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Tipo de item:Pessoa, Tipo de item:Pessoa, Tipo de item:Publicação, Dissertação Avaliação das correções do atraso zenital troposférico nas medições efetuadas por radares altimétricos na região amazônica(Instituto Nacional de Pesquisas da Amazônia - INPA, 2015)Oliveira, Robson Azevedo deCurrently, the major errors in altimetry measure by sensors onboard satellites have been attributed to the propagation of the signal trough the dynamic atmosphere,which is divided between the ionosphere and the electrically neutral layer. This study aimed to evaluate the effects of the electrically neutral layer, consisting of troposphere, tropopause, stratosphere and part of stratopause, on signal of three satellites: ENVISAT, SARAL and Jason-2. The effect of tropospheric refraction can be modeled using in situ data from weather station, separating it into two parts: the delay due to the effect of dry gases and the delay due to the effect of water vapor, DTC and WTC, respectively. These corrections are considered as the most relevant ones, related to the study of inland waters. Errors in the continuity between correction data supplied by ECMWF model for the same orbit satellites have been detected, at some stations, indicating a non-homogeneity in corrections. Limitations in capturing the seasonality of WTC data in humid regions of the Amazon, featuring better results in regions with greater seasonal variation of moisture, aiming for the need for other sources of data, such as radiosondes for a better representation of the moisture profile of the atmosphere, by the meteorological model Saastamoinein have been observed. In addition, find mistakes that should not still in the current version of the GDR data were also observed in some sites studied in the Amazon. This fact stresses that it is need to pay more attention to the standardization of the data used in the various altimetry products.Tipo de item:Publicação, Dissertação Fontes autotróficas de energia e dieta de Characiformes juvenis em herbáceas aquáticas do rio Solimões/Amazonas(Instituto Nacional de Pesquisas da Amazônia - INPA, 2010)Soares, Gilcideya SilvaAquatic macrophyte communities are important environments in aquatic ecosystems in that they produce a great quantity of organic material and are also indispensable for the initial development of many fish species particularly the migrating Characiforms. In order to evaluate this a total of 1181 Triportheus angulatus, Brycon amazonicus, Semaprochilodus insignis and Mylossoma duriventre specimens captured among the macrophyte stands were examined. They varied from 15 to 60mm standard length. Stomach contents and carbon and nitrogen isotopes of these specimens were analysed in order to determine their principle prey, their energy sources and their position in the food chain. In the smaller fish links between the producers were principally insects and zooplankton. As they grew the four species incorporated different items in their diet in different manners. Based on the carbon isotope analyses it was possible to confirm that the C3 plants are the most important plant group for these young fish. It was observed that in this development stage the Characiforms alternate their energy sources between more and less negative as they grow. The greatest difference in trophic position was observed in the juveniles of S. insignis whose diet consisted principally of detritus. The other species occupied positions between the first and second trophic level. A combination of the results obtained here shows that herbaceous aquatic macrophytes in the floodplain of the Solimões/River are essential for the development of fish species in the first stages of their lives.Tipo de item:Publicação, Dissertação Variação ao longo de um ano hidrológico da diversidade, estrutura trófica e intensidade reprodutiva da ictiofauna de fundo no lago Catalão, Amazônia Central(Instituto Nacional de Pesquisas da Amazônia - INPA, 2012)Farago, Thatyla Luana BeckThis study evaluated the influence of the hydrological cycle on the taxonomical composition, trophic structure and intensity of reproductive of the benthic fish fauna of Catalão floodplain lake. We sought to determine whether the benthic fish assemblage is an extension of the pelagic assembly or if it is a distinct one. The material was collected with the aid of a bottom trawl-net and a set of gillnets between June 2010 and August 2011. 3899 specimen were collected, belonging to five orders and 110 species, the order Siluriformes was the most diverse (47%) and Characiformes the most abundant (39%). The depth of the floodplain lake and the limnological characteristics of each period influenced the dynamics of the assembly. During most part of the water cycle there are two different assemblies, both in number of species and specimen. But during the dry season these assemblies are mixed and it is difficult to separate them. The variation in water level influence the consumption of food items, however plankton and detritus were the most consumed. Seven trophic categories were established, with seasonal difference in the values of total weight and richness. 34% of the species changed the trophic category, revealing a high trophic adaptability of the species that make up this assembly. The low number of species in reproduction and the value found for the Reproductive Intensity Index (1.28) suggest that the lake Catalão is not a breeding site but a growth and feeding site for this benthic fish fauna.