foi obter informações sobre a eficiência no uso dos nutrientes por espécies arbóreas freqüentes nesses ambientes degradados, após calagem e aplicação de fosfato. O experimento realizado numa área de sucessão secundária com seis anos de idade, consistiu na aplicação de quatro tratamentos: controle; aplicação de fósforo (P); aplicação de fósforo e calcário (P+Cal); e aplicação de fósforo, calcário e gesso (P+Cal+G). As determinações das taxas de fotossíntese, bem como as coletas de amostras de solo e de folhas foram realizadas oito meses após a aplicação dos tratamentos. A aplicação do corretivo e do fosfato favoreceu o desempenho das espécies nos tratamentos P+Cal e P+Cal+G. Bellucia grossularioides acumulou mais N, P e Zn, enquanto que Laetia procera acumulou mais Ca e Mn. Vismia japurensis foi a espécie mais eficiente no uso dos nutrientes, em função dos altos valores da taxa fotossintética; apresentou baixos teores foliares de P quando comparada com Bellucia grossularioides, sugerindo ser uma espécie bem adaptada a ambientes com baixa disponibilidade de nutrientes, como ocorre em áreas degradadas na Amazônia.

Large areas of Amazonian forest have been converted to pastures over the last two decades. Low soil fertility and mismanagement results in a rapid decline in net primary productivity leading the pastures to be abandoned, and woody vegetation adapted to low nutrient conditions colonize the areas. The objective of this study was to examine nutrient use efficiency, following liming (calcium) and phosphorus addition by three of the most frequent colonizing species. The experiment conducted on a six year-old secondary forest, consisted of four treatments: control; phosphorus addition (P); phosphorus and lime addition (P+Cal); and phosphorus, lime and gypsum addition (P+Cal+G). Leaf gas exchange, soil and leaf nutrient concentration were determined eight months after the treatment application. There was a significant response by species to the addition of phosphorus and lime (P+Cal and P+Cal+G). The species, Bellucia grossularioides accumulated more N, P and Zn in the leaves, while Laetia procera accumulated more Ca and Mn. The species Vismia japurensis had higher nutrient use efficiency, as a function of the higher photosynthetic rates. Vismia japurensis presented lower P concentrations than Bellucia grossularioides, suggesting that is well adapted to environments low in nutrients, as this species often occurs in degraded areas in Amazonia.
Descritores: Fósforo
Sulfato de Cálcio
Solos Calcários
Recuperação e Remediação Ambiental
Responsável: BR6.1 - BCS - Biblioteca de Ciências da Saúde


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Id: biblio-1003279
Autor: Hassan, Hamdy A; Dawah, Somya E; El-Sheekh, Mostafa M.
Título: Monitorización de la capacidad de degradación de las nuevas bacterias haloalcalifílicas resistentes a cloruro de tributiltina (TBTCl) en una ubicación contaminada por butiltina / Monitoring the degradation capability of novel haloalkaliphilic tributyltin chloride (TBTCl) resistant bacteria from butyltin-polluted site
Fonte: Rev. argent. microbiol;51(1):39-46, mar. 2019. ilus.
Idioma: en.
Resumo: Tributyltin (TBT) is recognized as a major environmental problem at a global scale. Haloalkaliphilic tributyltin (TBT)-degrading bacteria may be a key factor in the remediation of TBT polluted sites. In this work, three haloalkaliphilic bacteria strains were isolated from a TBT-contaminated site in the Mediterranean Sea. After analysis of the 16S rRNA gene sequences the isolates were identified as Sphingobium sp. HS1, Stenotrophomonas chelatiphaga HS2 and Rhizobium borbori HS5. The optimal growth conditions for biodegradation of TBT by the three strains were pH 9 and 7% (w/v) salt concentration. S. chelatiphaga HS2 was the most effective TBT degrader and has the ability to transform most TBT into dibutyltin and monobutyltin (DBT and MBT). A gene was amplified from strain HS2 and identified as TBTB-permease-like, that encodes an ArsB-permease. A reverse transcription polymerase chain reaction analysis in the HS2 strain confirmed that the TBTB-permease-like gene contributes to TBT resistance. The three novel haloalkaliphilic TBT degraders have never been reported previously.

Se considera a la tributiltina (TBT) como un problema medioambiental serio a escala global. Las bacterias haloalcalifílicas degradadoras de TBT pueden constituir un factor clave para remediar áreas contaminadas con dicho xenobiótico. En este estudio se aislaron 3 cepas de bacterias haloalcalifílicas procedentes de un sitio contaminado con TBT en el mar Mediterráneo. Tras analizar las secuencias del gen de 16S del ARNr, se identificaron los aislados como Sphingo-bium sp. HS1, Stenotrophomonas chelatiphaga HS2 y Rhizobium borbori HS5. Las condiciones de crecimiento óptimas para la biodegradación de TBT por parte de las 3 cepas fueron pH 9 y 7% (p/v) de concentración de sal. S. chelatiphaga HS2 fue el degradador de TBT más efectivo, con capacidad de transformar la mayor parte de ese compuesto en dibutiltina y monobutiltina (DBT y MBT). Se amplificó un gen de la cepa HS2, que fue identificado como tipo TBTB-permeasa, que codifica para una ArsB permeasa. Un análisis de la cepa HS2 por reacción en cadena de la polimerasa con transcriptasa inversa (RT PCR) confirmó que el gen TBTB-permeasa contribuye a la resistencia al TBT. Estos 3 nuevos degradadores haloalcalifílicos de TBT no habían sido reportados previamente.
Descritores: Bactérias/isolamento & purificação
Recuperação e Remediação Ambiental/métodos
-Biodegradação Ambiental
Mar Mediterrâneo/epidemiologia
Reação em Cadeia da Polimerase/métodos
Transcrição Reversa/genética
Recuperação e Remediação Ambiental/análise
Tipo de Publ: Estudo de Avaliação
Responsável: AR635.1 - FCVyS - Servicio de Información y Documentación



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