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1.
Rev. biol. trop ; 71(1)dic. 2023.
Article Dans Espagnol | SaludCR, LILACS | ID: biblio-1514965

Résumé

Introducción: La gran diversidad de especies maderables tropicales demanda el desarrollo de nuevas tecnologías de identificación con base en sus patrones o características anatómicas. La aplicación de redes neuronales convolucionales (CNN) para el reconocimiento de especies maderables tropicales se ha incrementado en los últimos años por sus resultados prometedores. Objetivo: Evaluamos la calidad de las imágenes macroscópicas con tres herramientas de corte para mejorar la visualización y distinción de las características anatómicas en el entrenamiento del modelo CNN. Métodos: Recolectamos las muestras entre el 2020 y 2021 en áreas de explotación forestal y aserraderos de Selva Central, Perú. Luego, las dimensionamos y, previo a la identificación botánica y anatómica, las cortamos en secciones transversales. Generamos una base de datos de imágenes macroscópicas de la sección transversal de la madera, a través del corte, con tres herramientas para ver su rendimiento en el laboratorio, campo y puesto de control. Resultados: Usamos tres herramientas de corte para obtener una alta calidad de imágenes transversales de la madera; obtuvimos 3 750 imágenes macroscópicas con un microscopio portátil que corresponden a 25 especies maderables. El cuchillo ''Tramontina'' es duradero, pero pierde el filo con facilidad y se necesita una herramienta para afilar, el cúter retráctil ''Pretul'' es adecuado para madera suave y dura en muestras pequeñas de laboratorio; el cuchillo ''Ubermann'' es apropiado para el campo, laboratorio y puesto de control, porque tiene una envoltura duradera y láminas intercambiables en caso de pérdida de filo. Conclusiones: La calidad de las imágenes es decisiva en la clasificación de especies maderables, porque permite una mejor visualización y distinción de las características anatómicas en el entrenamiento con los modelos de red neuronal convolucional EfficientNet B0 y Custom Vision, lo cual se evidenció en las métricas de precisión.


Introduction: The great diversity of tropical timber species demands the development of new technologies capable of identifying them based on their patterns or anatomical characteristics. The application of convolutional neural networks (CNN) for the recognition of tropical timber species has increased in recent years due to the promising results of CNNs. Objective: To evaluate the quality of macroscopic images with three cutting tools to improve the visualization and distinction of anatomical features in the CNN model training. Methods: Samples were collected from 2020 to 2021 in areas of logging and sawmills in the Central Jungle, Peru. They were later sized and, after botanical and anatomical identification, cut in cross sections. A database of macroscopic images of the cross-section of wood was generated through cutting with three different tools and observing its performance in the laboratory, field, and checkpoint. Results: Using three cutting tools, we obtained high quality images of the cross section of wood; 3 750 macroscopic images were obtained with a portable microscope and correspond to 25 timber species. We found the ''Tramontina'' knife to be durable, however, it loses its edge easily and requires a sharpening tool, the ''Pretul'' retractable cutter is suitable for cutting soft and hard wood in small laboratory samples and finally the ''Ubermann'' knife is suitable for use in the field, laboratory, and checkpoint, because it has a durable sheath and interchangeable blades in case of dullness. Conclusion: The quality of the images is decisive in the classification of timber species, because it allows a better visualization and distinction of the anatomical characteristics in training with the EfficientNet B0 and Custom Vision convolutional neural network models, which was evidenced in the precision metrics.


Sujets)
Bois/analyse , Microscopie électronique , Écosystème Tropical , Pérou , Apprentissage machine
2.
Rev. biol. trop ; 68(1)mar. 2020.
Article Dans Espagnol | LILACS-Express | LILACS | ID: biblio-1507641

Résumé

Introducción: Swietenia macrophylla King ("caoba") es la especie arbórea de mayor importancia comercial en el sureste mexicano y utilizada como guía en el manejo forestal, por lo que conocer su edad y tasas de crecimiento es fundamental para la sostenibilidad de los aprovechamientos maderables. Objetivos: Estimar laedad (E t ) a partir del método del 'tiempo de paso' (Tp) y calcular las tasas de crecimiento absoluto (TCA) y relativo (TCR) para Swietenia macrophylla en Quintana Roo, México. Métodos: Se ajustaron ecuaciones para calcular TCA y TCR con remediciones periódicas durante 15 años del diámetro normal (d) en 403 árboles de S. macrophylla en Felipe Carrillo Puerto, Quintana Roo, México; también, se determinaron el Tp y la E t para el cálculo del incremento corriente anual (ICA) e incremento medio anual (IMA), y definir así los turnos comercial y técnico. Resultados: La máxima TCR se alcanzó a los 28 cm de d (0.015 cm año-1) (aplicación de aclareos), mientras que la mayor TCA (0.69 cm año-1) y menor Tp (3.5 años) a los 55 cm de d (turno comercial). El máximo ICA al considerar la E t fue de 1.43 cm en la categoría diamétrica de 50 cm, con un IMA de 0.67 cm año-1 a una edad de 75 años, mientras que el turno técnico (ICA = IMA) se alcanzó a los 96 años (incrementos de 0.78 cm año-1). Conclusiones: A través de mediciones periódicas del diámetro normal en S. macrophylla es posible obtener su edad, además los resultados pueden ser utilizados para elaborar programas de manejo y ejecutar prácticas silvícolas que propicien el incremento diamétrico en Quintana Roo.


Introduction: Swietenia macrophylla King (Mahogany) is the most commercially important tree species in Southeastern of Mexico and is used as a guide in forest management. Therefore, knowing its age and growth rates is essential for the sustainability of timber harvest. Objective: Estimate the age (Et) from the 'step time' (Tp) method and calculate the absolute (TCA) and relative (TCR) growth rates for Swietenia macrophylla in Quintana Roo, Mexico. Methods: Equations were adjusted to calculate TCA and TCR with periodic re-measured for 15 years of the normal diameter (d) in 403 S. macrophylla trees in Felipe Carrillo Puerto, Quintana Roo, Mexico. Tp and Et were determined for the calculation of the annual current increase (ICA) and average annual increase (IMA), to define the commercial and technical shifts. Results: The maximum TCR was reached at 28 cm of d (0.015 cm year-1) (thinning application), whereas the highest TCA (0.69 cm year-1) and lower Tp (3.5 years) at 55 cm of d (commercial shift). The maximum ICA when considering Et was 1.43 cm in the 50 cm of diametric category with an IMA of 0.67 cm year-1 at an age of 75 years, while the technical shift (ICA = IMA) was reached at 96 years (increments of 0.78 cm year-1). Conclusions: Through periodic measurements of the normal diameter in S. macrophylla it is possible to obtain its age, these results also can be used to elaborate management programs and apply silvicultural practices that propitiate the diametric increase in Quintana Roo.

3.
Biosci. j. (Online) ; 36(2): 449-457, 01-03-2020. ilus, tab
Article Dans Anglais | LILACS | ID: biblio-1146271

Résumé

Forest Red Gum eucalypt provides a versatile wood and is converted into different purposes. However, such wood is somewhat limited in structural ends, which highlights the need to exploit this gap through diffusion of mechanical properties of suchtimber. This study aimed to evaluate the effect of moisture content reduction, from 30 to 12%, in physical and mechanical properties of Eucalyptus tereticornis, using Brazilian and American documents, to reinforce the structural potential wood and assisting engineers and architects in decision-making for its best building application. We evaluated two physical and fourteen mechanical properties of Eucalyptus tereticornis at two different moisture contents, following the prescriptions of Brazilian (ABNT NBR 7190: 1997) and North American (ASTM D-143-14: 2014) standards. Thus, 1091 repeats were carried out for all properties. By a moisture reduction, the bulk density and eleven strength properties statistically showed changes such as modulus of rupture (static bending, parallel and perpendicular compressions), modulus of elasticity (perpendicular compression and static bending), shear stress, tangential cleavage, and parallel and perpendicular hardnesses. Then, the Eucalyptus tereticornis timber could be better usable if is further applied for structural construction uses.


Eucalipto de goma vermelha prove uma madeira versátil e é convertido para diferentes propósitos. Porém, essa madeira é um pouco limitada para fins estruturais, o que destaca a necessidade de explorar essa lacuna mediante à difusão das propriedades mecânicas de tal madeira. Os resultados obtidos deverão auxiliar os engenheiros e arquitetos na tomada de decisão para a sua melhor aplicação construtiva. Esse artigo estudou a avaliação de duas propriedades físicas e catorze propriedades mecânicas do Eucalyptus tereticornis em dois teores de umidade, seguindo as prescrições dos documentos normativos brasileiro (ABNT NBR 7190: 1997) e norte-americano (ASTM D-143-14: 2014). Assim, 1091 repetições foram conduzidas para todas essas propriedades. Pela redução de umidade de 30% para 12%, a densidade aparente e onze propriedades de resistência demonstraram estatisticamente mudanças, tais como módulos de ruptura (flexão estática ecompressões paralela e perpendicular), módulos de elasticidade (compressão perpendicular e flexão estática), cisalhamento, fendilhamento e as durezas perpendicular e paralela. Então, a madeira de Eucalyptus tereticornispoderia ser melhor utilizável se for também aplicada para usos construtivos estruturais.


Sujets)
Bois , Eucalyptus , Humidité
4.
Article Dans Chinois | WPRIM | ID: wpr-951176

Résumé

Objective: To investigate some phytochemical constituents and biological activities of twelve samples of Tetrapleura tetraptera (Schumach & Thonn.) taub. and nine samples of Aframomum citratum (C. Pereira) K. Schum fruits collected in the bimodal forest zone (ZONE V), the unimodal forest zone (ZONE IV) and the highlands zone (ZONE III) in Cameroon. Methods: Fresh fruits extracts were obtained by aqueous infusion (100 °C during 15 min) and evaluated by spectrophotometric methods for total polyphenol (TPP), total flavonoids (TFLV) contents and antioxidant (DPPH, total antioxidant capacity by the phosphomolybdenum method, iron reducing power or ferric reducing antioxidant power and inhibition of beta carotene discoloration assays) and anti-inflammatory (inhibitions of protein denaturation and 5-LOX represented by INH.PROT and INH.5- LOX respectively) properties. Principal component analysis was performed. Results: For both species, fruits from ZONE V have the highest TPP, TFLV levels and biological activities. TPP and TFLV content of Aframomum citratum and Tetrapleura tetraptera fruits are positively and significantly (P<0.05) correlated. The biological activities of all extracts (0.25, 2.5, 25, 250 mg/mL) were dosedependent and the extracts have shown strong antioxidant and anti- inflammatory activities, but less than references (ascorbic acid, diclofenac, quercetin, and butylated hydroxytoluene). There was a positive correlation between TPP, TFLV and total antioxidant capacity, ferric reducing antioxidant power, and inhibition of beta carotene discoloration assays, and inverse correlations were observed with the IC

5.
Article Dans Anglais | WPRIM | ID: wpr-846771

Résumé

Objective: To investigate some phytochemical constituents and biological activities of twelve samples of Tetrapleura tetraptera (Schumach & Thonn.) taub. and nine samples of Aframomum citratum (C. Pereira) K. Schum fruits collected in the bimodal forest zone (ZONE V), the unimodal forest zone (ZONE IV) and the highlands zone (ZONE III) in Cameroon. Methods: Fresh fruits extracts were obtained by aqueous infusion (100 °C during 15 min) and evaluated by spectrophotometric methods for total polyphenol (TPP), total flavonoids (TFLV) contents and antioxidant (DPPH, total antioxidant capacity by the phosphomolybdenum method, iron reducing power or ferric reducing antioxidant power and inhibition of beta carotene discoloration assays) and anti-inflammatory (inhibitions of protein denaturation and 5-LOX represented by INH.PROT and INH.5- LOX respectively) properties. Principal component analysis was performed. Results: For both species, fruits from ZONE V have the highest TPP, TFLV levels and biological activities. TPP and TFLV content of Aframomum citratum and Tetrapleura tetraptera fruits are positively and significantly (P<0.05) correlated. The biological activities of all extracts (0.25, 2.5, 25, 250 mg/mL) were dosedependent and the extracts have shown strong antioxidant and anti- inflammatory activities, but less than references (ascorbic acid, diclofenac, quercetin, and butylated hydroxytoluene). There was a positive correlation between TPP, TFLV and total antioxidant capacity, ferric reducing antioxidant power, and inhibition of beta carotene discoloration assays, and inverse correlations were observed with the IC50 (g/mL) of DPPH, INH.5-LOX and INH. PROT assays for both species. Conclusions: The fruits exhibit variabilities and those from ZONE V for both species are economically and healthcare challenging for herbalists, pharmaceutical firms, scientists and consumers. Indeed, most important extraction yield of bioactive compounds correlated with significant biological activities and the use of less material compared with an implementation in other Agro-ecologic Zones with the same results are noted.

6.
Acta amaz ; 49(4): 316-323, out. - dez. 2019.
Article Dans Anglais | LILACS | ID: biblio-1118962

Résumé

Overexploitation is one of the main causes of biodiversity loss and local extinction. In the Brazilian Amazon, the intensive use of high-value timber species is leading to a decline in their populations. When in decline, these species can be replaced by less valuable and more common ones that are more feasible to exploit. We conducted interviews with residents of two communities in a sustainable development reserve in central Amazonia, and used free lists and the cognitive salience index (S) to assess the perceptions of residents regarding the occurrence and purpose of timber exploitation, and to identify possible endangered species in white-sand and terra-firme forests. In addition, to infer possible consequences of logging, we assessed the current population status of timber species cited by residents in forest-plot inventories carried out within the reserve. S-index values and interviewee reports suggested an intensive use of terra-firme timber species and an apparently recent increase in the exploitation of white-sand species, which did not use to be exploited because of their relatively low commercial value. The inventories showed that the white-sand timber species have high relative densities and low S values in contrast to the terra-firme species, which mostly have low relative densities and high S values. Our results highlight the need to identify and monitor relevant timber species in both terra-firme and white-sand forests, and to increase the involvement of the local community in the development of logging management practices. (AU)


Sujets)
Industrie du Bois/effets indésirables , Écosystème Amazonien , Exploitation des Ressources Naturelles , Forêt pluviale
7.
Rev. peru. biol. (Impr.) ; 26(2): 227-234, abr.-jun. 2019. ilus, tab
Article Dans Espagnol | LILACS-Express | LILACS | ID: biblio-1094372

Résumé

En este trabajo es estudiado el efecto de dos densidades de siembra de la palmera aguaje (Mauritia flexuosa L.f.) sobre su crecimiento en altura; cuantificamos la proporción de plantas según sexo y determinamos los requerimientos ecológicos de iluminación y forma de copa del aguaje. El estudio se desarrolló en dos subparcelas con diferente densidad de siembra que fueron monitoreadas por 6 años después de 6 años de haber sido plantadas. Los resultados muestran que los individuos presentan mayor altura promedio y por lo tanto mayor crecimiento a mayor densidad de siembra. Es así que a los 12 años de establecidas las plantaciones, los individuos tuvieron en promedio 15.28 m y 13.1 m de altura a densidades de siembra mayores y menores, respectivamente. La proporción de palmeras fértiles se fue incrementando con el tiempo, siendo por lo general mayor a bajas densidades e incrementando en el tiempo la presencia de plantas femeninas. Existe una marcada competencia entre las copas de las palmeras por requerimientos de luz en las categorías buena y aceptable, por lo que se recomienda continuar con la evaluación y analizar el comportamiento futuro de las palmeras.


In this work, the effect of two planting distances of Mauritia flexuosa on its height is studied, quantified the sex ratio and ecological requirements needed by the species, e.g. light and crown shape. We conducted this study in two plots, each one with a different planting distance, which were monitored throughout 6 years starting after 6 years of the establishment of the plantations. Increased planting distance in between individuals gave increased average height and thus increased growth. Individuals planted with higher vs lower distances grew in average 15.28 m and 13.1 m in height respectively. The proportion of fertile palms increased throughout time and was lower in plantations with higher palm densities. The presence of female individuals increased also with time. There was a strong competition among palm crowns related to light requirements in good and acceptable categories. We recommended to continue with the evaluation and future analysis of this species' behavior.

8.
Article Dans Chinois | WPRIM | ID: wpr-818755

Résumé

Objective To evaluate the effects of WeChat publicity in imported malaria control in timber industry in Zhangjiagang City, so as to provide new ideas for the control of malaria imported from abroad. Methods The data of malaria epidemic in Zhangjiagang City was collected, and the contact way of the overseas personnel in timber industry in Zhangjiagang City were obtained. The knowledge of the prevention and control of malaria was propagandized by WeChat among these personnel, and the awareness situation of malaria control knowledge of this population was investigated by questionnaires before and after the WeChat publicity. In addition, the number of new malaria cases among returnees from abroad in timber industry before and after WeChat publicity was calculated. Results All the links in timber industry in Zhangjiagang City adopted WeChat as the contact way. Before and after the WeChat publicity, 128 and 150 questionnaires were collected, respectively, the awareness rates of malaria control knowledge of the investigated objects were in the range of 7.81%-62.50% and 33.33%-90.00%, respectively, and the differences between the awareness rates on all the questions before and after the WeChat publicity were statistically significant (all P < 0.05). Before the WeChat publicity, there were 6 new malaria cases in the population going aboard in timber industry, whereas no new cases were found after the publicity in this population. Conclusion WeChat publicity plays a good role in the prevention and control of malaria imported from overseas in timber industry in Zhangjiagang City, and this publicity method can be promoted in other industries.

9.
Rev. biol. trop ; 66(3): 1009-1017, jul.-sep. 2018. graf
Article Dans Anglais | LILACS, SaludCR | ID: biblio-977362

Résumé

Abstract Knowledge of spatial patterns and interactions of tree species allows for understanding the ecological processes of spatiotemporal structures of tropical forests, becoming essential for the establishment of strategies for the conservation and management of their resources in the long term. The aim of this study was to investigate the spatial patterns and interactions of Astronium lecointei, Dinizia excelsa and Peltogyne paniculata, three dominant timber tree species in the Jamari National Forest, Rondônia, Brazilian Amazon. The Kernel estimator was used aiming to verify the possible influence of first-order factors on species distributions. Inhomogeneous K-functions were applied to analyze species spatial patterns and interactions by means of second-order factors. Univariate analyses revealed different scale-dependent spatial patterns for the species. Aggregation related to ecological characteristics, such as habitat preference and dispersal limitation, was verified for A. lecointei and P. paniculata. D. excelsa presented a random spatial pattern, explained by specific features of its establishment, such as the need for clearings due to light requirements. Interspecific associations were evidenced by bivariate analyses, in which spatial attraction of species resulted from the same preference for microhabitats and the repulsion was a result of niche segregation. Rev. Biol. Trop. 66(3): 1009-1017. Epub 2018 September 01.


Resumen El conocimiento de los patrones e interacciones espaciales de las especies arbóreas permite la comprensión de los procesos ecológicos de estructuración espacio-temporal de los bosques tropicales, tornándose imprescindible para el establecimiento de estrategias de conservación y manejo de sus recursos a largo plazo. El objetivo de este estudio fue investigar los patrones y las interacciones espaciales de Astronium lecointei, Dinizia excelsa y Peltogyne paniculata, tres especies arbóreas madereras dominantes en la Selva Nacional del Jamari, Rondônia, Amazonia Brasileña. Para ello, se utilizó el estimador Kernel, con el objetivo de verificar la posible influencia de factores de primer orden en la distribución de las especies. Para el análisis de los patrones e interacciones espaciales de las especies por medio de los factores de segundo orden, se empleó la función K no homogénea. Los análisis univariados revelaron diferentes patrones espaciales dependientes de la escala para las especies. Agregación relacionada a características ecológicas, como preferencia de hábitat y limitación de la dispersión, fue constatada para A. lecointei y P. paniculata. Dinizia excelsa presentó un patrón espacial aleatorio, explicado por características particulares de su establecimiento, como la necesidad de claros debido a sus requisitos lumínicos. Las asociaciones interespecíficas fueron evidenciadas por los análisis bivariados, en que la atracción espacial de las especies resultó de la misma preferencia por micro hábitats y la repulsión fue resultado de la segregación de nichos.


Sujets)
Arbres/croissance et développement , Bois , Forêts , Écosystème Amazonien , Science forêt/tendances , Paspalum
10.
Article Dans Chinois | WPRIM | ID: wpr-818877

Résumé

Objective To evaluate the effects of WeChat publicity in imported malaria control in timber industry in Zhangjiagang City, so as to provide new ideas for the control of malaria imported from abroad. Methods The data of malaria epidemic in Zhangjiagang City was collected, and the contact way of the overseas personnel in timber industry in Zhangjiagang City were obtained. The knowledge of the prevention and control of malaria was propagandized by WeChat among these personnel, and the awareness situation of malaria control knowledge of this population was investigated by questionnaires before and after the WeChat publicity. In addition, the number of new malaria cases among returnees from abroad in timber industry before and after WeChat publicity was calculated. Results All the links in timber industry in Zhangjiagang City adopted WeChat as the contact way. Before and after the WeChat publicity, 128 and 150 questionnaires were collected, respectively, the awareness rates of malaria control knowledge of the investigated objects were in the range of 7.81%-62.50% and 33.33%-90.00%, respectively, and the differences between the awareness rates on all the questions before and after the WeChat publicity were statistically significant (all P < 0.05). Before the WeChat publicity, there were 6 new malaria cases in the population going aboard in timber industry, whereas no new cases were found after the publicity in this population. Conclusion WeChat publicity plays a good role in the prevention and control of malaria imported from overseas in timber industry in Zhangjiagang City, and this publicity method can be promoted in other industries.

11.
Rev. biol. trop ; 64(3): 1117-1127, jul.-sep. 2016. tab, ilus
Article Dans Anglais | LILACS | ID: biblio-958200

Résumé

Abstract:The seed dispersal process is a crucial stage in plant regeneration and maintenance of forest biological diversity. While the number of removed seeds is quantitative, the distance to which a seed is removed from its origin is qualitative, because it affects the probability that a seed will germinate and recruit to the next life stage. However, the creation of forest margins can negatively affect the seed dispersal process, especially for largediaspore plant species. In this study, the diaspore removal and dispersal distance of Caryocar coriaceum, a tree with large diaspores that is in danger of extinction, were analyzed. The study was conducted for two consecutive years in a protected forest in Northeastern Brazil. Each year, 1 200 diaspores with a nylon wire and a satin tape yellow were used and equally distributed in 120 experimental stations established on the forest margin and in the interior. During the first year of the study, no differences in diaspore removal and dispersal distance were found among the investigated environments. However, for the second year of the study, the number of removed diaspores differed significantly; nevertheless, the dispersal distance was not different between the forest margin and the interior. The low diaspore removal percentages suggest that species recruitment may be compromised because the diaspore accumulation close to the relatives enables higher fungi and insect attack. In addition, most of the few removed diaspores were found at short distances from their sources (up to 5 m), which can lead to low genetic variability. Virtually no diaspore was found buried by hoarding rodents, and no diaspore was found preyed upon by these animals. Evidence found in this study suggests the local loss of species dispersers, which can compromise the maintenance of forest biological diversity. Rev. Biol. Trop. 64 (3): 1117-1127. Epub 2016 September 01.


ResumenEl proceso de dispersión de semillas es una etapa crucial en la regeneración de las plantas y el mantenimiento de la diversidad biológica de los bosques. Mientras que el número de semillas removidas es cuantitativo, la distancia a la que se elimina una semilla desde su origen es cualitativa, porque afecta la probabilidad de que una semilla germine y sea reclutada para la próxima etapa del ciclo de vida. Sin embargo, la creación de márgenes de los bosques puede afectar negativamente el proceso de dispersión, especialmente para especies de plantas con diásporas grandes. En este estudio, analizamos la remoción diásporas y la distancia de dispersión de C. coriaceum, un árbol de diásporas grandes que está en peligro de extinción. El estudio se llevó a cabo durante dos años consecutivos en un bosque protegido en el Noreste de Brasil. Cada año, un total de 1 200 diásporas fueron igualmente distribuidas, con un hilo de nylon y una cinta amarilla de satén, en 120 estaciones experimentales establecidas en el margen y en el interior del bosque. En el primer año del estudio, no se encontraron diferencias en la remocíon de las diásporas y la distancia de dispersión entre los ambientes estudiados. Sin embargo, en el segundo año el número de diásporas retiradas difería significativamente, pero la distancia de dispersión no fue diferente entre el margen de bosques y el interior. El bajo porcentaje de remoción encontrado sugiere que el reclutamiento de especies puede estar comprometido, ya que la acumulación de diásporas próximas unas de otras es propicio para un mayor ataque de hongos e insectos. Además, la mayoría de las pocas diásporas removidas fueron encontradas a pequeñas distancias de su origen (hasta 5 m), lo que puede generar una baja variabilidad genética. Prácticamente ninguna diáspora fue encontrada enterrada por los roedores recolectores y ninguna estaba depredada por estos animales. La evidencia encontrada en este estudio indica la pérdida local de dispersores de las especies, lo que puede poner en peligro el mantenimiento de la diversidad biológica de los bosques.


Sujets)
Theales/physiologie , Dispersion des plantes/physiologie , Saisons , Graines/physiologie , Facteurs temps , Brésil , Forêts , Biodiversité
12.
Braz. j. biol ; 75(1): 77-85, Jan-Mar/2015. tab, graf
Article Dans Anglais | LILACS | ID: lil-744329

Résumé

Butia purpurascens is an endemic and threatened palm tree species that occurs in open areas of the Brazilian Cerrado, predominantly in southwestern Goiás. The leaves of this palm tree are harvested by local people to fabricate brooms. This study evaluated changes in vegetative and reproductive phenology in two different natural populations of this palm tree: one population with leaf harvesting and another non-harvested population. Twenty plants were monitored in each area for 23 months. The phenophases were related to the temperature and precipitation averages for a 30-year period. Leaf sprouting occurred throughout the year, with a slight reduction in periods of low temperatures and low rainfall. The first spathes emerged in March and flowering began during the dry season (June), continuing until January of the following year, concurrent with the period of most intense fruiting. Flowering and fruiting appear to be triggered by periods of drought, which are commonly observed in the Cerrado. The harvested sites produced significantly fewer leaves, spathes, inflorescences and infructescences than the non-harvested sites. Thus, the supply of resources to the local fauna is possibly reduced in sites under leaf exploitation, which in the long term can represent damage to the palm tree population’s structure and dynamics. Other socioeconomic and ecological studies about the effects of leaf harvesting in B. purpurascens are necessary to enable strategies for sustainable use, devise management alternatives and conserve this threatened palm species.


Butia purpurascens é uma palmeira endêmica e ameaçada que ocorre em áreas de cerrado sentido restrito do sudoeste goiano e tem suas folhas extraídas pela população local para a confecção de vassouras. O estudo avaliou variações na fenologia vegetativa e reprodutiva em duas populações naturais da palmeira em Jataí, GO: uma área sem extração e outra com extrativismo foliar. Vinte indivíduos foram monitorados em cada área durante 23 meses. As fenofases foram relacionadas às medias de temperatura e precipitação por um período de 30 anos. O brotamento foliar ocorreu ao longo de todo o ano, embora tenha reduzido nos períodos de menor temperatura e pluviosidade. A emissão das primeiras espatas se iniciou em março e a floração teve início durante a estação seca (junho), perdurando até janeiro do ano seguinte, concomitante ao período de intensa frutificação. Floração e frutificação parecem ser desencadeadas por períodos de estiagem, comum no Cerrado brasileiro. Áreas com extração produziram número significativamente menor de folhas, espatas, inflorescências e infrutescências do que áreas sem extração. Assim, a oferta de recursos para a fauna local é reduzida em áreas sob extrativismo, o que pode prejudicar a estrutura e a dinâmica populacional da palmeira, em longo prazo. Outros estudos sócio-econômicas e ecológicos sobre os efeitos da extração foliar em B. purpurascens são necessários para permitir estratégias de exploração sustentável, alternativas de manejo e a conservação dessa espécie atualmente ameaçada.


Sujets)
Humains , Arecaceae/croissance et développement , Surveillance de l'environnement , Arecaceae/classification , Arecaceae/physiologie , Brésil , Espèce en voie de disparition , Inflorescence , Densité de population , Reproduction/physiologie , Saisons
13.
Acta amaz ; 45(1): 35-44, jan.-mar. 2015. map
Article Dans Anglais | LILACS, VETINDEX | ID: biblio-1455236

Résumé

Radiometric changes observed in multi-temporal optical satellite images have an important role in efforts to characterize selective-logging areas. The aim of this study was to analyze the multi-temporal behavior of spectral-mixture responses in satellite images in simulated selective-logging areas in the Amazon forest, considering red/near-infrared spectral relationships. Forest edges were used to infer the selective-logging infrastructure using differently oriented edges in the transition between forest and deforested areas in satellite images. TM/Landsat-5 images acquired at three dates with different solar-illumination geometries were used in this analysis. The method assumed that the radiometric responses between forest with selective-logging effects and forest edges in contact with recent clear-cuts are related. The spatial frequency attributes of red/near infrared bands for edge areas were analyzed. Analysis of dispersion diagrams showed two groups of pixels that represent selective-logging areas. The attributes for size and radiometric distance representing these two groups were related to solar-elevation angle. The results suggest that detection of timber exploitation areas is limited because of the complexity of the selective-logging radiometric response. Thus, the accuracy of detecting selective logging can be influenced by the solar-elevation angle at the time of image acquisition. We conclude that images with lower solar-elevation angles are less reliable for delineation of selecting logging.


Mudanças radiométricas observadas em imagens multitemporais de satélites ópticos têm importante papel na caracterização de áreas afetadas pelo corte seletivo. O objetivo desse estudo foi analisar o comportamento multitemporal da resposta da mistura espectral em imagens de satélite de áreas simuladas por corte seletivo de madeira na floresta amazônica, considerando as relações espectrais do vermelho/infravermelho próximo. Para a análise dos dados foram utilizadas as margens da floresta para inferir a infraestrutura de exploração florestal em diferentes orientações a partir da transição entre áreas de floresta e desmatamento em imagens de satélite. Imagens do sensor TM/Landsat-5 adquiridas em três datas distintas com diferentes geometrias de iluminação solar foram utilizadas na análise. O método utilizado presume que as respostas radiométricas entre a floresta com efeitos do corte seletivo e as margens da floresta em contato com áreas recém-desmatadas estão relacionadas. Os atributos da frequência espacial das bandas espectrais do vermelho/infravermelho próximo foram analisados. A análise dos diagramas de dispersão mostraram dois grupos de pixels que representam áreas de corte seletivo. Os atributos de tamanho e distância radiométrica representando esses dois grupos foram relacionados com o ângulo de elevação solar. Os resultados sugerem que a detecção de áreas exploradas é limitada devido à complexidade da resposta radiométrica do corte seletivo. Assim, a acurácia em detectar o corte seletivo pode ser influenciada pelo ângulo de elevação solar durante a aquisição das imagens. Nós concluímos que imagens com ângulos de elevação solar baixos são menos confiáveis para a delimitação do corte seletivo.


Sujets)
Conservation des ressources naturelles/analyse , Conservation des ressources naturelles/statistiques et données numériques , Forêts , Imagerie satellitaire , Surveillance de l'environnement , Systèmes d'information géographique , Technologie de télédétection
14.
Biol. Res ; 48: 1-17, 2015. graf, tab
Article Dans Anglais | LILACS | ID: biblio-950779

Résumé

BACKGROUND: Excessive production of free radicals causes direct damage to biological molecules such as DNA, proteins, lipids, carbohydrates leading to tumor development and progression. Natural antioxidant molecules from phytochemicals of plant origin may directly inhibit either their production or limit their propagation or destroy them to protect the system. In the present study, Monodora myristica a non-timber forest product consumed in Cameroon as spice was screened for its free radical scavenging properties, antioxidant and enzymes protective activities. Its phenolic compound profile was also realized by HPLC. RESULTS: This study demonstrated that M. myristica has scavenging properties against DPPH',OH',NO', and ABTS'radicals which vary in a dose depending manner. It also showed an antioxidant potential that was comparable with that of Butylated Hydroxytoluene (BHT) and vitamin C used as standard. The aqueous ethanol extract of M. myristica barks (AEH); showed a significantly higher content in polyphenolic compounds (21.44 ± 0.24 mg caffeic acid/g dried extract) and flavonoid (5.69 ± 0.07 quercetin equivalent mg/g of dried weight) as compared to the other studied extracts. The HPLC analysis of the barks and leaves revealed the presence of several polyphenols. The acids (3,4-OH-benzoic, caffeic, gallic, O- and P- coumaric, syringic, vanillic), alcohols (tyrosol and OH-tyrosol), theobromine, quercetin, rutin, catechine and apigenin were the identified and quantified polyphenols. All the tested extracts demonstrated a high protective potential on the superoxide dismutase (SOD), catalase and peroxidase activities. CONCLUSION: Finally, the different extracts from M. myristica and specifically the aqueous ethanol extract reveal several properties such as higher free radical scavenging properties, significant antioxidant capacities and protective potential effects on liver enzymes.


Sujets)
Extraits de plantes/pharmacologie , Piégeurs de radicaux libres/pharmacologie , Épices , Annonaceae/composition chimique , Polyphénols/composition chimique , Antioxydants/pharmacologie , Peroxidases/effets des médicaments et des substances chimiques , Picrates/métabolisme , Acides sulfoniques/métabolisme , Superoxide dismutase/effets des médicaments et des substances chimiques , Flavonoïdes/analyse , Dérivés du biphényle/métabolisme , Techniques in vitro , Cameroun , Extraits de plantes/composition chimique , Catalase/effets des médicaments et des substances chimiques , Forêts , Chromatographie en phase liquide à haute performance , Radical hydroxyle/métabolisme , Feuilles de plante/composition chimique , Écorce/composition chimique , Benzothiazoles/métabolisme , Monoxyde d'azote/métabolisme
15.
Rev. bras. plantas med ; 16(3): 607-617, jul.-set. 2014. tab
Article Dans Portugais | LILACS | ID: lil-722282

Résumé

Pimenta pseudocaryophyllus (Gomes) Landrum é a única espécie representante brasileira deste gênero de Myrtaceae. Tem sido popularmente utilizada no tratamento de diversas enfermidades, assim como condimento e aromatizante de bebidas, por seu sabor muito similar ao cravo-da-índia. Em menor escala, é empregada em carpintaria e na arborização urbana. Diversos autores analisaram a composição química do óleo essencial da espécie em diferentes regiões do Brasil, encontrando eugenol, metileugenol, (E) metilisoeugenol, chavibetol, geranial e neral como composto predominante nos espécimes estudados. Visando ressaltar a importância de P. pseudocaryophyllus como potencial fonte de recursos assim como subsidiar ações de manejo adequado esta revisão apresenta os principais aspectos botânicos, ecológicos, etnobotânicos e farmacológicos da espécie.


Pimenta pseudocaryophyllus (Gomes) Landrum is the only Brazilian species representative of this Myrtaceae genus. It has being traditionally used in the treatment of many diseases as well for seasoning food and flavoring beverages due to its similarity with clove flavor. In a minor scale, it is used in carpentry and as urban tree. Many authors have analyzed the chemical composition of the leaf essential oil in different regions of Brazil, founding eugenol, metileugenol, (E) metilisoeugenol, chavibetol, geranial e neral as main component in the specimens studied. Aiming to highlight the importance of P. pseudocaryophyllus as potential source of natural products and to provide some base to the adequate management actions, a review on botanical, ecological, ethnobotanical and pharmacological aspects of this species is presented.


Sujets)
Ethnobotanique/classification , Actions pharmacologiques , Pimenta/métabolisme , Huile essentielle/analyse , Polygonum/classification
16.
Rev. biol. trop ; 61(3): 1415-1424, sep. 2013. ilus, graf, tab
Article Dans Anglais | LILACS | ID: lil-688485

Résumé

The neotropical palm Euterpe precatoria is subject to extraction for its valuable palm heart. The development of management and conservation practices for this species requires understanding of its population structure, dynamics, and traditional use across the range of environments it inhabits, from different successional stages in continuous forest to forest fragments. Here, we analyzed how the population structure of E. precatoria varies with successional stage, fragmentation, and exposure to extraction. Since E. precatoria recruitment increases with disturbance, we expected seedling density to be higher in secondary forests and fragments relative to primary forests. The study was conducted from 2007-2008 in the Caribbean Slope of Costa Rica at Braulio Carrillo National Park (BCNP), La Selva Biological Station (LSBS), Manú Center, and Finca El Progreso (FEP). The first two sites had continuous primary and secondary forests (BCNP had one extracted primary forest); the last two consisted of primary forest fragments. Population structure was variable, with greater densities in the extracted primary forest, and in the secondary forests, as compared to primary forests and fragments. Palms <5m across all sites represented 50-90% of the total number of individuals. In sites that suffered historical over-extraction, local communities have lost the tradition of consuming this species. Understanding how population dynamics is affected by extraction and succession is essential to the design of sustainable management programs rooted in community participation.


La palma neotropical Euterpe precatoria sufre un proceso de extracción ilegal debido al sabor y calidad de su palmito. El desarrollo de prácticas de manejo y conservación de esta especie requiere de la comprensión de su estructura y dinámica poblacional en los diferentes ambientes que coloniza. Analizamos cómo la estructura poblacional de E. precatoria varió con el estadio sucesional, la fragmentación y la exposición a la extracción. Esperábamos que la densidad de plántulas fuera mayor en bosques secundarios y fragmentos en relación con los bosques primarios. El estudio se realizó entre 2007-2008 en la vertiente del Caribe de Costa Rica en el Parque Nacional Braulio Carrillo, la Estación Biológica La Selva, el Centro Manú y la Finca El Progreso. Los dos primeros sitios tenían bosques primarios y secundarios continuos (Braulio Carrillo tenía además un bosque primario extraído), mientras que los dos últimos representaban fragmentos de bosques primarios con una historia previa de extracción. La mayor densidad de plántulas se encontró en el bosque primario extraído y en los bosques secundarios, mientras que las palmas reproductivas fueron más comunes en los bosques primarios y en los fragmentos. Las palmas <5m en todos los sitios representaron el 50-90% del número total de individuos. En los sitios que históricamente sufrieron sobre-extracción, las comunidades perdieron la tradición de consumir esta especie. Comprender los factores que afectan la estructura poblacional es esencial para el diseño de programas de gestión sostenible basados en la participación comunitaria.


Sujets)
Humains , Arecaceae/croissance et développement , Conservation des ressources naturelles , Activités humaines , Arbres/croissance et développement , Costa Rica , Densité de population
17.
Ciênc. rural ; 43(4): 610-615, abr. 2013. ilus, tab
Article Dans Portugais | LILACS | ID: lil-669380

Résumé

Este trabalhou objetiva apresentar uma metodologia analítica para o cálculo dos módulos de elasticidade longitudinal (E) e transversal (G) em vigas de madeira de dimensões estruturais, segundo o emprego das teorias de vigas de Euler Bernoulli e Timoshenko, sendo utilizado o ensaio de flexão estática a três pontos. As madeiras testadas foram o Pinus elliottii e a Corymbia citriodora. Os resultados encontrados relevaram ser o módulo de elasticidade longitudinal 18,70 vezes superior ao módulo transversal do Pinus elliottii e 21,2 superior ao módulo transversal do Corymbia citriodora, sendo estes compatíveis quando comparada a relação entre E e G estabelecida pela norma Brasileira ABNT NBR 7190:1997 (Projeto de Estruturas de Madeira), que define ser o módulo de elasticidade longitudinal vinte vezes superior ao transversal.


This paper proposed a test method to obtain the shear (G) and longitudinal (E) modulus of elasticity in timber beams with structural dimensions, based on the static three-points bending tests and the Euler Bernoulli and Timoshenko beams theories. The woods tested were the Corymbia citriodora and Pinus elliottii. The results revealed that the longitudinal modulus of elasticity of Pinus elliottii is 18.70 greater than the shear modulus, and 21.16 greater than the shear modulus of Corymbia citriodora, being consistent this results when compared to the proposed by the Brazilian standard ABNT NBR 7190:1997 (Design of Wood Structures), being the longitudinal modulus of elasticity twenty times greater than the shear modulus.

18.
Article Dans Anglais | IMSEAR | ID: sea-162613

Résumé

A study to assess changes in the physical and chemical properties of soil in timber saw mill dumpsite was carried out in Abakaliki between 2007 and 2008. Results showed that soil textural class remained sandy loamy. The lowest soil bulk density of 1.34 and 1.20 g cm-3 were obtained in the unburnt dumpsite in 2007 and 2008 resulting to 12% and 20% decline in 2007 and 2008 in the unburnt dumpsite relative to cropped land. The total porosity and gravimetric moisture content was a reverse of the soil bulk density. Higher total porosity and gravimetric moisture content were obtained in the unburnt and burnt dumpsites in that order relative to the fallow and cropped land. Infiltration rate followed the same trends as total porosity of the various sites. The lowest infiltration rate 15.02 and 35.82 mmhr-1 was observed in the cropped land. The soil pH decreased with depth in the dump and non-dumpsite but became strongly acid at 30 – 60 cm and 60 – 90 cm depths. The order of soil organic matter content was unburnt dumpsite > burnt dumpsite > fallow > cropped land. The available P and exchangeable K and Ca were highest in the burnt dumpsite. Heavy metals (Zn, Cu, Fe, and Pb) increased with time in the burnt and unburnt dumpsites but decreased in the cropped land. More concentration of heavy metals was observed in the 0 – 30 cm soil depth. The relative performance of maize grown on soils of the dump and non-dumpsites showed that there was better growth in the dump sites soils. However, the concentrations of heavy metals on tissue were found to be within normal range. Therefore, long term dumping of sawmill waste can influence soil properties and productivity.

19.
Ciênc. rural ; 42(6): 981-986, jun. 2012. tab
Article Dans Portugais | LILACS | ID: lil-640732

Résumé

Visando a contribuir para o melhor entendimento da participação da atividade extrativista no âmbito da comercialização de bromélias no Brasil, apresentou-se resultado de pesquisa que buscou: a) identificar e caracterizar os extrativistas de bromélias formalmente registrados e os informais no Estado do Paraná; b) identificar e caracterizar as metodologias de coleta, o preparo e vias de comercialização das plantas coletadas; c) levantar a opinião dos extrativistas sobre facilidades e dificuldades desta atividade. O extrativismo de bromélias no Paraná foi identificado em 12 municípios, englobando 31 famílias extratoras, predominantemente concentradas no litoral do Paraná (n=10) e Município de Ortigueira (n=7). Foram identificados dois tipos básicos de extrativistas: residente e oportunista, com diferenças marcantes entre estes, especialmente no que se refere a volume e forma de extração. Foram identificadas 21 espécies submetidas ao extrativismo, sendo as mais frequentemente coletadas: Vriesea incurvata Gaudich. comercializada por 90% dos entrevistados, Nidularium innocentii Lem. (77%), Vriesea platynema Gaudich. (67%), Tillandsia stricta Sol. ex Ker Gawl. (55%) e Vriesea carinata Lem. (55%).


Aiming to contribute to the better understanding of the wild harvesting participation in the context of the bromeliads trade, the results from a study focused on: a) identifying and to characterizing the bromeliads wild harvesters (formally and not formally registered) in the State of the Paraná; b) identifying and characterizing the harvesting methodologies, preparation and trade routes, and c) surveying the harvesters opinion on the facilities and difficulties of bromeliads wild harvesting are presented. The bromeliads wild harvesting was detected in 12 municipalities at Parana State, involving 31 harvester families, most of them concentrated at the coastal zone (n=10) and Ortigueira Mun. (7). Two basic harvester types were identified: resident and opportunist with outstanding differences between them especially related to volume and forms of extraction. A total of 21 bromeliads species were identified as submitted to wild harvesting, being the more frequently collected: Vriesea incurvata Gaudich. (cited by 90% of the interviewed harvesters), Nidularium innocentii Lem. (77%), Vriesea platynema Gaudich. (67%), Tillandsia stricta Sol. ex Ker Gawl. (55%) and Vriesea carinata Wawra (55%).

20.
Rev. bras. entomol ; 56(1): 47-53, jan.-mar. 2012. ilus
Article Dans Portugais | LILACS | ID: lil-624626

Résumé

Description of last larval instar and pupa of Epacroplon cruciatum (Aurivillius) (Coleoptera, Cerambycidae, Cerambycinae) and biological notes. Last larval instar and pupa of South American Hexoplonini Epacroplon cruciatum (Aurivillius, 1899) are described and illustrated. Biological notes are also presented.


Descrição da larva de último instar e pupa de Epacroplon cruciatum (Aurivillius) (Coleoptera, Cerambycidae, Cerambycinae) e notas biológicas. Último instar larval e pupa do Hexoplonini sul-americano Epacroplon cruciatum (Aurivillius, 1899) são descritos, ilustrados e disponibilizadas notas biológicas.

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