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Can native vegetation recover after slash pine cultivation in the Brazilian Savanna?

ABREU, Rodolfo Cesar Real de; ASSIS, Geissianny Bessao de; FRISON, Sergianne; AGUIRRE, Andrea; DURIGAN, Giselda
Fonte: ELSEVIER SCIENCE BV Publicador: ELSEVIER SCIENCE BV
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.42%
There is a widespread view that forest plantations with exotic species are green deserts, unable to sustain biodiversity. Few studies have demonstrated, however, that planted stands of exotic trees have a greater negative effect on the plant diversity of savanna vegetation. We compared the native woody flora under four stands of slash pine of about 45 years old with four stands where the previously existing native Cerrado vegetation was preserved and protected from disturbances for the same period, has changed into dense vegetation - the ""cerradao"", at Assis municipality, Sao Paulo State, Brazil. Aiming at understanding the potential ecological filters driving these communities, we assessed air and soil humidity, light availability and classified the native species on the basis of shade tolerance, dispersal syndrome and biomes in which they occur (Atlantic Forest or Cerrado). We recorded an average of 70 (+/- 13) species under pine stands and 54 (+/- 16) species in cerradao. Of the total of 136 species recorded, 78 occurred in both habitats, eight were exclusive to the ""cerradao"" (shade tolerant and also occurring in forest ecosystems) and 18 were recorded only under pine stands (82% heliophytic, exclusive to the Cerrado biome). Among the functional attributes and abiotic variables analyzed...

Chemically Resolved Particle Fluxes Over Tropical and Temperate Forests

Farmer, Delphine K; Chen, Qi; Kimmel, Joel R; Docherty, Kenneth S; Eiko, Nemitz; Artaxo Netto, Paulo Eduardo; Cappa, Christopher D; Martin, Scot T; Jimenez, Jose L
Fonte: Taylor & Francis; Philadelphia Publicador: Taylor & Francis; Philadelphia
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.07%
Chemically resolved submicron (PM1) particlemass fluxes were measured by eddy covariance with a high resolution time-of-flight aerosolmass spectrometer over temperate and tropical forests during the BEARPEX-07 and AMAZE-08 campaigns. Fluxes during AMAZE-08 were small and close to the detection limit (<1 ng m−2 s−1) due to low particle mass concentrations (<1 μg m−3). During BEARPEX-07, concentrations were five times larger, with mean mid-day deposition fluxes of −4.8 ng m−2 s−1 for total nonrefractory PM1 (Vex,PM1 = −1 mm s−1) and emission fluxes of +2.6 ng m−2 s−1 for organic PM1 (Vex,org = +1 mm s−1). Biosphere–atmosphere fluxes of different chemical components are affected by in-canopy chemistry, vertical gradients in gas-particle partitioning due to canopy temperature gradients, emission of primary biological aerosol particles, and wet and dry deposition. As a result of these competing processes, individual chemical components had fluxes of varying magnitude and direction during both campaigns. Oxygenated organic components representing regionally aged aerosol deposited, while components of fresh secondary organic aerosol (SOA) emitted. During BEARPEX-07, rapid incanopy oxidation caused rapid SOA growth on the timescale of biosphere-atmosphere exchange. In-canopy SOA mass yields were 0.5–4%. During AMAZE-08...

Ocorrência de Migdolus fryanus (Coleoptera: Cerambycidae) em plantios de Pinus caribaea var. hondurensis

Wilcken, Carlos Frederico; Orlato, Cassiano; Ottati, Angelo Luiz Tadeu
Fonte: Sociedade de Investigações Florestais Publicador: Sociedade de Investigações Florestais
Tipo: Artigo de Revista Científica Formato: 171-173
POR
Relevância na Pesquisa
36.25%
Larvas de Migdolus fryanus Westwood (Coleoptera: Cerambycidae) foram encontradas danificando raízes de mudas de P. caribaea var. hondurensis (Sénéel) Barr. & Golf. no Estado de São Paulo. Isso aumenta a importância dessa espécie, cujos danos, em espécies florestais, têm aumentado, principalmente, em plantios de eucalipto. Esse é o primeiro registro de M. fryanus em plantios de Pinus, e o referido inseto pode ser considerado uma nova praga dessa espécie florestal. Detalhes das características morfológicas e biológicas, danos e possíveis métodos de controle de M. fryanus são discutidos.; Larvae of Migdolus fryanus Westwood (Coleoptera: Cerambycidae) were found damaging roots of young plants of P. caribaea hondurensis (Sénéel) Barr. & Golf. in the State of São Paulo, Brazil. This fact increases the importance of this species because the damages have been increasing in forest species specially in eucalyptus plantations. This is the first record of M. fryanus in pine plantations and this insect can be considered a pest of pine plants. Details on the morphology and biological characteristics, damage and possible control methods to M. fryanus are discussed.

Attraction of ambrosia beetles (Coleoptera : Scolytidae) to different tropical pine species in Brazil

Flechtmann, CAH; Ottati, ALT; Berisford, C. W.
Fonte: Amer Entomol Soc Publicador: Amer Entomol Soc
Tipo: Artigo de Revista Científica Formato: 649-658
ENG
Relevância na Pesquisa
46.58%
Ambrosia beetles are the predominant Scolytidae in Brazil. Little is known about the attractiveness of exotic conifer tree volatiles to native scolytids. Objectives were to compare the attractiveness of logs with and without bark of Pinus oocarpa Schiede, P. caribaea variety bahamensis Barrett & Golfari, P, car. variety caribaea Barrett & Golfari and P. car. variety hondurensis Barrett & Golfari over time to native scolytids in different pine stands, to compare the relative attractiveness of logs relative to ethanol traps, to determine how long it takes for logs to become attractive to ambrosia beetles and when attraction peaks occur, and to determine if volatiles released by live standing trees would mask volatiles released by logs of the same species. In young stands, Hypothenemus was the predominant insect genus, whereas in older stands Xyleborus predominated. Debarked logs trapped more beetles than logs with bark. Pine log species attractiveness was not influenced by volatiles present in the stand. Beetles were divided into the following 3 groups, based on response to log volatiles and ethanol: (1) species attracted to ethanol and not responding to pine terpenes Ambrosiodmus hagedorni (Iglesia), A. retusus (Eichhoff), X. spinulosus Blandford...

Charcoal production using tropical pine thinnings

Pontinha, Ananias de Almeida Saraiva; Veiga, Ricardo Antonio de Arruda; Leão, Alcides Lopes
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 757-760
ENG
Relevância na Pesquisa
46.32%
In Brazil, the wood from pine-plantation thinnings is difficult to sell. However, these wood thinnings could be used to produce charcoal. The physical and chemical properties of charcoal produced from logs or first and fourth thinnings of Pinus caribaea var. hondurensis and Pinus oocarpa were determined. Similar properties were also determined for sawmill slabs cut from first and fourth thinnings. Properties were compared to charcoal made from pine materials and 7-yr-old Eucalyptus grandis. Results show that Pinus spp had better chemical properties than did E. grandis. In contrast, charcoal obtained from E. grandis had higher values of apparent density and lower values of bulk density than did Pinus spp. © 1992.

Relações hídricas de duas coníferas tropicais; Water relations of two tropical conifers

Caroline Signori Müller
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 23/02/2015 PT
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36.07%
Diversos modelos climáticos predizem mudanças no regime hídrico e secas extremas nos mais variados ecossistemas, dentre esses, as florestas tropicais nebulares (FTNs), que são apontadas como ambientes sensíveis às mudanças no clima. Nas FTNs a frequência e intensidade de neblina são determinantes na composição da vegetação. As predições são de que o aquecimento terrestre causará um deslocamento da área atual de ocorrência de neblina para altitudes maiores, acima da maioria das FTNs do mundo. Com diminuição da neblina nesses ambientes é provável que ocorra um aumento da evapotranspiração e estresse hídrico da vegetação, podendo haver mortalidade das plantas. Em nosso estudo investigamos as relações hídricas de duas coníferas que ocorrem em FTNs A. angustifolia e P. lambertii, além disso avaliamos se o ponto de perda de turgor (Ψtlp) é um bom preditor de mortalidade para essas espécies. Para compreendermos os efeitos da neblina no status hídrico de A. angustifolia avaliamos duas populações em altitudes diferentes, sendo elas, montanha (1950 m) e vale (1500 m). Os indivíduos localizados na montanha mantiveram potenciais hídricos menos negativos do que os localizados no vale, durante todo o período de monitoramento. Conduzimos um experimento em casa de vegetação para avaliar a resistência a seca de A. angustifolia e P. lambertii. Também avaliamos a importância da absorção de água da neblina pelas folhas (AAF) e do aporte hídrico diretamente no solo na recuperação do status hídrico dessas espécies depois de submetidas à secas em que seu potencial hídrico foliar (ΨFolha) chegou ao ponto de perda de turgor (Ψtlp). As duas espécies apresentaram diferentes estratégias de manutenção do status hídrico...

Evaluation of dimensional stability of tropical pine species

Trianoski,Rosilani; Matos,Jorge Luis Monteiro de; Iwakiri,Setsuo; Prata,José Guilherme
Fonte: Instituto de Florestas da Universidade Federal Rural do Rio de Janeiro Publicador: Instituto de Florestas da Universidade Federal Rural do Rio de Janeiro
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2013 EN
Relevância na Pesquisa
46.51%
The objective of this research was to evaluate the dimensional stability of tropical pine species and establish correlations between shrinkage, anisotropy, and density. Seven species of tropical pines were utilized: Pinus caribaea var. bahamensis, Pinus caribaea var. caribaea, Pinus caribaea var. hondurensis, Pinus chiapensis, Pinus maximinoi, Pinus oocarpa, and Pinus tecunumanii; Pinus taeda was also used as reference. The samples were from 17 and 18-year-old experimental plantings located in the municipalities of Ventania, State of Parana and Itararé, State of Sao Paulo. Dimensional stability was evaluated according to the COPANT 462 (1972c) norm. The results indicated that Pinus chiapensis is an unstable species (Ac > 2.6), and that other tropical pine species and Pinus taeda presented low average stability (2.1 to 2.5). There were no strong correlations between the properties proposed probably due to the presence of resin and extractives, which can alter density and inhibit contraction.

Tree-ring isotope records of tropical cyclone activity

Miller, Dana L.; Mora, Claudia I.; Grissino-Mayer, Henri D.; Mock, Cary J.; Uhle, Maria E.; Sharp, Zachary
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
26.4%
The destruction wrought by North Atlantic hurricanes in 2004 and 2005 dramatically emphasizes the need for better understanding of tropical cyclone activity apart from the records provided by meteorological data and historical documentation. We present a 220-year record of oxygen isotope values of α-cellulose in longleaf pine tree rings that preserves anomalously low isotope values in the latewood portion of the ring in years corresponding with known 19th and 20th century landfalling/near-coastal tropical storms and hurricanes. Our results suggest the potential for a tree-ring oxygen isotope proxy record of tropical cyclone occurrence extending back many centuries based on remnant pine wood from protected areas in the southeastern U.S.

Genetic factors associated with population size may increase extinction risks and decrease colonization potential in a keystone tropical pine

del Castillo, Rafael F; Trujillo-Argueta, Sonia; Sánchez-Vargas, Nahúm; Newton, Adrian C
Fonte: Blackwell Publishing Ltd Publicador: Blackwell Publishing Ltd
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
36.07%
Pioneer species are essential for forest regeneration and ecosystem resilience. Pinus chiapensis is an endangered pioneer key species for tropical montane cloud forest regeneration in Mesoamerica. Human activities have severely reduced some P. chiapensis populations, which exhibited a small or null colonization potential suggesting the involvement of genetic factors associated with small populations. We explored the relationships between (i) population genetic diversity (allozymes) and population size, including sampling size effects, (ii) fitness estimates associated with colonization potential (seed viability and seedling performance) in a common environment and population size, and (iii) fitness estimates and observed heterozygosity in populations with sizes spanning five orders of magnitude. All the estimates of genetic diversity and fitness increased significantly with population size. Low fitness was detected in progenies of small populations of disturbed and undisturbed habitats. Progenies with the lowest observed heterozygosity displayed the lowest fitness estimates, which, in turn, increased with heterozygosity, but seed viability peaked at intermediate heterozygosity values suggesting inbreeding and outbreeding depression. Inbreeding depression appears to be the most immediate genetic factor in population decline. Conservation efforts should try to maintain large and genetically diverse populations...

Temperate Pine Barrens and Tropical Rain Forests Are Both Rich in Undescribed Fungi

Luo, Jing; Walsh, Emily; Naik, Abhishek; Zhuang, Wenying; Zhang, Keqin; Cai, Lei; Zhang, Ning
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 29/07/2014 EN
Relevância na Pesquisa
26.71%
Most of fungal biodiversity on Earth remains unknown especially in the unexplored habitats. In this study, we compared fungi associated with grass (Poaceae) roots from two ecosystems: the temperate pine barrens in New Jersey, USA and tropical rain forests in Yunnan, China, using the same sampling, isolation and species identification methods. A total of 426 fungal isolates were obtained from 1600 root segments from 80 grass samples. Based on the internal transcribed spacer (ITS) sequences and morphological characteristics, a total of 85 fungal species (OTUs) belonging in 45 genera, 23 families, 16 orders, and 6 classes were identified, among which the pine barrens had 38 and Yunnan had 56 species, with only 9 species in common. The finding that grass roots in the tropical forests harbor higher fungal species diversity supports that tropical forests are fungal biodiversity hotspots. Sordariomycetes was dominant in both places but more Leotiomycetes were found in the pine barrens than Yunnan, which may play a role in the acidic and oligotrophic pine barrens ecosystem. Equal number of undescribed fungal species were discovered from the two sampled ecosystems, although the tropical Yunnan had more known fungal species. Pine barrens is a unique...

Resampling of Permanent Pine Rockland Vegetation Plots on Big Pine Key

Sah, Jay P.; Snyder, James R.; Ross, Michael S.; Ogurcak, Danielle
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica Formato: application/pdf
Relevância na Pesquisa
36.46%
The pine rocklands of South Florida are characterized by an herbaceous flora with many narrowly endemic taxa, a diverse shrub layer containing several palms and numerous tropical hardwoods, and an overstory of south Florida slash pine (Pinus elliottii var. densa). Fire has been considered as an important environmental factor for these ecosystems, since in the absence of fire these pine forests are replaced by dense hardwood communities, resulting in loss of the characteristic pineland herb flora. Hence, in the Florida Keys pine forests, prescribed fire has been used since the creation of the National Key Deer Refuge. However, such prescribed burns were conducted in the Refuge mainly for fuel reduction, without much consideration of ecological factors. The USGS and Florida International University conducted a research study for four years, from 1998 to 2001, the objective of which was to document the response of pine rockland vegetation to a range of fire management options and to provide Fish and Wildlife Service and other land managers with information useful in deciding when and where to burn to perpetuate these unique pine forests. This study is described in detail in Snyder et al. (2005).

Phyto-exploration in arid subtropical, arid mediterranean and tropical savanna environments: biogeochemical mechanisms and implications for mineral exploration.

Reid, Nathan
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2009
Relevância na Pesquisa
36.25%
Vegetation sampling is an effective exploration technique in areas of transported cover where other techniques have been of limited success. Several plant species were sampled along transects across 9 known Au ore bodies; Triodia pungens was found give a Au, As, ±Zn, ±S, ±Ce and ±La signature which represented mineralisation through cover materials and Eucalyptus brevifolia was found to give a geobotanical and ±Ca, ±Mg, P, S and Zn signature of underlying geological structure. The Hyperion prospect was used as a ‘blind’ target as there was no background information available until after interpretation was carried out. Mineralisation was located at the contact between granite and dolerite, biogeochemical signatures from E. brevifolia and Acacia bivenosa showed areas of change in ±Au, Ba, Ce, ±Cu, La, ±Mn, Nd, P, S, Sm, Y and Zn which corresponded to this contact. All species in the Pine Creek Orogen were able to present areas elevated in Au, As, ±Zn, ±S, ±Mo and ±Cu which provide future drilling targets. Biogeochemical sampling was able to determine the location of mineralisation at each site and identify underlying substrate changes, however, background knowledge relating to regolith, geology, hydrology and geophysics are important in aiding the interpretation of the elemental data as each component of the substrate influences the elements which a plant will uptake. Mineral exploration in Australia has been driven by the search for large ore deposits close to the surface. This has led to the need to develop technologies for detecting mineral deposits under cover...

Leaves of Lolium multiflorum 'Lema' and tropical tree species as biomonitors of polycyclic aromatic hydrocarbons

Rinaldi, Mirian C. S.; Domingos, Marisa; Dias, Ana P. L.; Esposito, Jessica B. N.; Pagliuso, Josmar Davilson
Fonte: ACADEMIC PRESS INC ELSEVIER SCIENCE; SAN DIEGO Publicador: ACADEMIC PRESS INC ELSEVIER SCIENCE; SAN DIEGO
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.19%
This study extends the current knowledge regarding the use of plants for the passive accumulation of anthropogenic PAHs that are present in the atmospheric total suspended particles (TSP) in the tropics and sub-tropics. It is of major relevance because the anthropic emissions of TSP containing PAHs are significant in these regions, but their monitoring is still scarce. We compared the biomonitor efficiency of Lolium multiflorum 'Lema' and tropical tree species (Tibouchina pukka and Psidium guajava 'Paluma') that were growing in an intensely TSP-polluted site in Cubatao (SE Brazil), and established the species with the highest potential for alternative monitoring of PAHs. PAHs present in the TSP indicated that the region is impacted by various emission sources. L. multiflorum showed a greater efficiency for the accumulation of PAH compounds on their leaves than the tropical trees. The linear regression between the logBCF and logKoa revealed that L. multiflorum is an efficient biomonitor of the profile of light and heavy PAHs present in the particulate phase of the atmosphere during dry weather and mild temperatures. The grass should be used only for indicating the PAHs with higher molecular weight in warmer and wetter periods. (C) 2012 Elsevier Inc. All rights reserved.; Petrobras (Brazilian Petroleum Company); Petrobras (Brazilian Petroleum Company)

Evaluation of potential use of species of tropical pine and eucalyptus for UF plywood manufacture; ; AVALIAÇÃO DO POTENCIAL DE USO DE ESPÉCIES DE PÍNUS TROPICAIS E EUCALIPTO NA PRODUÇÃO DE PAINÉIS COMPENSADOS UREICOS

Iwakiri, Setsuo; Universidade Federal do Paraná; Sanches, Felipe Gustavo; PPGEF/UFPR; Potulski, Daniele Cristina; PPGEF/UFPR; Silva, Janice Bernardo; PPGEF/UFPR; de Andrade, Mário; PPGEF/UFPR; Marchesan, Raquel; PPGEF/UFPR
Fonte: FUPEF DO PARANÁ Publicador: FUPEF DO PARANÁ
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Artigo Avaliado pelos Pares Formato: application/pdf
Publicado em 14/05/2012 POR
Relevância na Pesquisa
46.81%
This research was developed in order to evaluate the quality of plywood manufactured from veneers of five species of tropical pine and nine species of eucalyptus. The plywood was manufactured with five veneers of 2.0 mm thickness, using urea-formaldehyde resin with amount of glue spread of 360 g/m². The boards were pressed at pressure of 10 kgf/cm², temperatures of 110 ºC and pressing time of 8 minutes. It was evaluated the properties of glue line shear strength (RLC) and static bending (MOE and MOR), parallel and perpendicular. Among tropical pine species, P. oocarpa and P. tecunumannii presented the best results in relation to mechanical properties of the boards. For the eucalyptus species best results were obtained by E. saligna, E. viminalis and E. dunnii. All the tropical pine and eucalyptus species evaluated in this research presented boards mechanical properties statistically equal or greater when compared to referential species - Pinus taeda. The results revealed the feasible use of such species veneers for plywood manufactures to internal applications.; Esta pesquisa teve como objetivo avaliar a qualidade dos painéis compensados multilaminados produzidos a partir de lâminas de madeira de cinco espécies de pínus tropicais e nove espécies de eucalipto. Foram produzidos em laboratório painéis compensados com cinco lâminas de 2...

Longitudinal variation of basic density of wood of tropical pine species; VARIAÇÃO LONGITUDINAL DA DENSIDADE BÁSICA DA MADEIRA DE ESPÉCIES DE PINUS TROPICAIS

Trianoski, Rosilani; UFPR, Curitiba, PR, Brasil; Matos, Jorge Luis Monteiro; UFPR, Curitiba, PR, Brasil; Iwakiri, Setsuo; UFPR, Curitiba, PR, Brasil; Prata, José Guilherme; UFPR, Curitiba, PR, Brasil
Fonte: FUPEF DO PARANÁ Publicador: FUPEF DO PARANÁ
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Artigo Avaliado pelos Pares Formato: application/pdf
Publicado em 13/09/2013 POR
Relevância na Pesquisa
46.46%
The wood properties knowledge has fundamental importance since it is associated to many processing and using ways. In this context, this paper aims to evaluate longitudinal variation of basic density of wood of tropical pines species. It evaluated seven species of tropical pines: Pinus caribaea var. bahamensis, Pinus caribaea var. caribaea, Pinus caribaea var. hondurensis, Pinus chiapensis, Pinus maximinoi, Pinus oocarpa, Pinus tecunumanii, beyond Pinus taeda (reference), collected in experimental plantations at 17 and 18 years of age, located in the regions of Itararé (SP) and Ventania (PR). Five trees were selected by species, which were sectioned at positions 0%, 25%, 50%, 75% and 100% of the commercial height for samples. Basic density was determined according to the standard 461 of Comisión Panamericana de Normas Técnicas, besides the percentage of latewood, quantified by Windendro software, based on analysis of scanned images of disks of different positions. The results revealed that all species presented low basic density (0.389 to 0.489 g/cm3) with coefficients of variation between 5.09% to 9.77%, and can be considered promising for commercial scale cultivation, in this way increasing the wood supply for different segments of timber industry.; O conhecimento das propriedades da madeira é de fundamental importância...

Plywood manufacturing from tropical pine glued with phenol formaldehyde resin.; PRODUÇÃO DE PAINÉIS COMPENSADOS DE PINUS TROPICAIS COLADOS COM RESINA FENOL-FORMALDEÍDO

Iwakiri, Setsuo; UFPR; Matos, Jorge Luis Monteiro de; Lima, Adauto José Miranda de; Ferreira, Érika da Silva; Batista, Djeison César; Romão, Sílvia Aparecida Ângelo
Fonte: FUPEF DO PARANÁ Publicador: FUPEF DO PARANÁ
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Artigo Avaliado pelos Pares Formato: application/pdf
Publicado em 11/09/2009 POR
Relevância na Pesquisa
36.07%
. This research was developed with the objective to evaluate the potential uses of the veneer of Pinus chiapensis, Pinus caribaea var. hondurensis, Pinus maximinoi, Pinus oocarpa e Pinus tecunumannii, for plywood munafacturing. The experimental panels were manufactured using five veneers with 2,0 mm thickness and phenol-formaldehyde resin. The board qualities were evaluated based in the glue line shear strength – dry and boiling water tests and static bending tests. The results showed that plywood manufactured with veneer of Pinus. caribaea and Pinus tecunumannii presented the better results of glue line shear strength, modulus of elasticity and rupture in static bending tests in comparison to board made from Pinus taeda and commercial plywood of pinus. The results of glue line shear strength of the Pinus caribaea, Pinus oocarpa and Pinus tecunumannii attend to minimum requirement of the EN 314:1993. The boards manufactured with all of the five species of tropical pinus showed the MOR values higher than commercial plywood of pinus.; Este trabalho teve como objetivo avaliar o potencial de utilização de lâminas de Pinus chiapensis, Pinus caribaea var. hondurensis, Pinus maximinoi, Pinus oocarpa e Pinus tecunumannii na produção de painéis compensados. Os painéis foram produzidos com cinco lâminas de 2...

Soil seed bank and the effect of needle litter layer on seedling emergence in a tropical pine plantation

Bueno,Andrea; Baruch,Zdravko
Fonte: Revista de Biología Tropical Publicador: Revista de Biología Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2011 EN
Relevância na Pesquisa
46.46%
The soil seed bank is the basis for community establishment and permanence and plays a primary role in natural restoration of degraded or altered ecosystems. As part of a restoration project, this study aimed to quantify the soil seed bank and to evaluate the effect of the needle litter layer on seedling emergence. Soil samples from a pine plantation were collected at random in the field and set to germinate in a greenhouse. Half of them were covered by a 6cm layer of dead pine needles simulating field conditions. in the field, 20x20cm plots were established, half were left intact and half were cleaned from the litter needles. All four treatments had 15 replicates and seedling emergence was recorded during six months. Soil seed bank density was 1 222/m² from 17 morphotypes. in the field, the number of morphotypes and seedlings was only 9% and 6% respectively, of those emerged in the greenhouse, possibly due to watering and lack of predation in the latter. in both cases, herbs and graminoids were the dominant emerging seedlings, making up to 70-90% of the total. The needle layer didn’t prevent seeds from reaching the soil but strongly reduced (>50%) seedling emergence, although high variability within treatments resulted in no statistically significant differences. These results show that the needle layer hinders germination and/or emergence of seedlings from the seed bank. its removal may be a recommended technique to accelerate natural restoration in pine plantations. Rev. Biol. Trop. 59 (3): 1071-1079. Epub 2011 September 01

Cultivable bacterial diversity along the altitudinal zonation and vegetation range of tropical Eastern Himalaya

Lyngwi,Nathaniel A.; Koijam,Khedarani; Sharma,D.; Joshi,S. R.
Fonte: Revista de Biología Tropical Publicador: Revista de Biología Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2013 EN
Relevância na Pesquisa
46.22%
The Northeastern part of India sprawls over an area of 262 379km² in the Eastern Himalayan range. This constitutes a biodiversity hotspot with high levels of biodiversity and endemism; unfortunately, is also a poorly known area, especially on its microbial diversity. In this study, we assessed cultivable soil bacterial diversity and distribution from lowlands to highlands (34 to 3 990m.a.s.l.). Soil physico-chemical parameters and forest types across the different altitudes were characterized and correlated with bacterial distribution and diversity. Microbes from the soil samples were grown in Nutrient, Muller Hinton and Luria-Bertani agar plates and were initially characterized using biochemical methods. Parameters like dehydrogenase and urease activities, temperature, moisture content, pH, carbon content, bulk density of the sampled soil were measured for each site. Representative isolates were also subjected to 16S rDNA sequence analysis. A total of 155 cultivable bacterial isolates were characterized which were analyzed for richness, evenness and diversity indices. The tropical and sub-tropical forests supported higher bacterial diversity compared to temperate pine, temperate conifer, and sub-alpine rhododendron forests. The 16S rRNA phylogenetic analysis revealed that Firmicutes was the most common group followed by Proteobacteria and Bacteroidetes. Species belonging to the genera Bacillus and Pseudomonas were the most abundant. Bacterial CFU showed positive but insignificant correlation with soil parameters like pH (r=0.208)...

Distribution, habitat and behavior of grasshopper sparrows, Ammodramus savannarum(Passeriformes: Emberizidae) in northeastern Nicaragua

Arguedas-Negrini,Nidia
Fonte: Revista de Biología Tropical Publicador: Revista de Biología Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2001 EN
Relevância na Pesquisa
36.14%
During March and April of 1996, I made field observations of the sedentary subspecies of grasshopper sparrow (Ammodramus savannarum cracens), in 600 points of the pine savannas of northeastern Nicaragua. Isolated individuals were found in the humid depressions, but breeding populations were located exclusively in areas that had suffered a recent fire. Territorial behavior varied in intensity apparently as a function of territory size: the most aggressive males were those trying to defend smaller territories in populations close to Miskito villages, where most of the fires occur. In contrast to what is happening in other parts of Central America, the Nicaraguan grasshopper sparrow may be indirectly protected from extinction by the Miskito’s traditional fire practices.

The influence of humidity, nutrients and light on the establishment of the epiphytic bromeliad Tillandsia guatemalensis in the highlands of Chiapas, Mexico

Castro Hernández,J. C; Wolf,J. H. D; García-Franco,J. G; González-Espinosa,M
Fonte: Revista de Biología Tropical Publicador: Revista de Biología Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/1999 EN
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In the highlands of Chiapas, rapid habitat destruction and alteration threaten epiphytes. Presumably, forest transformation increases open and border-type vegetation, characterized by drier conditions than those prevailing deeper in the forest. If so, mesic epiphytes should be especially affected. We investigated the role of water availability during the growth of a population of the wide-ranging mesic C3 phytotelm bromeliad Tillandsia guatemalensis. Chiapas experiences a pronounced dry season from November to April when average monthly precipitation falls below 30 mm. T. guatemalensis observed in situ released seeds during this interval and high germination rates occurred about seven weeks after the rainy weather returned (over 93%, an observation confirmed in the laboratory). Many of the tiny seedlings disappeared before they could anchor to the substrate, probably flushed off by torrential rains. Over half of the seedlings comprising a naturally established population died during the dry season. High seedling mortality was also deduced from the size-class structure of natural populations. Seedling mortality on bark taken from the tree base up to a height of 1.3 m of bigger trees is similar on two species of oak compared to two species of pine. These barks also possessed high water retaining capacity. Oak bark derived from higher up the tree...