Repositorio Institucional Universidad de Cuenca
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Fog in the Andean Páramo: measurements, dynamics, and its influence on soil hydrology and evapotranspiration processes
(Universidad de Cuenca, 2022-09-15) Berrones Guapulema, Gina Marcela; Célleri Alvear, Rolando Enrique
The páramo ecosystem is characterized by a very moist climate and the continuous presence of fog and low-intensity rainfall. The most important páramo feature is the high water regulation capacity which in part might be related to the high frequency of fog and low-intensity rainfall (drizzle).
Therefore, it is essential to understand the hydrological processes that are linked to the ecology of the páramo. This study aimed the following three objectives: (1) to assess fog water estimates derived from three different types of fog gauges, and from them to understand its temporal dynamics and the importance of fog to annual rainfall; (2) to quantify the contribution of fog water deposition to soil moisture; and (3) to analyze the impact of fog on evapotranspiration rates, under different weather conditions (clear, foggy and rainy). Findings of this study show that fog occurs at very low intensities (0.2 mm h-1) reporting events of short term (<3 hours) at wind velocities below 4 m s-1. Most of the time fog appears combined with other type of precipitation (i.e. drizzle, light rain or rain) with fog tending to be more intense in the early morning, and at night. On average, daily fog amounts 1.37 mm. Overall, fog and drizzle are the major water sources to páramo vegetation, especially during late night-time and early mornings, when evaporation is low. The fog water deposition shows that only 4.5% of fog reaches the soil, contributing to soil moisture changes rather low (0.1-0.2 mm), whilst the combination of fog with low-intensity rainfall generate a higher contribution on soil moisture (as high as 4.3 mm). These events are potentially important for both soil moisture and stream flow, because of their long duration and high total amount per-event. Daily evapotranspiration rates are reduced by 43% due to the presence of mixed conditions (fog + lowintensity rainfall) compared with clear conditions (no fog and no rainfall). The net radiation is reduced by 9.2% during foggy conditions (only fog) mainly because its early morning hours occurrence is higher, and when solar radiation peaks fog occurrence is lower. While, during mixed conditions the net radiation is reduced by 33%. At the same time as less humid periods were reported, evapotranspiration was also low; suggesting that fog and drizzle presence can inhibit transpiration, limit water loss by evaporation and also could alleviate water stress.
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.
Evaluación ergonómica integral del área de envasado de una empresa de producción de minerales no metálicos, considerando los riesgos asociados a los movimientos repetitivos, la manipulación manual de cargas y posturas forzadas
(Universidad de Cuenca. Facultad de Ciencias Químicas, 2026-02-20) Fárez Plasencia, Jhon Walter; Espinoza Hernández, Paulina Rebeca
The growing non-metallic mineral processing industry dedicated to the production of cat litter faces significant occupational health challenges due to the physical demands inherent in its production processes. This study assessed ergonomic risks in the packaging area with the objective of identifying biomechanical factors associated with musculoskeletal disorders and proposing an improvement plan aligned with ISO 45001:2018. A cross-sectional descriptive design was conducted involving a population of 20 workers, of whom 18 were evaluated. Validated assessment tools were applied for risk identification and analysis: the Revised NIOSH Lifting Equation for manual material handling; the OCRA Checklist for repetitive upper- limb movements; the REBA method for forced postures; and the MultiGEI model, considering job rotation conditions. The prevalence of musculoskeletal symptoms was determined using the Standardized Nordic Questionnaire. Results revealed a very high risk associated with manual handling of loads up to 30 kg, with a Lifting Index (LI) of 2.01 and a global MultiGEI index of 23.6, classified as critical. Additionally, the automated workstation presented a considerable risk due to repetitiveness (OCRA = 16.5). Low back pain was reported by 94.4% of workers and shoulder pain by 77.8%. Task rotation was found to be insufficient, and the implementation of mechanical aids, ergonomic workstation redesign, and structured active breaks is recommended to mitigate risk and strengthen preventive management within the occupational health and safety system.
Prevalencia de sobrepeso y obesidad en perros de la ciudad de Cuenca, Ecuador
(Universidad de Cuenca. Facultad de Ciencias Agropecuarias, 2026-02-11) Flor Aguirre, Joel Sebastián; Picón Saavedra, Marco Antonio
Obesity represents a growing health crisis that links human health with that of companion animals, affecting nearly 55% of the canine and feline population. This condition can shorten a dog's life expectancy by up to 30% by triggering serious diseases such as diabetes, hypertension, orthopedic problems, and cancer. There are also risk factors such as breed, age, and sex. The objective of this study is to estimate the prevalence and analyze the possible risk factors associated with overweight and obesity in dogs in the city of Cuenca. The evaluation was based on the determination of the Body Condition Score. It was obtained by applying the WSAVA scale from 1 to 9. The statistical analysis was performed in IBM SPSS, classifying body condition in individuals without overweight and obesity (BCS ≤ 5) and those with these conditions (BCS ≥ 6). Prevalence was determined using descriptive statistics, and bivariate associations were evaluated using the Chi-square and Mann-Whitney U tests (after the Shapiro-Wilk test). The magnitude of association was determined using OR with a p-value < 0.05. The results obtained show a combined prevalence of overweight and obesity of 39.15% (32.86% overweight and 6.29% obese). The most decisive risk factor is age (62.0%), with race and reproductive status also comprising important risk factors; however, gender and physical activity were not shown to have an effect on the individual's nutritional status.
Evaluación de los cambios fisicoquímicos por deterioro del lactosuero crudo, dulce y ácido de quesería
(Universidad de Cuenca. Facultad de Ciencias Químicas, 2026-02-20) Muñoz Ortega, Emily Alexandra; Sumba Contreras, Layla Elizabeth; Ortiz Ulloa, Silvia Johana
Whey, or cheese whey, is an agro-industrial byproduct generated in large volumes during cheese production, with an estimated yield of nine liters of whey per kilogram of cheese. Despite its high nutritional value, it represents a significant environmental problem due to its high organic load. When discharged untreated into water bodies, it reduces dissolved oxygen levels and negatively affects plants, fish, and soil. In Ecuador, economic and regulatory limitations make it difficult for small producers to implement proper treatment and utilization processes, encouraging informal disposal. Furthermore, the lack of local data on its stability limits its potential applications. In this thesis project, the physicochemical parameters of sweet whey (SW) and acid whey (AW) were evaluated over 15 days under different storage conditions. Both types of whey were produced under laboratory-controlled conditions and stored in three ways: non-sterilized at room temperature (20 °C), non-sterilized and refrigerated (4 °C), and sterilized and refrigerated. The parameters analyzed included pH, titratable acidity, density, total solids, proteins, free amino acids, phosphorus, lactose, fat, ash, and moisture, measured on days 0, 2, 4, 10, 12, and 15. Results showed that room temperature accelerated deterioration, especially in SW, where pH decreased from 6.53 to 3.63 and titratable acidity increased from 9.85 to 87.0 °D. Refrigeration, and particularly sterilization combined with refrigeration, improved stability. In AW, variations were more moderate. These findings provide a technical basis for appropriate preservation and revalorization strategies.
