Person:
Avilés Añazco, Alex Manuel

Birth Date

1977-04-03

ORCID

0000-0001-9278-5738

Scopus Author ID

56511440200

Afiliación

Universidad de Cuenca, Cuenca, Ecuador
Universidad de Cuenca, Departamento de Química Aplicada y Sistemas de Producción, Cuenca, Ecuador
Universidad de Cuenca, Grupo de Evaluación de Riesgos Ambientales en Sistemas de Producción y Servicios (RISKEN), Cuenca, Ecuador

País

Ecuador

Organizational Units

Organizational Unit

Facultad de Ciencias Químicas

Fundada en 1955 como la Escuela de Química Industrial, la facultad ha sido un pilar fundamental en la formación de profesionales altamente capacitados, comprometidos con el desarrollo de la ciencia, la educación y el bienestar social. La Facultad de Ciencias Químicas pone a consideración su trabajo académico, investigativo y de vinculación con la sociedad, desarrollado a través de la práctica de una docencia de calidad, investigación e innovación en su área de estudio. Desde su oficio de conocimiento se permite contribuir a la sociedad con cuatro carreras: Bioquímica y Farmacia, Ingeniería Química, Ingeniería Ambiental e Ingeniería Industrial. Su carta de presentación en la Academia, la coloca como una dependencia dinámica, donde confluye la solidez de una trayectoria de más de sesenta años. Aquí se trabaja en una continua formación de pregrado y posgrado de la más alta calidad, mediante la mejora continua con la innovación y a la vanguardia de las ciencias químicas.

Job Title

Profesor (T)

Last Name

Avilés Añazco

First Name

Alex Manuel

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Now showing 1 - 10 of 25

Integrated methodological framework for assessing the risk of failure in water supply incorporating drought forecasts. Case study: andean regulated river basin
(2018) Avilés Añazco, Alex Manuel; Solera Solera, Abel; Paredes Arquiola,, Javier; Pedro Monzonís, María
Hydroclimatic drought conditions can affect the hydrological services offered by mountain river basins causing severe impacts on the population, becoming a challenge for water resource managers in Andean river basins. This study proposes an integrated methodological framework for assessing the risk of failure in water supply, incorporating probabilistic drought forecasts, which assists in making decisions regarding the satisfaction of consumptive, non-consumptive and environmental requirements under water scarcity conditions. Monte Carlo simulation was used to assess the risk of failure in multiple stochastic scenarios, which incorporate probabilistic forecasts of drought events based on a Markov chains (MC) model using a recently developed drought index (DI). This methodology was tested in the Machangara river basin located in the south of Ecuador. Results were grouped in integrated satisfaction indexes of the system (DSIG). They demonstrated that the incorporation of probabilistic drought forecasts could better target the projections of simulation scenarios, with a view of obtaining realistic situations instead of optimistic projections that would lead to riskier decisions. Moreover, they contribute to more effective results in order to propose multiple alternatives for prevention and/or mitigation under drought conditions.
Performance of Phragmites Australis and Cyperus Papyrus in the treatment of municipal wastewater by vertical flow subsurface constructed wetlands
(2019) Avilés Añazco, Alex Manuel; García Ávila, Fausto Fernando; Zhinin Chimbo, Fanny Lucia; Donoso Moscoso, Silvana Patricia; Flores del Pino, Lisveth; Patiño Chavez, Jhanina Fabiola
The use of constructed wetlands to treat municipal wastewater reduces energy consumption and therefore economic costs, as well as reduces environmental pollution. The purpose of this study was to compare the purification capacity of domestic wastewater using two species of plants sown in subsurface constructed wetlands with vertical flow built on a small scale that received municipal wastewater with primary treatment. The species used were Phragmites Australis and Cyperus Papyrus. For this purpose, a constant flow of 0.6 m3 day−1 was fed from the primary lagoon to each of the two wetlands built on a pilot scale with continuous flow. Each unit was filled with granite gravel in the lower part and with silicic sand in the upper part of different granulometry, the porosity of the medium was 0.34, with a retention time of 1.12 days and a hydraulic load rate of 0.2 m day−1. To analyze the purification capacity of wastewater, physical, chemical and biological parameters were monitored during three months. Samples were taken at the entrance and exit in each experimental unit. The results obtained in the experimental tests for the two species of plants, indicated that the Cyperus Papyrus presented a greater capacity of pollutants removal as biochemical oxygen demand (80.69%), chemical oxygen demand (69.87%), ammoniacal nitrogen (69.69%), total phosphorus (50%), total coliforms (98.08%) and fecal coliforms (95.61%). In the case of Phragmites Australis retains more solids. The species with greater efficiency in the treatment of municipal wastewater for this study was Cyperus Papyrus. Keywords: Constructed wetland, Fitorremediacion, Macrophytes, Nutrients, Wastewater treatment
Probabilistic forecasting of drought events using Markov chain- and Bayesian network-based models: A case study of an Andean regulated river basin
(MDPI AG, 2016-01-01) Avilés Añazco, Alex Manuel; Célleri Alvear, Rolando Enrique
The scarcity of water resources in mountain areas can distort normal water application patterns with among other effects, a negative impact on water supply and river ecosystems. Knowing the probability of droughts might help to optimize a priori the planning and management of the water resources in general and of the Andean watersheds in particular. This study compares Markov chain- (MC) and Bayesian network- (BN) based models in drought forecasting using a recently developed drought index with respect to their capability to characterize different drought severity states. The copula functions were used to solve the BNs and the ranked probability skill score (RPSS) to evaluate the performance of the models. Monthly rainfall and streamflow data of the Chulco River basin, located in Southern Ecuador, were used to assess the performance of both approaches. Global evaluation results revealed that the MC-based models predict better wet and dry periods, and BN-based models generate slightly more accurately forecasts of the most severe droughts. However, evaluation of monthly results reveals that, for each month of the hydrological year, either the MC- or BN-based model provides better forecasts. The presented approach could be of assistance to water managers to ensure that timely decision-making on drought response is undertaken.
Evaluación de métodos de relleno para series temporales de precipitación y temperatura diarias: el caso de los Andes ecuatorianos
(2014) Samaniego Alvarado, Esteban Patricio; Campozano Parra, Lenin Vladimir; Sánchez Cordero, Esteban Remigio; Avilés Añazco, Alex Manuel
Continuous time series of precipitation and temperature considerably facilitate and improve the calibration and validation of climate and hydrologic models, used inter alia for the planning and management of earth’s water resources and for the prognosis of the possible effects of climate change on the rainfall-runoff regime of basins. The goodness-of-fit of models is among other factors dependent from the completeness of the time series data. Particular in developing countries gaps in time series data are very common. Since gaps can severely compromise data utility this research with application to the Andean Paute river basin examines the performance of 17 deterministic infill methods for completing time series of daily precipitation and mean temperature. Although sophisticated approaches for infilling gaps, such as stochastic or artificial intelligence methods exist, preference in this study was given to deterministic approaches for their robustness, easiness of implementation and computational efficiency. Results reveal that for the infilling of daily precipitation time series the weighted multiple linear regression method outperforms due to considering the ratio of the Pearson correlation coefficientto the distance, giving more weight to both, highly correlated and nearby stations. For mean temperature, the climatological mean of the day was clearly the best method, most likely due to the scarcity of weather stations measuring temperature, and because the few available stations are located at different elevations in the landscape, suggesting the need to address in future studies the impact of elevation on the interpolation.
Local rainfall modelling based on global climate information: a data-based approach
(2020) Mendoza Sigüenza, Daniel Emilio; Samaniego Alvarado, Esteban Patricio; Mora Serrano, Diego Esteban; Espinoza Mejía, Jorge Mauricio; Pacheco Tobar, Esteban Alonso; Avilés Añazco, Alex Manuel
Modelling climate is complex due to multi-scale interactions and strong nonlinearities. However, climate signals are typically quasi-periodical and are likely to depend on exogenous-variables. Motivated by this insight, we propose a strategy to circumvent modelling complexity based on the following ideas. 1) The observed signals can be decomposed into non-stationary trends and quasi-periodicities through Dynamic-Harmonic-Regressions (DHR). 2) The main-frequencies and decomposed signals can be used for constructing a harmonic model with varying parameters depending on exogenous-variables. 3) The State-Dependent-Parameter (SDP) technique allows for the dynamical estimation of these parameters. The resulting DHR-SDP combined approach is applied to rainfall- monthly modelling, using global-climate signals as exogenous-variables. As a result, 1) the model yields better predictions than standard alternative techniques; 2) the model is robust regarding data limitations and useful for several-steps-ahead forecasting; 3) interesting relations between global-climate states and the local rainfall’s sea- sonality are obtained from the SDP estimated functions.
Vertical tubular flocculator: alternative technology for the improvement of drinking water treatment processes in rural areas
(2023) Avilés Añazco, Alex Manuel; García Ávila, Fausto Fernando; Tenesaca Pintado, Darwin Adrian; Guanuchi Quito, Alexandra Elizabeth; Tonon Ordoñez, Maria Dolores; Novoa Zamora, Carlos Francisco
The guarantee of access to safe drinking water for rural communities is a great challenge due to the increase in contamination and deterioration of water sources. Rural areas face technological, financial, and operational limitations, having poor water quality, generally. The purpose of this study was to evaluate the efficiency of a vertical tubular flocculator (VTF) to be used as part of the purification process in rural areas where small flows are used. An experimental treatment system (ETS) implemented in the field was used. The VTF was implemented using PVC pipes and fittings. Tests were carried out with the same raw water used from a conventional treatment plant with aluminum sulfate as a coagulant. The optimal coagulant dose applied in the ETS was determined by the jar test. In the VTF, the length, turbidity, and flow of the raw water were varied. The hydraulic behaviour of the VTF was evaluated with the analysis of the time distribution curve of concentration of a tracer applying the Wolf-Resnick model. A low residence time VTF was obtained, representing a new efficient flocculation model for the reduction of turbidity and colour. The results showed that the turbidity of the raw water, the residence time, and the degree of agitation are important parameters in the operation and efficiency of a VTF. There was a predominance of plug flow in the reactor. The obtained results were compared with the efficiency of a conventional water treatment plant used in the study site. The results obtained indicated that this ETS that integrates a VTF with settling and filtration can be a useful tool for rural areas. It was recommended to replicate this study with wastewater, other dimensions of the VTF, to establish a specific methodology for the design of the VTF, to evaluate the dosage with dose bombs for improving the results of VTF, and to elaborate a hydraulic model for VTF
Pressure management for leakage reduction using pressure reducing valves. Case study in an Andean city
(2019) Avilés Añazco, Alex Manuel; Flores del Pino, Lisveth; Ramos Fernández, Lia; Guanuchi Quezada, Christian Marcelo; Garcíaa Ávila, Fausto Fernando
A very common problem in distribution systems is water leakage, which can be reduced by pressure management. The objective of this study was to evaluate the reduction of water leakage by optimizing the pressure using pressure reducing valves (PRV). The corresponding hydraulic model of a real distribution network was developed using the EPANET software. After the hydraulic model was calibrated and validated, the analysis of the pressure in the nodes, the velocity in the pipes, through the technical performance indicators (TPI) was performed, in addition, the leakages were quantified. The initial results indicated the need to optimize the pressure, nodes with excessive pressures were found in the lower part of the network. WaterNetGen was used as an extension of EPANET software to model leakages based on pressure after determining the leakage coefficient and considering the installation of two PRVs. The results allowed optimizing the appropriate pressure in 30.83% of the nodes and minimizing leakages in 31.65%. In turn, the simulation assuming the installation of two PRVs determined that the TPI would increase from 79.81% to 97.45%. The focus of this study is recommended to the companies that supply drinking water as a support tool for planning to reduce leakages.
Application of ornamental plants in constructed wetlands for wastewater treatment: A scientometric analysis
(2023) García Ávila, Fausto Fernando; Guanuchi Quito, Alexandra Elizabeth; Avilés Añazco, Alex Manuel
The application of ornamental plants in constructed wetlands (CW) is increasingly of interest to researchers, professionals actively involved in wetland management and/or wastewater treatment (WWT), so it is necessary to know the trends in this field of research. The objective of this study was to develop a scientometric study on the use of ornamental plants in CWs for the WWT during the period 2002–2022. For this, a search of the information was carried out in the Scopus database, including all the articles and reviews related to this field. The analysis of the recovered documents allowed to know key aspects of the evolution of production in recent years, the maturity of research in this field, identify the most used ornamental plants and therefore identify gaps. Likewise, it was possible to identify the countries, the most relevant authors, the main journals and the most cited articles through which knowledge in this area is disseminated. The results showed that Mexico, Brazil, USA, China and India have the highest number of publications related to the use of ornamental plants in the CWs. It was found that the most used ornamental plants are Canna, Iris, Heliconia and Zantedeschia. This analysis can help researchers to identify new research approaches in this field. It is concluded that this field of knowledge has aroused great interest since 2002; however, more research can still be carried out on the application of CWs with ornamental plants in cold climates, the influence of the substrate on the growth of these plants.
Future meteorological droughts in Ecuador: decreasing trends and associated spatio temporal features derived from CMIP5 models
(2020) Campozano Parra, Lenin Vladimir; Ballari, Daniela Elisabet; Montenegro Ambrosi, Martin Patricio; Avilés Añazco, Alex Manuel
Droughts are one of the most spatially extensive disasters that are faced by societies. Despite the urgency to define mitigation strategies, little research has been done regarding droughts related to climate change. The challenges are due to the complexity of droughts and to future precipitation uncertainty from Global Climate Models (GCMs). It is well-known that climate change will have more impact on developing countries. This is the case for Ecuador, which also has the additional challenges of lacking meteorological drought studies covering its three main regions: Coast, Highlands, and Amazon, and of having an intricate orography. Thus, this study assesses the spatio-temporal characteristics of present and future droughts in Ecuador under Representative Concentrations Pathways (RCP) 4.5 and 8.5. The 10 km dynamically downscaled products (DGCMs) from Coupled Model Intercomparison Project 5 (CMIP5) was used. The Standardized Precipitation Index (SPI) for droughts was calculated pixel-wise for present time 1981–2005 and for future time 2041-2070. The results showed a slightly decreasing trend for future droughts for the whole country, with a larger reduction for moderate droughts, followed by severe and extreme drought events. In the Coast and Highland regions, the intra-annual analysis showed a reduction of moderate and severe future droughts for RCP 4.5 and for RCP 8.5 throughout the year. Extreme droughts showed small and statistically non-significant decreases. In the Amazon region, moderate droughts showed increases from May to October, and decreases for the rest of the year. Additionally, severe drought increases are expected from May to December, and decreases from January to April. Finally, extreme drought increases are expected from January to April, with larger increases in October and November. Thus, in the Amazon, the rainy period showed a decreasing trend of droughts, following the wetter in wet- and drier in dry paradigm. Climate change causes decision-making process and calls for adaptation strategies being more challenging. In this context, our study has contributed to better mapping the space-time evolution of future drought risk in Ecuador, thus providing valuable information for water management and decision making as Ecuador faces climate change. © Copyright © 2020 Campozano, Ballari, Montenegro and Avilés.
Evaluation of Markov Chain Based Drought Forecasts in an Andean Regulated River Basin Using the Skill Scores RPS and GMSS
(KLUWER ACADEMIC PUBLISHERS, 2015-01-01) Avilés Añazco, Alex Manuel; Célleri Alvear, Rolando Enrique
On behalf of the decision-makers of Andean regulated river basins a drought index was developed to predict the occurrence and extent of drought events. Two stochastic models, the Markov Chain First Order (MCFO) and the Markov Chain Second Order (MCSO) model, predicting the frequency of monthly droughts were applied and the performance checked using two skill scores, respectively the ranked probability score (RPS) and the Gandin-Murphy skill score (GMSS). Data of the Chulco River basin (3200–4300 m.a.s.l.), situated in the Ecuadorian southern Andes, were employed to test the performance of both models. Results indicate that events with greater drought severity were more accurately predicted. The study also revealed the importance of verifying the quality of the forecasts and to have an assessment of the likely performance of the forecasting models before adopting any model and accepting the resulting information for decision-making.