Ingeniería Ambiental-Pregrado

Permanent URI for this collectionhttps://dspace-test.ucuenca.edu.ec/handle/123456789/284

Browse

Now showing 1 - 20 of 297

Análisis de la precipitación mediante la evaluación de índices climáticos extremos en el territorio ecuatoriano continental
(Universidad de Cuenca, 2022-05-26) Saritama Chérrez, Hugo Giordano; Valdivieso García, Katy Viviana; Avilés Añazco, Alex Manuel; Contreras Silva, Juan José
Today, climate change is one of the main environmental threats affecting the world. The consequences of constant meteorological variations can become catastrophic, an example the increase in extreme weather events such as droughts and floods, due to the variability of precipitation; hence the importance of studying climate trends. The present study analyzed the extreme climate events of precipitation at the spatio-temporal level in continental Ecuador for the historical period 1980-2015 and future 2016-2070 under the projections RCP4.5 and RCP8.5, based on the evaluation of 11 extreme climate indices proposed by the Expert Group on Climate Change Detection and Indices (ETCCDI). For this purpose, daily precipitation data from 41 stations subject to rigorous quality control intended for a training set to improve the spatio-temporal representation using the RF-MEP methodology that combines ground data and satellite images by means of random forests. On the other hand, for the use of RCP4.5 and RCP8.5 a statistical downscaling was performed using the quantile delta mapping (QMD) method. Consequently, extreme precipitation indices were calculated using the RClimdex package, a trend analysis was performed using the Mann Kendall test and Sen's method was applied to determine their magnitude. The results and analysis of precipitation indices showed the occurrence of historical extreme events related to the El Niño phenomenon, as well as an increase in precipitation trends in future scenarios, especially in RCP8.5. This research provides a general idea of the historical changes in precipitation through the indexes, as well as the possible scenarios of future changes in the short, medium and long term, so that climate hazard analysis studies can be carried out; making it possible for decision-makers and citizens to apply measures for the control, regulation and protection of water resources.
Análisis de estacionalidad espacio-temporal de la nubosidad sobre el parque nacional Cajas y la zona urbana de Cuenca con productos satelitales (sentinel- 2) y estimación de la radiación solar mediante ecuaciones basadas en el porcentaje de nubosidad
(Universidad de Cuenca. Facultad de Ciencias Químicas, 2026-02-22) Rojas Yanzaguano, Marco Patricio; Carrillo Rojas, Galo José
This research addressed the spatio-temporal variability of cloud cover in El Cajas National Park and the urban area of Cuenca, focusing on its impact on available solar radiation. The objective was to analyze this seasonality using Sentinel-2 satellite products to evaluate cloud cover and estimate solar radiation through equations based on cloud percentage, validating the results against pyranometer measurements from local stations. The methodology was based on the collection and processing of high-resolution satellite imagery, cloud cover classification, and the application of empirical and statistical models to estimate solar radiation, complemented by validation with observational data. The findings are consistent with the international, regional, and local literature reviewed, which shows that cloudiness is a determining factor in radiation variability; these analyses achieved correlation coefficients above 0.85 and acceptable error margins across various contexts, despite limitations in páramo ecosystems. An inverse relationship between cloud cover and radiation was observed, confirming the potential utility of satellite data in order to compensate for the scarcity of meteorological stations. In conclusion, the study established that integrating Sentinel-2 imagery with ground measurements improves solar radiation estimation, contributing to the sustainable management of energy and water resources, urban planning, and climate change adaptation in the Andean region.
Determinación experimental del coeficiente de rugosidad Manning en el río Tomebamba; tramo Av. de los Cerezos hasta la Av. Unidad Nacional y Av. 3 de Noviembre
(Universidad de Cuenca. Facultad de Ciencias Químicas, 2026-02-21) Londa Cañar, Pablo Fernando; Avilés Añazco, Alex Manuel; Zhiña Villa, Darío Xavier
Water resource management faces challenges arising from urban development and climate variability, which positions hydraulic modeling as a key tool, with Manning’s roughness coefficient (n) being a fundamental parameter in natural rivers. The present study determined this coefficient for the Tomebamba River, in the reach between Los Cerezos Street and the intersection of Unidad Nacional Avenue and 3 de Noviembre Avenue, in Cuenca, through the development of a two-dimensional hydraulic model in HEC-RAS 6.6, based on a 3 × 3 m Digital Elevation Model, discharge records, and in situ water level measurements from 16 events. The calibration, conducted by comparing observed and simulated water levels, showed that low roughness values (n = 0.030 and n = 0.040) underestimate water levels, whereas n = 0.064 overestimates them, with the best fit obtained for n = 0.062, which yielded a mean absolute error of 0.015 m, an R² of 0.98, and a Nash–Sutcliffe efficiency of 0.95; validation with 11 events showed satisfactory performance (R² = 0.74; NSE = 0.75), results consistent with previous studies in inter-Andean mountain rivers and constituting a technical contribution to hydraulic modeling, risk management, and urban planning in the city of Cuenca, recommending the inclusion of a greater number of flood events in future research.
Eficiencia de coagulantes orgánico, inorgánico y mixto, en la recuperación ex situ de la calidad del agua de la laguna San Martín del cantón Girón (Ecuador)
(Universidad de Cuenca. Facultad de Ciencias Químicas, 2026-02-19) Bustamante Guzmán, Diego Andrés; Vallejo Siguenza, Israel Patricio; Jara Torres, Pablo Patricio
This study was conducted in San Martin Lagoon, canton Girón (Ecuador), with the objective of evaluating the efficiency of organic, inorganic, and mixed coagulants applied ex situ, analyzing their effect on turbidity, color, dissolved oxygen, pH, biochemical oxygen demand (BOD), electrical conductivity, nitrates, and phosphates. The methodology included an initial physicochemical characterization through sampling at eight points and, subsequently, the application of the jar test with four formulations: organic (banana peel powder), inorganic (aluminum sulfate), and two mixtures (75 % organic - 25 % inorganic and 25 % organic - 75 % inorganic), evaluated at doses of 33.33 mg/L and 250.5 mg/L. Removal efficiency was determined through analysis of variance, complemented by a cost analysis per cubic meter treated. The technical-economic analysis determined that treatment feasibility depends on the balance between performance and cost. The organic coagulant at low dose was the most economical (0.0262 USD/m3) but showed technical efficiencies with negative results in color, nitrates, and BOD. In contrast, the inorganic coagulant at 33.33 mg/L presented the best cost-benefit balance (0.0443 USD/m3), achieving phosphate removals exceeding 97 % and BOD reduction of 80.17 %, without significantly altering pH or conductivity and avoiding the high costs of elevated doses. Finally, it is concluded that the lagoon presents marked seasonal degradation; in this context, the use of inorganic coagulants at low doses or mixed formulations optimizes treatment efficiency and improves water quality.
Evaluación de la eficiencia de remoción en ibuprofeno en aguas residuales sintéticas, mediante el uso de vermifiltros
(Universidad de Cuenca. Facultad de Ciencias Químicas, 2026-02-02) Andrade Pástor, Mateo Vicente; Pérez Corte, Sergio Ariel ; Guanuchi Quito, Alexandra Elizabeth
Ibuprofen (IBU) is a widely consumed pharmaceutical used for pain relief; however, when it enters the environment through various pathways, it becomes part of the group of emerging contaminants (ECs). These compounds pose a potential risk to aquatic ecosystems, even at low concentrations. Conventional wastewater treatment systems show low efficiency in the removal of IBU, which has driven research into sustainable biological alternatives such as activated sludge processes, biofilters, and vermifiltration. In this context, the present study evaluated the efficiency of vermifiltration which combines the biological activity of Eisenia fetida earthworms with the adsorption capacity of filtering materials such as coconut fiber, sand, and gravel used as support and aeration media—for the removal of ibuprofen from synthetic wastewater. The experiments were conducted under controlled laboratory conditions through the design and implementation of two systems, consisting of a control filter and a vermifilter. Two IBU concentrations were applied to the systems: a maximum of 12,28 ppm and a second concentration of 6,14 ppm. Samples were subjected to solid-phase extraction using C18 cartridges and analyzed by high-performance liquid chromatography (HPLC). Statistical analysis using two-way ANOVA showed that the presence of earthworms did not produce statistically significant differences in ibuprofen removal efficiency. Nevertheless, the median removal efficiency of the vermifilters was 96.07%, which was higher than the 85.30% median removal efficiency obtained for the control filter.
Eliminación del nitrógeno amoniacal de los lixiviados de Pichacay mediante el proceso Anammox
(Universidad de Cuenca. Facultad de Ciencias Químicas, 2026-02-19) Huanga Huanga, Erika Valeria; Méndez Valladares, Verónica Magdalena; Cisneros Ramos, Juan Fernando
The increase in waste production has led to the need to find new technologies for its management. Landfills are one of the least favorable ways to manage waste, as they produce potentially toxic leachates that, if not properly managed, can have negative impacts on ecosystems. In the city of Cuenca, leachate is treated in stabilization ponds using conventional technologies associated with maintenance and operational risks. In this study, a sample of leachate from the Pichacay landfill was treated using the Anammox process to remove nitrogen compounds. Six tests were carried out over 230 days, plus a final test in which disinfected leachate was introduced into the adapted substrate. The results indicated that, in E6, the system achieved ammonium removals of over 80 %. Meanwhile, the final test recorded efficiencies of 40,63 % in NH4+ removal, 46,67 % in NO2- consumption, and 11,43 % in NO3- formation. The resilience of the substrate to higher concentrations and the potential presence of compounds that inhibit the process was verified. Given the increase in nitrite concentrations in some tests due to operational and biological limitations of the substrate, symbiotic action between Nitrosomonas, whose metabolism involves partial nitrification, and competition for substrate with Nitrobacter bacteria, which carry out the nitration process, is suggested. The results indicate the possible activity of partial nitrification and simultaneous Anammox.
Modelo de simulación dinámica para evaluar el abastecimiento de agua potable en una red de distribución en la ciudad de Azogues
(Universidad de Cuenca. Facultad de Ciencias Químicas, 2026-02-19) Gallegos Morocho, David Agustín; Lituma Tacuri, Henry Santiago; García Ávila, Fausto Fernando
The drinking water supply system of Bayas parish presents deficiencies associated with population growth, aging infrastructure, losses in the distribution network, and climate variability factors that compromise the continuity and sustainability of the service. The objective of this study was to develop a dynamic simulation model to evaluate system performance and support water planning for the Bayas Drinking Water Board. The research adopted a quantitative and systemic approach using system dynamics methodology. Critical variables were identified and classified into levels, flows, and auxiliary variables, organized within the components of supply, demand, infrastructure, management, and environmental factors. A causal diagram was developed to represent cause–effect relationships and feedback loops. Subsequently, a stock-and-flow (Forrester) model was constructed, mathematically formulating the water balance and population dynamics, and implemented in VENSIM using historical data and technical parameters provided by the Board. Simulations projected to 2050 reveal a growing risk of deficit, mainly driven by population increase and leakage losses. Storage capacity and treatment efficiency act as regulatory mechanisms for supply stability. The system shows high sensitivity to variations in water availability, increasing its vulnerability under scenarios of reduced precipitation. The model identified critical intervention points, particularly in loss reduction and infrastructure expansion planning, consolidating dynamic simulation as a strategic tool for decisión making and long-term service sustainability.
Evaluación de dosis óptimas de mezclas de aceites esenciales en la desinfección de aguas residuales tratadas en un vermifiltro
(Universidad de Cuenca. Facultad de Ciencias Químicas, 2026-02-19) Montoya Sánchez, Esteban Ariel; Peñaloza Zhispon, Ulises Fernando; Guanuchi Quito, Alexandra Elizabeth
In the present investigation, essential oil mixtures were evaluated for the disinfection of wastewater treated in a vermifilter, focusing on the elimination of fecal coliforms and amoebae. Through literature review, thyme (Thymus vulgaris) and tea tree (Melaleuca alternifolia) essential oils were selected, with previous studies reporting their potential antimicrobial activity. A mixture design was applied to evaluate the effectiveness of the treatments. The analysis of results indicates that the most effective treatments for eliminating fecal coliforms were thyme oil and the mixture formulated with thyme oil 75% - tea tree oil 25%. For the elimination of amoebae, thyme and tea tree essential oils were most effective. The treatments were more effective in disinfection by adding 7.5 mL for 120 minutes. However, only the mixture of thyme oil 75% - tea tree oil 25% meets the parameter required by the Ecuadorian Water Quality Standards for irrigation, with a value of 130 NMP/100 mL in fecal coliforms. None of the treatments meet the standard parameter for elimination of amoebae.
Análisis de la concentración de microplásticos en el aire de la Ciudad de Cuenca en una gradiente altitudinal
(Universidad de Cuenca. Facultad de Ciencias Químicas, 2026-02-02) Guevara Segarra, Paulina Soledad; Naranjo Asencio, Sofia Fernanda; Mejía Coronel, Julio Danilo
Microplastics are widely distributed in natural environments, food, and the human body, representing a growing environmental and public health concern. In this context, the present study aimed to analyze the deposition rate of microplastics in the air of the city of Cuenca according to its altitudinal gradient. The research was descriptive in nature, with a non- experimental, cross-sectional, and correlational design, and a quantitative approach. Particle detection was carried out through the filtration of air samples, followed by visual identification under a stereomicroscope. Two independent replicates were collected at each of the 20 sampling points selected by convenience. The results show average microplastic deposition flux values (particles/m2·day) in 17 of the 20 evaluated sampling points (85%), demonstrating their presence at different altitudes throughout the city. No particles were recorded in the remaining 15% of the sampling points. Additionally, some locations with high deposition values also showed elevated levels of settleable particulate matter. Spearman’s correlation coefficient (ρ = 0.21) indicates a weak positive correlation between altitude and deposition rate, suggesting a slight increasing trend in microplastics with higher elevation. However, the low magnitude of the coefficient indicates that altitude is not the only factor influencing their distribution. In conclusion, the widespread presence of microplastics in the air of Cuenca is confirmed, constituting an environmental problem with potential implications for public health.
Determinación del potencial de generación de biogás a partir de residuos orgánicos de las parroquias Nazón y Sageo (Biblián)
(Universidad de Cuenca. Facultad de Ciencias Químicas, 2026-02-19) Segura Paima, Melanie Kris; Sumba Sumba, Lourdes Elizabeth; Cisneros Ramos, Juan Fernando
The objective of this study was to determine the biogas generation potential from organic waste in the parishes of Nazón and Sageo (Biblián). The problem addressed is related to the deficient management of Municipal Solid Waste (MSW), considering that more than 50 % of the waste generated is organic matter that does not receive adequate treatment, contributing to the emission of Greenhouse Gases (GHG), primarily methane and carbon dioxide. The research began with the collection and analysis of information on waste generation in the Biblián canton during the period 2017–2024, as well as a projection to the year 2035. Subsequently, household waste was sampled and characterized, evaluating parameters such as composition, moisture, volatile solids, and C/N ratio. A Biochemical Methane Potential (BMP) assay was carried out under controlled conditions, with 12 assays per parish. The results showed a potential of 16.386 NmL/kg for Nazón and 13.415,6 NmL/kg for Sageo. Based on these values, an average energy generation of 609,8 kWh/year was estimated for Nazón and 289,9 kWh/year for Sageo, considering a combined heat and power (CHP) system with an efficiency of 35 %. These results represent a reference scenario for energy utilization. Finally, it was determined that factors such as waste composition, moisture, pH, pressure, volatile solids, and C/N ratio directly influence the efficiency of the anaerobic process, allowing for recommendations aimed at the valorization of organic waste and the strengthening of the circular economy.
Análisis del desempeño de un sistema de vermifiltración en la remoción de iones de cobre y cromo de aguas residuales sintéticas a escala piloto
(Universidad de Cuenca. Facultad de Ciencias Químicas, 2026-02-18) Crespo Mora, Niurka Galilea; Urgilez Coronel, Raniero Oswaldo; Guanuchi Quito, Alexandra Elizabeth
The presence of heavy metals in wastewater represents an environmental concern due to their toxicity, persistence, and bioaccumulation capacity, generating adverse impacts on ecosystems and human health. Among these contaminants, copper (Cu2+) and hexavalent chromium (Cr(VI)) frequently reach water bodies through domestic and industrial discharges that do not always receive adequate treatment. In this context, vermifiltration emerges as a sustainable treatment alternative based on combined physical and biological processes involving earthworms of the species Eisenia fetida.This study evaluated the performance of a pilot-scale vermifiltration system for the removal of Cu2+ and Cr(VI) from synthetic wastewater, comparing it with a control filter without earthworms. Four experimental filtration units were operated under identical hydraulic conditions in batch mode, considering effective contact time as a parameter for system characterization. Influent and effluent metal concentrations, along with complementary physicochemical parameters, were monitored throughout the experimental period.Results showed reductions of both metals in the two filtration systems; however, no statistically significant differences were found between vermifilter and control filter removal efficiencies. Likewise, small variations in effective contact time did not significantly influence treatment performance. Overall, both systems exhibited comparable behavior, indicating that vermifiltration constitutes a viable and low-cost alternative for treating synthetic wastewater contaminated with heavy metals.
Monitoreo de la calidad del aire ambiente en los accesos a cuatros escuelas del casco urbano del cantón Cuenca referente a intervenciones de urbanismo táctico
(Universidad de Cuenca, 2023-07-19) Abad Merchán, Pamela Nicole; Ramírez Ramírez, Darleny Samanta; Astudillo Alemán, Ana Lucía
This work presents the evaluation of ambient air quality in four educational institutions: "Nicolas Sojos," "Abelardo Tamariz," "Panamá" and "Luis Cordero" in the canton of Cuenca in the context of tactical urbanism interventions. For this purpose, the concentrations of sedimentable particles, sound pressure levels, and concentrations of metals such as Al, Mn, Zn, Fe, Co, and Cr in transplanted bryophytes of the genus Bryum. The monitoring of sedimentable particles was carried out in three stages, exceeding the standard (> 0,50 mg/cm2*30 days) in the Luis Cordero and Abelardo Tamariz schools in stage 1, and the Panama, Luis Cordero, and Abelardo Tamariz schools in stage 2. In stage 3, only the Abelardo Tamariz school exceeded the national standard (> 1,00 mg/cm2*30 days). The sound pressure levels recorded varied between 56 - 86 dB(A) and were higher than national, and local regulations. After the interventions, there were no significant differences with the levels initially recorded. Regarding the concentrations of metals in the mosses, the highest concentration was for Al (1 475,50 mg/kg) and the lowest for Co (0,15 mg/kg). In addition, the Abelardo Tamariz school had the highest concentration of metals, and Zn was most related to road traffic (r = 0,98). The conclusions state that the schools present contamination by settleable material and exceeded sound pressure levels, and the results did not vary significantly by the tactical urban planning interventions.
Evaluación de la eficiencia de filtros de carbón activo a escala de laboratorio para la retención de microplásticos de aguas residuales
(Universidad de Cuenca, 2025-09-18) Muñoz Torres, Romel Gerardo; Quizhpilema Marin, Samantha Katherine; Guanuchi Quito, Alexandra Elizabeth
Microplastic pollution in water bodies poses a growing threat to both environmental and human health. This study evaluated the efficiency of laboratory-scale filters using activated carbon (AC) for the retention of microplastics in wastewater from the Ucubamba Wastewater Treatment Plant (WWTP) in Cuenca, Ecuador. Three filter columns were designed with activated carbon bed heights of 20, 25, and 30 cm, each also composed of stratified layers of gravel and sand. The system operated under controlled conditions, including flow rate, hydraulic retention time, and sampling frequency. Samples obtained after membrane filtration, containing retained microplastics (MPs), were analyzed using rhodamine B staining, UV fluorescence, and optical microscopy, allowing for the quantification of initial concentrations ranging from 2.3 to 5.7 million MPs/L. After treatment, favorable microplastic removal percentages were achieved, with Filter 3 standing out for its 78.98% efficiency. This performance is attributed to optimal operational conditions: the greatest activated carbon bed height (30 cm) and extended contact time (2 hours). Subsequently, when comparing the efficiencies of the three types of activated carbon (vegetal, powdered, and granular) powdered activated carbon (PAC) exhibited the highest removal efficiency, reaching 80.08%. This result is associated with its finer structure, which enhances surface interaction and adsorption kinetics with microplastics.
Caracterización y cuantificación de microplásticos presentes en el río Machángara de la ciudad de Cuenca
(Universidad de Cuenca, 2025-09-04) Guambaña Palaguachi, Néstor Iván; Palma Portilla, Kevin David; Guanuchi Quito, Alexandra Elizabeth
Microplastic pollution poses a growing threat to aquatic ecosystems both nationally and globally. This study focused on the quantification and classification of microplastics in the Machángara River, one of the main water bodies in the city of Cuenca, Ecuador. This river is especially important because its upper section provides water for human consumption, while its lower section is used for agricultural, industrial, and other anthropogenic purposes. Five strategic sampling points were established along the river: 1) Chanlud Dam, 2) Rural Area Start, 3) Industrial Park Start, 4) Industrial Park End, 5) Confluence with the Tomebamba River. The sample collection followed the Ecuadorian Technical Standard NTE INEN 2176:2013, using composite sampling techniques to ensure representativeness. The samples were then processed and analyzed in the laboratory of the Center for Environmental Studies (CEA) using a stereomicroscope to classify microplastics by shape (fragments, fibers, spheres, films, and sponges), size, and concentration. Results showed a high presence of microplastics, with a maximum concentration of 15,754 particles per liter (part/L), and significant variations across sampling points and weeks, with increases in urban and industrial areas. Morphologically, the most common types of microplastics were fragments, sponges, and films, ranging in size from 0.24 µm to 4,410 µm. These findings confirm the presence of microplastics in the Machángara River, indicating potential risks for both environmental and human health. Therefore, it is essential to implement appropriate management strategies and promote awareness about the responsible use and disposal of plastics.
Optimización de la desinfección mediante el uso de malla y viruta de cobre en los procesos de filtración y post-filtración en la planta de potabilización de la Junta de Agua Potable “Bayas”
(Universidad de Cuenca, 2025-09-12) Gutiérrez Cedillo, Sofía; Pérez Sucuzhañay, Rosa Magaly; García Ávila, Fausto Fernando
The quality of drinking water is a critical challenge, especially in rural areas where high levels of pathogenic microorganisms pose a significant risk to public health. The consumption of contaminated water can cause serious diseases, highlighting the urgent need to optimize disinfection processes to ensure access to safe water. The objective of this study was to optimize the disinfection of drinking water through the use of copper mesh and shavings in filtration and post-filtration processes at the “Bayas” Drinking Water Board treatment plant. The aim was to improve the removal of pathogenic microorganisms and ensure water quality. To evaluate the effectiveness of copper, an experimental design was implemented comparing conventional filtration with the copper contact system, both before and after filtration. The most probable number (MPN) technique was used to estimate the quantity of coliforms in the collected samples. In addition, physicochemical analyses were carried out, considering parameters such as pH, turbidity, and nitrates, which are essential for assessing water quality. The results showed that the use of copper mesh and shavings significantly reduced total and fecal coliforms compared to the conventional system. Furthermore, copper contact in post- filtration proved more effective in disinfection, contributing notably to the microbiological safety of the water. In conclusion, copper-based technologies represent a viable alternative to improve drinking water disinfection in rural communities, reducing health risks and promoting healthier and more sustainable environments.
Efecto del sulfato de cobre como germicida en aguas residuales domésticas tratadas en humedales artificiales
(Universidad de Cuenca, 2025-09-05) Granda Loayza, Daniela Mishel; Salazar Armijos, María José; García Ávila, Fausto Fernando
In many rural areas, domestic wastewater treatment remains a pending task due to structural and social constraints. This situation represents a risk to both public health and the environment due to the presence of pathogenic microorganisms in the effluents. In this context, this research evaluated the use of copper sulfate as a germicidal agent in a real-life treatment system that includes a septic tank, a coagulation process, and a subsurface flow constructed wetland. In the laboratory, jar tests were conducted with different copper sulfate concentrations (1–5%) and doses between 150 and 400 mg/L to determine the most effective. The optimal dose (250 mg/L at 3%) was subsequently applied to the full-scale system. The results showed high removal efficiencies for turbidity (90%), BOD (93%), COD (95%), phosphates and nitrates (97%), and fecal coliforms (>95%). However, an increase in ammoniacal nitrogen was detected (up to 34.78%), possibly due to the inhibition of nitrifying bacteria. Furthermore, the effectiveness of copper sulfate was compared with chlorine and aluminum sulfate. Chlorine was the most effective (99.9% coliform removal), followed by copper sulfate (80.4%) and aluminum sulfate (47.6%). Overall, the results support the use of copper sulfate as a viable alternative to improve water quality in rural communities where access to conventional technologies is limited.
Determinación de la biomangificación de oligoelementos tóxicos en leche cruda; por biotransferencia desde agua y pasto en una hacienda modelo de la parroquia Tarqui, Cuenca, Ecuador; y su posible riesgo toxicológico
(Universidad de Cuenca, 2025-08-21) Hurtado Ordoñez, Pedro José; Uguña Encalada, Gabriela Cristina; Uguña Rosas, María Fernanda
Environmental contamination by heavy metals constitutes a relevant threat to food safety and public health. This research evaluated the concentrations of arsenic (As), cadmium (Cd), and lead (Pb) in raw bovine milk produced at a model farm in the parish of Tarqui, Cuenca, Ecuador, as well as the biotransference of these metals from water and pasture, and the toxicological risks derived from their consumption. Samples of milk, water, and pasture were collected and analyzed using inductively coupled plasma mass spectrometry (ICP-MS), and the biotransference factors (BTF) and risk indices were calculated: Hazard Quotient (HQ), Hazard Index (HI), and Incremental Lifetime Cancer Risk (ILCR). The results showed elevated concentrations of lead (1.54 mg/kg), cadmium (0.058 mg/kg), and arsenic (0.2361 mg/kg) in milk, exceeding the limits established by Ecuadorian and international standards. Although the BTF values were low (below 1), indicating limited biomagnification from environmental sources, the final concentrations in milk reflected significant contamination in water and pasture. Toxicological analysis revealed HQ values greater than 1 in individuals under 55 years of age and HI values above 1 in all age groups, indicating non-carcinogenic risk. Likewise, ILCR values for arsenic (9.53 × 10−3) and cadmium (9.84 × 10−3) exceeded the acceptable range established by the EPA (10−6–10−4), evidencing a considerable carcinogenic risk. In conclusion, these findings reflect a serious food safety and public health issue, underscoring the need for environmental and sanitary control measures in rural milk-producing areas.
Eficiencia de los vermifiltros como tratamiento primario para la remoción de microplásticos en aguas residuales urbanas del cantón Cuenca
(Universidad de Cuenca, 2025-09-01) Albarracin Zeas, Mateo Andres; Sánchez Cabrera, Camila Fabiola; Guanuchi Quito, Alexandra Elizabeth
The main objective of this study is to evaluate the efficiency of a vermifiltration system for the reduction of microplastics (MPs) in urban wastewater, considering the Ucubamba Wastewater Treatment Plant (WWTP) in the Cuenca canton as the study area. For this purpose, a pilot vermifiltration system implementing the Eisenia fetida species was used, and its performance was compared with a biofilter without worms. Physicochemical parameters of the water were characterized before and after vermifiltration treatment, and microplastics were also identified and quantified by oxidative digestion, vacuum filtration, and microscopic observation. Regarding microplastics, particles belonging to polymers such as polyvinylpyrrolidone (PVP), polyamide, thermoplastic polyester (#7), and chlorinated polyethylene were detected with Fourier Transform Infrared Spectroscopy (FTIR) equipment. Therefore, it is evident that the vermifilter achieved a significantly higher removal efficiency than the biofilter, reaching percentages greater than 60% in the reduction of microplastics. Furthermore, in the analysis of the physical and chemical parameters, improvements were observed in the Chemical Oxygen Demand (COD) parameters, reaching a percentage reduction of up to 72% and in total suspended solids with a reduction of 68%. In the statistical analysis of the physical and chemical parameters, significant differences were evident between the values of the influent and effluent, which supports the effectiveness of the vermifiltration system. Based on the results obtained and the statistical analyses developed, vermifiltration systems are considered to improve the quality of the treated water, thus contributing to minimizing the environmental impacts associated with effluent discharge.
Estrategias para minimizar la producción de residuos peligrosos y maximizar la recuperación de materiales: un análisis del flujo de materiales en Continental Tire Andina S.A.
(Universidad de Cuenca, 2025-09-02) Espinoza Murillo, Andrea Nayeli; Vásquez Ochoa, Kenny Leonardo; Cisneros Ramos, Juan Fernando
The objective of this study is to minimize the production of hazardous waste and maximize the recovery of materials in the tire industry, Continental Tire Andina S.A., through a material flow analysis of the productive and non-productive processes that generate hazardous waste. A qualitative material flow analysis of the entire plant process and a quantitative material flow analysis was carried out over a period of one month, with the areas that produce the greatest amount of hazardous waste, including the productive process of mixing and relating it to the non-productive processes: laboratory, cleaning, maintenance and operation, using the STAN software.The areas and causes of hazardous waste generation in the plant were identified and 8 management strategies grouped into three scenarios were established: operational optimization, technical innovation and control of priority waste. Each of the scenarios was evaluated technically, environmentally and economically, with the best alternative being scenario 3, which includes management improvement strategies, process changes and material substitution, resulting in a reduction of 14 407,61 kg of hazardous waste and generating savings of US$3 760,3 per month in its treatment. This scenario stands out for the positive environmental impact it generates and the balance between technical and economic aspects.
Análisis de las relaciones entre sequía meteorológica e hidrológica presente en las estaciones de Chanlud, Labrado y Saucay en la subcuenca del río Machángara
(Universidad de Cuenca, 2022-07-26) Campoverde Pesántez, Viviana Lucía; Avilés Añazco, Alex Manuel
Climate changes at a global level have been modifying regional climate patterns, which has had as a major consequence over the presence of extreme hydrological events, as it is the case of drought. Droughts have directly affected the provision functions of the ecosystem services provided by the watersheds throughout each region. The present investigation analyzed the relationship between hydrological and meteorological droughts for the meteorological stations of Chanlud, Labrado and Saucay in the sub-basin of the Machángara River, located in the city of Cuenca - Ecuador, between the years 2000-2019. For its development, linear and nonlinear models were considered to relate the standardized precipitation index (SPI) and the standardized flow index (SSI), as well as the use of evaluation metrics for model validation. In addition, through the Run Theory, droughts were characterized and categorized by their duration and magnitude. Through models and six validation criteria, it was possible to identify that there is a direct relationship in both the duration and magnitude of these two types of droughts. However, the structures of the models were different, without this interfering with the efficiency of their results. This is how it was possible to show that the presence of large reservoirs becomes a great help for the management of water resources, minimizing the vulnerability of the population to extreme weather events and also to guarantee a reliable water supply

Browse

Recent Submissions