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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.
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.
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.
Annual variation of litterfall yield in the channel Furo Grande mangrove stands in Bragan a, Pará  [PDF]
Adriana do Socorro da Costa Gon?alves,Marcus Emanuel Barroncas Fernandes,Muzenilha Lira Carvalho
Boletim do Museu Paraense Emílio Goeldi : Ciências Naturais , 2006,
Abstract: This study was carried out at the Furo Grande, Bragan a-Pará, which is characterized by three types of mangrove stands: one dominated by Rhizophora mangle, another by Avicennia germinans, and a third one being a mixed of both species. The study site presented a litter production of 7.47 t.ha-1.year-1 (year 1) and 7.11 t.ha-1.year-1 (year 2). Although the monthly variation was not statistically significant, this variation indicated a high litter production during the dry season (August to November/2000) and the end of wet season (May to July/2001). Leaves presented an average of 74% of the total production for both years, and it was the component which presented the highest contribution to the total production in all sites during the two years of study, with values that ranged from 65.5% (Site no3 - year 1) to 78.4% (Site no1 - year 2). There was a negative correlation between the litterfall production and the precipitation, indicating a strategy of energetic economy by leaf abscission in the dry season. The litterfall production presented a regular seasonal pattern, which tendency is expected to be repeated in the subsequent years.
Comparison of litterfall yield of two mangrove stands with different structural features on the Bragan a peninsula, Pará  [PDF]
Andrea do Socorro Costa Farias,Marcus Emanuel Barroncas Fernandes,Anneken Reise
Boletim do Museu Paraense Emílio Goeldi : Ciências Naturais , 2006,
Abstract: The estimates of litterfall in the mangal is one of the aspects which must be considered to access the productivity of this ecosystem. Thus, the present work aimed to estimate the total and component rates of the litterfall. Field work was undertaken during an annual cycle, from August, 2000 to July, 2001, in two mangrove areas: a mixed stand (Avicennia germinans, Rhizophora mangle and Laguncularia racemosa) and a dwarf stand (A. germinans). Twelve litter traps were randomly placed in the mixed stand and six in the dwarf one. Trapped material was oven-dried at 70oC, weighed by different components and sorted by species. Results showed that the annual production of litterfal for both Mixed and Dwarf stands was 4.93 and 1.89 t.ha-1.year-1, respectively, representing a very significant difference (ANOVA, F=24.87; gl=23; p<0.01). Leaf represented 70.57% for the mixed stand and 87.58% for the dwarf one, considering the total production. Linear regression analysis of precipitation and litterfall production for both stands, during the annual cycle, demonstrated that litterfall production in these stands was inversely proportional to local precipitation indices, corroborating other studies in the Amazon region. The great difference in the rates of litterfall yield is, certainly, due to the structural pattern of the mangrove stands and the structural development of these stands, which on the other hand, is a result of the local environmental conditions. Finally, the production of leaf and flower in the litterfall are coincident in time, suggesting a strategy in which the mangrove plants, during the changing from dry to wet period, reject leaves to invest more energy in the production of reproductive parts, and try to guarantee the dispersion and the establishment of new individuals.
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.
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.
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.
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