Repositório RCAAP

Abstract This paper develops a model to characterize the demand for domestic water based on its end users' usage habits. The use of individual residential appliances (bathroom sink, toilet, shower, bath, etc.) is interpreted using a probabilistic approach. The paper also applies the model to the distribution network of the municipality of Sparanise, a small city in the province of Caserta, Italy. The results of this application are compared to the real output of the city's actual water reservoir. Flow variability during the day was successfully modelled. A comparison of the simulated and recorded data on a daily level indicates the proper adjustment of the volume distribution; the peak flow rates were also comparable. The model could be a useful tool for analyzing domestic water consumption, especially in the design and management of water distribution networks. Use of the model would particularly aid the Integrated Urban Water Management Operator both in optimizing the operating pressures in the various districts’ networks and in predicting domestic water consumption when drafting its water balance documents.

Abstract Urbanization modifies the heat balance in urban areas and has negative effects on landscape, aesthetics, energy efficiency, human health and the inhabitants’ quality of life. This work evaluated future scenarios of bioclimatic conditions for João Pessoa, a humid tropical city in Northeast Brazil. The scenarios were determined based on trends in air temperature, relative humidity and wind speed for the time period from 1968 to 2015. The study was performed for two distinct periods of three months each (dry and wet seasons) using data from weather stations equipped with thermo-hygrometers and cup anemometers located in nine representative areas of the city. Trends in air temperature, relative humidity, wind speed, and effective temperature index (ET index) time series were evaluated using the Mann-Kendall test. Results indicated that the air temperature showed an increasing trend of 0.34°C /decade, whereas the relative humidity showed a decreasing trend of 0.49%/decade and the wind speed values ranged from 1.3 ms-1 to 3.80 ms-1. These trends are statistically significant according to the Mann-Kendall test (p<0.05). The air temperature increased between the 1980s and 2010s, which corresponds to a period of rapid urbanization of the city. Future environmental conditions in João Pessoa will be determined in accordance with the urbanization processes.

Abstract This study analyzed the relative cost of charging for water use with respect to water users' production costs in the Grande River Basin, located in the Brazilian Cerrado, considering the principal charging methods existing in Brazil. The study was developed based on: the rights of use grant data surveys pertaining to water resources and the classification of bodies of water into usage classes; a simulation of charging for water use through various methods; and an analysis of the relative cost of charges on the production cost of the water users. The charging methods used by the following were studied: the Committee of the Basin of River Paraíba do Sul (CEIVAP), the Committee of Basins of Piracicaba, Capivari and Jundiaí Rivers (PCJ), the São Francisco River Basin Committee (CBHSF) and the Doce River Basin Committee (CBH-DOCE). The study verified that irrigated agriculture is the sector that uses the most water, representing 46.4% of the outflow granted in the basin. Considering the different charging methods, the collection in the basin of the Grande River potentially allows for investments of US$ 1.2 million (PCJ), US$ 920,000 (CEIVAP), US$ 426,000 (CBH-DOCE), or US$ 297,000 (CBHSF) in this region, leading to average relative costs of 0.68% (irrigation), 0.28% (human) and 0.08% (industry). For this reason, there is the possibility of implanting charges for water use in the Grande River Basin, with either the CEIVAP's or PCJ's method appearing to be the most suitable, given that the parameters of these mechanisms are in line with existing activities in the basin.

Abstract This research determined the efficiency of removal of chemical oxygen demand (COD) by an electrocoagulation process. An electrocoagulation reactor with aluminum and iron electrodes was used to treat water from the treatment plant of the Research Center for Wastewater Treatment and Hazardous Waste. The COD removal percentage was a response variable for the experimental factorial design. The factors influencing the process were current intensity, treatment time, and pH. The best results in the percentage of removal of the COD were very similar to that obtained at a pH of 8.2 and 7, with values of 83% and 84%, respectively, with a current intensity of 7 A and a treatment time of 15 min. However, at 5 A and 10 min, values that exceed 80% removal were obtained. Statistical analysis indicates that only current intensity and time were significant for the response variable. Electrocoagulation is a viable process for the treatment of this type of effluent, in addition to being more versatile compared with biological processes.

Abstract This study investigated of the potential value of the integration of the coagulation/flocculation, Advanced Oxidation Processes (AOP) (Fenton reagent) and slow sand filtration technologies, with the aim of treating laboratory wastewater. The treatment system was designed in laboratory scale through coagulation/flocculation. It involved the use of Jar Test equipment with a sequence of two rotational phases: fast mixes to 300 rpm for 20 seconds and slow mixes to 30 rpm for 6 minutes and 10 seconds, with the addition of anionic polymer and sedimentation for 60 minutes at ambient temperature. In the treatment via Fenton reagent, two rotational phases were used: rapid mixing at 300 rpm for 20 seconds with the addition of iron (Fe2+) and slow mixing at 30 rpm for 6 minutes and 10 seconds with the addition of hydrogen peroxide, followed by 60 minutes of sedimentation at ambient temperature. A cylindrical tank of polyvinyl chloride, sands and non-woven synthetic fabrics were used in the slow filtration. The filtration rate adopted was 3 m3 m-2 d-1 with a hydraulic retention time of 264 minutes. The best concentrations of chemical reagents used in the treatments were: 0.80 mg L-1 of polymeric anionic, 200.00 mg L-1 of H2O2 and 13.00 mg L-1 of total soluble iron. The integration of the treatment technologies made it possible to achieve a removal rate of 75.27% of COD and 94.12% of total phenols. Furthermore, the conjugation of the processes allowed the removal of 87.58% of TOC.

Resumo Os incêndios e as queimadas que ocorrem no Pantanal causam grandes prejuízos à fauna e flora locais. A previsão de eventos é de grande importância por possibilitar que as catástrofes nesse ecossistema sejam amenizadas ou, até mesmo evitadas. Este estudo teve como objetivo avaliar as ocorrências de queimadas e incêndios no Pantanal Sul-Mato-Grossense, associadas às variáveis meteorológicas e realizar uma modelagem de previsão a partir de técnicas de análise multivariada de dados. As variáveis ambientais envolvidas nesse processo foram extraídas da base de dados do Centro de Previsão de Tempo e Estudos Climáticos do Instituto Nacional de Pesquisas Espaciais (INPE) e do banco de dados meteorológicos para ensino e pesquisa do Instituto Nacional de Meteorologia (INMET). Foram observadas que a temperatura, umidade relativa e radiação solar, possuem um relacionamento estreito com a ocorrência dos focos e as correlações resultantes foram satisfatórias para a aplicação das modelagens de previsão. A técnica de Regressão Linear Múltipla apresentou 41% de ajustamento e a técnica de Análise Auto-regressiva Integrada de Médias Móveis apresentou ajustamento de 66,5% e desempenho geral de 68,4%, tornando-a a metodologia mais recomendada para a previsão.

Resumo O objetivo neste trabalho foi analisar a dinâmica temporal da pegada hídrica de oito cultivares de soja, plantadas na região do Oeste do Pará. Foram utilizados dados meteorológicos correspondentes ao período de 2009 a 2014 para calcular as taxas evapotranspiratórias da cultura. Como a Pegada Hídrica é subdividida em verde, azul e cinza e, na região os cultivos não são irrigados contabilizou-se apenas a verde e a cinza. A PHverde foi estimada considerando-se o total de água consumida durante o ciclo de cada cultivar. A PHcinza foi avaliada utilizando como fator contaminante em corpos hídricos o composto nitrato que está presente nos fertilizantes nitrogenados, conforme as concentrações aceitáveis pelo CONAMA 357/2005. Considerou-se dois valores para as doses de N, sendo 30 kg ha-1 com base na adubação descrita na literatura, bem como o N existente nas formulações (2:20:20) dos adubos vendidos na região, sendo 2 kg ha-1 o máximo utilizado na adubação de cobertura. Entre as oito cultivares analisadas, em termos de indicador de baixa pegada hídrica, as cultivares BRS 278 RR; BRS 325 RR e BRS 333 RR foram as mais expressivas no polo de grãos no oeste do Pará, evidenciando o uso eficiente da água disponível em todos os anos/safras analisados. A soja produzida no oeste do Pará possui baixa pegada hídrica cinza. Todavia, os valores de redução da produtividade em anos safra na região comprometem a pegada hídrica verde pela sojicultura na região, evidenciando que esse indicador deve ser analisado considerando as especificidades de cada cultivar de soja. O valor da pegada hídrica total estimada neste trabalho foi inferior aos obtidos na literatura, reforçando a importância de estimar a Pegada Hídrica (PH) como indicador de uso consuntivo de água em cultivos de grãos na Amazônia.

Abstract Aquatic environmental pollution due to negative human activities remains a major problem. Bioindicators that primarily describe the total concentration of the respective pollutant are very useful tools to aid in the chemical analysis of water in order to obtain knowledge about the levels of pollutants in the environment. This study therefore used Electron Spin Resonance Spectroscopy (ESR) to detect the presence of transition metals (copper, iron and manganese) and possible radicals present in samples of Neoechinorhynchus curemai and its host tissues Prochilodus lineatus, as well in water and sediment of the Batalha River, at the same sample site where fish were collected. Spectral analysis of samples showed the presence of three metals (Cu2+, Fe3+ and Mn2+), in addition to nitric oxide (NO) and humic acid (HA). Quantification of the elements in the samples was possible only for Cu detected in the spectrum of parasites, which was equivalent to 2 ppm. ESR proved to be efficient in the detection of transition-metal ions (Cu2+, Fe3+ and Mn2+), in addition to NO and HA. However, the low concentration values of these compounds in P. lineatus tissues (liver, muscle and intestine) and in the water and sediment samples collected did not allow their quantification, as they were below the limit of detection. It can be concluded that N. curemai had the capacity to accumulate these ions, especially copper.

Abstract Hydrological simulation models have proven to be an important tool for managing and planning water resources, enabling the assessment of the impacts of rainfall on surface runoff and soil moisture. This work therefore aimed to apply the SWAT model for the analysis of hydrological processes in the Experimental Basin of the Jatobá Stream, in the semiarid region of the State of Pernambuco, Brazil, considering the calibration and validation of the model from streamflow and soil moisture data. Moreover, the study investigated hydrological effectiveness in a recovery scenario in areas of higher topographic elevation of the arborescent Caatinga and the behavior of the hydrological components under an agricultural expansion scenario. Events which occured between 2009 and 2010 were used to calibrate and validate streamflow and soil moisture data. The calibration and validation of streamflow exhibited efficiency coefficients (NSE) of 0.58 and 0.42, respectively, and 0.53 and 0.46 for soil moisture. The adjustment of the parameters was considered adequate for representing streamflow recession periods. It was also verified that the alternative process of calibration and validation with soil moisture reduced uncertainty. Regeneration of the vegetative cover over 21% of the hilltop areas of arborescent Caatinga led to a significant increase in percolation (42%) and a decrease of 34% in soil moisture (due to water consumption by plants), thus contributing to the recovery of headwaters, increasing resilience to water scarcity. On the other hand, the 38% expansion of agriculture caused an increase of 11% in surface runoff and, consequently, an increase of 10% in soil moisture.

Abstract The quality of drinking water and its health implications for school children were examined at schools in the Santarém region, Amazon, Brazil. In this region, the population is fully supplied by groundwater from the voluminous Alter do Chão aquifer. Drinking water samples from three schools in Santarem city and from one school at the rural Mojuí dos Campos town were subjected to microbiological and physicochemical compositional analyses. The health risk of human exposure to chemical compounds through water intake was also evaluated. The results indicated that most water samples were contaminated with total coliform and with E. coli, which could cause serious intestinal disorders for school children. Drinking water was acidic and most of the chemical element concentrations were within Brazilian water potability recommended levels. One exception was the high aluminium content in schools from Santarem served by shallower wells, suggesting that further epidemiological studies are necessary and the monitoring of exposed school children should not be discarded. Elevated nitrate concentrations were also noted in schools from Santarém with shallower wells, indicating lack of sanitation and the importance of periodic monitoring of drinking water to prevent adverse health effects. Quantification of human health risk indicated a hazard in schools served by shallower wells, with aluminium as the main pollutant, followed by nitrate. The results showed that most drinking water quality parameters are in accordance with Brazilian legislation. However, microbiological contamination, water acidity, aluminium and nitrate concentrations must be taken into consideration for local governments in order to prevent related diseases among school children.

Abstract This work applied the coupled horizontal two-dimensional hydrodynamic circulation model (2DH) and the vertically integrated water quality model for non-conservative and passive scalars to the Rio Verde reservoir in the state of Paraná, Brazil, to simulate flow, temperature and water quality parameters. The water quality model uses the same spatial grid applied for the hydrodynamics model. Flow velocities and turbulence coefficients previously defined in the hydrodynamics model can be used directly in the water quality model. Modeling results were compared to field data for a period of 308 days, from February 27th 2010 and December 31th 2010. Field data included water and air temperature, wind, relative humidity, radiation, discharges and concentration values of some substances in the tributaries of the reservoir. The results indicated that hydrodynamic circulation and, consequently, horizontal transport, are strongly dependent on the wind. Inflows/outflows generated a localized circulation. The results for the temperature and dissolved oxygen concentration were compared with field measures and a satisfactory consistency was achieved. Despite the errors associated with boundary conditions, the models demonstrated their potential to adequately simulate the data set collected from the reservoir.

Abstract This study evaluated the toxicity of effluent generated in a furniture industry spray booth, before and after treatment in a system composed of an anaerobic sequencing batch (ASBR) followed by an aerobic sequencing batch reactor (SBR). The toxicity tests were carried out with raw (with and without dilutions) and treated effluent to evaluate the toxic potential using Allium cepa and Lactuca sativa as bioindicators. The toxicity tests, using Allium cepa and Lactuca sativa, indicated that the anaerobic-aerobic treatment performed was efficient to reduce the toxicity of the paint booth effluent. The raw effluent, undiluted and diluted (at 1:10; 1:8 and 1:6 dilutions), showed toxic effect on the root growth of Allium cepa, as it inhibited root growth by 100%. In the tests with Lactuca sativa seeds, there was partial inhibition, between 44% and 63%, for 1:10 and 1:8 dilutions, but for the 1: 6 dilution and without dilution of effluent the inhibition was 100%. The treated effluent, in an ASBR followed by an SBR, presented a small percentage of inhibition for tests with Allium cepa (13%) and Lactuca sativa seeds (4%). The effluent treated by the anaerobic system followed by aerobic presented low toxicity without generating lethal or sub-lethal effects to the test organisms, which indicates the efficiency of the treatment process.

Abstract The effects of the absence of nitrogen and phosphorus on AA media and three different light intensities (100% Light, 60.0 ± 2.7 μmol m-2 s-1, 50% Light, 30.0 ± 2.7 μmol m-2 s-1, and 13.5% Light, 8.1 ± 2.7 μmol m-2 s-1) on cell production and synthesis of heterocytes and akinetes were determined in a strain of Nostoc paludosum. In the experiment concerning the absence of nutrients, significant variations were observed between the control group and the groups with absence of nutrients, especially in cell numbers and in synthesis of heterocytes and akinetes. The absence of nitrogen boosted the formation of heterocytes and the absence of phosphorus produced the most akinetes. As for the different light conditions, the growth curves determined for each treatment showed that cell synthesis is slightly affected by the reduction of illuminance. The different light intensities are capable of reducing the maximum growth rates of Nostoc paludosum, with 13.5% light restriction being the most effective on limiting the cell growth rate and inducing the formation of akinetes. The synthesis of heterocyte does not seem directly correlated to light intensity, being better explained by nutritional factors. The data found contributes to the understanding of some of the factors involving growth and synthesis of special structures in Nostoc paludosum.

Abstract Phenolic compounds occur in effluents from a wide variety of industrial operations, and they present toxicity and generate environmental problems. The treatment of these wastes via enzyme immobilization indicates that peroxidase (E.C.1.11.1.7) is the enzyme with the widest application. In the same process, biodegradable polymers have generated significant interest from research and industrial communities. Here we applied biopolymers from sugarcane bagasse (SB) and Cerrado cashew-tree polysaccharide (PEJU-GO) as supports for peroxidase immobilization from crude green zucchini extract via physical adsorption and covalent bonding. In addition, we used these systems in the removal of phenols from industrial effluents. Electron microscopy showed a fibrous surface for SB and a microporous material for PEJU-GO, characteristics that facilitate the immobilization. The infrared of both materials elucidated characteristic bands of sugars. For operational stability after 30 days of storage, the immobilized peroxidase retained 69 and 50% activity for SB and PEJU-GO, respectively. The systems were able to remove up to 79% of phenolics from industrial wastes. Therefore, the biopolymers from sugarcane bagasse and cashew-tree polysaccharide are promising sources for biotechnology, especially when used for peroxidase immobilization. This will support enzymatic activity in laboratory practice, with homogeneous behavior in different pH conditions, at low cost, biodegradable, non-toxic and extracted in a sustainable way.

Abstarct This study explored the relationship between water fluoridation quality and development indicators at municipal level. In addition, fluoride concentrations found were classified based on two criteria for interpreting the samples. A cross-sectional ecological exploratory study was carried out including all municipalities of the metropolitan region of Great Vitória, ES, Brazil. From May to October 2016, 648 samples of water were collected covering water treatment plants responsible for more than 80% of the population of each municipality. The fluoride concentration of each sample was determined using ion-specific electrode and the results were classified according to the federal act and the criterion proposed by the Collaborating Center of the Brazilian Ministry of Health for Oral Health Surveillance. The outcome was the rate of values included in the optimal concentration interval and the independent variables were municipal-level indicators related to demographics, economics, sanitation, health conditions and human development characteristics. The Spearman test and Kappa statistic were used in the analysis. The percentage of samples presenting optimal fluoride concentration ranged from 68.1 to 81.4%, considering the two criteria used. The Kappa statistic between the criteria was 0.671 (p-value = 0.001). Human development, average coverage of supervised toothbrushing, and total population showed a strong positive correlation with the quality of fluoridation while infant mortality and tooth-extraction/dental procedures ratio showed a strong negative correlation. The plausibility of observed correlations encourages further investigations of potential causes.

Abstract The impact of rainfall on surfaces lacking vegetal cover can dissociate soil particles, thereby initiating the erosion process. This is known as rainfall erosivity and is expressed by the R factor in the Universal Soil Loss Equation. Agricultural areas often show seasonally erosion susceptibility throughout the year due to oscillations of the soil exposure rate and the vegetation change. Considering that approximately 30 million ha of the Mato Grosso State in Brazil is used for agriculture, this study aimed to predict and map the spatial and temporal variability of its territory. We evaluated the monthly (EI 30) and annual (R) erosivity for 158 rain gauge stations and spatialized the values of EI 30 and R by the Kriging method. It was observed that R values ranked as very high in the north, and high and medium-high in the south of Mato Grosso state. The mean value is 8835 MJ mm ha-1 h-1 year-1, considered high. Ninety-one percent of the annual erosivity was concentrated in the period between October and April, corresponding to the rainy season. The highest R factor values were found in the macro-regions of the northwest, north, west and medium-north of Mato Grosso State.

Abstract The importance of the preservation of water resources has resulted in the application of technologies such as nanostructured materials, which are able to minimize the impact associated with water contamination. This work evaluated the application of polyamide-66 (PA) pellets functionalized with silver nanoparticles (AgNPs) at polymer mass percentages of 0.05, 0.10 and 0.50% to disinfect of drinking water. Studies were carried out in three stages. The first stage was the synthesis of the silver nanoparticles by using silver nitrate as a metal precursor and sodium borohydrate as a reduction agent. The colloidal dispersion was characterized by UV-Vis spectrophotometry and transmission electron microscopy (MET). Afterwards, the nanostructures were incorporated into a polyamide-66 polymeric matrix. In the second stage, the silver ions leached from the polymer matrix in the water after a three-hour period were quantified in order to evaluate the limit established by Conama Resolution 357/2005, which imposes a concentration limit of 0.010 mg L-1. The best results were obtained with the application of 0.05% AgNPs in the polymeric matrix, yielding an average concentration of silver ions lixiviated of 0.008 mg L-1. The last step comprised the quantification of the antibacterial activity of the polymer matrix containing 0.05% of AgNPs against the microorganism E. coli using the Standard Test Method for Determining the Antimicrobial Agents Under Dynamic Contact Conditions. The samples containing 0.05% of AgNPs exhibited an antibacterial reduction of 97.89% after 24 h of incubation under stirring at room temperature (25°C).

Abstract The uncertainties present in hydrological models have made them difficult and often impossible to apply. This work evaluated the sensitivity of input parameters in the SWAT model used for the modeling of average monthly flow-discharge in the Jucu River Basin, located in the southeast portion of the state of Espírito Santo, Brazil. Sensitivity analysis was performed using the SWAT-CUP program, which uses the SUFI-2 algorithm. Four sensitivity analysis tests differing by the length of hydrological series, number of iteration and fluviometric station locations resulted in different sensitivity levels of input parameters used in the model. In this way, the present study emphasizes the need for a greater detailing of methodological processes used in the sensitivity analysis, so that different hierarchies of parameters can be obtained through the same tool.

Abstract The present paper presents a preliminary proposal for a framework for the Una River, located in the state of Pernambuco, divided into prevailing-use classes. This proposal integrates the results of an analysis of water quality parameters and a mathematical modeling performed along a section of the river. Data from six State Environmental Agency (CPRH) monitoring stations were used, which collected data for temperature, pH, DO, BOD, phosphorus, thermotolerant coliforms, turbidity, and color between 2002 and 2014. The mathematical model used was QUAL-UFMG and the parameters evaluated were DO and BOD. The results showed that the DO and BOD parameters were within the limits established by CONAMA Resolution No. 357/2005 for Class 2, but other parameters such as phosphorus presented nonconformities. Based on this, the proposed framework for the Una River covered Classes 1 and 2. It is hoped that such a proposal will serve as a reference for the basin committee in order to discuss and deliberate on the multiple uses preponderant along the river, aiming to approve and implement the framework.

Abstract Concern for environmental quality has increased in society because industrial and technological development has released high levels of contaminants into the environment, such as hydrocarbons. A technique widely used for bioremediation is biostimulation, which may be enhanced by microencapsulation. This research formulated slow-release nitrogen and phosphorus compounds using different polymer (Alginate/Capsul®, carboxymethyl cellulose) matrices and compared them with the agricultural product Osmocote® and mineral medium Bushnell-Haas as hydrocarbonoclastics biostimulation agents in the environment for pollutant bioremediation. N (nitrogen) and P (phosphorus) were immobilized using lyophilization and ionic gelation techniques. Experiments were conducted using encapsulated material and evaluated for biomass production, glucose consumption as organic carbon source and N and P supply. The immobilized carboxymethyl cellulose compound showed the best results of glycosidic degradation (66.7%) and microbial biostimulation (350 mg L-1 protein) compared to systems containing free nutrients (11.3% and 150 mg L-1 degradation glycosidic and microbial biostimulation, respectively). Thus, this compound is a potential slow release product for bioremediation processes.