105 resultados para Atlantic Coastal Forest

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo


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In tropical forests, the environmental heterogeneity can provide niche partitioning at local scales and determine the diversity and plant species distribution. Thus, this study aimed to investigate the variations of tree species structure and distribution in response to relief and soil profile features in a portion of the largest remnant of Brazilian Atlantic rain forest. All trees >= 5 cm diameter at breast height were recorded in two 0.99 ha plots. Topographic survey and a soil characterization were accomplished in both plots. Topsoil samples (0-20 cm) were taken from 88 quadrats and analyzed for chemical and particle size properties. Differences for both diversity and tree density were identified among three kinds of soils. A canonical correspondence analysis (CCA) indicated that the specific abundance varied among the three kinds of soils mapped: a shallow Udept - Orthent / Aquent gradient, probably due to differences in soil drainage. Nutrient content was less likely to affect tree species composition and distribution than relief, pH, Al3+, and soil texture. Some species were randomly distributed and did not show restriction to relief and soil properties. However, preferences in niche occupation detected in this study, derived from the catenary environments found, rise up as an important explanation for the high tree species diversity in tropical forests.

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Site-specific height-diameter models may be used to improve biomass estimates for forest inventories where only diameter at breast height (DBH) measurements are available. In this study, we fit height-diameter models for vegetation types of a tropical Atlantic forest using field measurements of height across plots along an altitudinal gradient. To fit height-diameter models, we sampled trees by DBH class and measured tree height within 13 one-hectare permanent plots established at four altitude classes. To select the best model we tested the performance of 11 height-diameter models using the Akaike Information Criterion (AIC). The Weibull and Chapman-Richards height-diameter models performed better than other models, and regional site-specific models performed better than the general model. In addition, there is a slight variation of height-diameter relationships across the altitudinal gradient and an extensive difference in the stature between the Atlantic and Amazon forests. The results showed the effect of altitude on tree height estimates and emphasize the need for altitude-specific models that produce more accurate results than a general model that encompasses all altitudes. To improve biomass estimation, the development of regional height-diameter models that estimate tree height using a subset of randomly sampled trees presents an approach to supplement surveys where only diameter has been measured.

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The aim of this work is to use GIS integration data to characterize sedimentary processes in a SubTropical lagoon environment. The study area was the Canan,ia Inlet estuary in the southeastern section of the Canan,ia Lagoon Estuarine System (CLES), state of So Paulo, Brazil (25A degrees 03'S/47A degrees 53'W). The area is formed by the confluence of two estuarine channels forming a bay-shaped water body locally called "Trapand, Bay". The region is surrounded by one of the most preserved tracts of Atlantic Rain Forest in Southwestern Brazil and presents well-developed mangroves and marshes. In this study a methodology was developed using integrated a GIS database based on bottom sediment parameters, geomorphological data, remote sensing images, Hidrodynamical Modeling data and geophysical parameters. The sediment grain size parameters and the bottom morphology of the lagoon were also used to develop models of net sediment transport pathways. It was possible to observe that the sediment transport vectors based on the grain size model had a good correlation with the transport model based on the bottom topography features and Hydrodynamic model, especially in areas with stronger energetic conditions, with a minor contribution of finer sediments. This relation is somewhat less evident near shallower banks and depositional features. In these regions the organic matter contents in the sediments was a good complementary tool for inferring the hydrodynamic and depositional conditions (i.e. primary productivity, sedimentation rates, sources, oxi-reduction rates).

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The environment most diverse in harvestmen species is the Atlantic Forest of Sao Paulo. However, there remains a lack of studies regarding their communities in certain regions. Among these regions is one south of the Paranapiacaba mountain range in the state of Sao Paulo, the Parque da Onca Parda (POP). Through nocturnal collections and pitfall traps, the region's harvestmen community has been studied. The observed richness of this site included 27 species, with dominance of three species: Holcobunus nigripalpis Roewer, 1910, Neosadocus maximus (Giltay, 1928) and Munequita sp., accounting for 68.4% of harvestmen abundance. This makes the diversity of POP more similar to the semideciduous Atlantic Forest communities of the interior than to those of the Coastal Atlantic Forest that contains the park. Its geographic location places it within the Southern Sao Paulo State (SSP) area of endemism, along with the Parque Turistico do Alto Ribeira (PETAR), with which it shares up to 12% similarity regarding harvestmen fauna. Richness and abundance of harvestmen were positively related to temperature and humidity. The period of animal activity (as measured by abundance and richness) varied throughout the night, being highest in the early hours during both studied seasons (summer and winter).

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The Brazilian Atlantic forest is considered one of the world's biodiversity conservation hotspot. Today there is less than ten percent remaining. Therefore it is necessary to restore these ecosystems. There are many ways of achieving restoration's main goals, but there is a lack of ecological studies that analyzes tree species richness as a variable. Thus, this study's goal is to investigate if there is a difference between a forest restoration in a gradient of tree species richness that varies from 20, 60 to 120 species, by using the litterfall as an indicator. Every month, for one year the forest litter was collected from litter traps that were previously installed. Results revealed that stands produced litterfall by the increasing gradient of species was of 5,370, 5,909 and 6,432 kg ha(-1) yr(-1). The statistical analyses revealed no significant difference among them. Therefore this six-year-old forest restoration plantation shows no difference on the litter production by the tree species richness.

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Theoretical and empirical studies demonstrate that the total amount of forest and the size and connectivity of fragments have nonlinear effects on species survival. We tested how habitat amount and configuration affect understory bird species richness and abundance. We used mist nets (almost 34,000 net hours) to sample birds in 53 Atlantic Forest fragments in southeastern Brazil. Fragments were distributed among 3 10,800-ha landscapes. The remaining forest in these landscapes was below (10% forest cover), similar to (30%), and above (50%) the theoretical fragmentation threshold (approximately 30%) below which the effects of fragmentation should be intensified. Species-richness estimates were significantly higher (F = 3715, p = 0.00) where 50% of the forest remained, which suggests a species occurrence threshold of 30-50% forest, which is higher than usually occurs (<30%). Relations between forest cover and species richness differed depending on species sensitivity to forest conversion and fragmentation. For less sensitive species, species richness decreased as forest cover increased, whereas for highly sensitive species the opposite occurred. For sensitive species, species richness and the amount of forest cover were positively related, particularly when forest cover was 30-50%. Fragment size and connectivity were related to species richness and abundance in all landscapes, not just below the 30% threshold. Where 10% of the forest remained, fragment size was more related to species richness and abundance than connectivity. However, the relation between connectivity and species richness and abundance was stronger where 30% of the landscape was forested. Where 50% of the landscape was forested, fragment size and connectivity were both related to species richness and abundance. Our results demonstrated a rapid loss of species at relatively high levels of forest cover (30-50%). Highly sensitive species were 3-4 times more common above the 30-50% threshold than below it; however, our results do not support a unique fragmentation threshold.

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The environment most diverse in harvestmen species is the Atlantic Forest of São Paulo. However, there remains a lack of studies regarding their communities in certain regions. Among these regions is one south of the Paranapiacaba mountain range in the state of São Paulo, the Parque da Onça Parda (POP). Through nocturnal collections and pitfall traps, the region's harvestmen community has been studied. The observed richness of this site included 27 species, with dominance of three species: Holcobunus nigripalpis Roewer, 1910, Neosadocus maximus (Giltay, 1928) and Munequita sp., accounting for 68.4% of harvestmen abundance. This makes the diversity of POP more similar to the semideciduous Atlantic Forest communities of the interior than to those of the Coastal Atlantic Forest that contains the park. Its geographic location places it within the Southern São Paulo State (SSP) area of endemism, along with the Parque Turístico do Alto Ribeira (PETAR), with which it shares up to 12% similarity regarding harvestmen fauna. Richness and abundance of harvestmen were positively related to temperature and humidity. The period of animal activity (as measured by abundance and richness) varied throughout the night, being highest in the early hours during both studied seasons (summer and winter).

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Baccharis compreende ca. 340 espécies distribuídas nas Américas. O indumento em tufos diminutos, formado por tricomas com uma única célula basal, e as flores funcionalmente unissexuais são caracteres diagnósticos do gênero. No estado do Rio de Janeiro ocorrem 55 espécies de Baccharis. O trabalho apresenta os resultados de estudos taxonômicos de Baccharis subgen. Molina (Pers.) Heering para a flora fluminense. No estado, o subgênero está representado por 18 espécies pertencentes a quatro seções - Caulopterae (8 spp.), Molinae (4 spp.), Baccharidastrum (3 spp.) e Trinervatae (3 spp.). É apresentada uma chave para a identificação das seções e espécies e descrições morfológicas, ilustrações, dados de distribuição geográfica e ecologia. Três espécies são novos registros e cinco são excluídas da lista de espécies do Rio de Janeiro.

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The composition of the ant fauna was examined in public squares of three municipalities that compose the hydrographic basin of the Upper Tiete River: Biritiba Mirim, Salesopolis, and Mogi das Cruzes. Richness, frequency of occurrence, similarity, and influence of seasons on the species composition were examined. The method was standardized as sampling units consisted of a set of three baits arranged in a triangle with vertices two meters apart. Sardines in oil were used as attractant. A total of 86 species was collected. Myrmicinae and Pheidole were the richest subfamily and genus, respectively. Eighty species were collected in Mogi das Cruzes, 49 in Salesopolis, and 45 in Biritiba Mirim, with 34 species common to the three areas. The ordination analysis (NMDS) revealed the presence of two distinct communities: one in Mogi das Cruzes and another in Biritiba Mirim-Salesopolis. These data were supported by the dendogram based on the Bray-Curtis dissimilarity index. This result might be associated with the distinct geographic and demographic characteristics of the areas. Regarding seasonality, the composition of the fauna of Mogi das Cruzes is independent of the season of the year, unlike the observed in Biritiba Mirim and Salesopolis.

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Four sediment cores were sampled from Lake Arari, located on Marajo Island at the mouth of the Amazon River. The island's vegetation cover is composed mainly of Amazon coastal forest, herbaceous and varzea vegetation. The integration of data on sedimentary structures, pollen, carbon and nitrogen isotope records, C/N ratios and radiocarbon ages allowed the identification of changes in vegetation and the sources of organic matter accumulated in the lake during the Holocene. The data indicate a relatively high flow energy, marine water influence and the presence of mangroves during the lagoon phase between 8990 and 8690 cal yr B.P. and 2310-2230 cal yr B.P. Between 2310 and 2230 cal yr B.P. and similar to 1000 cal yr B.P., the flow energy decreased and the mangroves were replaced by herbaceous vegetation following the decline in marine influence, likely due to the increase in freshwater river discharge. During the last 1000 years, Lake Arari was established in association with the expansion of herbaceous vegetation and the dominance of freshwater algae. (C) 2011 Elsevier BM. All rights reserved.

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As part of an ongoing revision of the family Gonyleptidac, we have identified many species that are synonyms of previously described species or misplaced in this family. This article summarizes these findings, adding previously unavailable information or correcting imprecise observations to justify the presented taxonomic changes. The following new familial or subfamilial assignments are proposed: Nemastygnus Roewer, 1929 and Taulisa Roewer, 1956 are transferred to Agoristenidae, Agoristeninae; Napostygnus Roewer, 1929 to Cranaidae; Ceropachylinus peruvianus Roewer, 1956 and Pirunipygus Roewer, 1936 are transferred to Gonyleptidae, Ampycinae; Gyndesops Roewer, 1943, Haversia Roewer, 1913 and Oxapampeus Roewer, 1963 are transferred to Gonyleptidae, Pachylinae. The following generic synonymies are proposed for the family Gonyleptidae: Acanthogonyleptes Mello-Leitao, 1922 = Centroleptes Roewer, 1943; Acrographinotus Roewer, 1929 = Unduavius Roewer, 1929; Gonyleptes Kirby, 1819 = Collonychium Bertkau, 1880; Mischonyx Bertkau, 1880 = Eugonyleptes Roewer, 1913 and Gonazula Roewer, 1930; Parampheres Roewer, 1913 = Metapachyloides Roewer, 1917; Pseudopucrolia Roewer, 19 12 = Meteusarcus Roewer, 1913; Haversia Roewer, 19 13 = Hoggellula Roewer, 1930. The following specific synonymies are proposed for the family Gonyleptidae: Acanthogonyleptes singularis (Mello-Leitao, 1935) = Centroleptes flavus Roewer, 1943, syn. n.; Geraeocormobius sylvarum Holmberg, 1887 = Discocyrtus serrifemur Roewer, 1943, syn. n.; Gonyleptellus bimaculatus (Sorensen, 1884) = Gonyleptes cancellatus Roewer, 1917, syn. n.; Gonyleptes atrus Mello-Leitao, 1923 = Weyhia brieni Giltay, 1928, syn. n.; Gonyleptes fragilis Mello-Leitao, 1923 = Gonyleptes banana Kury, 2003, syn. n.; Gonyleptes horridus Kirby, 1819 = Collonychium bicuspidatum Bertkau, 1880, syn. n., Gonyleptes borgmeyeri Mello-Leitao, 1932, syn. n., Gonyleptes curvicornis Mello-Leitao, 1932, syn. n., Metagonyleptes hamatus Roewer, 1913, syn. n. and Paragonyleptes simoni Roewer, 1930, syn. n.; Gonyleptes pustulatus Sorensen, 1884 = Gonyleptes guttatus Roewer, 1917, syn. n.; Haversia defensa (Butler, 1876) = Sadocus vallentini Hogg, 1913, syn. n.; Liogonyleptoides minensis (Piza, 1946) = Currala bahiensis Soares, 1972, syn. n.; Megapachylus grandis Roewer, 1913 = Metapachyloides almeidai Soares & Soares, 1946, syn. n.; Mischonyx cuspidatus (Roewer, 1913) = Gonazula gibbosa Roewer, 1930 syn. n.; Mischonyx scaber (Kirby, 1819) = Xundarava holacantha Mello-Leitao, 1927, syn. n.; Parampheres tibialis Roewer, 1917 = Metapachyloides rugosus Roewer, 1917, syn. n.; Parapachyloides uncinatus (Sorensen, 1879) = Goyazella armata Mello-Leitao, 1931, syn. n.; Pseudopucrolia mutica (Perry, 1833) = Meteusarcus armatus Roewer, 1913, syn. n. The following new combinations are proposed: Acrographinotus ornatus (Roewer, 1929), comb. n. (ex Unduavius); Gonyleptellus bimaculatus (Sorensen, 1884), comb. n. (ex Gonyleptes); Gonyleptes perlatus (Mello-Leitao, 1935), comb. n. (ex Moojenia); Mischonyx scaber (Kirby, 1819), comb. n. (ex Gonyleptes); and Neopachyloides peruvianus (Roewer, 1956), comb. n. (ex Ceropachylus). The following species of Gonyleptidae, Gonyleptinae are revalidated: Gonyleptes atrus Mello-Leitao, 1923 and Gonyleptes curvicornis (Roewer, 1913).

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A new species of Oreobates is described from Cavernas do Peruacu National Park, Januaria, Minas Gerais state, in the Atlantic Dry Forests of Brazil. The new species is distinguished from all other Oreobates by having the following combination of characters: large tympanum, discs broadly enlarged and truncate on Fingers III and IV, smooth dorsal skin, nuptial pads absent, snout subacuminate, and a very short pulsatile (2-3 pulses) single-noted advertisement call with dominant frequency of about 3150 Hz, and no harmonic structure. Molecular phylogenetic analyses using partial sequences of the mitochondrial genes cytochrome b (cyt b) and 16S using multiple outgroups recovered the new species within Oreobates and sister to O. heterodactylus. The latter species inhabits the Dry Forests of Mato Grosso (Cerrado) and Bolivia (Chiquitano forests), and is strictly associated to these habitats, which suggests a preterit connection between Chiquitano and Atlantic Dry Forests. The discovery of a new Oreobates in the Atlantic Dry Forest is of great importance for the conservation of these dry forests, as it is known only from this type of habitat.

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As ticks spend most of their time off-host, the environment is a major selective force of these parasites. In fact, human impact on landscapes has favored a minority of tick species which became well-known pests. However, this is an ongoing process and novel pests may arise. We herein report a surrogate life cycle of a neotropical tick species. Amblyomma ovate, and which may be related to an increased risk of human rickettsiosis. Under natural conditions, adults of this tick species feed on carnivores and exhibit non-nidicolous ambush behavior, whereas larvae and nymphs feed on small rodents and birds. In an anthropized spot within an Atlantic rainforest reserve of Brazil, an A. ovate population exhibited a nidicolous behavior with all 3 tick stages feeding on the dog. This dog's infestation was outstandingly high, and it displayed the highest anti-Rickettsia titers and harbored Rickettsia-infected ticks. (c) 2012 Elsevier GmbH. All rights reserved.

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Flight activity of foragers of four colonies of Plebeia remota (Holmberg, 1903) was registered from December 1998 to December 1999, using an automated system (photocells and PLC system). The colonies originated from two different regions: Cunha, state of Sao Paulo, and Prudentopolis, state of Parana, Brazil. Flight activity was influenced by different climatic factors in each season. In the summer, the intensity of the correlations between flight activity and climatic factors was smaller than in the other seasons. During the autumn and winter, solar radiation was the factor that most influenced flight activity, while in the spring, this activity was influenced mainly by temperature. Except in the summer, the various climatic factors similarly influenced flight activity of all of the colonies. Flight activity was not affected by geographic origin of the colonies. Information concerning seasonal differences in flight activity of P. remota will be useful for prediction of geographic distribution scenarios under climatic changes.

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Ocotea catharinensis is a basal angiosperm and an endangered tree species from the Brazilian Atlantic Rain Forest. Despite its economical and ecological importance, mass-propagation of this species is hampered by seldom-produced short-lived seeds, and in vitro propagation is challenged by frequently malformed somatic embryos. Therefore, O. catharinensis somatic embryos are also a good experimental material to study the physiological and molecular mechanisms underlying in vitro morphogenesis. In an ongoing effort to characterize genes expressed during somatic embryogenesis of O. catharinensis we have cloned two Ocotea WUSCHEL-related genes. According to our RT-PCR data, both genes were preferentially expressed in embryogenic cell aggregates. One of them, OcWUS, is a possible ortholog of the Arabidopsis WUSCHEL (WUS) gene, which codes for a homeodomain-containing protein involved in the specification and maintenance of the shoot apical meristem. We analyzed the expression patterns of OcWUS and OcWOX4 by RT-PCR, and OcWUS expression was also assessed by in situ hybridization. The expression patterns of OcWUS were very similar to those described for the Arabidopsis WUS. OcWUS transcripts were generally restricted to a small group of cells in the center of the putative shoot apical meristem of O. catharinensis somatic embryos. Perturbed expression of OcWUS might be related to abnormally formed somatic embryos of O. catharinensis obtained through tissue culture.