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Abundancia, riqueza e diversidade de abelhas Euglossinae (Hymenoptera, Apidae) em florestas contínuas de terra firme na Amaz?nia Central, Brasil
Oliveira, Marcio Luiz de;Campos, Lúcio Ant?nio de Oliveira;
Revista Brasileira de Zoologia , 1995, DOI: 10.1590/S0101-81751995000300009
Abstract: the fauna of euglossinae bees were studied in two areas of "terra firme" continuous forest in the central amazon. brazil. during one year (september/1989-august/1990) the collections were done fortnightly, using traps with eight kinds of seents baits. the traps were placed in the understory and in the tree crowns. the continuous forest of "terra firme" near manaus are among those with the highest speeies richness of euglossinae in the neotropics. the species richness was higher than that found in other studies carried out in brazil also. one study area had higher species richness and abundance, while species diversity was higher in another one. the diversity was different significally between the two areas.
Floristic composition and structure in one hectare of terra firme forest, Caracaraí, state of Roraima, Brazil  [PDF]
Juan Gabriel Soler Alarcón,Ariane Luna Peixoto
Boletim do Museu Paraense Emílio Goeldi : Ciências Naturais , 2007,
Abstract: A quantitative floristic and phytosociological inventory in a 1 ha of terra firme forest were conducted in the region of the lower rio Branco (01°01’43”S, 62°05’21”W), Roraima, Brazil. This study included trees, lianas and hemiepiphytes with DBH > 10 cm. The average height of the forest was 16,63 m, with canopy trees of 58, 48 e 47 m. The plot had 544 individuals, 194 species, of which five were represented by lianas and two by hemiepiphytes. The richest families were Leguminoseae, Cecropiaceae, Burseraceae, Chrysobalanaceae and Moraceae. The richest genera were Pourouma, Inga, Licania, Protium e Pouteria. The species with highest densities were Clathrotropis macrocarpa, Bocageopsis multiflora, Eschweilera coriacea, Euterpe precatoria, Inga alba, Pourouma cf. tomentosa subsp. apiculata. A total of 17 families and 76 genera were represented by only one individual; 40 genera and 104 species by only one individual. The families with the highest important value (IV) were Leguminosae, Cecropiaceae, Lecythidaceae, Annonaceae e Arecaceae. The highest IV for the species was found in Clathrotropis macrocarpa, Goupia glabra, Bocageopsis multiflora, Eschweilera coriacea, Euterpe precatoria. The basal area was 26,35 m2. The Shannon index (H’) found was 4,66 and the equitability (J) 0,88. This region, which is localized between the rivers Branco and Negro, is said to have been poorly studied with respect of the flora but of probable importance. The data and information presented shows the floristic importance of the forest of terra firme in this area and looks forward to provide tools that will allow to compare this study with similar ones carried out in the Amazon.
Litterfall yield in a tract of terra firme forest adjacent to a mangrove stand on the Ajuruteua peninsula, Bragan a, Pará  [PDF]
Raquel do Espírito Santo Aguiar do Nascimento,Ulf Mehlig,Maria Milena de Oliveira Abreu,Moirah Paula Machado de Menezes
Boletim do Museu Paraense Emílio Goeldi : Ciências Naturais , 2006,
Abstract: The present study focusses on differences in litter production of a terra firme forest fragment and an adjacent mangrove stand on the coast of the Bragan a region. Litterfall was quantified by means of 10 litter traps (0.5 m2) in the mangrove and 10 in terra firme forest, installed along a transect orthogonal to the division between the two ecosystems. Material was collected fortnightly. Litter production in the mangrove forest (11.8 t.ha-1yr-1) was by a third higher than in terra firme forest (8.7 t.ha-1yr-1). Leaves were the most important litter component in both ecosystems (68 e 63% for mangrove and terra firme, respectively). In the mangrove, Rhizophora mangle contributed the major part of litter material. In terra firme, leaves of species of the families Simaroubaceae, Burseraceae e Arecaceae contributed 13, 12 e 11% of the leaf total; 54% of leaves were not identified taxonomically. In the mangrove, reproductive litter components showed seasonal patterns. It was not possible to identify a clear seasonal pattern in R. mangle leaf litter fall. However in mangrove and terra firme, total litter production was higher in dry season.
Compara??o entre florestas de várzea e de terra firme do Estado do Pará
Gama, Jo?o Ricardo Vasconcellos;Souza, Agostinho Lopes de;Martins, Sebasti?o Venancio;Souza, Deoclides Ricardo de;
Revista árvore , 2005, DOI: 10.1590/S0100-67622005000400013
Abstract: floristic groups among arboreous communities were analyzed in different regions of pará state, using 34 different forest inventory (24 on "terra firme" and 10 on "várzea" forests) data basis. the jaccard index was used to calculate the matrix of floristic similarity, which was turned into a euclidean matrix of distance, and the ward method to define groups. through the results it was possible to conclude that the floristic composition of varzea and terra firme forests are quite different. few species occur in both ecosystems; terra firme forest shows a higher tree species richness than varzea forest. there was a cluster tendency of terra firme forests, more related to the anthropic situation and geographic proximity than varzea forests; in general, the forests formed clusters according to a decreasing order of importance, such as: soil hydric saturation, anthropic situation and geographic proximity.
Multi-scale comparisons of tree composition in Amazonian terra firme forests
E. N. Honorio Coronado, T. R. Baker, O. L. Phillips, N. C. A. Pitman, R. T. Pennington, R. Vásquez Martínez, A. Monteagudo, H. Mogollón, N. Dávila Cardozo, M. Ríos, R. García-Villacorta, E. Valderrama, M. Ahuite, I. Huamantupa, D. A. Neill, W. F. Laurance, H. E. M. Nascimento, S. Soares de Almeida, T. J. Killeen, L. Arroyo, P. Nú ez,L. Freitas Alvarado
Biogeosciences (BG) & Discussions (BGD) , 2009,
Abstract: We explored the floristic composition of terra firme forests across Amazonia using 55 plots. Firstly, we examined the floristic patterns using both genus- and species-level data and found that the species-level analysis more clearly distinguishes among forests. Next, we compared the variation in plot floristic composition at regional- and continental-scales, and found that average among-pair floristic similarity and its decay with distance behave similarly at regional- and continental-scales. Nevertheless, geographical distance had different effects on floristic similarity within regions at distances <100 km, where north-western and south-western Amazonian regions showed greater floristic variation than plots of central and eastern Amazonia. Finally, we quantified the role of environmental factors and geographical distance for determining variation in floristic composition. A partial Mantel test indicated that while geographical distance appeared to be more important at continental scales, soil fertility was crucial at regional scales within western Amazonia, where areas with similar soil conditions were more likely to share a high number of species. Overall, these results suggest that regional-scale variation in floristic composition can rival continental-scale differences within Amazonian terra firme forests, and that variation in floristic composition at both scales is influenced by geographical distance and environmental factors, such as climate and soil fertility. To fully account for regional-scale variation in continental studies of floristic composition, future floristic studies should focus on forest types poorly represented at regional scales in current datasets, such as terra firme forests with high soil fertility in north-western Amazonia.
Multi-scale comparisons of tree composition in Amazonian terra firme forests  [PDF]
E. N. Honorio Coronado,T. R. Baker,O. L. Phillips,N. C. A. Pitman
Biogeosciences (BG) & Discussions (BGD) , 2009,
Abstract: We explored the floristic composition of terra firme forests across Amazonia using 55 plots. Firstly, we examined the floristic patterns using both genus- and species-level data and found that the species-level analysis more clearly distinguishes among forests. Next, we compared the variation in plot floristic composition at regional- and continental-scales, and found that average among-pair floristic similarity and its decay with distance behave similarly at regional- and continental-scales. Nevertheless, geographical distance had different effects on floristic similarity within regions at distances <100 km, where north-western and south-western Amazonian regions showed greater floristic variation than plots of central and eastern Amazonia. Finally, we quantified the role of environmental factors and geographical distance for determining variation in floristic composition. A partial Mantel test indicated that while geographical distance appeared to be more important at continental scales, soil fertility was crucial at regional scales within western Amazonia, where areas with similar soil conditions were more likely to share a high number of species. Overall, these results suggest that regional-scale variation in floristic composition can rival continental-scale differences within Amazonian terra firme forests, and that variation in floristic composition at both scales is influenced by geographical distance and environmental factors, such as climate and soil fertility. To fully account for regional-scale variation in continental studies of floristic composition, future floristic studies should focus on forest types poorly represented at regional scales in current datasets, such as terra firme forests with high soil fertility in north-western Amazonia.
Conteúdo dos criadouros larvais e comportamento de adultos de Toxorhynchites (Lynchiella) haemorrhoidalis haemorrhoidalis (Fabricius) (Diptera, Culicidae) numa floresta de terra-firme da Amaz?nia central
Hutchings, Rosa Sá Gomes;
Revista Brasileira de Zoologia , 1995, DOI: 10.1590/S0101-81751995000200009
Abstract: the natural breeding sites of toxorhynchites (lynchiella) haemorrhoidalis haemorihoidalis (fabricius, 1794), in two study areas, were sampled monthly, during a period of one year, in an upland "terra-firme" forest of the central amazon. these natural breeding sites, consisting of water filled palm bracts on the ground, contained invertobrates and vertebrates along with palm inflorescences, leaves and twigs. the inhabitants of the non-submersed area of the bracts include diplopoda, acarina, araneae, pseudoscorpiones, isopoda, blattodea, coleoptera (carabidae, curculionidae, scolytidae, staphilinidae). collembola, dermaptera, diptera (cecidomyidae, drosophilidae, mycetophilidae, tipulidae), hemiptera, hymenoptera and trichoptera. the submersed areas of the bracts were inhabited by oligochaeta, coleoptera (dysticidae, helodidae, histeridae, hydrophilidae, limnebiidae), diptera (ceratopogonidae, chirononiidae, culicidae, psychodidae, stratiomyidae, syrphidae). odonata, along with immature dendrobatidae e hylidae. the ovipositing, resting and feeding behaviors of t. h. haemorrhoidalis adults are described.
Forest spatial heterogeneity and palm richness, abundance and community composition in Terra Firme forest, Central Amazon
Cintra, Renato;Ximenes, Arimatéa de Carvalho;Gondim, Fábio R;Kropf, Marcela S;
Brazilian Journal of Botany , 2005, DOI: 10.1590/S0100-84042005000100007
Abstract: the mechanisms that maintain tree diversity in tropical rain forests are still in debate. variations in forest structural components produce forest microenvironmental heterogeneity, which in turn may affect plant performance and have been scarcely analyzed in the amazon. palms are widespread in the neotropical rainforests and have relatively well known taxonomy, apart from being ecologically and economically important. the understanding of how palms respond to variation in the forest structural components may help to explain their abundance and richness in a given area. in this study, we describe a palm community and analyze how it is affected by forest microenvironmental heterogeneity. in a pristine "terra firme" forest at reserva ducke, manaus, we recorded all adult palm trees in twenty 100 × 10 m plots. in the same plots we recorded the variation in canopy openness, the leaflitter thickness and counted all non-palm forest trees. a total of 713 individuals in 29 palm species were found. the three most abundant species were astrocaryum sciophilum (miq.) pulle, a. gynacanthum mart. and attalea attaleoides (barb. rodr.) wess. boer. the most locally abundant species were also very frequent or occurred in a larger number of plots. there were no significant effects of litter depth, forest canopy openness and forest tree abundance on palm richness. however, in areas where leaf litter was thicker a significant lower number of palm trees occurred. in microsites where proportionally more incident light was reaching the forest understory, due to higher canopy opening, significantly more palm trees were present.
Analysis of floristic composition and structure of a tract of terra firme forest and of an adjacent mangrove stand on the Ajuruteua peninsula in Bragan a, Pará
Maria Milena de Oliveira Abreu,Ulf Mehlig,Raquel do Espírito Santo Aguiar do Nascimento,Moirah Paula Machado de Menezes
Boletim do Museu Paraense Emílio Goeldi : Ciências Naturais , 2006,
Abstract: The current article provides data about floristic composition and forest structure of a terra firme forest fragment and a mangrove stand on Ajuruteua Peninsula, Bragan a, Pará. The fragment is situated next to mangrove forest, without being exposed to tidal inundation. Compared to the mangrove, density and basal area are distinctly higher in terra firme forest (2320.0±736.1/417.7±349.6 indiv..ha-1; 25.2±11.0/9.1±5.3 m2.ha-1 for terra firme and mangrove forest, respectively). Three tree species form the mangrove forest, Rhizophora mangle, being the dominant species. Among the 40 families (71 species) found in terra firme, Arecaceae, Burseraceae (represented exclusively by Protium heptaphyllum) and Simaroubaceae (represented by Simarouba amara reach high importance values. Terra firme forest differs in species composition and complexity from restinga dune forest found in other parts of the peninsula. The high importance of palms in the terra firme forest could indicate influence of man in the past.
Tree communities of white-sand and terra-firme forests of the upper Rio Negro
Stropp, Juliana;Sleen, Peter Van der;Assun??o, Paulo Apóstolo;Silva, Adeilson Lopes da;Steege, Hans Ter;
Acta Amazonica , 2011, DOI: 10.1590/S0044-59672011000400010
Abstract: the high tree diversity and vast extent of amazonian forests challenge our understanding of how tree species abundance and composition varies across this region. information about these parameters, usually obtained from tree inventories plots, is essential for revealing patterns of tree diversity. numerous tree inventories plots have been established in amazonia, yet, tree species composition and diversity of white-sand and terra-firme forests of the upper rio negro still remain poorly understood. here, we present data from eight new one-hectare tree inventories plots established in the upper rio negro; four of which were located in white-sand forests and four in terra-firme forests. overall, we registered 4703 trees > 10 cm of diameter at breast height. these trees belong to 49 families, 215 genera, and 603 species. we found that tree communities of terra-firme and white-sand forests in the upper rio negro significantly differ from each other in their species composition. tree communities of white-sand forests show a higher floristic similarity and lower diversity than those of terra-firme forests. we argue that mechanisms driving differences between tree communities of white-sand and terra-firme forests are related to habitat size, which ultimately influences large-scale and long-term evolutionary processes.
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