Revista Ambiente & Água - An Interdisciplinary Journal of Applied Science

1-14

Authors: Diego Antonio França de Freitas; Julio Issao Kuwajima; Gesmar Rosa dos Santos

The novel coronavirus pandemic has resulted in global socioeconomic impacts; however, there is still a need to improve understanding and data about its form and patterns of propagation. Therefore, studies on the role of water resources and sanitation should be prioritized, given the potential to serve as a means of dispersing the SARS-CoV-2 virus, which causes COVID-19 disease. So far, the RNA of the transmitting virus has been detected in domestic sewage in several countries, but there is, so far, no evidence of contamination by direct contact with these effluents. Even so, poor regions without adequate treatment of water and sewage, as occur in Brazil, must act in order to develop efficient policies to improve water quality aimed at public health. One of the options is the formation of a Hub that aggregates the various interrelated aspects of water and sanitation into a cohesive and actionable whole. It is essential to combine investment, research, and monitoring of water and effluent quality to improve sanitary security, water quality and human health, with an emphasis on the poorest sectors. The Hub would also serve as a means of controlling and monitoring the dispersion of pathogens such as the SARS-CoV-2 virus, thus mitigating economic and societal impacts.

1-18

Authors: Admilson da Penha Pacheco ; Renato Filipe Faria Henriques; Paulo Marcelo Vieira Ribeiro

The safety of a dam is the result of a series of factors, including structural, geotechnical, hydraulic, operational and environmental aspects. In Brazil, Law No. 12.334 of September 2010 establishes the National Dam Safety Policy, which requires safety reports and monitoring inspections for existing dams. The inspection comprises a set of devices installed on the dam, which are used to assess the structural behavior based on performance parameters of the structure, such as displacements, flows, stresses, slopes and others. Dam auscultation procedures, historically, have been performed since the 1950s. Since then, there have been significant advances in instrumentation and dam auscultation methods. This work presents a theoretical approach on technical and scientific aspects of dams in Brazil, based on a state-of-the-art literature review, involving auscultation of dams in the context of design codes, concepts, instrumentation, safety, procedures and monitoring methods.

1-13

Authors: Otacílio Correia Lima Neto; Alfredo Ribeiro Neto; Fellipe Henrique Borba Alves; José Almir Cirilo

Flash floods are observed in the Una River Basin, Pernambuco/Brazil. This particular type of flood is a short-duration hydrological event with occurrence of the peak flow within minutes to few hours after the onset of the rainfall, taking place typically in mountainous regions. The objective of the paper was to assess the sub-daily hydrological and hydrodynamic modeling of flood events in 2011 and 2017. Sub-daily precipitation and streamflow were applied to the models Hydrologic Engineering Center-Hydrologic Modeling System (HEC-HMS) and River Analysis System (HEC-RAS). Model evaluation methods such as Nash-Sutcliffe efficiency (NSE), percent bias, and the ratio of the root mean squared error to the standard deviation of measured data (RSR) were used in the calibration process. The maximum infiltration rate and the Snyder peak coefficient estimation were the most sensitive parameters in the hydrological model. The calibration of the HEC-HMS showed good performances (Catende station NSE=0.78 and RSR=0.46; Palmares station NSE=0.68 and RSR=0.57). During HEC-RAS 1D flow simulations, steep regions in the Una River caused numerical instabilities. The 2D solution was needed to overcome this problem, allowing us to represent the water level in the city of Palmares satisfactorily.

1-19

Authors: Anna Virginia Muniz Machado; Marina Thurler Nogueira; Lucas Magalhães Carneiro Alves; Norbertho da Silveira Quindeler; Juliana da Costa Dias Silva; Pedro Antonio de Paiva Aranha; Ricardo Pereira Gonçalves; Natália Lascas Soares de Siqueira

Rural communities usually are poorly covered by basic services, including water supply services (WSSs). Within this context, community management of water is a promising alternative to address this issue, with many successes all over the world. This approach also contributes to the achievement of Sustainable Development Goal (SDG) 6, which intends to universalize water access. This paper evaluates the WSSs provided by eleven rural community organizations from Espírito Santo, Brazil. All of those participate in the sanitation program “Pró-Rural” created by Cesan (Companhia Espiritosantense de Saneamento), the state water concessionaire, to reach small-sized rural settlements. For this purpose, Siasar was used, an informational tool that enables the identification of elements in the rural water supply systems (RWSSs) that can enhance or hinder their performance. The results verified that the communities were able to maintain a satisfactory level of quality of the WSSs, although there were perceptible fragilities regarding the distance between internal (communities and service providers) and external (technical assistance providers) actors that can decrease the quality of the WSS or even lead to its interruption if not addressed.

1-12

Authors: Fabiana Alves Fiore; Suzelei Rodgher; Cristiane Yumi Koga Ito; Vivian Silveira dos Santos Bardini; Luis Miguel Gutiérrez Klinsky

Among the waste produced daily by communities are those resulting from the treatment of water for public supply, with local specificities that reflect the characteristics and uses of the land. Despite the continuous generation and inadequate disposal still current in Brazil, there is little information on these residues. The data related to the composition of these sludges are essential for the study of alternatives for beneficial uses and for determining the risks to the environment and human health from inadequate disposal. It is in this context that the present study was developed, with the objective of identifying the physical-chemical characteristics of sludge produced in water treatment plants (WTPs) and of verifying the presence of these elements in the waters of the source used for supply. Such research was carried out through a case study in two WTPs in the state of São Paulo that perform surface abstraction. Therefore, in each of the WTPs, samples of densified sludge, representative of the dry and rainy periods, were characterized. The chemical findings of the sludge have been compared to the historical series of a decade of monitoring of the water quality of the sources of these WTPs. Among the main results, concentrations above the reference limits for the inert residues of aluminum, iron, manganese and barium in sludge are highlighted, as well as the existence of iron and manganese in the raw water collected and the variations in the concentrations of iron, sodium and manganese in the sludge due to the climatic conditions.

1-11

Authors: Marta Sória; Vitor Emanuel Quevedo Tavares; Marília Alves Brito Pinto; Lizete Stumpf; Daiane Zarnott; Jéssica Bubolz; Bernardo Gomes Nörenberg

Water-quality monitoring is one of the main instruments for water-resource management. This work therefore evaluated the water quality of the contribution basin of the Sinnott water treatment plant as well as the relationship between physicochemical water parameters, and analyzed the seasonal variation of water quality parameters as a function of rainfall. The study area encompassed the contribution basin of the Sinnott water treatment plant, formed mainly by the drainage areas of the Pelotas stream and its tributary, the Quilombo Stream, located in the city of Pelotas - Rio Grande do Sul, Brazil. A set of 118,368 data points for each stream was analyzed between 2007 and 2012. The following water quality parameters were evaluated: turbidity, temperature, color, pH, hardness, dissolved oxygen, organic matter, and alkalinity. Results showed that dissolved oxygen and water pH values conformed with Brazilian legislation in the 6 years evaluated. However, water color was the parameter that remained the greatest number of days above the set limits, mainly in the Pelotas Stream. Result indicates the need for conservation actions in the catchment, especially considering the importance of color for the assessment of water quality for public supply, in terms of both treatment costs and of public health. Highest values for water color, turbidity, and organic matter coincided with the occurrence of the highest rainfall values. Agricultural activities may potentiate sedimentation in the contribution basin of the Sinnott water treatment plant.

1-17

Authors: Rener Luciano de Souza Ferraz ; José Dantas Neto; Patrícia da Silva Costa ; Antônio Suassuna de Lima; Patrícia Ferreira da Silva; Rigoberto Moreira de Matos; Alberto Soares de Melo

Population growth and the need to exploit natural resources to produce food and guarantee food sovereignty reduce water availability, which can influence nutrient absorption capacity and production of plants. This study evaluated whether variations in soil water replacement levels promote changes in the mineral composition and biomass productivity of forage cactus varieties. A field experiment was conducted in a randomized block design with five levels of reference evapotranspiration replacement (25, 50, 75, 100 and 125% ETo) and three replicates. Contents of the macronutrients N, P, K, Ca, Mg and S; micronutrients Cu, Fe, Mn, Zn, Cl, Na and B; and biomass productivity were quantified in two varieties of forage cactus (‘Orelha de Elefante Mexicana’ and ‘Miúda’). The data were subjected to principal component and multivariate variance analysis. The mineral composition of the forage cactus varieties ‘Miúda’ and ‘Orelha de Elefante Mexicana’ can be optimized from soil water management, so as to obtain adequate nutritional balance for higher yield. The replacement level of 75% ETo promoted greater balance between nutrients in the cladodes of the forage cactus variety ‘Miúda’, while ‘Orelha de Elefante Mexicana’ had better nutritional balance with the replacement levels of 100 and 125% ETo. Soil water replacement levels of 100 and 125% ETo promote high accumulation of Na+ and Cl- ions in the cladodes of the forage cactus varieties studied. Highest biomass productivity of the varieties ‘Orelha de Elefante Mexicana’ and ‘Miúda’ was obtained with 75 and 100% ETo replacement levels, respectively. Among the varieties, ‘Orelha de Elefante Mexicana’ had a higher capacity for nutrient accumulation and biomass productivity, followed by ‘Miúda’, under the edaphoclimatic conditions of the Brazilian semiarid region.

1-20

Authors: Daniel Constantino Zacharias; Adalgiza Fornaro

The basins of Campos and Santos, the most important offshore oil reserves in Brazil, hold potential for being the largest offshore oil exploration fields in the next decades, mainly due to the oil located in the pre-salt layer. This region presents real conditions for the occurrence of intense atmospheric events added to the high velocity of the meanders of the Brazilian current. However, the increasing risk of accidents and damage in the region has been the subject of concern and discussion. The risks in the basins of Campos (2011) and Santos (2012) may not exhibit the the same potential for disastrous events as do those in the oil fields of Alaska and of the Gulf of Mexico, but accidents in these areas are not unlikely, as already evidenced by previous accidents under similar operating conditions (e.g. Chevron Platform accident in Campos Basin, RJ, Brazil, 2011). This paper highlights discussion of the multidisciplinary and substantial environmental features in oil exploration fields along the Brazilian coast based on Semi-Systematic Review methodology. The aspects evaluated cover not only geological traits, oceanic and meteorological circulation, but also current oil production, the most significant oil spill accidents recorded up to 2019 and the discussion about some current levels of seawater contamination.

1-13

Authors: André Luís Teixeira Fernandes ; Eusímio Felisbino Fraga Júnior; Márcio José de Santana; Reginaldo de Oliveira Silva; Marcelo Moreira Dias

Coffee irrigation has increased in the main Brazilian coffee regions. However, in recent years, with climate change, years with water deficits greater than 150 mm have been observed, affecting the vegetative and productive development of the crop and also the replenishment of surface and underground springs. One practice that increases soil water retention capacity is organic fertilization. This work evaluated different combinations of irrigation and organic fertilization on the yield and quality of coffee produced in the Minas Gerais cerrado region. The treatments were: T1: total irrigation; T2: no irrigation; T3: total irrigation + organic fertilization (chicken manure, 10 ton ha-1); T4: no irrigation + organic fertilization (chicken manure, 10 ton ha-1); T5: 50% irrigation + organic fertilization (chicken manure, 10 ton ha-1). After 7 harvests, it was concluded that the treatment that combined organic fertilization with application of half of the necessary irrigation presented the best yield, superior to the treatment with total irrigation and exclusively mineral nutrition.