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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.
Structure and composition of the ground-herb community in a terra-firme Central Amazonian forest
Costa, Flávia Regina Capellotto;
Acta Amazonica , 2004, DOI: 10.1590/S0044-59672004000100007
Abstract: the herb community of tropical forests is very little known, with few studies addressing its structure quantitatively. even with this scarce body of information, it is clear that the ground herbs are a rich group, comprising 14 to 40% of the species found in total species counts in tropical forests. the present study had the objective of increasing the knowledge about the structure and composition of the ground-herb community and to compare the sites for which there are similar studies. the study was conducted in a tropical non-inundated and evergreen forest 90 km north of manaus, am. ground herbs were surveyed in 22 transects of 40 m2, distributed in five plots of 4 ha. the inventoried community was composed of 35 species, distributed in 24 genera and 18 families. angiosperms were represented by 8 families and pteridophytes by 10 families. marantaceae (12 sp) and cyperaceae (4 sp) were the richest families. marantaceae and poaceae were the families with greatest abundance and cover. marantaceae, poaceae, heliconiaceae and pteridophytes summed 96% of total herb cover, and therefore were responsible for almost all the cover of the community. the 10 most important species had 83.7% of the individuals. in general, the most abundant species were also the most frequent. richness per transect varied from 7 to 19 species, and abundance varied from 30 to 114 individuals. the community structure was quite similar to 3 other sites in south america and one site in asia.
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.
Vertical stratification of bat assemblages in flooded and unflooded Amazonian forests  [cached]
Maria Jo?o Ramos PEREIRA, Jo?o Tiago MARQUES, Jorge M. PALMEIRIM
Current Zoology , 2010,
Abstract: Tropical rainforests usually have multiple strata that results in a vertical stratification of ecological opportunities for animals. We investigated if this stratification influences the way bats use the vertical space in flooded and unflooded forests of the Central Amazon. Using mist-nets set in the canopy (17 to 35 m high) and in the understorey (0 to 3 m high) we sampled four sites in upland unflooded forests (terra firme), three in forests seasonally flooded by nutrient-rich water (várzea), and three in forests seasonally flooded by nutrient-poor water (igapó). Using rarefaction curves we found that species richness in the understorey and canopy were very similar. An ordination analysis clearly separated the bat assemblages of the canopy from those of the understorey in both flooded and unflooded habitats. Gleaning carnivores were clearly associated with the understorey, whereas frugivores were abundant in both strata. Of the frugivores, Carollinae and some Stenodermatinae were understorey specialists, but several Stenodermatinae mostly used the canopy. The first group mainly includes species that, in general, feed on fruits of understorey shrubs, whereas the second group feed on figs and other canopy fruits. We conclude that vertical stratification in bat communities occurs even within forests with lower canopy heights, such as Amazonian seasonally flooded forests, and that the vertical distribution of bat species is closely related to their diet and foraging behaviour [Current Zoology 56 (4): 469–478, 2010].
Four species of the new Amazonian sharpshooter Daedaloscarta gen. nov. (Insecta: Hemiptera: Cicadellidae)  [cached]
Rodney R. Cavichioli,Daniela M. Takiya
Zoologia (Curitiba) , 2012,
Abstract: Four new species, Daedaloscarta erwini sp. nov. (Peru: Loreto), D. maculata sp. nov. (Brazil: Amazonas), D. mene sp. nov. (Ecuador: Orellana), and D. redacta sp. nov. (Brazil: Amazonas) are described and placed in the new genus Daedaloscarta gen. nov. Species of the new genus can be readily distinguished from other Cicadellini genera by their: (1) dark brown to black dorsal coloration with contrasting large ivory spots; (2) crown produced and round anteriorly (Figs 1-8); (3) pronotum narrower than transocular width of head, with lateral margins parallel; (4) male pygofer with pair of acute finger-like processes arising at dorsal margin directed inwardly and ventrally; (5) subgenital plates with apical two-thirds very slender; (6) aedeagus very large with shaft elongate, with an unpaired basidorsal, elongate bifurcate basiventral, and paired retrorse lateral processes at midlength of shaft; and (7) paraphyses bifurcate and slender. All known specimens are associated with terra firme or flooded Amazonian forests and were collected by light trapping or insecticidal fogging.
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.
Influence of drainage status on soil and water chemistry, litter decomposition and soil respiration in central Amazonian forests on sandy soils  [cached]
Fabrício Berton Zanchi,Maarten Johannes Waterloo,Albertus Johannes Dolman,Margriet Groenendijk
Ambiente e água : An Interdisciplinary Journal of Applied Science , 2011,
Abstract: Central Amazonian rainforest landscape supports a mosaic of tall terra firme rainforest and ecotone campinarana, riparian and campina forests, reflecting topography-induced variations in soil, nutrient and drainage conditions. Spatial and temporal variations in litter decomposition, soil and groundwater chemistry and soil CO2 respiration were studied in forests on sandy soils, whereas drought sensitivity of poorly-drained valley soils was investigated in an artificial drainage experiment. Slightly changes in litter decomposition or water chemistry were observed as a consequence of artificial drainage. Riparian plots did experience higher litter decomposition rates than campina forest. In response to a permanent lowering of the groundwater level from 0.1 m to 0.3 m depth in the drainage plot, topsoil carbon and nitrogen contents decreased substantially. Soil CO2 respiration decreased from 3.7±0.6 μmol m-2 s-1 before drainage to 2.5±0.2 and 0.8±0.1 μmol m-2 s-1 eight and 11 months after drainage, respectively. Soil respiration in the control plot remained constant at 3.7±0.6 μmol m-2 s-1. The above suggests that more frequent droughts may affect topsoil carbon and nitrogen content and soil respiration rates in the riparian ecosystem, and may induce a transition to less diverse campinarana or short-statured campina forest that covers areas with strongly-leached sandy soil.
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.
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