Conquering Brazil: the invasion by the exotic gekkonid lizard Hemidactylus mabouia (Squamata) in Brazilian natural environments

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Changes in abiotic characteristics of water in the Paranapanema River and three lateral lagoons at mouth zone of the Jurumirim Reservoir during the flood period, São Paulo, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Structural description of humic substances from subtropical coastal environments using elemental analysis, FT-IR and C-13-solid state NMR data

Elemental composition and spectroscopic properties (FT-IR and CP/MAS C-13-NMR) of sedimentary humic substances (HS) from aquatic subtropical environments (a lake, an estuary and two marine sites) are investigated. Humic acids (HA) are relatively richer in nitrogen and in aliphatic chains than fulvic acids (FA) from the same sediments. Conversely, FA are richer in carboxylic groups and in ring polysaccharides than HA. Nitrogen is mostly present as amide groups and for lake and marine HS the FT-IR peaks around 1640 cm(-1) and 1540 cm(-1) identify polypeptides. Estuarine HS exhibit mixed continental-marine influences, these being highly influenced by site location. Overall, the data suggest that aquatic and mixed HS are more aliphatic than has been proposed in current models and also that amide linkages form an important part of their structural configuration.

The Role of Mucus in Mytella falcata (Orbigny 1842) Gills from Polluted Environments

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

The significance of changes in Mytella falcata (Orbigny, 1842) gill filaments chronically exposed to polluted environments

The impact of pollutants in an organism can be observed by changes in functional complexity at different levels. Bivalve gills are suitable for histopathological analysis because of their structure and function. This study aimed at examining the morphology of Mytella falcata gill filaments from three sites in the Santos estuary (São Paulo, Brazil) with different levels of environmental degradation to identify possible changes in gill structure and discuss the significance of these alterations. For this purpose, histological, histochemical and ultrastructural techniques were used. The filaments of animals from site A (less impacted site) were intact, while in sites B and C, pathological changes were observed, such as: detachment of the epithelium in the intermediate zone, morphological changes of this epithelium, inflammatory process, increase in the number of mucous cells and cell turnover processes. These results suggest that the related changes are an attempt to prevent the entrance of pollutants through gill filaments into the entire organism and that cell turnover is the final way to compensate cell injury. (C) 2008 Elsevier Ltd. All rights reserved

Effects of exposition to polluted environments on blood cells of the fish Prochilodus lineatus

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Evidence of higher photosynthetic plasticity in the early successional Guazuma ulmifolia Lam. compared to the late successional Hymenaea courbaril L. grown in contrasting light environments

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Reproductive seasonality of fishes from a lotic stretch of the Grande River, high Paraná river basin, Brazil

Foi investigada a correlação entre nível hidrológico, pluviosidade e temperatura e reprodução de peixes num trecho lótico do rio Grande, abaixo da barragem de Volta Grande. Para a captura, realizada com redes de espera, foram feitas seis amostragens bimestrais de abril de 1998 a fevereiro de 1999. As gônadas foram classificadas de acordo com o estádio de maturação e aquelas maduras ou esgotadas foram correlacionadas com as variáveis ambientais. A maioria das espécies apresentou reprodução sazonal, entre outubro e fevereiro. A freqüência relativa bimestral de gônadas maduras ou esgotadas de todos os exemplares agrupados foi correlacionada significativamente com pluviosidade (Spearman r = 0,94, p = 0,005) e temperatura do ar (r = 0,84, p = 0,036), mostrando a importância destes fatores no controle do ciclo reprodutivo dos peixes. Devido à barragem, o nível hidrológico pouco variou e não foi encontrada correlação significativa entre reprodução e nível hidrológico (r = -0,43, p = 0,396).

Morphological, morphometrical and ultrastructural characterization of Phrynops geoffroanus' (Testudines: Chelidae) blood cells, in different environments

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Statistics and kinetics of single-molecule electron transfer dynamics in complex environments: A simulation model study

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Evaluation of seasonal dynamics and bioindication potential of macroalgal communities in a polluted tropical stream

Macroalgal communities and environmental variables were analyzed seasonally along a polluted tropical stream in São Paulo State, Brazil, We aimed to improve the knowledge of tropical macroalgal communities, to study the longitudinal and seasonal dynamics of these communities in influenced environments, to evaluate the relationship of algal frequency and abundance with selected environmental variables, and to look for potential macroalgal species indicators. The seasonal abundance pattern was similar to natural or low influenced systems and was mainly determined by rainfall regime. However, community composition was closely related to some chemical water pollution indicators, such as phosphorus and nitrogen compounds. Some species are suggested as potential indicators of organic pollution (e.g. Oscillatoria ornata, Stigeoclonium helveticum and Schizomeris leibleinii), but more detailed studies have to be developed to determine the tolerance limits of these species. on the basis of our results and literature data, the use of occurrence of Oscillatoriales in relation to other orders of Cyanoprokaryota is suggested to be a good indicator of organic pollution in tropical lotic ecosystems.

Patterns of spatial distribution in macroalgal communities from tropical lotic ecosystems

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Limnogeology in Brazil's "forgotten wilderness": a synthesis from the large floodplain lakes of the Pantanal

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)