Browsing by Author "Mejía Coronel, Julio Danilo"

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Análisis de comparación de datos de contaminantes atmosféricos: CO, SO2, NO2, O3, CH2O entre Sentinel 5P y productos satelitales de OMI, MERRA-2 y AIRS en Ecuador
(Universidad de Cuenca, 2022-03-21) Padrón Crespo, César Israel; Cabrera Carrión, Carlos Xavier; Mejía Coronel, Julio Danilo
Air pollution is an environmental problem caused by gases emitted mainly by anthropogenic activities. The exposure of people to these pollutants mainly affects the respiratory and circulatory systems. Therefore, it is necessary to carry out studies on the conservation and concentration of pollutants to predict their behavior and take future actions. The present study statistically analyzes the quality of the data of atmospheric pollutants CO, SO2, NO2, O3 and CH2O measured by the Sentinel 5P satellite (TROPOMI Sensor) with respect to those equipped by the predecessor sensors (MERRA-2, OMI and AIRS). ) in the Republic of Ecuador from January 2019 to December 2020. The methodology performs a resampling or modification of the pixel size, matching the spatial resolution of the different ones for subsequent statistical analysis. It was obtained as a positive R2 coefficient value for O3 for AIRS and MERRA-2. For the other pollutants analyzed, determination coefficients were acquired that do not represent a correlation between the satellite products and Sentinel 5P. For a better analysis, data from ground stations located in the cities of Cuenca and Quito were used, thus determining a positive relationship for all the pollutants treated with the different satellite products, that is, the data obtained on the ground have an incidence with what is obtained in the satellite images. Subsequently, time series graphs were made to identify outliers, sudden changes, seasonal patterns, trends, etc. In addition, a resampling of a different pixel size was carried out to contrast it with the one carried out in principle, and it was determined that Sentinel 5P better explains the concentrations of the other satellite products.
Análisis de factores ambientales asociados a la presencia de metales pesados en aire alrededor de centros de educación inicial en la ciudad de Cuenca
(2020) Mejía Coronel, Julio Danilo; Parra Ullauri, Mayra Alejandra; Rodas Espinoza, Claudia; Andrade Tenesaca, Dolores Susana; Zegarra Peña, Ronny Rafael
Particulate matter (PM) air pollution, as a consequence of increasing traffic, is of high concern for public health in urban areas. The PM draws major attention, first because by its micrometric sizes can particles penetrate the lungs and hinder the gas exchange, and secondly due to its chemical composition including the presence of heavy metals, which can damage the biological systems. Despite its detrimental effects for the entire population, kids are more vulnerable because of its developing stage. It is known that PM concentrations can be influenced by street characteristics, meteorology, and the presence of surrounding vegetation, which constitute environmental factors related to the generation, dispersion, and deposition of PM. Due to the necessity of reducing population exposure to this type of pollution, the present study analyzed the correlation of environmental factors of generation, dispersion and deposition based on the available secondary information with the concentration of PM10, and metals (lead, cadmium, copper, and zinc) in air samples collected at 21 initial education centers in the city of Cuenca. The obtained results indicate low relationships between pollutants and environmental factors, the presence of high variability in pollutant concentrations, and PM10 levels often exceeding the limits established by the World Health Organization and national law.
Análisis de los métodos de interpolación en la distribución espacial de los contaminantes ozono y material particulado menor a 10 micras y su relación con enfermedades alérgicas en niños de 3 a 5 años de edad en el área urbana de la ciudad de Cuenca
(2019-01-28) Guamán Pintado, Pamela Maricela; Mejía Coronel, Julio Danilo
In recent years in the city of Cuenca, industrial activities, construction, and the automotive park have generated an increase in atmospheric pollutant concentrations, causing health problems especially in children to represent a vulnerable population, impacting on diseases such as diseases allergic and increased hypersensitivity to inhaled aeroallergens in the environment. Given that geographic information systems (GIS) represent a fundamental tool for the assessment of air pollution through spatial interpolation. The present investigation determines the method of interpolation that best fits the spatial distribution of the pollutants ozone (O3) and particulate material less than 10 microns (PM10) and its relationship with allergic diseases in children from 3 to 5 years of age. The validation and comparison of the methods allowed us to conclude that the method of inverse distance weighting (IDW), which is an exact and deterministic method, has better results in the estimation of concentrations, compared to Kriging, which is a geostatistical method, a coefficient was obtained of Pearson correlation (r) of 0.6 for O3 and 0.64 for PM10, determining that IDW presents better behavior with atmospheric pollutants. In addition, it was identified that 32% of the study population has a hypersensitivity reaction in the application of skin tests to inhalants, with 52% being the highest percentage of positive reports belonging to the female gender, however no significant relationship was found between contaminants atmospheric with the prevalence of allergic diseases.
Análisis multitemporal del cambio de uso de suelo en la microcuenca del río Tabacay para el periodo 2005-2017
(2018) Bowen Quiroz, Carlos Alejandro; Mejía Coronel, Julio Danilo
Tabacay micro-basin is very important for 27 communes that lives in it, from which they extract resources, develop economic activities and life overall. This micro-basin is also important for Azogues city, which takes water from its rivers for supply the population. This study analyzes land use dynamics and vegetation’s quality during 2005-2017 period, using Landsat satellite images along with geographic information systems, for determining critical areas for management and conservation of Tabacay micro-basin. Four land use classes were determined: agricultural, forestry, urban and moor. Analysis results show that agricultural and urban land use has grown in surface terms, as well as forestry and moor surface has decreased. Moor land use has been the most affected by land use dynamics. In terms of surface, this land use shows a 6 ha/year loss during analysis period, which is equivalent to 54% of its initial surface. Analysis also shows that most affected zone by forest and moor fragmentation and surface loss is micro-basin’s high part, having as main cause of the problem the agricultural frontier expansion and urbanization.
Aplicación de Sistemas de Información Geográfica para la estimación del potencial energético de la biomasa lignocelulósica, en las áreas verdes públicas de la zona urbana de Cuenca
(2019-03-18) Urgilés Urgilés, Enma Cumandá; Yánez Iñiguez, Lucía Irina; Mejía Coronel, Julio Danilo
Nowadays, fossil fuels supply most of the energy demand required by urban centers. For this reason, the development of renewable energies has become in a priority of the strategic plans of different places, such as in Cuenca - Ecuador. The present research seeks to make an initial estimate of the energy potential of the lignocellulosic biomass, which is distributed in the public green areas of the city. In this framework, the application of techniques related to Geographic Information Systems has allowed to estimate the area formed by this renewable resource which has an approximate of 618.76 ha within the study area, where have been identified the species that compose it. In addition, these tools have been very useful to estimate it energy potential, that have 119.49 tep/ha of only 0.38 tep/ha are usable. This scenario raises the importance of conducting research in this line of study, so that in the future lignocellulosic biomass can be considered as part of the endogenous renewable resources that would be incorporated into the local energy matrix.
Aplicación de técnicas de teledetección para el monitoreo de desplazamientos en el barrio las Rosas, cantón Nabón provincia del Azuay
(Universidad de Cuenca, 2023-03-09) Gordillo Bacuilima, Luis Eduardo; Segarra Flores, Juan Carlos; Mejía Coronel, Julio Danilo
In the present degree work, landslide velocity (deformation) values in (LOS) were determined by using satellite images in the Rosas neighborhood, belonging to the Nabón canton; these images are of the radar type and were acquired in a period of time from 2018 to 2022 in both ascending and descending orbit. The images were processed using two methods: DInSAR and PSI/STAMPS, in order to obtain a better view of the behavior of the area before and after the landslide event. A deformation monitoring was implemented to determine the beginning of the event in March 2021, year in which a deformation of 25.06 cm per year in descending orbit and 21.81 cm in ascending orbit was generated with a deformation direction towards the northwest of the neighborhood. The PSI method generated pixel velocity values for the years 2018, 2019 and 2020 with values of -30.08, -14.8 and -29.04 mm/year respectively in descending orbit, orbit that was determined as the best to evaluate the behavior of the neighborhood. In 2021 and 2022, the number of pixels in the Rosas neighborhood was considerably reduced, which is why the velocity values obtained are not representative. These results were correlated with annual rainfall data, the values obtained determined that there is no apparent relationship between the occurrence of rainfall and the ground movement event.
Aplicación de técnicas geoespaciales para la evaluación y predicción del cambio de cobertura del suelo en la parroquia Baños Cuenca-Ecuador
(Universidad de Cuenca, 2023-10-10) Mejía Sánchez, Walter Fernando; Mejía Coronel, Julio Danilo
This study seeks to identify changes in land cover in Baños parish using spatial data and modeling techniques. To achieve this, satellite images from Landsat 5, 7, and 8 sensors were used, classified into the categories of forest cover, shrub and herbaceous vegetation, agricultural land, water bodies, and anthropogenic zones, applying a supervised classification with the logarithm of maximum probability using the SCP complement of the QGIS software. Confusion matrices were used to validate the classification. The MOLUSCE add-on of QGIS software was used to assess and predict land use change. The assessment covered 1991- 2021 and the prediction was projected between 2031-2051 in 10-year intervals. The CA-ANN model was used for the prediction, using geospatial variables such as slopes, DTM, road distances, elevation, distance from rivers and population density. A Pearson correlation analysis was performed to establish the link with land use change. A moderate correlation was found between DTM, road distances and river distance. In this study, in the evaluation, a greater transformation was observed in the categories of shrub and herbaceous vegetation degrading at an annual rate of -0,59%, agricultural land growing at an annual rate of 8,85% and anthropogenic zones growing at a rate of 3,84% annually. The predicted results indicate a loss of 1 128,580 ha of forest in the coming years, offset by an increase of 257.58 ha in anthropogenic zones.
Calidad de agua de las pozas artificiales implementadas para recuperar la rana Gastroteca sp. en Cuenca y bioensayo toxicológico de sus larvas en medios acuáticos con diferentes concentraciones de nitrito de sodio
(2018) León Cajamarca, Paúl Adrián; Mejía Coronel, Julio Danilo
The marsupial frog of Azuay Gastrotheca sp. (ex litonelis, new description pending), in addition to having decreased its population in Cuenca, Ecuador has been little studied. For this reason, a project to implement artificial pools that allow its recovery and study is being executed. In order to contribute with the development of this project, in the present research the pH, conductivity, dissolved oxygen, temperature, nitrites and nitrates of the water of the artificial pools were determined, as well as the percentage of mortality, the concentration lethal medium, the NOAEC and LOAEC of frog larvae Gastroteca sp. subjected to aquatic environments with different concentrations of sodium nitrite. The measurement of related parameters of water quality was made between October 2016 and January 2017; in other hand the bioassay was made between the months of February and March 2017. The values of temperature, pH, conductivity and dissolved oxygen are relatively within the permitted limits. However, there are signs of deterioration in the water quality of the ponds due to the high concentration of nitrites and nitrates at certain points. The average lethal dose of sodium nitrite on stage 26-30 larvae on the Gosner scale of Gastroteca sp. was 42.95 mg / L in 120 hours.
Calidad del agua y variables ambientales en hábitats para anfibios amenazados en la zona urbana de Cuenca
(2017) Tonón Ordóñez, María Dolores; Abad Crespo, Lorena Cristina; Mejía Coronel, Julio Danilo; León, Paúl; Cárdenas, Iván; Pacheco, Belén
Aiming to monitor water quality and Environmental variables of ten (10) artificial habitats for amphibious populations rescue in Cuenca city, physicochemical variables (pH, conductivity, water temperature, dissolved oxygen, nitrites, nitrates, and lead), along with an air quality analysis based on suspended particles determination and meteorological variables (air temperature, relative humidity, atmospheric pressure, and rainfall). The results show certain water quality deterioration signs for some habitats, noticing, however that any sampling spot presented lead concentrations as a heavy metal. Meteorological variables contribute with a habitats’ global vision which allows to relate rainfall events with certain physicochemical attributes along with suspended particles measurements. Even if this research outlines a sampling and analysis protocol of abiotic variables for the habitats, a contemporaneous biological monitoring is urgent to evaluate the functionality of the habitats as conservation sites for urban threatened amphibious.
Caracterización de la isla de calor urbana superficial en la ciudad de Cuenca mediante imágenes satelitales
(Universidad de Cuenca, 2020-06-02) Álvarez Pucha, Hermel Daniel; Mejía Coronel, Julio Danilo
Expansion and uncontrolled urban development have greatly altered the structure of land cover on a global scale. Drastic change of land use causes important secondary effects in the processes of energy balance on the Earth’s surface. Consequently, increasing rates of impermeable surfaces have given place to abnormal patterns of land surface temperature (LST). Areas with relatively high urbanization rates, such as densely populated cities, will probably be more vulnerable to non-desirable impacts of LST. The attractive nature of developed cities, due to potentially high life comfort in terms of transportation, recreation and industrialization, is the main factor that triggers fluctuations in LST values. The formation of surface urban heat islands (SUHI) is closely related with LST patterns and with land use structure. It is important to keep in mind that surface urban heat islands is one of the most common impacts derived from the process of urbanization. The unplanned expansion, mostly of impermeable surfaces can potentially increase the possibility of SUHI phenomenon to happen. Remote sensing technology is a valuable resource for the determination and quantification of the SUHI effect in a determined area. In this study, temporal evaluation of SUHI effect in the city of Cuenca is investigated. The goal of this study is to investigate surface urban heat island as a function of land surface temperature estimated from band 10 of the thermal infrared sensor (TIRS) of Landsat-8 satellite, for the period between 2013 and 2017. The results confirm the existence of a SUHI effect in the city, with variable intensities within specific locations; El Sagrario, Cañaribamba, San Blas, Gil Ramírez, Totoracocha and Sucre are the main areas that are being negatively affected by the consequences of heat islands. These areas have surfaces with the presence of SUHI in more than 50% of their territory, and they present average values of LST, between 34.28 and 35.97 °C. Additionally, the results showed that the average values of LST in the urban area were at least 3.83 to 4.87 °C higher than in undeveloped areas. Also, the positive correlation between LST and NDBI showed an amplifying effect of SUHI magnitude in developed locations, while areas with vegetation predominance attenuated the SUHI effect. On the other hand, urban centers grouped in some parts of the city received the worst ecological evaluation index. Finally, it is indispensable to mention that the adoption of measures to guide urban planning is a necessary alternative to mitigate the effect of heat islands, and to provide thermal comfort in urban zones, thus guaranteeing the quality of life of Cuenca’s population.
Caracterización SIG del uso de la tierra y geomorfología del Macizo del Cajas - Ecuador.
(2019-10-26) Caldas Calle, Ana Ximena; Vázquez Zambrano, Raúl Fernando; Mejía Coronel, Julio Danilo
With the intention of generating through remote sensing useful information for the proper management of the valuable natural resources of southern Ecuador, the preliminary results obtained from the combination of various remote sensing products are presented, as well as the treatment of Lansat 8 satellite images. Three main analyses were carried out in this study: firstly, the vegetation cover and land use in the Cajas Massif Biosphere (MzC) - Ecuador was defined through the application of three supervised classification methods, namely, Maximum Likelihood (MV), Artificial Neural Networks (ANN) and Mahalanobis Distance (MH). Secondly, the depths of 135 lakes and lagoons of the Cajas Antional Park (PNC) were estimated, through the application of the Single Band algorithm (BU). Finally, the analysis of the correlation of limnimetric variables of 145 lakes and lagoons of the PNC and physical variables characterising the surrounding of these lakes and lagoons was performed through a Principal Component Analysis (ACP). The performance of each of the algorithms applied in this study was evaluated, particularly through absolute relative error, as well as through the use of frequency histograms. The evaluation suggested that for the study of land use/coverage, the best image classification product was obtained using the ANN algorithm. On the other hand, of the 135 lakes studied, 89 were classified as shallow lakes and 46 as deep lakes. In the third analysis, the ACP did not suggest an acceptable correlation between the limnimetric and physical variables of the contours of the lakes and lagoons. Based on these results, future work should include the review of the training polygons (ROIs) used in this investigation, as well as the possible reduction of the number of classes considered, in order to minimize the problems of automatic classification due to the superposition of the spectral response for land use/coverage.
Central parks as air quality oases in the tropical Andean city of Quito
(2024) Mejía Coronel, Julio Danilo
rban ecosystem is an intricate agglomeration of human, fauna and flora populations coexisting in natural and artificial environments. As a city develops and expands over time; it may become unbalanced, affecting the quality of ecosystem and urban services and leading to environmental and health problems. Fine particulate matter (particulate matter with aerodynamic diameter ≤2.5 μm - PM2.5) is the air pollutant posing the greatest risk to human health. Quito, the capital city of Ecuador, exhibits a high occurrence of exposure to unhealthy levels of PM2.5 due to a combination of natural and social variables. This study focused on three central parks of this high elevation city, investigating the spatial distribution of PM2.5 concentrations. The particle pollution was then modeled using Normalized Difference Vegetation Index (NDVI). Hazardous instantaneous levels of PM2.5 were consistently found on the edges of the parks along busy avenues, which are also the most frequented areas. This raises concerns about both short- and long-term exposures to toxic traffic pollution in recreational areas within urban dwellings in the global south. The NDVI model successfully predicted the spatial concentrations of PM2.5 in a smaller urban park, suggesting its potential application in other cities. However, further research is required to validate its effectiveness.
Comparación entre modelos digitales de elevación obtenidos de Sentinel-1 y modelo obtenido con LiDAR mediante puntos de control RTK (real time kinematics) en el área urbana del cantón Santa Isabel
(Universidad de Cuenca, 2023-07-24) Pachar Sagbay, Fabián Patricio; Maldonado Ortiz, Andrés Sebastián; Mejía Coronel, Julio Danilo
In the present work, a comparative study was carried out between a digital elevation model generated through LiDAR and Sentinel-1 models, obtained through interferometry applying different resampling methods, corresponding to the year 2021. The study area corresponds to the urban area of the Canton Santa Isabel belonging to the province of Azuay. The study was based on determining the differences between the data obtained through the Sentinel-1 active model and the LiDAR model with the RTK reference points, to determine the feasibility of these models according to their costs. To obtain the satellite images, the Alaska Satellite Facility platform was used, these images had a perpendicular base of 27 m and a temporal period of 12 days, for their processing the InSAR technique was used with the use of SNAP software and geographic information systems. Of the models compared, the DEM corresponding to LiDAR presented a root mean square error (RMSE) value of 0.15 m, while, of the models obtained with interferometry, the DEM with the lowest RMSE value corresponds to the one generated by bicubic resampling, this being 40.01 m and the highest RMSE value being the model belonging to the nearest neighbor resampling with an error of 511 m. According to the results obtained, it was determined that the use of LiDAR for studies or projects that require an elevation model with greater precision is more feasible. This is because the models obtained by interferometry differ significantly from the RTK reference values.
Determinación de algoritmo de estimación de dióxido de azufre (SO2) atmosférico mediante sensores remotos para ecosistemas altoandinos
(2018) Sinchi León, Fanny Belén; Mejía Coronel, Julio Danilo
The high-Andean ecosystems are sensitive to problems caused by the pollution of the air, due to the increase in population density, high concentrations of gases emitted by cars, industries and fuels. Air pollutant gases include the Sulphur Dioxide (SO2) irritant gas to high concentrations that affects the respiratory and cardiovascular system. This research aims to estimate the concentrations of SO2 atmospheric pollutant that has an impact on the deterioration of the air quality of the city of Cuenca with remote sensors. The methodology relates the concentrations of SO2 that were measured in-situ by the network of monitoring quality of air of the public company of mobility, traffic and transport of Cuenca (EMOV-EP) and the information derived from 4 satellite Landsat-8 images that involves sensors: Thermal Infrared Sensor (TIRS) and Thermal Infrared Sensor (TIRS), and through the application of the algorithm of the spectral radiance (AOA) and surface temperatures were estimated concentrations of SO2. The technical relationship between satellite data and measurements data and ground measurements is analyzed by correlation analysis and linear regression analysis, which incorporates generalized additive models (GAM). The results indicate a reliable statistical model, providing coefficients of determination: R² = 0,642, R² = 0,553, R² = 0,694, R² = 0,678. This study can be a valuable tool for decision making by the entities that collaborate in the analysis of air pollution in the city
Determinación de concentración de material particulado 2.5 (PM2.5) con el uso de aeronaves tripuladas a distancia en el área del parque industrial de la ciudad de Cuenca
(Universidad de Cuenca, 2022-01-21) Galarza Poveda, Pedro David; Tinoco Peralta, Diego Fabián; Mejía Coronel, Julio Danilo
In the present degree work, a mathematical model is determined based on the concentration of Particulate Material 2.5 (PM2.5) in the area of the industrial park of the city of Cuenca; Through the identification of an empirical equation, through the information obtained from two multispectral cameras, the first with RGB properties and the second with NIR properties, mounted on a drone (or UAV for Unmanned Aerial Vehicle). The model generated was validated by comparing the values of digital levels of the spectral bands Red, Green, Blue and NIR with the concentrations of the pollutant of the continuous monitoring station belonging to the company EMOV EP (Code: CCA). There were a total of 50 images of the area of interest, acquired every 1 hour, in the industrial park sector of the city of Cuenca. The feasibility of applying this mathematical model in specific areas will be extended, by obtaining an R2 = 0,68, to determine concentrations of PM2.5 without the need to resort to continuous monitoring stations for the pollutant within the city of Cuenca.
Determinación de la adaptabilidad de los anfibios a través de la caracterización en los diez hábitats construidos en la zona urbana de Cuenca
(2018) Salto Sari, José Fernando; Mejía Coronel, Julio Danilo; Abad Crespo, Lorena Cristina
The artificial habitats built in the urban area of the city of Cuenca, is the first attempt to conserve the species Gastrotheca sp, these spaces provide the necessary conditions for the development and protection of this species. However, various processes of natural and anthropic pollution, as well as abrupt changes in environmental conditions, have negatively influenced the adaptation of this species to its new habitat. This problem has generated the need to develop methodologies to characterize the state of artificial habitats. The program of Conservation of Urban Biodiversity, developed by the Environmental Management Commission (CGA), aims to conserve the Marsupial Frog of Azuay (Gastrotheca sp), which is part of the heritage biodiversity of the city of Cuenca. That is why in this work, the abundance of Gastrotheca sp was correlated with the physicochemical parameters of water and environmental conditions in artificial habitats, in the period September - November 2017, with the objective of determining the variables correlated with the adaptability of amphibians. The nitrite parameter and the vegetation cover were the variables that influence the adaptation of the species Gastrotheca sp in artificial habitats.
Determinación de la calidad de aire mediante el uso de líquenes en la ciudad de Cuenca
(Universidad de Cuenca, 2020-01-10) Galarza Molina, Paola Estefanía; Mejía Coronel, Julio Danilo
Air pollution causes various problems in human health and in ecosystems, due to this there is a need to implement various monitoring methods that show the presence of pollutants; The use of bioindicators is a complementary procedure to the regular methods where equipment is used, so its application is important when witnessing environmental stressors. The objective of this project is to determine the air quality in different parts of the city of Cuenca through the use of lichens as bioindicators. The methodology used in this project is based on determining the Atmospheric Purity Index at six monitoring points in the city of Cuenca through the use of a lichen relief mesh in previously selected tree species. Values between 16.2 and 39.2 resulting from the IPA were obtained; and a list of sensitive and tolerant species. An analysis was also carried out based on the number of public transport vehicles, land use and certain air pollutants. Lichens mapping represents a useful method to monitor air quality.
Determinación de la concentración de material particulado sedimentable proveniente del tráfico vehicular en la vía Cuenca-Molleturo y su impacto sobre la vegetación arbustiva en El Parque Nacional Cajas
(2017) Arias Pillajo, Lisseth Paola; Guamán León, Diana Gabriela; Mejía Coronel, Julio Danilo
Cajas National Park (PNC) is located west of Cuenca, Azuay. It is a protected area due to its high ecological richness, becoming a natural hydric regulator. The Cuenca – Molleturo highway crosses the PNC, presenting a high vehicle flow since it is the main connection between Guayaquil and Cuenca, supporting both cities’ economic development. Vehicular traffic releases atmospheric pollutants such as combustion gases or particulate matter (PM 10, PM 2,5 and sedimentary matter), which affect local vegetation in the process of photosynthesis, respiration and transpiration; causing an apparent decrease of endemic biodiversity. The present research is focused on determining the effect of dustfall on the richness and abundance of vegetation, therefore, five main monitoring points were set up along the highway and six transversal points were set to a distance of 50, 150 and 250 meters from both edges of the road (left and right), where dustfall concentration, species richness, and individuals abundance of shrub vegetation were determined for subsequently getting a Spearman correlation between these variables. None of sedimentary material’s concentrations found in the study area exceeded the maximum allowable limits by the Unified Text of Secondary Environmental Legislation (TULSMA), showing the highest concentrations in the points closest to the road. The sampled transects presented high Shannon diversity index values and similar richness between them. Finally, the biological variables correlation with the sedimentary material concentrations showed no significant effect on the richness and abundance of shrub vegetation in the study area.
Determinación de la inversión térmica (IT) a través de imágenes satelitales y su relación con los perfiles de gases obtenidos del satélite Sentinel-5P
(Universidad de Cuenca, 2021-12-16) Cueva Luzón, Erika del Cisne; Faicán Cabrera, Gina Marcela; Mejía Coronel, Julio Danilo
Air quality has become a significant concern for many cities around the world, this because the effects derived from poor air quality cause several problems in people, animals, ecosystems and material resources; in Ecuador, the population′s accelerated growth brings with it the presence of a high vehicular and industrial density; bringing about presence of many pollutants, among the main ones are Ozone (O3), Sulfur Dioxide (SO2), Nitrogen Dioxide (NO2), Carbon Monoxide (CO) and Formaldehyde (HCHO), added to this, various meteorological factors influence the behavior of air pollution, for example, thermal inversions (TI's); which are defined as a phenomenon of increase in air temperature with altitude, being a critical factor that affects air quality because it occurrence in areas and levels with a constant release of pollutants limiting their dispersion and intensifying their concentration. Ecuador lacks instruments that allow measuring the necessary variables to carry out studies on this topic, so satellite images provide us with reliable and easily accessible information to comply with our study, the main objective of our research is to determine if there is a relationship between the phenomenon of thermal inversion and episodes of atmospheric pollution in Ecuador, during the period from December 2018 to January 2020, for which we used daily profile data of Nitrogen Dioxide, Carbon Monoxide, Sulfur Dioxide, Ozone, Formaldehyde, provided by SENTINEL-5P and temperature and pressure profiles provided by ERA 5, which were validated with the in situ data obtained by INAMHI meteorological stations, the thermal inversion was determined by calculating the temperature gradient where the main characteristics of the IT's such as frequency, depth and strength were analyzed, finally the periods of thermal inversion with pollution episodes were correlated, the data validation results confirmed a strong positive correlation between the in situ data and those provided by ERA5, areas were evidenced where up to 320 days with occurrence of IT's throughout the study period were presented, at the regional level, Oriente region presents the largest number of TI concentrating 42% of them, the general average for the strength at the national level is 0.98 ⁰C, the depth of the surface inversions presented a IQR of 200 m to 700 m and for the high inversions the depth was 1237.497m, regarding the relationship with pollutants, in our research strong TI relationships were found with HCHO ( R2 = 0.763) as well as with SO2 ( R2 = 0.680), moderate relationships between TI and O3 ( R2 = 0.570) , in the same way with CO (R2 = 0.577), a weak relationship between TI and NO2 (R2 = 0.262) was found, also our results show significant variations between regions in the concentration of pollutants, periods and levels in which IT's are produced, finally is necessary to mention that, this study is fundamental to know the behavior of pollutants in the presence of meteorological phenomena and provides a database for scientific discussions about integrative strategies to prevent the exposure of the population to these pollutants and mitigate their accumulation thus guaranteeing the quality of life in Ecuador.
Determinación del ruido y partículas contaminantes en el aire ambiente generados por los vehículos en la vía Cuenca-Molleturo y su efecto en la riqueza y abundancia de aves en el parque Nacional Cajas
(2017) Ortega Vásquez, Samantha Estefanía; Plaza Vivanco, Galo Esteban; Mejía Coronel, Julio Danilo
The Cuenca-Molleturo highway is one of the main communication routes between the provinces of Azuay and Guayas. It is a great importance natural reserve, basically due to the biodiversity that it shelters. The present investigation determines the noise and particulate pollutants in the ambient air generated by the vehicles and their effect on the richness and abundance of the birds in Cajas National Park. The measurements were executed perpendicular to the pathway, at 7 points of selection in the function of an altitudinal gradient within a section between the Quinoas Control and Huagrahuma Control. The methodologies to be used for sedimentary material and noise were based on the Reform “Acuerdo 097” pertaining to the Unified Text of Secondary Environmental Legislation of the Environment Ministry, in relation to the census of birds, counting points and transects of 250 meters were performed, and the Shannon index is applied for the measurement of biodiversity. Pearson´s correlation was related to biological variables (birds) with physical variables (height, sedimentary material, noise), where direct and inverse relationships were obtained between them however, the majority of results did not show significant relationships between the variables analyzed.