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

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.
Sensitivity exploration of water balance in scenarios of future changes: a case study in an andean regulated river basin
(2020) Avilés Añazco, Alex Manuel; Palacios Garate, Karina Fernanda; Pacheco Nivelo, Jheimy Lorena; Jimenez Yucta, Stalin Daniel; Zhiña Villa, Dario Xavier; Delgado Inga, Victor Omar
Effects of climate change on water resources availability have been studied extensively; however, few studies have explored the sensitivity of water to several factors of change. This study aimed to explore the sensitive of water balance in water resources systems due to future changes of climate, land use and water use. Dynamical and statistical downscaling were applied to four global climate models for the projections of precipitation and temperature of two climate scenarios RCP 4.5 and RCP 8.5. Land use projections were carried out through a combination of Markov chains and cellular automata methods. These projections were introduced in a hydrologic model for future water supply evaluation, and its interactions with water use projections derived from a statistical analysis which served to assessment deficits and surplus in water to 2050. This approach was applied in the Machángara river basin located in the Ecuadorian southern Andes. Results showed that the water supply exceeds the water demand in most scenarios; however, taking into account the seasonality, there were months like August and January that would have significant water deficit in joint scenarios in the future. These results could be useful for planners formulating actions to achieve water security for future generations.
Extreme rainfall variations under climate change scenarios. Case of study in an andean tropical river basin
(2022) Avilés Añazco, Alex Manuel; Montenegro Ambrosi, Martin Patricio; Mendoza Sigüenza, Daniel Emilio; Mora Serrano, Diego Esteban; García Ávila, Fausto Fernando
Maximum rainfall events have triggered hazards that harm ecosystems and populations. Climate change could modify these extreme events, becoming more severe and frequent. Knowing the patterns of Spatio-temporal changes in the distribution of extreme rainfall in Andean regions represents a research challenge due to the complex climate behavior in the tropical mountain basins. The study aimed to analyze future Spatio-temporal changes in maximum daily rainfall patterns. The methods and analysis were performed in the Paute river basin in Ecuador through observed and simulated data from 1985 to 2005. The outputs of an ensemble regional climate model of Ecuador (RCM) based on CMIP5 models were used with two representative concentrations pathways (RCP), scenarios 4.5 and 8.5, in two future periods; future 1 from 2011 to 2040 and future 2 from 2041 to 2070. The General Extreme Value (GEV) distribution was used to fit the maximum annual daily rainfall. The maximum rainfall change factor between historical and future periods was calculated for 5,10,30, 60, and 100 years return periods. The results showed an increment of maximum rainfall spatial average in all return periods for RCP 4.5 and 8.5 in the future 1. Future 2 presented an increment of maximum rainfall spatial average in all return periods for RCP 4.5 and 8.5 scenarios except for the 30,60 and 100 years return periods of the RCP 4.5 scenario, displaying a decrease of maximum rainfall spatial average. Knowing rainfall pattern projections could help formulate actions to diminish the risks of extreme rainfall.
Modeling of residual chlorine in a drinking water network in times of pandemic of the SARS-CoV-2 (COVID-19)
(2021) García Ávila, Fausto Fernando; Avilés Añazco, Alex Manuel; Ordoñez Jara, Juan Andres; Guanuchi Quezada, Christian Marcelo; Flores del Pino, Lisveth; Ramos Fernández, Lía
Due to the outbreak of the novel coronavirus disease there is a need for public water supply of the highest quality. Adequate levels of chlorine allow immediate elimination of harmful bacteria and viruses and provide a protective residual throughout the drinking water distribution network (DWDN). Therefore, a residual chlorine decay model was developed to predict chlorine levels in a real drinking water distribution network. The model allowed determining human exposure to drinking water with a deficit of residual chlorine, considering that it is currently necessary for the population to have clean water to combat coronavirus Covid 19. The chlorine bulk decay rates (kb) and the reaction constant of chlorine with the pipe wall (kw) were experimentally determined. Average kb and kw values of 3.7 d− 1 and 0.066m d− 1 were obtained, respectively. The values of kb and kw were used in EPANET to simulate the chlorine concentrations in a DWDN. The residual chlorine concentrations simulated by the properly calibrated and validated model were notably close to the actual concentrations measured at different points of the DWDN. The results showed that maintaining a chlorine concentration of 0.87 mg L− 1 in the distribution tank, the residual chlorine values in the nodes complied with the cuadorian standard (0.3 mg L− 1); meanwhile, about 45% of the nodes did not comply with what is recommended by the WHO as a mechanism to combat the current pandemic (0.5 mg L− 1). This study demonstrated that residual chlorine modeling is a valuable tool for monitoring water quality in the distribution network, allowing to control residual chlorine levels in this pandemic season.
Integration of high-rate filtration using waste-derived biochar as a potential sustainable technology for drinking water supply
(2023) Barros Bermeo, Monica Estefania; García Ávila, Fausto Fernando; Galarza Guaman, Andres Geovanny; Avilés Añazco, Alex Manuel
This research aimed to evaluate the efficiency of eucalyptus (E) and bamboo (B) residual biomass biochars as filter materials for drinking water treatment. The efficiencies of these two biochars in the rapid filtration process were evaluated using water (raw, flocculated and settled) at the rate of 120 m3/m2/d. Finding that bamboo biochar manufactured under a slow pyrolysis process "b" (Bb) had the best performance. Subsequently, Bb was evaluated with three different granulometries, and it was found that the effective size with the best performance was the finest (0.6–1.18 mm). Subsequently, this biochar was compared with conventional filter materials such as gravel, sand and anthracite, using different types of water (raw, flocculated and settled) and at different filtration rates (120 and 240 m3/m2/d), and it was found that the filter material with the best performance was precisely biochar, with average removal efficiencies of 64.37% turbidity and 45.08% colour for raw water; 93.9% turbidity and 90.75% colour for flocculated water, and 80.79% turbidity and 69.03% colour for settled water. The efficiency using simple beds of sand, biochar, anthracite and gravel at the rate of 180 m3/m2/d was 75.9% copper, 90.72% aluminium, 95.7% iron, 10.9% nitrates, 94.3% total coliforms and 88.9% fecal coliforms. The efficiencies achieved by biochar were higher compared to those of conventional filter materials. It was also found that biochar contributes to improving the performance of sand and anthracite in mixed beds. Additionally, it was possible to demonstrate that the volume of washing water required for the biochar is lower compared to the other filter beds. Finally, it is recommended to carry out more tests for the purification of water with biochars from rural areas affected by the mining and oil exploitation, as well as the purification of seawater with biochars from coastal areas with residues from dry forests and organic residues from municipalities. Graphical abstract: [Figure not available: see fulltext.]
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.
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.
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.
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.