Brasília, Brazil
Brasília, Brazil

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The objective was to evaluate the influence of particle size of the solid ground corncob and sugarcane bagasse, used as filter materials, the efficiency of removing pollutants from swine wastewater (SWW). It was used columns containing the filtering material in three particle sizes (0.84 to 1.19; 1.19 to 2.00 and 2.00 to 2.83 mm). To evaluate the efficiency of the system, the influent and effluent were characterized in relation to the following parameters: biochemical oxygen demand (BOD5), chemical oxygen demand (COD), total solids (TS), total nitrogen (total-N) total phosphorus (total-P), potassium (K), sodium (Na), total copper (total-Cu) and total zinc (total-Zn). Curves were generated by relating the relative concentrations of the variables and the depth of the filtered SWW. The lowest concentrations of BOD in the effluent were obtained, in general, filters made of materials in its largest size; the removals of COD, TS, total-N, total-P were not significantly influenced by the size of the filter materials; the Na and the K had not been retained in the filter materials, in none of the grain sizes studied, however the removal of total-Zn and total-Cu were generally higher in filters consist of filter materials of smaller particle size.

Guimberteau M.,Laboratoire dOceanographie et du Climat Experimentations et Approches Numeriques LOCEAN | Guimberteau M.,Institute Pierre Simon Laplace IPSL | Drapeau G.,Laboratoire dOceanographie et du Climat Experimentations et Approches Numeriques LOCEAN | Drapeau G.,Institute Pierre Simon Laplace IPSL | And 22 more authors.
Hydrology and Earth System Sciences | Year: 2012

The aim of this study is to evaluate the ability of the ORCHIDEE land surface model to simulate streamflows over each sub-basin of the Amazon River basin. For this purpose, simulations are performed with a routing module including the influence of floodplains and swamps on river discharge and validated against on-site hydrological measurements collected within the HYBAM observatory over the 1980-2000 period. When forced by the NCC global meteorological dataset, the initial version of ORCHIDEE shows discrepancies with ORE HYBAM measurements with underestimation by 15% of the annual mean streamflow at Óbidos hydrological station. Consequently, several improvements are incrementally added to the initial simulation in order to reduce those discrepancies. First, values of NCC precipitation are substituted by ORE HYBAM daily in-situ rainfall observations from the meteorological services of Amazonian countries, interpolated over the basin. It highly improves the simulated streamflow over the northern and western parts of the basin, whereas streamflow over southern regions becomes overestimated, probably due to the extension of rainy spots that may be exaggerated by our interpolation method, or to an underestimation of simulated evapotranspiration when compared to flux tower measurements. Second, the initial map of maximal fractions of floodplains and swamps which largely underestimates floodplains areas over the main stem of the Amazon River and over the region of Llanos de Moxos in Bolivia, is substituted by a new one with a better agreement with different estimates over the basin. Simulated monthly water height is consequently better represented in ORCHIDEE when compared to Topex/Poseidon measurements over the main stem of the Amazon. Finally, a calibration of the time constant of the floodplain reservoir is performed to adjust the mean simulated seasonal peak flow at Óbidos in agreement with the observations. © Author(s) 2012.

Filizola N.,Federal University of Amazonas | Latrubesse E.M.,University of Texas at Austin | Fraizy P.,French National Center for Scientific Research | Souza R.,University of the State of Amazonas | And 2 more authors.
Geomorphology | Year: 2014

Floods are fundamental components of Amazon nature and culture. The large flood of 2009, however, opened a new perspective on hazards and disasters in the Amazon basin. More than 238,000 residents from 38 municipalities were affected by floods along the Amazon River and lower reaches of its tributaries. Never before has a flood in the Amazon produced such a dramatic effect on the local population. The magnitude of the disaster suggested it was the largest recorded Amazon flood since the beginning of measurements in 1928 at Óbidos and that it could represent the largest recorded flood on Earth. A complex combination of atmospheric and hydrologic factors made the 2009 Amazon flood the most hazardous. It was the result of large scale and regional climatic events, non-typical mechanisms of flood transmission generating complex inter-relations in time and space between the main system and the tributaries, and recent urban growth of riverine cities without adequate planning. Our measurements at Óbidos, however, indicate that the 2009 flood was the highest recorded Amazon stage, but most likely not the largest water discharge. We propose as well that the magnitude of the Amazon floods at Óbidos has been overestimated for decades and that the available values of flood discharge have been a source of error for a multidisciplinary set of scientists developing climate and environmental modeling. © 2013 Elsevier B.V.

Bielenki Junior C.,University of Sao Paulo | de Souza F.A.O.,Agencia Nacional de Aguas ANA | Mauad F.F.,University of Sao Paulo
Anuario do Instituto de Geociencias | Year: 2015

The application of regionalization methods is one of the most important procedures for the estimation of the streamflow discharge in ungauged rivers catchments and its automation can reduce both processing time and susceptibility to errors. The Environmental Systems Research Institute (ESRI), in cooperation with the Center for Research in Water Resources at University of Texas (CRWR), has developed the ArcHydro toolset, a geospatial data model designed for hydrological models and used to accumulate attributes in the hydrographical net, among other functionalities. The present paper addresses the automation of the low flow index Q95 accumulation in the Doce River Basin by ArcHydro and the application of the regionalization method based on the proportionality of the ratio discharge per unit of drainage area. The effects of the reservoirs operation on water availability were computed automatically in this process and reliable results time savings were achieves. © 2015, Universidade Federal do Rio de Janeiro. All rights reserved.

Soares P.V.,Associacao Corredor Ecologico do Vale do Paraiba | Pereira S.Y.,University of Campinas | Simoes S.J.C.,São Paulo State University | de Paula Bernardes G.,São Paulo State University | And 2 more authors.
Environmental Earth Sciences | Year: 2012

This work describes the methodological approach used for mapping the potential infiltration areas of the Guaratinguetá watershed (160 km2), situated in Southeastern Brazil. The method is considered a qualitative approach, which takes into account thematic maps (geology, pedology, geomorphology, and land use/land cover) and the precipitation spatial distribution. A group of experts in Earth Sciences and Geotechnical Engineering has applied an infiltration potential scale factor that ranges from 5 (highest influence) to 1 (lowest influence). The final infiltration map was produced using several ArcGIS® tools. The results showed that the most suitable (very high) infiltration areas represent only around 7% of the watershed area, which are associated with smooth and gentle hills, fluvial Tertiary sediments and yellow oxisols. However, growing impacts caused by land farming and urban developments require urgent planning for this region. Areas with high to moderate capacity of infiltration represent around 56% of the watershed and are found in the domain of igneous-metamorphic rocks associated with steep hill-slopes and relatively well-preserved forest fragments. This region requires a land-use strategy, such as reforestation programs, in order to increase the infiltration capacity of the watershed. © 2012 Springer-Verlag.

Fan F.M.,Federal University of Rio Grande do Sul | Collischonn W.,Federal University of Rio Grande do Sul | Meller A.,Agencia Nacional de Aguas ANA | Botelho L.C.M.,Companhia Energetica de Minas Gerais CEMIG
Journal of Hydrology | Year: 2014

The present study shows experiments of ensemble forecasting applied to a large tropical river basin, where such forecasting methodologies have many potential applications. The case study is the Três Marias hydroelectric power plant basin (Brazil), on the São Francisco river, where forecast results are particularly important for reservoir operation and downstream flood control. Results showed some benefits in the use of ensembles, particularly for the reservoir inflow on flooding events, and in comparison to the deterministic values given by the control member of the ensemble and by the ensemble mean. The study also discusses the improvements that must be tested and implemented in order to achieve better results, what is particularly important for the smaller basins within the study case. Despite the necessary improvements mentioned, the results suggest that benefits can result from the application of ensemble forecasts for hydropower plants with large basins within the Brazilian energy system. © 2014 Elsevier B.V.

Vasconcellos R.M.,Federal Rural University of Rio de Janeiro | Araujo F.G.,Federal Rural University of Rio de Janeiro | De Sousa Santos J.N.,Federal Rural University of Rio de Janeiro | De Araujo Silva M.,Agencia Nacional de Aguas ANA
Marine Ecology | Year: 2010

Short-term dynamics in juvenile fish assemblage structure were studied to test whether the most abundant species show temporal segregation, in order to assess whether selected environmental variables could predict species groupings, and to examine the stability of sunset-day-sunrise-night differences. Samplings were collected at 3-h intervals over 48 h on a seasonal basis between spring 2005 and winter 2006. Fish species richness and abundance were higher in spring, and the lowest values occurred in winter. Harengula clupeola occurred mainly in spring, whereas Atherinella brasiliensis peaked in summer and autumn. On the other hand, Trachinotus carolinus, Umbrina coroides and Mugil liza were abundant in winter. Although temperature, salinity and dissolved oxygen were not found to have a strong effect on the abundance patterns of most species, they did appear to have a significant influence on assemblage groupings, according to canonical correspondence analysis and Spearman rank correlation. There is no consistency of diel usage patterns by a given species across seasons. The relative abundance differed between the time of day, which differed among the seasons; this further complicates an understanding of the dynamics of an assemblage. Studies of diel changes that pooled the sampling period as day or night can miss important changes that occur in a short time scale, such as a 3-h period. © 2010 Blackwell Verlag GmbH.

Vasconcellos R.M.,Federal Rural University of Rio de Janeiro | Araujo F.G.,Federal Rural University of Rio de Janeiro | De Sousa Santos J.N.,Federal Rural University of Rio de Janeiro | De Araujo Silva M.,Agencia Nacional de Aguas ANA
Journal of the Marine Biological Association of the United Kingdom | Year: 2011

Diel fluctuations in nearshore fish communities were studied at a sandy beach in south-eastern Brazil. A total of 192 samples were performed by beach seines, during 3-hour intervals throughout 48-hour periods, between spring 2005 and winter 2006. Mean biomass and number of species were significantly higher at night, while number of individuals did not differ between day and night. Major disruptions in the fish community occurred during the winter when the assemblages underwent restructuring. Harengula clupeola, Sardinella janeiro, Anchoa lyoleps and Umbrina coroides were the predominant species at night, while Atherinella brasiliensis, Pomatomus saltatrix and Trachinotus carolinus peaked during the day, although significant diel changes in community structure were recorded only in the summer. Biological interactions, behavioural variations and local constraints might explain diel differences in the fish distribution. This study confirms that changes in diel activity in juvenile fish species can differ in similar areas, even for a given species, and the causes of these changes needs to be investigated. © Copyright Marine Biological Association of the United Kingdom 2010.

Remotely sensed evapotranspiration estimations have been used for the calculation of the water balance in hydrographical basins, the definition of aquifer recharge, and the monitoring of drought events. However, there are limitations on local scale applications, such as agricultural management and hydrological modeling that arise from the lack of spatial resolution or the low frequency of image acquisition of current polar satellite constellations. The present article puts forward a procedure to improve the spatial resolution of evapotranspiration estimations obtained from the Moderate Resolution Imaging Spectroradiometer (MODIS), from 1 km to 500 meters resolution. The procedure is based on the disaggregation of the thermal band before estimating of evapotranspiration. Comparison with the ASTER sensor, at 500 meters resolution, indicates a mean error of 25 W m-2 and a correlation coefficient of 0.95.

Mendonca B.C.D.S.E.,Agencia Nacional de Aguas ANA | De Abreu M.M.,Agencia Nacional de Aguas ANA
Water Policy | Year: 2015

Owing to the increase in urban populations, there has also been an increased incidence of critical events, especially those related to floods and landslides. Since the implementation of the National Civil Defense System in Brazil, a focus on disaster management is no longer the answer when assisting those affected; instead, the answer has become managing disaster risk, in addition to the response, including prevention and minimizing the effects of the critical event. This paper highlights the actions for modernization and expansion of the hydrological monitoring network, in particular the alert network, the completion of an atlas of vulnerability to floods and the deployment of Situation Rooms in the states, with a view to strengthening the role of these bodies in disaster risk management, and enabling greater responsiveness to these events and the use of the information gathered as a water resources management tool, allowing for better use of public resources. © IWA Publishing 2015.

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