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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.
Dieta de Micoureus demerarae (Thomas) (Mammalia, Didelphidae) associada às florestas contíguas de mangue e terra firme em Bragan?a, Pará, Brasil
Fernandes, Marcus E. B.;Andrade, Fernanda A. G.;Silva Júnior, José de S. e;
Revista Brasileira de Zoologia , 2006, DOI: 10.1590/S0101-81752006000400015
Abstract: the diet of micoureus demerarae (thomas, 1905) was studied in mangrove and terra firme stands by using stomachal and faecal samples. the number of captured individuals was inversely proportional to availability of fruits and insects, being coleoptera and hemiptera the most consumed arthropod orders and passifloraceae and arecaceae the most ingested fruits. thus, either fruits variability or their high yield during the dry season seem to explain the increase of captured animals in the terra firme stands, where they originally come from. the food items suggest that this species has an omnivorous diet, independently of the seasonality or distribution of available resources.
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.
Parametros demográficos de Micoureus demerarae (Didelphidae, Marsupialia) em áreas contíguas de manguezal e terra firme, Bragan?a, Pará, Brasil
Andrade, Fernanda A. G.;Fernandes, Marcus E. B.;Brito, Stélio A. C.;
Revista Brasileira de Zoologia , 2007, DOI: 10.1590/S0101-81752007000200002
Abstract: this study investigated some aspects of the population dynamics of micoureus demerarae (thomas, 1905), such as: density, recruitment, and survivorship in two contiguous ecosystems, mangal and terra firme at the fazenda das salinas in the northeast of the state of pará. one transect in each system was used for fieldwork. data collection was carried out from november 2002 to september 2003. the following population parameters were estimated: density, recruitment, and survivorship. the results defined an open population with an even distribution for individuals from mangal and a clumped one for individuals from terra firme, and the evident seasonality with higher proportion of males in the terra firme. the reproductive period was the most important parameter to the population fluctuation in the beginning of the dry season. the environmental impacts over the population dynamics parameters of m. demerarae seem to be determinant for the maintenance of these populations.
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.
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.
Integrating regional and continental 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 Discussions , 2009,
Abstract: We contrast regional and continental-scale comparisons of the floristic composition of terra firme forest in South Amazonia, using 55 plots across Amazonia and a subset of 30 plots from northern Peru and Ecuador. Firstly, we examine the floristic patterns using both genus- or species-level data and find that the species-level analysis more clearly distinguishes different plot clusters. Secondly, we compare the patterns and causes of floristic differences at regional and continental scales. At a continental scale, ordination analysis shows that species of Lecythidaceae and Sapotaceae are gradually replaced by species of Arecaceae and Myristicaceae from eastern to western Amazonia. These floristic gradients are correlated with gradients in soil fertility and to dry season length, similar to previous studies. At a regional scale, similar patterns are found within north-western Amazonia, where differences in soil fertility distinguish plots where species of Lecythidaceae, characteristic of poor soils, are gradually replaced by species of Myristicaceae on richer soils. The main coordinate of this regional-scale ordination correlates mainly with concentrations of available calcium and magnesium. Thirdly, we ask at a regional scale within north-western Amazonia, whether soil fertility or other distance dependent processes are more important for determining variation in floristic composition. A Mantel test indicates that both soils and geographical distance have a similar and significant role in determining floristic similarity across this region. 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 dependent on a range of processes that include both habitat specialisation related to edaphic conditions and other distance-dependent processes. 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 from north-western Amazonia.
Aspectos florísticos e ecológicos de grandes lianas em três ambientes florestais de terra firme na Amaz?nia Central
Oliveira, Arlem Nascimento de;Amaral, Iêda Le?o do;Ramos, Michele Braule Pinto;Formiga, Kianny Martins;
Acta Amazonica , 2008, DOI: 10.1590/S0044-59672008000300005
Abstract: lianas, or woody vines, are a significant component of most tropical forests. to investigate the floristic and ecological aspects of large lianas from three forest environments on terra firme in central amazonia (2o35' s and 60o12' w) 20 plots of 50 m x 10 m were placed in each of the forest environments (plateau forest, slope forest and sandbank forest) and all lianas with diameter at breast height (dbh) > 10 cm were measured. in terra firme plateau forest 17 individuals were sampled, belonging to nine families, ten genera and thirteen species. fabaceae and combretaceae were the most species-rich families, representing together over 46% of all samples. the species with highest importance values (iv) were doliocarpus brevipedicellatus garcke (iv = 58.21) and abuta candollei triana & planch. (iv = 33.28). a total of twelve individuals, belonging to four families, four genera and eight species were registered in terra firme slope forest. in this forest environment, caesalpiniaceae was the most species-rich family, with 38% of the identified species. abuta rufescens aubl. (iv = 102.08) and bauhinia alata ducke (iv = 65.80) were the liana species with highest importance values. in terra firme sandbank forest four individuals were registered, belonging to four families, four genera and four liana species. in the three forest environments, seven liana individuals reached over 20 cm of dbh. the floristic similarity among terra firme forest environment was relatively low for species, with the least floristic dissimilarity between terra firme slope forest and sandbank forest (is = 0.17). in this study, according to shannon-wiener, simpson's and fisher's alpha diversity indices, the terra firme plateau forest was more diversified in large liana species.
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