Metilação de mercúrio em águas da região amazônica na presença e ausência de macrófitas: experimentos em microcosmos

Pós-graduação em Química - IQ

Distribution, composition and seasonality of aquatic birds in the Nhecolandia sub-region of South Pantanal, Brazil

Despite remarkable significance of Pantanal for the conservation of aquatic birds, the status of their populations, the spatiotemporal patterns of distribution and habitat use and structure of communities are little known. Thus, we studied three aquatic environments (Negro river, bays and salines) from 2007 to 2009 in the Nhecolandia Pantanal to verify the distribution and composition of aquatic birds and also if there is significant seasonal influence on these aspects. We adopted the transect method (288 hours of sampling) and recorded 135 species (7.834 individuals). The Negro river showed the highest diversity, while the salines the lowest. The similarity of aquatic bird communities was higher between bays and salines, followed by Negro river and bays and lower between salines and Negro river. The equidistribution is more variable in the salines and more stable in the Negro river. The environments strongly differ from each other in aquatic bird composition in space (habitat use and distribution) and time (seasonal water fluctuations). The diversity of bird community in the dry season varies significantly in the salines, followed by the bays and more stable in the Negro river. The Negro river, regardless of large annual amplitude of flow, is more seasonally stable since its riparian vegetation is continuous (not isolated) and constant. These aspects provide better conditions to stay all year, contributing to decrease the seasonal nomadic tendencies of aquatic birds. Finally, all these data provide strong arguments to the preservation of all phytophysiognomies in the Nhecolandia sub-region of Pantanal, but with special attention to the salines widely used by many flocks of aquatic birds (mainly in the dry season) and migrant and/or rare species restricted to this habitat.

Determinação in situ de metilmercúrio e mercúrio (II) em sistemas aquáticos nas proximidades de refinarias de petróleo, utilizando a técnica difusão em filmes finos por gradiente de concentração (DGT)

Pós-graduação em Geociências e Meio Ambiente - IGCE

O rio Paraguai no megaleque do Nabileque, sudoeste do Pantanal mato-grossense, MS

The Nabileque fluvial fan is a Quaternary depositional system located along the southwestern border of the Pantanal, covering an area of approximately 9,100 km 2. It is a peculiar alluvial system because it is not associated with inflow from adjacent plateaus. The Nabileque megafan is formed by the Paraguay River at the exit of the Pantanal wetland, coalescing with the Pilcomayo megafan of the Chaco basin. A geomorphological zonation analysis was performed making use of remote sensing data with field verification. Most of the area is a vast alluvial plain made of Pleistocene deposits, whose surface is marked by the presence of an intricate network of distributary paleochannels. Areas blanketed by Pleistocene deposits are dissected by erosional streams and subject to frequent flooding events. The Paraguay River flows in a meander belt constrained by NE fractures associated with the Transbrasiliano Lineament, but deflects towards the SSE after the Negro River confluence composing the system's peripheral drainage. An abandoned meander belt is preserved within a remarkable N-S incised-valley that is interpreted as the ancient Paraguay River course. Processes of avulsion and river capture are suggested to explain the observed changes of the river course. The Nabileque River is an underfit stream within the incised-valley, cutting paleomeanders and point bars of the previous Paraguay River course.

O teatro experimental do negro -: estudo da personagem negra em duas peças encenadas (1947-1951)

Pós-graduação em Artes - IA