985 resultados para Tropical Brazilian wood species
Resumo:
Presents morphological and natural history data on Epipedobates pictus and three additional taxa currently regarded as synonyms of the former: Epipedobates braccatus, E. flavopictus and E. hahneli. Morphological data on tadpoles and adults, in addition to distribution patterns and vocalizations, indicate that the four taxa represent distinct species. -from Authors
Resumo:
Patterns of dietary and foraging strata utilization by the ground ant community of a Brazilian cocoa planatation were examined using sugar, meat and flour baits on the surface as well as buried. A total of 49 ant species was recorded, including 10 species of Pheidole. Strong dominance was exercised by Solenopsis geminata at both surface and subterranean strata, and at all food resources. The dissimilarity matrix of the epigaeic ant fauna was much greater than that for the hypogaeic species. At least four guilds were identified: the fungus-growing ants, epigaeic nectivores, epigaeic carnivores, and hypogaeic foragers. Niche breadth reduction, leading to the formation of guilds, permits the coexistence of many species in the this ground ant community from a tropical cocoa plantation. -Authors
Resumo:
The present paper presents the chromosome numbers of five brazilian species of diplopods: Plusioporus setiger (2n = 10 and 2n= 10+ lB, the distinction of the sexual pair was not possible), Pseudonannolene ophiulus (2n=12, XY), Pseudonannolene halophila (2n=16, XY), Rhinocricus sp. (2n=28, XY) and Rhinocricus padbergi (2n=20, the distinction of the sexual pair was not possible).
Resumo:
Two populations of Chaetophora elegans (Roth) C. Agardh and two of Stigeoclonium helveticum Vischer were investigated for microhabitat characteristics and morphological variation in streams of Sao Paulo State, southeastern Brazil. Different patterns of microhabitat distribution were found between species investigated. Populations of C. elegans were distributed under relatively narrow microhabitat conditions (high irradiance, low depth, moderate to high current velocity, rocky substrata and lower values of niche width) and showing little morphometric variation (colony diameter, main axis cell size, and apical branch number). Stigeoclonium helveticum occurred under more diverse microhabitat conditions, revealed by lack of significant difference between sampling units with and without the alga and wider niche width, but also exhibited relatively narrow morphometric variation (plant length, main axis cell and lateral branch cell sizes). The narrow microhabitat conditions and smaller niche width of C. elegans can explain its low abundance (percentage cover) in streams from the area studied as well as in other regions of Sao Paulo State. In contrast, the wider variation of microhabitat conditions and the higher niche widths of S. helveticum suggest that this green alga is able to grow in a high number of stream ecosystems in the region investigated, ranging from undisturbed to highly disturbed habitats. Thus, the results suggest that S. helveticum is a generalist species.
Resumo:
We investigated if differences in morphological characters in two species of Metrodorea (Rutaceae) from Brazilian semideciduous forests correspond to some pollination divergence. M. nigra and M. stipularis are sympatric species, display a similar floral morphology, are protandrous, self-incompatible, their flower periods overlap, and both are pollinated by flies. M. nigra main pollinators are Pseudoptiloleps nigripoda (Muscidae) and Fannia sp. (Fanniidae); M. stipularis major pollinators are Phaenicia eximia (Calliphoridae), Palpada sp. and Ornidia obesa (Syrphidae). The distinct floral odor (disagreeable in M. nigra and sweet in M. stipularis) and color (brownish violet vs. pale yellow) determine the differences on type and number of floral visitors observed. Several species from semideciduous forests initially considered to be pollinated by diverse insects, present flies as main pollinators, stressing the importance of fly pollination in such habitats.
Resumo:
The year 2000 marks 500 years of massive destruction for the Brazilian Atlantic Forest, as a consequence of the European colonization of Brazil. Today, the Atlantic Forest is restricted to ca 98,800 km2 of remnants, or 7.6 percent of its original extension. The Atlantic Forest continues to suffer under severe anthropogenic pressure, risking imminent extinction of the remaining species. Our current knowledge indicates that this complex biome contains a species diversity higher than most of the Amazon forests, and also has high levels of endemism. The 13 selected articles in this special issue present data on the natural history, ecology, sustainable management, and conservation of the Atlantic Forest. These articles represent a sample of the research conducted to date in the region and suggest avenues of future research, particularly with regard to conservation alternatives for the remaining portions of the Atlantic Forest. This special issue represents one of the first general references pertaining to the Brazilian Atlantic Forest.
Resumo:
The new flavonoid glycoside kaempferol-3-O-α-L-rhamnopyranosyl(1→2)-O-[α-L- rhamnopyranosyl(1→6)]-O-β-D-galactopyranoside-7-O-α-L- rhamnopyranoside was isolated together with (S)-zierin from the leaves of Zollernia ilicifolia (Fabaceae), a medicinal plant used as analgesic and antiulcerogenic effects in Brazilian Tropical Atlantic Rain Forest. The structures were established on the basis of 1H, 13C NMR and 2D NMR (COSY, HMBC, HMQC), UV, MS and IV spectra. The infusion of Zollernia ilicifolia was qualitatively compared to the infusion of the espinheiras-santas (Maytenus aquifolium and Maytenus ilicifolia) by HPLC-DAD.
Resumo:
The reproductive phenology of seven species of Rubiaceae from the Brazilian Atlantic rain forest was compared to evaluate the occurrence of phylogenetic constraints on flowering and fruiting phenologies. Since phenological patterns can be affected by phylogenetic constraints, we expected that reproductive phenology would be similar among plants within a family or genus, occurring during the same time (or season) of the year. Observations on flowering and fruiting phenology were carried out monthly, from December 1996 to January 1998, at Núcleo Picinguaba, Parque Estadual da Serra do Mar, Ubatuba, São Paulo State, Brazil. Nine phenological variables were calculated to characterize, quantify and compare the reproductive phenology of the Rubiaceae species. The flowering patterns were different among the seven species studied, and the Kruskal-Wallis test indicated significant differences in flowering duration, first flowering, peak flowering and flowering synchrony. The peaks and patterns of fruiting intensity were different among the Rubiaceae species studied and they differed significantly from conspecifics in the phenological variables fruiting duration, fruiting peak date, and fruiting synchrony (Kruskal-Wallis test). Therefore, we found no evidence supporting the phylogenetic hypotheses, and climate does not seem to constrain flowering and fruiting patterns of the Rubiaceae species in the understory of the Atlantic forest.
Resumo:
Over the past few years there have significantly been increased the articles that approach the constructions in wood or with structure in wood in the specialized Brazilian magazines. This increase brings up indications that the incorporated values to these habitations are modifying, however it is not so simple to conclude that these issues can be associated to the development of incorporated technologies to the constructive system. The work presents, firstly, a survey performed in these publications that had the objective to verify which the constructive systems in wood is being more executed, under which cultural and technician standards. From that survey it was performed a study of the habitations constructed in mixing system whose structures are timbers and walls in masonry. The aesthetic and cultural questions involved are argued considering mainly that these habitations belong to a social class whose purchasing power increased.
Resumo:
Visual communication seems to be widespread among nocturnal anurans, however, reports of these behaviors in many Neotropical species are lacking. Therefore, we gathered information collected during several sporadic field expeditions in central and southern Brazil with three nocturnal tree frogs: Aplastodiscus perviridis, Hypsiboas albopunctatus and H. bischoffi. These species displayed various aggressive behaviors, both visual and acoustic, towards other males. For A. perviridis we described arm lifting and leg kicking; for H. albopunctatus we described the advertisement and territorial calls, visual signalizations, including a previously unreported behavior (short leg kicking), and male-male combat; and for H. bischoffi we described the advertisement and fighting calls, toes and fingers trembling, leg lifting, and leg kicking. We speculate about the evolution of some behaviors and concluded that the use of visual signals among Neotropical anurans may be much more common than suggested by the current knowledge. © 2007 Departamento de Ciências Biológicas.
Resumo:
Soil seed banks are considered an important mechanism for natural regeneration in tropical forest ecosystems. This paper investigated the soil seed bank in two semideciduous seasonal tropical forest fragments with different disturbance histories in Botucatu, southeastern Brazil. In each study site, 40 superficial soil samples (30 cm × 30 cm × 5 cm) were taken at the end of both the dry and rainy seasons. The seeds were estimated by the germination method. Average soil seed density was 588.6 and 800.3 seeds m-2, respectively, for site 1 (less disturbed) and site 2 (more disturbed). Seed density and diversity (H′) were significantly higher in site 2 in both seasons. Non-woody taxa predominated in both fragments, but pioneer tree species were better represented in the less disturbed forest. Both ecosystems have a potential for regeneration from soil seed banks, but this potential is higher in the less disturbed site. Low richness and density of pioneer tree species in the seed bank indicate that the ecosystem has lost its resilience. The seed bank is not as important in these ecosystems as in other forests. Results indicate that management strategies to restore these forests should take into account the possibility of recovering soil seed bank processes and dynamics. © 2007 Elsevier B.V. All rights reserved.
Resumo:
Neea theifera Oerted (Nyctaginaceae), Guapira noxia Linn. (Nyctaginaceae) and Hancornia speciosa Gomes (Apocynaceae) are plant species found in Brazilian Cerrado used popularly for the treatment of gastric ulcers. Here they are assessed for mutagenic activity by analysis of the reverse mutations induced in Salmonella typhimurium strains TA100, TA98, TA102 and TA97a, by extracts of the plants, with and without metabolic activation. Methanol and chloroform extracts of N. theifera and G. noxia and methanolic and aqueous extracts of H. speciosa were tested at five different concentrations. It was found that only the methanolic extract of H. speciosa exhibited a positive mutagenic effect, on strains TA98 and TA100 in the absence of metabolic activation. The phytochemical analysis of the species suggested that condensed tannins are the main compounds responsible for the observed effect.
Resumo:
Background. Species identification and antifungal susceptibility tests were carried out on 212 Candida isolates obtained from bloodstream infections, urinary tract infections and dialysis-associated peritonitis, from cases attended at a Brazilian public tertiary hospital from January 1998 to January 2005. Findings. Candida albicans represented 33% of the isolates, Candida parapsilosis 31.1%, Candida tropicalis 17.9%,Candida glabrata 11.8%, and others species 6.2%. In blood culture, C. parapsilosis was the most frequently encountered species (48%). The resistance levels to the antifungal azoles were relatively low for the several species, except for C. tropicalis and C. glabrata. Amphotericin B resistance was observed in 1 isolate of C. parapsilosis. Conclusions. The species distribution and antifungal susceptibility herein observed presented several epidemiological features common to other tertiary hospitals in Latin American countries. It also exhibited some peculiarity, such as a very high frequency of C. parapsilosis both in bloodstream infections and dialysis-associated peritonitis. C. albicans also occurred in an important number of case infections, in all evaluated clinical sources. C. glabrata presented a high proportion of resistant isolates. The data emphasize the necessity to carry out the correct species identification accompanied by the susceptibility tests in all tertiary hospitals. © 2010 Bagagli et al; licensee BioMed Central Ltd.
Resumo:
Because anuran species are highly dependent on environmental variables, we hypothesized that anuran species richness and the number of reproductive modes from different Brazilian localities vary according to climatic and altitudinal variables. Published data were compiled from 36 Brazilian localities and climatic and altitudinal data were extracted from an available database. A partial redundancy analysis (pRDA) showed that 23.5% of the data set's variation was explained by climatic and altitudinal data, while the remaining 76.5% remained unexplained. This analysis suggests that other factors not analysed herein may also be important for predicting anuran species richness and the number of reproductive modes in Brazil. Altitude and total annual rainfall were positively correlated with anuran species richness and the number of reproductive modes, and total annual rainfall was strongly associated with these two biotic variables in the triplot of pRDA. The positive association of total annual rainfall and the negative association of the concentration of annual rainfall were already expected based on physiological and reproductive requirements of anurans. On the other hand, temperature was not associated with richness or the number of reproductive modes. Copyright © 2010 Cambridge University Press.