cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.12171234
title: Prediction of monthly flows for Três Marias reservoir (São Francisco river basin) using the CFS climate forecast model

description: ABSTRACT Despite the water crisis in 2016, 76% of the energy in Brazil was generated by hydroelectric plants, which shows that the Brazilian system is still strongly dependent on the hydrological conditions of basins. Therefore, the flow forecasts for these plants subsidize the decision making within the scope of the Electric Sector, since they allow the evaluation of the operational conditions of the hydroelectric and thermoelectric plants through the use of energy optimization models, providing gains in the operations of SIN (Sistema Interligado Nacional – the Brazilian National Interconnected System). The precipitation forecast is of fundamental importance for the elaboration of these hydroelectric flow forecasts. For energy evaluations, the DECOMP and NEWAVE models are used, with the GEVAZP model being applied to generate scenarios through an AR (p) (autoregressive) model. Accordingly, this study shows the impact of precipitation forecast on flow predictions in the climate horizon. For this, a statistical correction was made in the rain predicted by the CFS (Climate Forecast System) model, which tends to overestimate the predicted rain, with rainfall-flow models being calibrated. Tests were performed with this new modeling system and the results, in the form of scenarios, were compared with the scenarios generated by the GEVAZP model, showing the possibility of reducing the generated range by the latter, consequently causing the DECOMP model to not consider ranges with little or no probability of occurrence, which can improve the optimization of the SIN operation planning. This work also shows that the SMAP model exhibited better performance when compared to the Neural Networks model, in terms of the average flow range predicted in relation to the observed flow. There was a clear improvement in the flow predictions with the incorporation of the rain observed one month ahead in the simulations, mainly in the forecast of high flows. Finally, the climate indices had a good relationship with the flow and rain variables.
DOI: 10.6084/m9.figshare.12171234.v1
title: Prediction of monthly flows for Três Marias reservoir (São Francisco river basin) using the CFS climate forecast model

description: ABSTRACT Despite the water crisis in 2016, 76% of the energy in Brazil was generated by hydroelectric plants, which shows that the Brazilian system is still strongly dependent on the hydrological conditions of basins. Therefore, the flow forecasts for these plants subsidize the decision making within the scope of the Electric Sector, since they allow the evaluation of the operational conditions of the hydroelectric and thermoelectric plants through the use of energy optimization models, providing gains in the operations of SIN (Sistema Interligado Nacional – the Brazilian National Interconnected System). The precipitation forecast is of fundamental importance for the elaboration of these hydroelectric flow forecasts. For energy evaluations, the DECOMP and NEWAVE models are used, with the GEVAZP model being applied to generate scenarios through an AR (p) (autoregressive) model. Accordingly, this study shows the impact of precipitation forecast on flow predictions in the climate horizon. For this, a statistical correction was made in the rain predicted by the CFS (Climate Forecast System) model, which tends to overestimate the predicted rain, with rainfall-flow models being calibrated. Tests were performed with this new modeling system and the results, in the form of scenarios, were compared with the scenarios generated by the GEVAZP model, showing the possibility of reducing the generated range by the latter, consequently causing the DECOMP model to not consider ranges with little or no probability of occurrence, which can improve the optimization of the SIN operation planning. This work also shows that the SMAP model exhibited better performance when compared to the Neural Networks model, in terms of the average flow range predicted in relation to the observed flow. There was a clear improvement in the flow predictions with the incorporation of the rain observed one month ahead in the simulations, mainly in the forecast of high flows. Finally, the climate indices had a good relationship with the flow and rain variables.
DOI: 10.6084/m9.figshare.12210374.v1
title: Fate and transport of compounds with estrogenic activity in reconstructed soil columns

description: ABSTRACT Endocrine disruptors (ED) are exogenous agents capable of deregulating the normal functioning of the endocrine system in humans and animals. The ED entry routes in the environment highlight the launch of domestic and agricultural wastewater in water bodies. This work aims to evaluate the occurrence, mobility and biosorption attenuation of hormones and antibiotics in soil columns in the application of agricultural and domestic waste and rain simulation. Soil columns, which were filled with soil from an agricultural area, were installed under the conditions of a swine wastewater application (ARS) at a dose of 50 m3/ha with and without the biosorbent effect and human urine at a rate equivalent to nitrogen compared with ARS. The estrogen concentrations were observed by High-performance liquid chromatography coupled with diode array detector (HPLC-DAD), and the mass balance was developed to evaluate the estrogen removal in the soil profile. The occurrence of hormones in all analyses was approximately 20%. Pine bark adsorbent was found to be considerably efficient in removing hormones from liquid matrices. The mass balance of the soil columns with adsorbent exhibited an estrogen recovery in the matrix applied to less than a 1% rate. For comparison, the soil columns without adsorbent obtained a mass transit about 20% of the total applied.
DOI: 10.6084/m9.figshare.12210374
title: Fate and transport of compounds with estrogenic activity in reconstructed soil columns

description: ABSTRACT Endocrine disruptors (ED) are exogenous agents capable of deregulating the normal functioning of the endocrine system in humans and animals. The ED entry routes in the environment highlight the launch of domestic and agricultural wastewater in water bodies. This work aims to evaluate the occurrence, mobility and biosorption attenuation of hormones and antibiotics in soil columns in the application of agricultural and domestic waste and rain simulation. Soil columns, which were filled with soil from an agricultural area, were installed under the conditions of a swine wastewater application (ARS) at a dose of 50 m3/ha with and without the biosorbent effect and human urine at a rate equivalent to nitrogen compared with ARS. The estrogen concentrations were observed by High-performance liquid chromatography coupled with diode array detector (HPLC-DAD), and the mass balance was developed to evaluate the estrogen removal in the soil profile. The occurrence of hormones in all analyses was approximately 20%. Pine bark adsorbent was found to be considerably efficient in removing hormones from liquid matrices. The mass balance of the soil columns with adsorbent exhibited an estrogen recovery in the matrix applied to less than a 1% rate. For comparison, the soil columns without adsorbent obtained a mass transit about 20% of the total applied.
DOI: 10.6084/m9.figshare.12171228
title: Internal loading potential of phosphorus in reservoirs along a semiarid watershed

description: ABSTRACT Sediments are important to nutrient dynamics, especially due to phosphorus internal loading. Several studies have observed that internal loading could prevent water quality from improving in lakes, even when external phosphorus loading is significantly decreased. Therefore, there is an urgent need to assess the potential release of phosphorus contained in the sediment, and thus, its potential to impact water quality. In this study, the vertical and horizontal distributions of distinct phosphorus forms in the bottom sediments of artificial reservoirs, located at Forquilha watershed (Ceará, Brazil), were investigated through sequential chemical fractionation. The reservoirs Lagoa Cercada (R#1), Riacho do Algodão (R#2), Riacho Verde (R#3), Cachoeira (R#4), Chagas Manu (R#5), Quandu (R#6) and Balanças (R#7) were investigated. Reservoirs R#1 (most downstream reservoir of the watershed) and R#7 (most upstream reservoir of the watershed) had higher concentrations of total phosphorus (PT) and lower pH values, potentially exerting greater influence in phosphorus concentration in the water column. Reservoirs R#3 and R#4 presented a predominance of residual phosphorus (PRe), the least available fractions of phosphorus and thus, presented a lower potential for internal loading. Reservoirs R#5, R#1 and R#2 showed a tendency of decreasing total phosphorus (PT) as the sediment depth increased, probably indicating an increase of allochthonous phosphorus loading along time. Reservoir R#6 showed the predominance of PFeAl and PCa fractions on points A and B, respectively, showing that the characteristics of the sediments may vary in the same reservoir. Mobile (PM) and iron and aluminum-bound phosphorus (PFeAl) were the least and the most abundant fractions in most of the samples analyzed, respectively.
DOI: 10.6084/m9.figshare.12171228.v1
title: Internal loading potential of phosphorus in reservoirs along a semiarid watershed

description: ABSTRACT Sediments are important to nutrient dynamics, especially due to phosphorus internal loading. Several studies have observed that internal loading could prevent water quality from improving in lakes, even when external phosphorus loading is significantly decreased. Therefore, there is an urgent need to assess the potential release of phosphorus contained in the sediment, and thus, its potential to impact water quality. In this study, the vertical and horizontal distributions of distinct phosphorus forms in the bottom sediments of artificial reservoirs, located at Forquilha watershed (Ceará, Brazil), were investigated through sequential chemical fractionation. The reservoirs Lagoa Cercada (R#1), Riacho do Algodão (R#2), Riacho Verde (R#3), Cachoeira (R#4), Chagas Manu (R#5), Quandu (R#6) and Balanças (R#7) were investigated. Reservoirs R#1 (most downstream reservoir of the watershed) and R#7 (most upstream reservoir of the watershed) had higher concentrations of total phosphorus (PT) and lower pH values, potentially exerting greater influence in phosphorus concentration in the water column. Reservoirs R#3 and R#4 presented a predominance of residual phosphorus (PRe), the least available fractions of phosphorus and thus, presented a lower potential for internal loading. Reservoirs R#5, R#1 and R#2 showed a tendency of decreasing total phosphorus (PT) as the sediment depth increased, probably indicating an increase of allochthonous phosphorus loading along time. Reservoir R#6 showed the predominance of PFeAl and PCa fractions on points A and B, respectively, showing that the characteristics of the sediments may vary in the same reservoir. Mobile (PM) and iron and aluminum-bound phosphorus (PFeAl) were the least and the most abundant fractions in most of the samples analyzed, respectively.
DOI: 10.6084/m9.figshare.12210623
title: Influence of El Niño and La Niña phenomena on seasonality of the relative frequency of rainfall in southern Amazonas mesoregion

description: ABSTRACT The global and Amazon climate change, mainly in rainfall, due to the El Niño and La Ninã phenomena. The objective of this study was to analyze the relative frequency (RF) of rainfall, in different periods of the day, during occurrences of El Niño, La Niña events and neutrality condition. The research was carried out in the Southern mesoregion of the state of Amazonas (Apuí, Boca do Acre, Lábrea, Manicoré and Humaitá). Data were analyzed by the Spiegel´s method. The rainfall data were obtained from the Global Land Data Assimilation database from January 1st, 2000 to December 31st, 2018. Data were made available every three hours and integrated into six hours. RF of rainfall was higher in the afternoon in La Niña, Neutro and El Niño years in all municipalities. The RF in La Niña year was higher than during El Niño. The RF during the Neutral year was higher than during El Niño in Apuí and Boca do Acre, and had no difference in Lábrea, Manicoré and Humaitá. The rainfall in the southern Amazon mesoregion was more frequent during the afternoon.
DOI: 10.6084/m9.figshare.12210623.v1
title: Influence of El Niño and La Niña phenomena on seasonality of the relative frequency of rainfall in southern Amazonas mesoregion

description: ABSTRACT The global and Amazon climate change, mainly in rainfall, due to the El Niño and La Ninã phenomena. The objective of this study was to analyze the relative frequency (RF) of rainfall, in different periods of the day, during occurrences of El Niño, La Niña events and neutrality condition. The research was carried out in the Southern mesoregion of the state of Amazonas (Apuí, Boca do Acre, Lábrea, Manicoré and Humaitá). Data were analyzed by the Spiegel´s method. The rainfall data were obtained from the Global Land Data Assimilation database from January 1st, 2000 to December 31st, 2018. Data were made available every three hours and integrated into six hours. RF of rainfall was higher in the afternoon in La Niña, Neutro and El Niño years in all municipalities. The RF in La Niña year was higher than during El Niño. The RF during the Neutral year was higher than during El Niño in Apuí and Boca do Acre, and had no difference in Lábrea, Manicoré and Humaitá. The rainfall in the southern Amazon mesoregion was more frequent during the afternoon.
DOI: 10.6084/m9.figshare.12210545
title: Development and application of a rainfall-runoff model for semi-arid regions

description: ABSTRACT Despite the advances undertaken in recent years, modeling watershed’s hydrological responses remains a complex task, especially in data-scarce areas. In order to overcome this, new models with distinct representations of hydrological processes continue to be developed, incorporating spatial data and geoprocessing tools. In this article, the CAWM IV (Campus Agreste Watershed Model Version IV) model is presented. It is a conceptual model developed with the purpose of contributing mainly to the hydrological modeling of basins inserted in semi-arid regions. The article provides the layout of the mathematical model structure and a set of results obtained from the application of the model to basins with different characteristics. The main features of the model are the reduced number of parameters to calibrate and the incorporation of the basin physical characteristics in the calculation of several attributes, in order to facilitate the process of regionalization for other similar basins, particularly due to the absence of flow data. The CAWM IV model was applied to four basins located in the state of Pernambuco, in the Northeast region of Brazil. The model presented adequate behavior for 55 to 92% of the simulated events, depending on the criteria of performance indicators used in the analysis.
DOI: 10.6084/m9.figshare.12210545.v1
title: Development and application of a rainfall-runoff model for semi-arid regions

description: ABSTRACT Despite the advances undertaken in recent years, modeling watershed’s hydrological responses remains a complex task, especially in data-scarce areas. In order to overcome this, new models with distinct representations of hydrological processes continue to be developed, incorporating spatial data and geoprocessing tools. In this article, the CAWM IV (Campus Agreste Watershed Model Version IV) model is presented. It is a conceptual model developed with the purpose of contributing mainly to the hydrological modeling of basins inserted in semi-arid regions. The article provides the layout of the mathematical model structure and a set of results obtained from the application of the model to basins with different characteristics. The main features of the model are the reduced number of parameters to calibrate and the incorporation of the basin physical characteristics in the calculation of several attributes, in order to facilitate the process of regionalization for other similar basins, particularly due to the absence of flow data. The CAWM IV model was applied to four basins located in the state of Pernambuco, in the Northeast region of Brazil. The model presented adequate behavior for 55 to 92% of the simulated events, depending on the criteria of performance indicators used in the analysis.
DOI: 10.6084/m9.figshare.12210626
title: Effects of an array of widely separated vertical cylinders on time-averaged properties of progressive monochromatic waves

description: ABSTRACT The design of monopile foundations for offshore wind farms, the estimate of wave loads, and the effect of the structures on the environment usually consider one single vertical cylinder. This choice is based on the size of the ratio cylinder diameter to wavelength, and on the large distances between turbines. However, for large arrays of monopiles, the ensemble effect must be investigated. This study addresses monochromatic wave propagation through a rectangular array of four cylinders 800 m and 300 m apart, considered here as the fundamental geometry for an arbitrary array of monopiles turbines. Results for bottom velocities, mean water level, mass transport, and radiation stress tensor in the presence of the array are compared with those for a single cylinder. The numerical model WAMIT® is used to compute the potential velocity solution. Relevant spatial variations were found, especially for radiation stresses, for different periods and directions of propagation. Diffraction effects on the wave field by the array are significantly stronger than the superposition of individual effects of isolated cylinders under the same conditions. Impacts of the entire wind farm on bottom morphodynamics near the foundations, on the design loads, and on the wave climate past the wind farm are discussed.
DOI: 10.6084/m9.figshare.14270150
title: Methodology for physical modeling of reservoir sedimentation

description: RESUMO Reservatórios construídos em cursos d’água estão sujeitos a algum grau de assoreamento. Por isso, é importante a estimativa do volume de sedimentos acumulados, visto que esse depósito pode interferir nas funções do reservatório. Uma forma de se fazer isso é utilizando modelos físicos. Entretanto, a partir da literatura existente na área não é possível responder a algumas questões metodológicas que surgem em uma simulação física do assoreamento, como: qual vazão e descarga sólida utilizar? Simular um hidrograma ou uma vazão constante? Assim, esse trabalho teve como objetivo propor uma metodologia de simulação do assoreamento em modelos físicos, de forma que ao se utilizar essa metodologia o assoreamento observado no modelo reduzido pudesse representar o do protótipo. A partir de simulações numéricas e experimentais, optou-se por simular no modelo físico as vazões médias das ondas que compreendiam as vazões máximas. O tempo de escoamento de cada vazão foi de 30 minutos e as descargas sólidas totais utilizadas foram às referentes às vazões médias anuais. Utilizando-se essa metodologia, promoveu-se a simulação do assoreamento no modelo reduzido para o período entre 2013 e 2017, sendo que o resultado obtido foi próximo ao do protótipo, o que indica que a metodologia proposta permitiu representar no modelo reduzido o fenômeno do assoreamento ocorrido no reservatório real.
DOI: 10.6084/m9.figshare.14270150.v1
title: Methodology for physical modeling of reservoir sedimentation

description: RESUMO Reservatórios construídos em cursos d’água estão sujeitos a algum grau de assoreamento. Por isso, é importante a estimativa do volume de sedimentos acumulados, visto que esse depósito pode interferir nas funções do reservatório. Uma forma de se fazer isso é utilizando modelos físicos. Entretanto, a partir da literatura existente na área não é possível responder a algumas questões metodológicas que surgem em uma simulação física do assoreamento, como: qual vazão e descarga sólida utilizar? Simular um hidrograma ou uma vazão constante? Assim, esse trabalho teve como objetivo propor uma metodologia de simulação do assoreamento em modelos físicos, de forma que ao se utilizar essa metodologia o assoreamento observado no modelo reduzido pudesse representar o do protótipo. A partir de simulações numéricas e experimentais, optou-se por simular no modelo físico as vazões médias das ondas que compreendiam as vazões máximas. O tempo de escoamento de cada vazão foi de 30 minutos e as descargas sólidas totais utilizadas foram às referentes às vazões médias anuais. Utilizando-se essa metodologia, promoveu-se a simulação do assoreamento no modelo reduzido para o período entre 2013 e 2017, sendo que o resultado obtido foi próximo ao do protótipo, o que indica que a metodologia proposta permitiu representar no modelo reduzido o fenômeno do assoreamento ocorrido no reservatório real.
DOI: 10.6084/m9.figshare.14329089.v1
title: Comparative study between turbulence models in curved channels

description: ABSTRACT This paper presents a comparative study between results obtained in two-dimensional computational simulations performed with three different turbulence models: constant viscosity; Elder Model and k˗Ꜫ Model. The simulations were performed using the software Telemac 2D. These results were compared to data obtained from a study in experimental channel with trapezoidal cross-section and composed of straight stretches and curves. The main objective of this comparison is to explore how turbulence models affect the general behavior of the simulated flow. To support these comparisons, statistical analysis were adopted to quantify the differences between the velocity fields obtained in the simulations and that observed in the experimental channel. The results showed that, despite the theoretical limitations, the use of the simpler turbulence closure model, that is the constant turbulent viscosity, can lead to results as good as or better than those obtained with more sophisticated models.
DOI: 10.6084/m9.figshare.14329089
title: Comparative study between turbulence models in curved channels

description: ABSTRACT This paper presents a comparative study between results obtained in two-dimensional computational simulations performed with three different turbulence models: constant viscosity; Elder Model and k˗Ꜫ Model. The simulations were performed using the software Telemac 2D. These results were compared to data obtained from a study in experimental channel with trapezoidal cross-section and composed of straight stretches and curves. The main objective of this comparison is to explore how turbulence models affect the general behavior of the simulated flow. To support these comparisons, statistical analysis were adopted to quantify the differences between the velocity fields obtained in the simulations and that observed in the experimental channel. The results showed that, despite the theoretical limitations, the use of the simpler turbulence closure model, that is the constant turbulent viscosity, can lead to results as good as or better than those obtained with more sophisticated models.