cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.7515062
title: Occurrence and risk assessment of parabens and triclosan in surface waters of southern Brazil: a problem of emerging compounds in an emerging country

description: ABSTRACT Parabens and triclosan compounds are widely used in pharmaceutical products, personal care, food and various products of daily use. After use, the final destinations of these contaminants are domestic effluents and the environment if not collected or treated. The objective of this study was to evaluate the presence of parabens and triclosan in environments in a subtropical region, more specifically in the metropolitan region of Curitiba (southern Brazil) and possible effects of these compounds in aquatic environments through risk assessment through the use of risk quotient (RQ). Samples were collected in 20 points for 4 campaigns. For the extraction of the compounds we used the extraction technique of solid phase extraction (SPE). The determination of the compounds was using gas chromatography coupled to mass spectrometry (GC-MS). It was observed high concentrations of parabens, especially MeP (up to 2875 ng L–1). Despite high concentrations of parabens, their presence has a low risk to aquatic organisms. Triclosan has been observed at higher concentrations (415 ng L–1), suggesting once again that these environments are impacted by human action. The RQ assessed that triclosan has a high risk for certain groups of organisms.
DOI: 10.6084/m9.figshare.7515062.v1
title: Occurrence and risk assessment of parabens and triclosan in surface waters of southern Brazil: a problem of emerging compounds in an emerging country

description: ABSTRACT Parabens and triclosan compounds are widely used in pharmaceutical products, personal care, food and various products of daily use. After use, the final destinations of these contaminants are domestic effluents and the environment if not collected or treated. The objective of this study was to evaluate the presence of parabens and triclosan in environments in a subtropical region, more specifically in the metropolitan region of Curitiba (southern Brazil) and possible effects of these compounds in aquatic environments through risk assessment through the use of risk quotient (RQ). Samples were collected in 20 points for 4 campaigns. For the extraction of the compounds we used the extraction technique of solid phase extraction (SPE). The determination of the compounds was using gas chromatography coupled to mass spectrometry (GC-MS). It was observed high concentrations of parabens, especially MeP (up to 2875 ng L–1). Despite high concentrations of parabens, their presence has a low risk to aquatic organisms. Triclosan has been observed at higher concentrations (415 ng L–1), suggesting once again that these environments are impacted by human action. The RQ assessed that triclosan has a high risk for certain groups of organisms.
DOI: 10.6084/m9.figshare.7514429.v1
title: Influence of oceanic-atmospheric interactions on extreme events of daily rainfall in the Sub-basin 39 located in Northeastern Brazil

description: ABSTRACT Changes in extreme precipitation have been observed in regions where frequent rainfalls occur over short periods of time followed by prolonged droughts, creating, as a result, new watershed scenarios. Recent studies have attributed such occurrences to possible climate changes. This paper analyzes the correlation between extreme events recorded in the Sub-basin 39, located in Northeastern Brazil, and the anomalies caused by sea surface temperature - SST and the atmospheric systems operating in the region. Pearson correlation coefficients have been used combined with the variables analyzed. For such, trends in precipitation have been obtained by using the method of least squares together with linear regression and the Student's t test. The results obtained have demonstrated that due to the geographical position of the region investigated, both maximum extreme events (areas with positive trends) and minimum extreme events (areas with negative trends) are more dependent on the Dipole Atlantic than on the effects of El Niño Southern Oscillation - ENOS.
DOI: 10.6084/m9.figshare.7514429
title: Influence of oceanic-atmospheric interactions on extreme events of daily rainfall in the Sub-basin 39 located in Northeastern Brazil

description: ABSTRACT Changes in extreme precipitation have been observed in regions where frequent rainfalls occur over short periods of time followed by prolonged droughts, creating, as a result, new watershed scenarios. Recent studies have attributed such occurrences to possible climate changes. This paper analyzes the correlation between extreme events recorded in the Sub-basin 39, located in Northeastern Brazil, and the anomalies caused by sea surface temperature - SST and the atmospheric systems operating in the region. Pearson correlation coefficients have been used combined with the variables analyzed. For such, trends in precipitation have been obtained by using the method of least squares together with linear regression and the Student's t test. The results obtained have demonstrated that due to the geographical position of the region investigated, both maximum extreme events (areas with positive trends) and minimum extreme events (areas with negative trends) are more dependent on the Dipole Atlantic than on the effects of El Niño Southern Oscillation - ENOS.
DOI: 10.6084/m9.figshare.7508147
title: Performance evaluation of optimization models in the determination of wastewater treatment efficiencies inside watersheds

description: ABSTRACT Determination of sewage treatment plants pollutant removal efficiencies, considering the protection of water resources, is very difficult because it involves complex analysis that must take into account multiple discharges into watercourses presenting different self depuration capacities. The research aimed to evaluate different optimization models for determination of minimum sewage treatment efficiencies for plants located in a watershed. The analyzed optimization models involves minimization of the sum of treatment efficiencies and minimization of inequity between sewage treatment efforts. Water quality mathematical model and Genetic Algorithm were combined in a MatLab software computing environment. The Pardo river watershed is the study area. Pardo river is a tributary of the Itapemirim river, important watercourse located in the southern part of Espirito Santo State, in Brazil. The results indicate that the optimization models that incorporate measurement of equity as a problem restriction did not generate consistent answers, probably because of the wide range of sewage loads values considered in the Pardo river watershed. The models that incorporate equity measures in the objective function showed satisfactory performance and resulted in very close values for minimum sewage treatment efficiencies.
DOI: 10.6084/m9.figshare.7508147.v1
title: Performance evaluation of optimization models in the determination of wastewater treatment efficiencies inside watersheds

description: ABSTRACT Determination of sewage treatment plants pollutant removal efficiencies, considering the protection of water resources, is very difficult because it involves complex analysis that must take into account multiple discharges into watercourses presenting different self depuration capacities. The research aimed to evaluate different optimization models for determination of minimum sewage treatment efficiencies for plants located in a watershed. The analyzed optimization models involves minimization of the sum of treatment efficiencies and minimization of inequity between sewage treatment efforts. Water quality mathematical model and Genetic Algorithm were combined in a MatLab software computing environment. The Pardo river watershed is the study area. Pardo river is a tributary of the Itapemirim river, important watercourse located in the southern part of Espirito Santo State, in Brazil. The results indicate that the optimization models that incorporate measurement of equity as a problem restriction did not generate consistent answers, probably because of the wide range of sewage loads values considered in the Pardo river watershed. The models that incorporate equity measures in the objective function showed satisfactory performance and resulted in very close values for minimum sewage treatment efficiencies.
DOI: 10.6084/m9.figshare.7508765
title: Estimation and uncertainty of remote-sensing-based Depth-Area-Volume (DAV) relationships

description: ABSTRACT Artificial reservoirs are the only reliable source of water resources in most of the brazilian semiarid region. Their water availability depends on the hydrology and the climate, but also on the geometry of the reservoir, expressed usually in terms of Depth-Area-Volume (DAV) curves. However, for most public reservoirs in northeastern Brazil, this information is often outdated or inconsistent, because of reservoir silting and the lack of systematic updating and assessment of actual storage capacity. . In this work, we present a quick and low-cost statistical procedure to assess reservoir volume, based on temporal sequences of satellite imagery and water level monitoring. Two methods are evaluated to quantify the confidence intervals from these estimates. The results were validated for a reservoir where a recent and reliable bathymetry is available. The approach was then used to estimate the volume of a reservoir in northern Minas Gerais, which storage capacity is uncertain.
DOI: 10.6084/m9.figshare.7508765.v1
title: Estimation and uncertainty of remote-sensing-based Depth-Area-Volume (DAV) relationships

description: ABSTRACT Artificial reservoirs are the only reliable source of water resources in most of the brazilian semiarid region. Their water availability depends on the hydrology and the climate, but also on the geometry of the reservoir, expressed usually in terms of Depth-Area-Volume (DAV) curves. However, for most public reservoirs in northeastern Brazil, this information is often outdated or inconsistent, because of reservoir silting and the lack of systematic updating and assessment of actual storage capacity. . In this work, we present a quick and low-cost statistical procedure to assess reservoir volume, based on temporal sequences of satellite imagery and water level monitoring. Two methods are evaluated to quantify the confidence intervals from these estimates. The results were validated for a reservoir where a recent and reliable bathymetry is available. The approach was then used to estimate the volume of a reservoir in northern Minas Gerais, which storage capacity is uncertain.
DOI: 10.6084/m9.figshare.7515668
title: Using hydrodynamic model for flow calculation from level measurements

description: ABSTRACT The use of hydrodynamic models to determine stream discharges has been grown in recent years due to the problems regarding the use of rating curve method for discharge estimating. This study aims to develop a method for determining discharges in open channels using multiobjective evolutionary algorithms (NSGA-II) and free surface level measurements associated with a hydrodynamic model. Data obtained from experiments on a laboratory experimental channel have been used for model calibration and validation. NSGA-II optimization algorithm presented excellent results and Nash-Sutcliffe coefficients greater than 0.99 have been obtained for both calibration and validation of the hydrodynamic model. Discharges calculated by the hydrodynamic model showed variations of up to 150% for the same level when compared to the discharges estimated by the rating curve, which showed that the use of rating curve for discharge measurements during transient flows results in high errors.
DOI: 10.6084/m9.figshare.7515668.v1
title: Using hydrodynamic model for flow calculation from level measurements

description: ABSTRACT The use of hydrodynamic models to determine stream discharges has been grown in recent years due to the problems regarding the use of rating curve method for discharge estimating. This study aims to develop a method for determining discharges in open channels using multiobjective evolutionary algorithms (NSGA-II) and free surface level measurements associated with a hydrodynamic model. Data obtained from experiments on a laboratory experimental channel have been used for model calibration and validation. NSGA-II optimization algorithm presented excellent results and Nash-Sutcliffe coefficients greater than 0.99 have been obtained for both calibration and validation of the hydrodynamic model. Discharges calculated by the hydrodynamic model showed variations of up to 150% for the same level when compared to the discharges estimated by the rating curve, which showed that the use of rating curve for discharge measurements during transient flows results in high errors.
DOI: 10.6084/m9.figshare.7509224.v1
title: Public participation for bulk water charge: Paraíba River Basin Committee (Brazil) and Alentejo Hydrographic Region Council (Portugal) cases study

description: ABSTRACT This paper proposes to assess the knowledge and dynamics of Committees/Councils in the discussions and deliberations on the raw water charges in Brazil and in Portugal. The comparison is limited to the evaluation of a Committee and Council and not necessarily reflect the operation of other CBHs, in Brazil, or Councils, in Portugal. It was analyzed the minutes of the meetings of the Paraíba River Basin Committee (CBH-PB) and the Alentejo River Basin Council Region (CRH-Alentejo) as well as interviews with members of the two collective bodies. For the Brazilian case, it appears that CBH-PB members discussed and deliberated on the values and mechanisms for raw water charges. In Portugal, the definition of values and the way of application of the raw water charge (TRH) was held at the central level, without the CRH-Alentejo having the opportunity to argue, not fulfilling its role as a consultative body water management. Water Resources Policies have to gain strength by promoting public participation through discussion formats and being able to engage key stakeholders as well as creating conditions for the development of cooperative relations.
DOI: 10.6084/m9.figshare.7509224
title: Public participation for bulk water charge: Paraíba River Basin Committee (Brazil) and Alentejo Hydrographic Region Council (Portugal) cases study

description: ABSTRACT This paper proposes to assess the knowledge and dynamics of Committees/Councils in the discussions and deliberations on the raw water charges in Brazil and in Portugal. The comparison is limited to the evaluation of a Committee and Council and not necessarily reflect the operation of other CBHs, in Brazil, or Councils, in Portugal. It was analyzed the minutes of the meetings of the Paraíba River Basin Committee (CBH-PB) and the Alentejo River Basin Council Region (CRH-Alentejo) as well as interviews with members of the two collective bodies. For the Brazilian case, it appears that CBH-PB members discussed and deliberated on the values and mechanisms for raw water charges. In Portugal, the definition of values and the way of application of the raw water charge (TRH) was held at the central level, without the CRH-Alentejo having the opportunity to argue, not fulfilling its role as a consultative body water management. Water Resources Policies have to gain strength by promoting public participation through discussion formats and being able to engage key stakeholders as well as creating conditions for the development of cooperative relations.
DOI: 10.6084/m9.figshare.7516133.v1
title: Hydrological system time lag responses to meteorological shifts

description: ABSTRACT Hydrological system’s sensibility and resilience to dry periods are crucial for estimating the potential impacts of droughts. Quantifying response times (RT) of this system’s components relative to droughts allows one to develop a predictive understanding of future impacts. In this context, this study proposes the use of non-parametric statistical methods to estimate RT between meteorological shifts, given by the Standardized Precipitation Index (SPI), and the respective changes in the hydrological system, measured by river discharge (Q) and reservoir storage time series. Change point (CP) analyses were applied to time series of (i) SPI and accumulated storage relative to 32 reservoirs within the Paraná basin; and (ii) SPI, Q and reservoir storage relative to Furnas hydroelectric power plant. Based on the responses from CP analyses, RT in case (i) varied from 0 – 6 months, whereas, in case (ii), results indicate that significant changes in Q occurred in the same month of changes in rainfall. Results also suggest a minor role of anthropogenic factors (dam operation) compared to natural forcing in reservoir depletion during the 2014 drought than that in 2000/2001. This study reinforces the importance of an optimized reservoir management, considering the balance between anthropogenic and natural forcing as a strategy to combat droughts impacts.
DOI: 10.6084/m9.figshare.7516133
title: Hydrological system time lag responses to meteorological shifts

description: ABSTRACT Hydrological system’s sensibility and resilience to dry periods are crucial for estimating the potential impacts of droughts. Quantifying response times (RT) of this system’s components relative to droughts allows one to develop a predictive understanding of future impacts. In this context, this study proposes the use of non-parametric statistical methods to estimate RT between meteorological shifts, given by the Standardized Precipitation Index (SPI), and the respective changes in the hydrological system, measured by river discharge (Q) and reservoir storage time series. Change point (CP) analyses were applied to time series of (i) SPI and accumulated storage relative to 32 reservoirs within the Paraná basin; and (ii) SPI, Q and reservoir storage relative to Furnas hydroelectric power plant. Based on the responses from CP analyses, RT in case (i) varied from 0 – 6 months, whereas, in case (ii), results indicate that significant changes in Q occurred in the same month of changes in rainfall. Results also suggest a minor role of anthropogenic factors (dam operation) compared to natural forcing in reservoir depletion during the 2014 drought than that in 2000/2001. This study reinforces the importance of an optimized reservoir management, considering the balance between anthropogenic and natural forcing as a strategy to combat droughts impacts.
DOI: 10.21227/n1q3-s890
title: Day-Ahead Forecasting using LSTM with rolling windows

description: The project involves day-ahead forecasting which takes a model fit into historical data and predicts future demand of electricity. Time series forecasting methods are used as the dataset contains an explicit order dependence between observations, i.e. a time dimension which makes the problem difficult to handle but makes the prediction more accurate. Various machine learning and deep learning algorithms were used to accomplish this work. Results obtained by autoregressive integrated moving average(ARIMA), autoregressive moving average with explanatory variable(ARIMAX), seasonal autoregressive moving average(SARIMA), seasonal autoregressive moving average(SARIMAX) and long short term memory(LSTM) recurrent neural networks with rolling windows were compared and the one with least error, i.e. LSTM with rolling windows was used for time series prediction.
DOI: 10.6084/m9.figshare.7507559.v1
title: Analysis of the hydraulic behavior of a vertical slot fishway in two slopes

description: ABSTRACT Several fish transposition systems (MTP´s) have been employed to allow the fish upstream migration through river dams for spawning. The design of MTP´s of the type of vertical slot fishways requires not only the analysis of the pool hydraulic behavior to evaluate the velocity fields, the energy dissipation levels, and the Reynolds shear stress distributions, but also the study of biological characteristics of aquatic species impacted by the river dams. However, these parameters are not evaluated together, and some of them are valued at the average of the tank. This work deals with an analysis of the main hydraulic characteristics of a slot vertical fishway at two channel slopes, 6% and 12%. The hydraulic characteristic graphs obtained in this work show that a slope of 6% is preferable for the design of this kind of fishway, since the associated velocity magnitudes fits better to the ideal conditions for the safe fish passage. The slope of 12% creates restrictions in terms of the available area for fish passage due to power dissipation and shear stresses conditions.
DOI: 10.6084/m9.figshare.7507559
title: Analysis of the hydraulic behavior of a vertical slot fishway in two slopes

description: ABSTRACT Several fish transposition systems (MTP´s) have been employed to allow the fish upstream migration through river dams for spawning. The design of MTP´s of the type of vertical slot fishways requires not only the analysis of the pool hydraulic behavior to evaluate the velocity fields, the energy dissipation levels, and the Reynolds shear stress distributions, but also the study of biological characteristics of aquatic species impacted by the river dams. However, these parameters are not evaluated together, and some of them are valued at the average of the tank. This work deals with an analysis of the main hydraulic characteristics of a slot vertical fishway at two channel slopes, 6% and 12%. The hydraulic characteristic graphs obtained in this work show that a slope of 6% is preferable for the design of this kind of fishway, since the associated velocity magnitudes fits better to the ideal conditions for the safe fish passage. The slope of 12% creates restrictions in terms of the available area for fish passage due to power dissipation and shear stresses conditions.
DOI: 10.6084/m9.figshare.7510703
title: Effect of the Cantareira System on the flow regime in Piracicaba River basin

description: ABSTRACT The large reservoirs operation can change all the natural fluvial dynamics of a river, requiring a better understanding about the influences of these interferences to an appropriate management, minimizing negative impacts. Faced with this, the aim in this paper was to identify the alterations in the flow regime of the main rivers of Piracicaba River basin, mainly due to the implementation of Cantareira System reservoirs. The analyzes were based on the average daily flow series from four fluviometric stations in the rivers Atibaia and Jaguari and Piracicaba (influenced by Cantareira System) and Camanducaia (in the same basin but without influence from Cantareira System), for comparison, using the IHA (Indicators of Hydrologic Alteration) software, which calculates the hydrological alteration factors of the 33 hydrological parameters ecologically relevant, that characterizes the magnitude, timing, frequency, duration and rate of flow change. For the rivers influenced by Cantareira System was observed that from the 1970s and 1980s, overall, there was a decrease in the mean flow, approximately 24% in Atibaia River, 50% in Jaguari River, and 14% in Piracicaba River, where in the decrease in the flows was mainly in the dry season (April to September), besides a decrease in the median of the annual seven days minimum flows by 25% and 56% and 15%, respectively. There also an increase in the frequency and duration of the lower flows and a decrease in the duration of high flows. The most significant changes occurred in Jaguari River, followed by the Atibaia River and were less significant in the Piracicaba River, which is the farthest from the reservoirs. For the Camanducaia River, after the 1970s, there was no change in the median of the annual seven days minimum flows and it was observed, overall, an increase in the mean flow by 21%, as well as an increase in the frequency of the maximum flows. However, the changes were not as significant as in the others rivers.