Repositório RCAAP

Abstract Due to the scarcity of water in the semi-arid region of Northeast Brazil, in both quantitative and qualitative terms, the use of saline water in agriculture should be considered as one alternative for irrigated agriculture. This study therefore aimed to evaluate the photosynthetic pigments, growth and production of West Indian Cherry as a function of irrigation using waters with different salinity levels and potassium (K) fertilization, after grafting. The study was carried out in drainage lysimeters under greenhouse conditions, in a eutrophic Regolithic Neosol with sandy loam texture, in the municipality of Campina Grande, PB. The experiment was set in a randomized block design, to test two levels of irrigation water electrical conductivity - ECw (0.8 and 3.8 dS m-1) and four K2O doses - KD (50, 75, 100 and 125% of recommendation), with three replicates. The dose relative to 100% corresponded to 79.2 mg K2O kg-1 of soil. Irrigation with high salinity water stimulated the biosynthesis of chlorophyll b and carotenoids, while the chlorophyll a content and the growth of the cherry were reduced markedly in the post-grafting phase. The harmful effects of salinity on the total number of fruit and fresh mass of West Indian Cherry fruit were minimized with potassium fertilization.

Abstract “Pozzolan” is a slag from the burning of coal in power plants which has the potential to assist as a low-cost adsorbent for wastewater treatment. The excess of Phosphorus (P) in the environment can promote chemical pollution and harm ecosystems, especially water. It is therefore necessary to implement inexpensive techniques and processes for the efficient treatment of water and wastewater. In this context, this study evaluated the use of the pozzolanic fly ash material for P removal from wastewater for the development of low-cost treatment technologies for environmental restoration and remediation of water resources. The treatment systems were developed in batch configuration. The removal tests from a synthetic sample with a known concentration of P reached a maximum of 30% removal in concentration, even varying the pH and performing different treatments of the pozzolanic material. This low removal efficiency of Phosphorus led to a comparative test between different lots of pozzolan in order to verify if the results obtained were characteristic of the material itself or of the lot obtained. Also the P adsorption isotherms were constructed with the two lots achieving adsorption capacities from 0.87 mg g-1 to 74 mg g-1. This difference indicates that the low P removal efficiency in the preliminary tests is due to the characteristics of the substrate of the first lot. Tests on a real effluent using the pozzolan from the second sample lot indicated a 99% efficiency of P removal, with an initial concentration of Phosphorus in the effluent of 5.5 mg L-1.

Abstract The consumption of contaminated water is a major source of heavy metal contamination in humans and animals. This study therefore aimed to assess Cd, Cu, Mn, Ni, Pb, and Zn levels in water used for human and animal consumption and vegetable crop irrigation in Camocim de São Félix, Pernambuco, Brazil. Water samples were collected on the studied farms from an artesian well and reservoirs used for human and animal consumption as well as for crop irrigation. The results showed that concentrations of Cd (> 0.001 mg L-1), Ni (> 0.025 mg L-1) and Pb (> 0.01 mg L-1) were above the maximum allowable limits established under Brazilian law, indicating the need for a preventive monitoring program and immediate intervention initiatives aimed at the sources of contamination. The results demonstrate the need to quantify heavy metal content in vegetable crops, since their contamination by irrigation water may make them harmful to human health. Rainfall has a seasonal effect on heavy metal concentrations in water, showing a significant effect on Pb levels, whereas Cd and Ni content was less dependent on seasonal variation.

Abstract The Escherichia coliT 90 parameter is widely employed in outfall plume hydrodynamic models. Although there is a great deal of academic literature estimating T 90 , no standard methodology has been validated so far. Estimation of die-off rates should consider many other biological, chemical and physical processes. Over the last three decades, while a great deal of new knowledge about microbial biology and ecology has become available, it has not been fully incorporated into the overall research. Consequently, hydrodynamic models of sewage plumes lack consistency with environmental dynamics and frequently do not fully reproduce processes. This article scrutinized the relevant works that could improve T 90 assessment using the most robust and realistic approaches. The most important related literature since the 1990s was considered, together with earlier relevant works. The research focused on techniques and methodologies, especially their ecologic and cellular biology aspects. A brief discussion of the methods applied to evaluate the T 90 of bacteria examined aspects like representativeness of incubation, incubation scale, measurement procedures and models’ representations of bacterial decay. The factors affecting population decay, such as solar radiation, salinity and interaction with solids, were considered in the light of the very large literature registry. Finally, biological aspects affecting decay, like predation and genetic resistance, were also analyzed. The resulting updated understanding of T 90 may contribute to better managerial procedures that could improve water quality in freshwater and coastal systems, and consequently improve human health outcomes.

Abstract Concentration time is an important parameter for drainage systems design and is closely related to the physiographic characteristics of a given hydrographic basin. Information from cartographic bases or images obtained by remote sensing, which present certain scales/resolutions, are often employed for the appropriation of concentration times. The present study sought to investigate the influence that the combination of different physiographic information, in different scales, and different calculation methods can produce in concentration times’ values. The applied methodology included a concentration times appropriation methods survey, identification of methods compatible with the study area characteristics, physiographic variables appropriation from information plans at different scales and concentration times determination for different regions. The results show that there is an equivalence between Tulsa District and US Corps of Engineers methods, and that these methods produce higher concentration times estimates than those produced by the George Ribeiro method. For the study area, the maximum calculated relative error was 52%.

Abstract The “heat island” phenomenon is one of many serious problems caused by rapid urban growth. This study therefore sought to characterize and quantify heat islands in Uberlandia, to evaluate the seasonality of these islands (winter-summer) and to identify the effect of surface coverage on their intensity. To identify intra-urban heat islands in Uberlandia, air temperature data were collected in two seasons (winter and summer) using mobile and fixed transects seasons. Transition measurements were recorded automatically every 0.5 seconds using a car-mounted thermos-hygrometer moving at an average of 40 km h-1. GPS was used to select approximately ten data points every 500 meters of each transect. Fixed weather stations measured air temperature at three sites in the region. Transect data analysis showed that the intra-urban heat islands were more intense in winter (ΔT = 2.2ºC) than in summer (ΔT = 1.2ºC) mainly because by reduction in atmospheric vapor in winter (dry season) and by higher rate of radiative cooling that is favored in permeable areas. The methodology used in the present study proved to be a quick and efficient way to carry out this type of monitoring.

Abstract This study sought to characterize the conditions of springs used for domestic consumption and to analyze their water quality. The springs are situated in catchment areas (drainage areas) with different soil uses in rural properties of the southern plateau of Santa Catarina, Brazil. To this end, 56 springs used to supply rural properties were selected in the counties of Lages, Otacílio Costa, São José do Cerrito, Painel, and Bocaina do Sul. The water catchment area of the springs were described in detail with regard to topography, management, forest, protection, fences, channels to contain runoff, and macroscopic aspects of water. In addition, the water was analyzed for total and fecal coliforms, pH, dissolved oxygen, electrical conductivity, temperature, clarity, and nitrate and total phenol contents. The samplings for water analysis were performed in compliance with Standard Methods for Examination of Water and Wastewater (APHA). The above parameters were evaluated under the following soil uses in the drainage areas: native forest, native grassland, planted pine forest, and cropland. Data were analyzed by comparison of means by the Student's t test (p <0.05). More than 80% of the springs were found to be contaminated with fecal coliforms. The main risk factors for microbiological contamination in the region are extensive cattle ranching and the lack of adequate protection of the springs in most properties, with emphasis on the catchment areas of native grassland and native forest. Springs in pine forest areas have the lowest mean pH and the highest phenol content.

Abstract Human demand for the provisioning services of the ecosystem has been rising and shows the existence of trade-offs in their generation. Brazil is a great producer of agricultural commodities and animal protein, which generates a large amount of residual biomass throughout the production process, especially animal highly polluting waste concentrated in small areas. Ecosystems provide a wide range of services that are of fundamental importance to the well-being, health, subsistence and survival of human beings. The impacts of the waste generated by confined animals can degrade the ecosystem and reduce the services it can supply. Using waste to generate biogas does not require direct resources from the ecosystems to generate energy. In this context, it is an energy product classified as a provisioning service and, at the same time, an ecosystem regulating service, as it mitigates undesirable effects in the environment. The main goal of the classification of biogas as an ecosystem service is to explore its contributions to the ecosystem and to human well-being.

Abstract The fly ash of coal, generated in a thermoelectric plant, was used to synthesize zeolite by hydrothermal treatment with a sodium hydroxide solution. The zeolite synthesized was used as an adsorbent of metals (Fe and Mn) and of the methylene blue dye in water. The characterization of the zeolite showed that silicon oxide is the main compound in its composition, followed by aluminum, iron, sodium and calcium, which together correspond to more than 86% of its composition. These were used to investigate the kinetic parameters of adsorption and the isotherm of the metals and the methylene blue dye in aqueous solutions. Three kinetic models, pseudo-first order, pseudo-second order and intraparticle diffusion were used to predict adsorption rate constants. The adsorption kinetics of the dye and metals followed the pseudo-second order kinetics and reached equilibrium in 15 minutes with a 99% removal rate for metals, independently of the pH. The values ​​of the diffusion constants (K2) for iron in pH 5, 7 and 8 were 1.3158; 1.3881 e 0.6053 mg.g-1.min-1 and for manganese 1.2511; 1.5239 and 1.4336 mg.g-1.min-1, respectively. For methylene blue, the removal rate was 90% and the constant (K2) value was 0.5437 mg.g-1.min-1. The studies showed the existence of different stages in the adsorption of the metals and the methylene blue dye in zeolite.

Abstract Fungi have a large capacity to produce enzymes that are capable of degrading compounds. In this regard, soluble dyes are often used as a means of evaluating and selecting strains with potential for biodegradation. This study verified the capacity of the strains of Pleurotus sp. in degrading methylene blue dye, in order to identify the strains with potential for the bioremediation. For this reason, a total of seven strains of Pleurotus sp. were grown in a potato liquid medium with the methylene blue dye at the concentrations of 0.02 g L-1 and 0.04 g L-1. The results of the absorbances showed that all the isolates were visibly able to reduce the media staining following seven days of growth. However, a reduction of approximately 80% in the staining was observed for the strains named ERY, HI, and SB compared to the control. Thus, it was observed that these strains could be used in the color removal bioprocesses and in the biodegradation of pollutant compounds.

Abstract Natural water distillation can destroy and/or inactivate microorganisms that are sensitive to heat and ultraviolet radiation (UV). This method is currently used to provide fresh water in ships and in the desalination of brackish water. For the development of this research, a pilot-scale solar still was built and installed in the southern region of Brazil, in order to assess its efficiency in water disinfection, which was based on the most probable number (MPN) of total coliforms and Escherichia coli, in addition to the DNA copy number of human adenovirus type 5 (HAdV-5) in raw, undistilled samples and in treated distilled water. Results showed that the distillation process removed 100% of total coliform and Escherichia coli and 4.5 log (99.997%) of HAdV-5, which meets the microbiological standards for drinking water according to national Brazilian regulations, as well as USEPA and HEALTH CANADA requirements.

Abstract Changes in land use alter regional microclimate. This study compared the microclimate in understories of a mango orchard and a degraded area in the municipality of Salinópolis, in the northeast of the Brazilian State Pará, eastern Amazon. In both environments, the microclimate was monitored through collecting data on the following variables: maximum, minimum and average air temperature, air thermal amplitude and vapor pressure deficit. The microclimate was monitored daily during four seasons: early rainy season, late rainy season, early dry season and late dry season, between December 2015 and November 2016. Vegetation coverage was the most important factor to soften maximum and average air temperature in the understories. Lower values of meteorological variables were observed in the mango orchard understory, especially during late rainy season and late dry season, except for minimum air temperature, which was lower in the understory of the degraded area, especially during the late rainy season. The microclimate in the understory differed between both environments, and mango orchards may ameliorate the understory microclimate more efficiently than degraded areas; therefore, the mango orchard can be used as an alternative for the rehabilitation of degraded areas.

Abstract Although organic agriculture in Brazil targets mainly local consumers, there is growing demand for research related to commercializing this sector abroad. A study was done in Europe on the perception of entities related to this theme, specifically on Participatory Guarantee Systems (PGS), the feasibility of equivalence between the countries, and control procedures. An exploratory study was conducted through interviews with five organic certification bodies, two in Switzerland, three in Italy, and with a producer association in Italy. PGS is little known in Europe in general and it is suggested that it be better disseminated in the member countries. PGS has been evaluated positively for reducing certification costs and promoting benefits from a social aspect, but it can fail in organic compliance and in large scale production. There are significant differences that must be overcome in order to establish equivalence, such as the lack of homogeneity among European countries on control procedures, the existence of PGS in Brazilian legislation, lack of wild crop products in Europe, different conversion periods, and the requirement of a higher number of inspections in Brazil. Equivalence is seen as beneficial to both Europe and Brazil, and it would therefore be appropriate to promote its viability. The Brazilian law on organic agriculture is taken as very restrictive and complex.

Abstract Life Cycle Assessment (LCA) was applied to estimate and analyze the environmental impacts from the construction and operation phases of a full-scale wastewater treatment plant (WWTP) located in the municipality of Lauro de Freitas, Bahia, Brazil. The WWTP process consists of the association of an Upflow Anaerobic Sludge Blanket (UASB) reactor followed by four constructed wetlands (CWL) and a disinfection step. The functional unit was defined as one cubic meter of treated effluent during the useful life of this WWTP (20 years). The LCA was carried out using SimaPro® software and the Centre of Environmental Science (CML) assessment method. The environmental impacts during construction phase were mainly from the wooden forms for concrete and the use of reinforcing steel. During the operation phase, the chlorine used as effluent disinfectant caused the greatest impacts in the abiotic depletion and acidification categories. Macronutrient concentrations present in the treated effluent and the methane generated also caused significant environmental impacts during the WWTP’s useful life. The results obtained highlight the importance of the application of a methodology like LCA to assist in decision-making with regard to the implementation, construction and operation of a WWTP.

Resumo O monitoramento para a previsão de cheias de pequenas bacias hidrográficas é de grande importância tendo em vista a relação dos recursos hídricos com a sociedade, pois pode garantir o uso sustentável às comunidades urbanas de cidades lindeiras à bacia. O rio Aquidauana está inserido na planície Pantaneira sendo considerado vulnerável à inundações, no entanto, falta de um sistema eficiente para previsões de cheias e inundações. Assim, este estudo propõe um sistema de previsão probalística de enchentes para a bacia do Rio Aquidauana. Para tanto foram utilizadas as redes neurais artificiais (RNAs) do tipo MultiLayer Perceptron (treinamento back-propagation) com parâmetros otimizados pelos Algoritmos Genéticos. A RNA foi treinada e avaliada com base em dados de chuva acumulada (mm) e nível de rio (cm) à montante entre os anos de 1995 a 2014. A previsão realizada foi de 1 a 5 dias, tendo como melhor desempenho o modelo para 1 dia de previsão, com resultado de coeficiente de determinação e erro quadrático médio de 0,93 e 30 (cm), respectivamente.

Abstract Cowpea is a crop with great economic, social and food importance in semi-arid regions, but its production is drastically reduced by the water deficit in these regions, requiring better management strategies that allow the crop’s production. This study therefore aimed to evaluate the photosynthetic efficiency and production of cowpea cultivars under deficit irrigation replacement levels. The experiment tested three cowpea genotypes (G1 = ‘BRS Aracé’, G2 = ‘BR 17 Gurguéia’ and G3 = ‘BRS Marataoã’) and four irrigation depths (40, 60, 80 and 100% of ETc), resulting in a 3 x 4 factorial scheme, arranged in randomized complete blocks design with four replicates. During the experiment, the gas exchanges, chlorophyll a fluorescence and production of the cowpea genotypes under deficit irrigation were evaluated. Carbon fixation in the photosynthetic metabolism of cowpea plants was reduced by accentuated water deficit, regardless of the genotype. The low stress severity was indicated by the lack of effects on chlorophyll fluorescence, indicating that the reduction in the rate of carbon assimilation was due to the stomatal effects. The irrigation with 80% of ETc can be used in the cultivation of the respective cultivars, but with small losses in the production. Among the genotypes, ‘BRS Marataoã’ stands out with respect to yield, with higher values for weight of pods and green beans.

Abstract Particulate matter is the mixture of solid and liquid particles. It may at times cause adverse effects to human health, in the climate, ecosystem and materials. The objective of this study was to identify the sources emitting particulate matter that contributes to environmental pollution at two sites in Belo Horizonte city. The metropolitan region of Belo Horizonte is characterized by numerous mining activities and other industries, high population and, consequently, a high number of vehicles. There are therefore several sources emitting pollutants into the atmosphere. Airborne particulate matter was collected in air filters during approximately one year using a high-volume sampler in strategic points. The concentration of particulate matter results showed that, in general, the values were 40% higher than the values recommended by legislation. During the summer rainy season, no sample exceeded the recommended limits at both sampling sites. The elemental composition was determined through neutron activation analysis and these values were considered variables in the multivariate statistical analysis for the identification of the main sources of particle emission and their contributions. The results confirmed a significant influence of the soil and motor vehicles in the degradation of the region’s air quality.

Abstract To maintain quality measurement of water consumption, it is necessary to know the metrology of single-jet water meters over time. Knowing the accuracy of these instruments over time allows establishing a metrological operation period for different flow rates. This will aid water companies to optimize management and reduce economic losses due to unaccounted water consumption. This study analyzed the influence of time on the measurement error of single-jet water meters to evaluate the deterioration of the equipment and, with that, launch the metrological operation period. According to standards 8316 and 4064 of the International Organization for Standardization (ISO), 808 meters of metrological Class B were evaluated in six water supplies, with age ranges of 3.7 to 16.4 years of use. The measurement error was estimated by comparing the volume measured in a calibrated tank with the volume registered by the meters at flow rates of 30, 120, 750 and 1,500 L h-1. The metrological operation period of the meters was obtained for each flow rate by the relation between error of measurement and time of use (simple linear regression). According to the results, the majority of the equipment presents increasing under-registration errors over time, more pronounced at low flow rates and with less favorable operating conditions. The metrological operation period for flow rates of 30, 120, 750 and 1,500 L h-1 is estimated at approximately 3, 8, 14 and 13 years. This operation period combined with consumption patterns of users will establish the best time to replace the meters.

Abstract This work evaluated the removal of total Kjeldahl nitrogen (TKN) and total phosphorus (P) through electrocoagulation and used aluminum electrodes to optimize the potential differential (pd) and hydraulic retention time (HRT) variables in a batch reactor. The experimental design used was Rotatable Central Composite Design (RCCD). The application of the electrocoagulation in the treatment of effluents from pig slaughterhouses and packing plants proved to be efficient in relation to the removal of TKN and total phosphorus, obtaining maximum efficiency equal to 67.15% and 99%, respectively. The maximum TKN removal value was found in Test 12, where treatment conditions were 30 minutes for HRT and 20 volts for pd, which corresponds to 0.86 A of electric current and a current density of 17.2 mA cm-2. For P, the only test that removed below 99% was the first. Through statistical analyses, it was only possible to obtain a mathematical model for TKN removal. While the response surface graph did not present a defined range of the best conditions for the independent variables, it was possible to observe the tendency for better removal, a wide range of pd and values over 30 minutes for retention time.

Abstract The quality of drinking water flowing in a distribution network can possess corrosive characteristics that may cause the material degradation of pipes and accessories. This problem can result in reduction of the service life of pipes and create a major public health problem. The agreement between the physical-chemical water quality analysis and national standards are not enough to confirm the balance of the water quality in terms of corrosion. In order to predict pipe corrosion in water distribution system networks, the corrosive trend was evaluated using the Langelier (LSI), Ryznar (RSI), and Larson-Skold (LRI) indexes based on measurements of pH, temperature, total dissolved solids, alkalinity, calcium hardness, sulfate and chloride. This study was setup with 180 samples collected in six zones of the distribution network, from July to December of 2017, according to the standard methods for the analysis of drinking water. The results indicate a variation of the LSI from -1.22 to -1.68; RSI from 9.75 to 10.52 and LRI from 0.46 to 0.77. A linear model was fitted for each index to predict the corrosion with the water quality conditions of this study case. Therefore, the drinking water of the city of Azogues, Ecuador has a corrosive tendency from significant to severe. Corrosion indices were calculated to provide useful information on the water's corrosiveness. These results indicate the need to constantly monitor the corrosion rate in the distribution network and conduct a laboratory study to adjust effective parameters such as pH, in order to control corrosion.