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Iniciación musical, Pacífica y natural: músicas de agua, aire, páramo y selva | Musical initiation, Pacific and natural: music of water, air, moor and jungle Полный текст
2024
Pinto Núñez, Diego Iván | Anchico Solis, María Elena
El presente trabajo de investigación creación es una propuesta de reconocimiento, apreciación y apropiación de las músicas de marimba del Pacífico sur colombiano en el municipio de Güicán de la Sierra, Boyacá; el cual se desarrolló con el grupo de Iniciación Musical de la Escuela de Música Remembranza de este municipio, para quienes se crearon cinco composiciones musicales basadas en ritmos tradicionales del conjunto de marimba e inspiradas en el paisaje de páramo en el que se encuentra este poblado, así como en la premisa del respeto desde la diferencia, reconociendo las manifestaciones culturales del país desde la niñez. | Universidad El Bosque | Magíster en Músicas Colombianas | Maestría | The present creative research work is a proposal for recognition, appreciation and appropriation of the marimba music of the Colombian South Pacific in the municipality of Güicán de la Sierra, Boyacá; which was developed with the Musical Initiation group of the Remembranza Music School of this municipality, for whom five musical compositions were created based on traditional rhythms of the marimba ensemble and inspired by the paramo landscape in which this town is located, as well as the premise of respect from difference, recognizing the cultural manifestations of the country since childhood.
Показать больше [+] Меньше [-]REACCIONES QUÍMICAS EN AGUA A ALTA TEMPERATURA UTILIZANDO MATEMÁTICAS Y CONCEPTOS DE FÍSICA | CHEMICAL REACTIONS IN HIGH- TEMPERATURE WATER USING MATHEMATICS AND PHYSICS CONCEPTS Полный текст
2023
Delphin Kabey Mwinken
Se ha desarrollado un modelo matemático para el proceso químico primario que ocurre en una descarga eléctrica de 1 J/pulso en el agua. El canal de descarga se divide en dos zonas: el núcleo y la región de recombinación. El núcleo es una parte muy estrecha (aproximadamente 10 μm) del canal. donde tiene lugar la reacción de iniciación a alta temperatura y donde se forma la mayoría de la molécula de hidrógeno y el 47 % del oxigeno molecular. La región de recombinación es una zona de radio de 200 μm donde tienen lugar reacciones adicionales como la formación de peróxido de hidrógeno. La temperatura en el núcleo osciló entre 5000 K en el centro y 2000 en el límite y la presión. Se encontró que el único parámetro ajustable en el sistema era 14 atm. El modelo describe por primera vez cómo se forma el oxígeno molecular en una descarga submarina y también es capaz de describir la estequiometría observada experimentalmente de la formación de H2, O2 y H2O2. También se informan los perfiles de concentración y temperatura dentro del canal de descarga, así. | A mathematical model for the primary chemical process occurring in 1 J/pulse electrical discharge in water has been developed. The discharge channel is divided into two zones: The core and recombination region. The core is a very narrow (ca 10 μm) part of the channel where high temperature initiation reaction take place and where the majority of molecule hydrogen and 47 % of the molecular oxygen are formed. The recombination region is a 200 μm radius zone where additional reactions such as hydrogen peroxide formation take place. The temperature in the core ranged from 5000 K at the centre to 2000 K at the boundary and the pressure. The only adjustable parameter in the system was found to be 14 atm. The model describes for the first time how molecular oxygen is formed in an underwater discharge and it is also able to described the experimental observed stoichiometry of H2, O2 and H2O2 formation. The concentration and temperature profiles inside the discharge channel as well as a general scheme for the water dissociation and molecular species formation are also reported. There have been few studies in the literature that closely examined the different potential influences of High temperature – water (HTW) on chemical reactions. Although the existing reviews and overviews of reactions in aqueous media include some discussion of solvent effects, in none of these reviews is the focal point the role of the reaction medium. This previous treatment of this topic is neither complete nor critical.como un esquema general para la disociación del agua y la formación de especies moleculares.Ha habido pocos estudios en la literatura que examinen de cerca las diferentes influencias potenciales del agua a alta temperatura (HTW) sobre reacciones químicas. Aunque las revisiones existentes y las descripciones generales de las reacciones en medios acuosos incluyen alguna discusión sobre los efectos de los solventes, en ninguna de estas revisiones el punto focal es el papel del medio de reacción. Este tratamiento previo de este tema no es completo ni crítico.
Показать больше [+] Меньше [-]Naturally colored cotton irrigated with saline water at different growth stages | Algodón de color natural regado con agua salina en diferentes etapas de crecimiento Полный текст
2021
Mota, Andygley Fernandes | Gurgel, Marcelo Tavares | Travassos, Kaline Dantas | Miranda, Neyton de Oliveira | da Costa, Lucas Ramos | Ferreira Neto, Miguel | Dias, Nildo da Silva
Naturally colored cotton irrigated with saline water at different growth stages | Algodón de color natural regado con agua salina en diferentes etapas de crecimiento Полный текст
2021
Mota, Andygley Fernandes | Gurgel, Marcelo Tavares | Travassos, Kaline Dantas | Miranda, Neyton de Oliveira | da Costa, Lucas Ramos | Ferreira Neto, Miguel | Dias, Nildo da Silva
This study aimed to evaluate the growth, production, and nutrition of naturally colored cotton (cultivar BRS Verde) irrigated with saline water in different growth stages. The trial was conducted with a randomized block design in which the treatments consisted of three irrigation water salinity levels applied throughout the crop cycle or alternately in three growth stages. The lowest-salinity water was drawn from the Arenito Açu aquifer in the state of Rio Grande do Norte, Brazil; the highest-salinity water was prepared to obtain salinity similar to the water drawn from the Calcário Jandaíra aquifer, and an intermediate salinity was obtained from the mixture of equal volumes of the lowest and highest-salinity waters. The application of the lowest-salinity water is recommended in all growth stages due to the increases of about 19% in cotton growth and 40% in yield compared to the application of intermediate or highest-salinity water. The application of the lowest-salinity water in the vegetative stage and the intermediate-salinity water in the following stages is an alternative to using good quality water throughout the cycle, despite the decreases of about 7% in growth and 16% in yield. The nutrition of cotton plants irrigated with saline water throughout the cycle or in some growth stages was marked by an increase of up to 86% in the cotton leaf sodium content, a decrease in the leaf potassium content of up to 21% and increases between 24% and 188% in leaf micronutrient content when the highest-salinity water replaced that with the lowest salinity. | Este estudio tuvo como objetivo evaluar el crecimiento, producción y nutrición de algodón de color natural (cultivar BRS Verde) regado con agua salina en diferentes etapas de crecimiento. El ensayo se realizó en un diseño de bloques al azar en el que los tratamientos consistieron en tres niveles de salinidad del agua de riego aplicados a lo largo del ciclo del cultivo o alternativamente en tres etapas de crecimiento. El agua de menor salinidad se extrajo del acuífero Arenito Açu en el estado de Rio Grande do Norte, Brasil; el agua de mayor salinidad se preparó para obtener una salinidad similar a la del agua extraída del acuífero Calcário Jandaíra, y la salinidad intermedia se obtuvo de la mezcla de volúmenes iguales de las aguas de menor y mayor salinidad. Se recomienda la aplicación de agua de menor salinidad en todas las etapas de crecimiento debido a los incrementos de aproximadamente 19% en el crecimiento del algodón y 40% en el rendimiento comparado con la aplicación de agua de intermedia o mayor salinidad. La aplicación de agua de menor salinidad en la etapa vegetativa y de agua de salinidad intermedia en las siguientes etapas es una alternativa al uso de agua de buena calidad durante todo el ciclo, a pesar de las disminuciones de alrededor de 7% en el crecimiento y 16% en el rendimiento. La nutrición de las plantas de algodón regadas con agua salina durante todo el ciclo o en algunas etapas de crecimiento estuvo marcada por un aumento de hasta un 86% en el contenido de sodio de la hoja de algodón, una disminución del contenido de potasio de la hoja de hasta un 21% y aumentos entre un 24 y 188% en el contenido de micronutrientes de las hojas cuando el agua de mayor salinidad reemplazó a la de menor salinidad.
Показать больше [+] Меньше [-]Naturally colored cotton irrigated with saline water at different growth stages Полный текст
2021
Andygley Fernandes Mota | Marcelo Tavares Gurgel | Kaline Dantas Travassos | Neyton de Oliveira Miranda | Lucas Ramos da Costa | Miguel Ferreira Neto | Nildo da Silva Dias
This study aimed to evaluate the growth, production, and nutrition of naturally colored cotton (cultivar BRS Verde) irrigated with saline water in different growth stages. The trial was conducted with a randomized block design in which the treatments consisted of three irrigation water salinity levels applied throughout the crop cycle or alternately in three growth stages. The lowest-salinity water was drawn from the Arenito Açu aquifer in the state of Rio Grande do Norte, Brazil; the highest-salinity water was prepared to obtain salinity similar to the water drawn from the Calcário Jandaíra aquifer, and an intermediate salinity was obtained from the mixture of equal volumes of the lowest and highest-salinity waters. The application of the lowest-salinity water is recommended in all growth stages due to the increases of about 19% in cotton growth and 40% in yield compared to the application of intermediate or highest-salinity water. The application of the lowest-salinity water in the vegetative stage and the intermediate-salinity water in the following stages is an alternative to using good quality water throughout the cycle, despite the decreases of about 7% in growth and 16% in yield. The nutrition of cotton plants irrigated with saline water throughout the cycle or in some growth stages was marked by an increase of up to 86% in the cotton leaf sodium content, a decrease in the leaf potassium content of up to 21% and increases between 24% and 188% in leaf micronutrient content when the highest-salinity water replaced that with the lowest salinity.
Показать больше [+] Меньше [-]Naturally colored cotton irrigated with saline water at different growth stages Полный текст
2021
Fernandes Mota, Andygley | Tavares Gurgel, Marcelo | Dantas Travassos, Kaline | Oliveira Miranda, Neyton de | Ramos da Costa, Lucas | Ferreira Neto, Miguel | da Silva Dias, Nildo
ABSTRACT This study aimed to evaluate the growth, production, and nutrition of naturally colored cotton (cultivar BRS Verde) irrigated with saline water in different growth stages. The trial was conducted with a randomized block design in which the treatments consisted of three irrigation water salinity levels applied throughout the crop cycle or alternately in three growth stages. The lowest-salinity water was drawn from the Arenito Açu aquifer in the state of Rio Grande do Norte, Brazil; the highest-salinity water was prepared to obtain salinity similar to the water drawn from the Calcário Jandaíra aquifer, and an intermediate salinity was obtained from the mixture of equal volumes of the lowest and highest-salinity waters. The application of the lowest-salinity water is recommended in all growth stages due to the increases of about 19% in cotton growth and 40% in yield compared to the application of intermediate or highest-salinity water. The application of the lowest-salinity water in the vegetative stage and the intermediate-salinity water in the following stages is an alternative to using good quality water throughout the cycle, despite the decreases of about 7% in growth and 16% in yield. The nutrition of cotton plants irrigated with saline water throughout the cycle or in some growth stages was marked by an increase of up to 86% in the cotton leaf sodium content, a decrease in the leaf potassium content of up to 21% and increases between 24% and 188% in leaf micronutrient content when the highest-salinity water replaced that with the lowest salinity. | RESUMEN Este estudio tuvo como objetivo evaluar el crecimiento, producción y nutrición de algodón de color natural (cultivar BRS Verde) regado con agua salina en diferentes etapas de crecimiento. El ensayo se realizó en un diseño de bloques al azar en el que los tratamientos consistieron en tres niveles de salinidad del agua de riego aplicados a lo largo del ciclo del cultivo o alternativamente en tres etapas de crecimiento. El agua de menor salinidad se extrajo del acuífero Arenito Açu en el estado de Rio Grande do Norte, Brasil; el agua de mayor salinidad se preparó para obtener una salinidad similar a la del agua extraída del acuífero Calcário Jandaíra, y la salinidad intermedia se obtuvo de la mezcla de volúmenes iguales de las aguas de menor y mayor salinidad. Se recomienda la aplicación de agua de menor salinidad en todas las etapas de crecimiento debido a los incrementos de aproximadamente 19% en el crecimiento del algodón y 40% en el rendimiento comparado con la aplicación de agua de intermedia o mayor salinidad. La aplicación de agua de menor salinidad en la etapa vegetativa y de agua de salinidad intermedia en las siguientes etapas es una alternativa al uso de agua de buena calidad durante todo el ciclo, a pesar de las disminuciones de alrededor de 7% en el crecimiento y 16% en el rendimiento. La nutrición de las plantas de algodón regadas con agua salina durante todo el ciclo o en algunas etapas de crecimiento estuvo marcada por un aumento de hasta un 86% en el contenido de sodio de la hoja de algodón, una disminución del contenido de potasio de la hoja de hasta un 21% y aumentos entre un 24 y 188% en el contenido de micronutrientes de las hojas cuando el agua de mayor salinidad reemplazó a la de menor salinidad.
Показать больше [+] Меньше [-]Social–environmental analysis of estuary water quality in a populous urban area | Análise socioambiental da qualidade da água do estuário em área urbana populosa Полный текст
2021
Tseng, Hsiao-Chun | Newton, Alice | Gong, Gwo-Ching | Lin, Chia-Chia
Asia has been experiencing rapid industrialization, urbanization, and economic growth in recent decades. Taiwan was one of the 4 Asian dragons, regions that experienced rapid industrialization and exceptionally high growth rates between the early 1960s and 1990s, but at a high cost to the environment, and thus, it was heavily polluted. Estuaries are highly dynamic and diverse ecosystems that provide multiple ecosystem services that maintain marine ecosystem health and benefit humankind. However, estuaries and the ecosystem services they provide are rapidly degrading due to increasing pressures and changes, especially those in populous, urban areas. Social–environmental analysis integrates scientific information and social activities and thereby provides a comprehensive understanding for the multiparty, joint decision-making processes necessary for successful, sustainable management. In this study, 60 years of economic data and 26 years of water quality data are examined using social–environmental frameworks, the driver-pressurestate-impact-response framework, and the systems approach framework to analyze the management of water quality for an estuary in a populous urban area, the Tamsui River estuary, in Taiwan. Potential societal responses and management measures are identified that can be implemented to reduce human activities, diminish pressure, ameliorate water quality, and enhance the state of the estuarine systems in the Tamsui River and its estuary. The recommended societal responses are increased education, the establishment of community-based river rangers, wetland and mangrove conservation, the development of a circular economy, the implementation of governance measures, and improvements in monitoring and assessments. Improvement of the water quality in the Tamsui River estuary increases the hedonic value of property for people who live near the riverside. Currently, the number of tourists and tourism-based businesses have increased. Nevertheless, improvements in water quality in the Tamsui River estuary bring well-being and benefits that could be further enhanced to increase the cost/benefit relation of the management measures. | MOST 108-2611-M-019-021 | info:eu-repo/semantics/publishedVersion
Показать больше [+] Меньше [-]Caracterización fisicoquímica del agua de la laguna La Vega Escondida, Tampico, Tamaulipas-México - Physicochemical water characterization of La Vega Escondida Lake, Tampico, Tamaulipas-México Полный текст
2019
R. P. González-Dávila | R. Ventura-Houle | F. R. De la Garza-Requena | L. Heyer-Rodríguez
La laguna La Vega Escondida se ubica al Noroeste del municipio de Tampico, Tamaulipas. Es un área natural protegida, que colinda con la zona conurbada de Tampico, Madero y Altamira, que además del beneficio ecológico,es una fuente de abastecimiento de agua potable para la ciudad de Tampico. Por lo cual es importante conocer la composición fisicoquímica del agua de esta laguna, con el fin de proteger tanto el ecosistema como la salud humana. Este estudio, evaluó la concentración de los parámetros fisicoquímicos del agua (pH, conductividad eléctrica, sólidos totales, temperatura, cloruros, dureza, alcalinidad, sulfatos, demanda química de oxígeno y oxígeno disuelto), así como la distribución espacial de éstos dentro de la laguna. Los resultados obtenidos, se compararon con los criterios ecológicos de la calidad del agua (CE-CCA-001-SEMARNAT, 1989) y con la Norma Oficial Mexicana (NOM-127-SSA1-1994), obteniéndose que en los parámetros analizados el agua cumple con la calidad requerida para mantener la vida acuática y captación para consumo humano, excepto en el parámetro de sólidos suspendidos totales (SST). Se observó además que los patrones de distribución espacial de los parámetros fisicoquímicos son heterogéneos y que hay diferencias significativas en el parámetro OD (profundidades), así como en el pH y la CE (puntos de muestreo), al nivel de significancia del 5 %.
Показать больше [+] Меньше [-]Reuso de água e efluente agroindustrial na produção de mudas de gravioleira | Reuse of water and agroindustrial effluent in the production of soursop seedlings Полный текст
2019
Diego Ernani Leite Bezerra (Instituto Federal de Educação, Ciência e Tecnologia da Paraíba) | Ednaldo Barbosa Pereira Junior (Instituto Federal de Educação, Ciência e Tecnologia da Paraíba) | Pedro Lima Filho (Instituto Federal de Educação, Ciência e Tecnologia da Paraíba) | Joserlan Nonato Moreira (Instituto Federal de Educação, Ciência e Tecnologia da Paraíba) | Patrícia Roque Lemos Azevedo (Instituto Federal de Educação, Ciência e Tecnologia da Paraíba)
Reuso de água e efluente agroindustrial na produção de mudas de gravioleira | Reuse of water and agroindustrial effluent in the production of soursop seedlings Полный текст
2019
Diego Ernani Leite Bezerra (Instituto Federal de Educação, Ciência e Tecnologia da Paraíba) | Ednaldo Barbosa Pereira Junior (Instituto Federal de Educação, Ciência e Tecnologia da Paraíba) | Pedro Lima Filho (Instituto Federal de Educação, Ciência e Tecnologia da Paraíba) | Joserlan Nonato Moreira (Instituto Federal de Educação, Ciência e Tecnologia da Paraíba) | Patrícia Roque Lemos Azevedo (Instituto Federal de Educação, Ciência e Tecnologia da Paraíba)
As condições climáticas do semiárido do Nordeste, caracterizadas pela irregularidade das chuvas, conferem à irrigação uma importância fundamental como instrumento que permite a viabilização de uma agricultura produtiva e estável. O presente estudo objetivou-se avaliar o desenvolvimento de mudas de gravioleira a partir do aproveitamento de água de ar condicionado e efluente agroindustrial. A pesquisa foi desenvolvida no setor de produção de mudas do Instituto Federal da Paraíba, Campus Sousa, Unidade São Gonçalo. Utilizou-se o delineamento de blocos inteiramente casualizados, com cinco tratamentos e quatro repetições. Os tratamentos resultaram das seguintes combinações: T1 = 100% Poço Artesiano, T2 =100% Ar Condicionado, T3 = Combinação 50% Ar Condicionado + 50% Poço Artesiano, T4 = Combinação 50% Efluente Agroindustrial + 50% Ar Condicionado e T5 = 100% Efluente Agroindustrial. As mudas de gravioleira foram produzidas em sacos de poliestireno, utilizando Neossolo Flúvico e esterco bovino na proporção (2:1) como substrato. Foram avaliadas as seguintes variáveis: altura de planta, diâmetro de caule, número de folhas, massa verde e seca da parte aérea e raiz e influência nos atributos do solo (pH, P, K, Na, Ca, Mg, MO, PST). Verificou-se que a utilização de água de ar condicionado é uma alternativa viável como fonte de irrigação para as mudas de gravioleira, enquanto que o efluente agroindustrial não se mostrou adequada para este fim visto que influenciou negativamente na maioria das variáveis analisadas. | The climatic conditions of the semiarid region of the northeast, characterized by the deficiency of rainfall, give irrigation a fundamental importance as one of the instruments to enable the viability of more agriculture Productive and with lower risk. Given the panorama of water scarcity, this paper aims to propose the development of soursop seedlings from the utilization of air conditioning and agroindustrial effluent. The research was developed in the seedling production sector located at the Federal Institute of Paraíba, Campus Sousa. A completely randomized block design was used, with five treatments and four replications. The treatments resulted from the following combinations: T1 = 100% Artesian Well, T2 = 100% air conditioning, T3 = combination 50% air conditioning + 50% Artesian Well, T4 = combination 50% agroindustrial effluent + 50% air conditioning and T5 = 100% agroindustrial effluent. Soursop seedlings were produced in plastic bags using Neossol Fluvic and manure in proportion (2:1) as substrate. The following variables were evaluated: plant height, stem diameter, number of leaves, green and dry mass of aerial part and root and influence on soil attributes (PH, P, K, Na, Ca, Mg, MO, PST). After the study, it was verified that the use of air-conditioning water is a good alternative as a source of irrigation for the seedlings of Gravioleira, while the water of agroindustrial effluent was not adequate for this purpose, since it influenced Negatively in most of the variables analyzed.
Показать больше [+] Меньше [-]Reuso de água e efluente agroindustrial na produção de mudas de gravioleira Полный текст
2019
Patrícia Roque Lemos Azevedo | Ednaldo Barbosa Pereira Junior | Joserlan Nonato Moreira | Diego Ernani Leite Bezerra | Pedro Lima Filho
As condições climáticas do semiárido do Nordeste, caracterizadas pela irregularidade das chuvas, conferem à irrigação uma importância fundamental como instrumento que permite a viabilização de uma agricultura produtiva e estável. O presente estudo objetivou-se avaliar o desenvolvimento de mudas de gravioleira a partir do aproveitamento de água de ar condicionado e efluente agroindustrial. A pesquisa foi desenvolvida no setor de produção de mudas do Instituto Federal da Paraíba, Campus Sousa, Unidade São Gonçalo. Utilizou-se o delineamento de blocos inteiramente casualizados, com cinco tratamentos e quatro repetições. Os tratamentos resultaram das seguintes combinações: T1 = 100% Poço Artesiano, T2 =100% Ar Condicionado, T3 = Combinação 50% Ar Condicionado + 50% Poço Artesiano, T4 = Combinação 50% Efluente Agroindustrial + 50% Ar Condicionado e T5 = 100% Efluente Agroindustrial. As mudas de gravioleira foram produzidas em sacos de poliestireno, utilizando Neossolo Flúvico e esterco bovino na proporção (2:1) como substrato. Foram avaliadas as seguintes variáveis: altura de planta, diâmetro de caule, número de folhas, massa verde e seca da parte aérea e raiz e influência nos atributos do solo (pH, P, K, Na, Ca, Mg, MO, PST). Verificou-se que a utilização de água de ar condicionado é uma alternativa viável como fonte de irrigação para as mudas de gravioleira, enquanto que o efluente agroindustrial não se mostrou adequada para este fim visto que influenciou negativamente na maioria das variáveis analisadas.
Показать больше [+] Меньше [-]Impact of a Programme for Water Affordability on Residential Consumption: Implementation of the <em>“Programa Mínimo Vital de Agua Potable”</em> in Bogotá, Colombia Полный текст
2018
Vargas, Laura | Mingoti, Sueli Aparecida | Heller, Léo
Impact of a Programme for Water Affordability on Residential Consumption: Implementation of the <em>“Programa Mínimo Vital de Agua Potable”</em> in Bogotá, Colombia Полный текст
2018
Vargas, Laura | Mingoti, Sueli Aparecida | Heller, Léo
Affordability of services is a determinant for people’s level of access to water. In this study, we analyse the effect of a programme aimed at improving the affordability of water services on users’ water consumption. The programme was implemented in 2012 by the local government of the city of Bogotá, Colombia, intending to provide an essential “lifeline” volume of water to poor households free of charge. Our assessment was carried out with secondary data and used difference-in-difference estimators in a panel data analysis of a two-period sample: 2011 and 2014. The unit of analysis was defined based on the city’s administrative divisions and the socio-economic stratification of residences. Over the period analysed, beneficiaries’ household consumption increased, reaching per capita consumption levels closer to those of the upper strata of users. Results suggest that the programme contributes to increased consumption and equity among users.
Показать больше [+] Меньше [-]Impact of a Programme for Water Affordability on Residential Consumption: Implementation of the “Programa Mínimo Vital de Agua Potable” in Bogotá, Colombia Полный текст
2018
Laura Vargas | Sueli Mingoti | Léo Heller
Affordability of services is a determinant for people’s level of access to water. In this study, we analyse the effect of a programme aimed at improving the affordability of water services on users’ water consumption. The programme was implemented in 2012 by the local government of the city of Bogotá, Colombia, intending to provide an essential “lifeline” volume of water to poor households free of charge. Our assessment was carried out with secondary data and used difference-in-difference estimators in a panel data analysis of a two-period sample: 2011 and 2014. The unit of analysis was defined based on the city’s administrative divisions and the socio-economic stratification of residences. Over the period analysed, beneficiaries’ household consumption increased, reaching per capita consumption levels closer to those of the upper strata of users. Results suggest that the programme contributes to increased consumption and equity among users.
Показать больше [+] Меньше [-]Impact of a Programme for Water Affordability on Residential Consumption: Implementation of the “Programa Mínimo Vital de Agua Potable” in Bogotá, Colombia Полный текст
2018
Laura Vargas | Sueli Aparecida Mingoti | Léo Heller
Affordability of services is a determinant for people’s level of access to water. In this study, we analyse the effect of a programme aimed at improving the affordability of water services on users’ water consumption. The programme was implemented in 2012 by the local government of the city of Bogotá, Colombia, intending to provide an essential “lifeline” volume of water to poor households free of charge. Our assessment was carried out with secondary data and used difference-in-difference estimators in a panel data analysis of a two-period sample: 2011 and 2014. The unit of analysis was defined based on the city’s administrative divisions and the socio-economic stratification of residences. Over the period analysed, beneficiaries’ household consumption increased, reaching per capita consumption levels closer to those of the upper strata of users. Results suggest that the programme contributes to increased consumption and equity among users.
Показать больше [+] Меньше [-]Caracterización de plaguicidas organoclorados en agua y sedimentos en el río Tucutunemo, Venezuela - Characterization of organochlorated pesticides in water and sediments, Tucutunemo River, Venezuela Полный текст
2018
Samuel Cárdenas | Adriana Marquez | Edilberto Guevara | Demetrio Rey
En esta investigación se propone caracterizar plaguicidas organoclorados (POC), y parámetros fisicoquímicos en agua y sedimentos del río Tucutunemo. La información obtenida servirá para desarrollar posteriormente un modelo de transporte de contaminantes. En el año 2015, cada seis meses se colectaron y analizaron 36 muestras simples de agua y sedimentos en tres estaciones de medición. La cuenca del río Tucutunemo tiene una superficie de 116.67 km2, de los cuales 13.75 km2 son suelos agrícolas cultivados. La caracterización de los POC ha sido realizada mediante análisis químico, utilizando un cromatógrafo de gases con detector de captura de electrones, calibrado con 14 POC, de los cuales se detectaron ocho de ellos: aldrín, dieldrín, p.p’-DDD, p.p’-DDE, p.p’-DDT, endrín, o.p’-DDE y o.p’-DDT. En agua, las concentraciones de POC totales han variado desde 0.073 hasta 0.098 µg l-1, por debajo de la regulación de la República Bolivariana de Venezuela, que propone 200 µg L-1. El promedio de las concentraciones de POC más altas detectadas en agua fueron las siguientes: aldrín, 0.021 µg l-1; dieldrín, 0.022 µg L-1; p.p’-DDT, 0.011 µg l-1, rango de valores que, exceptuando el p.p’-DDT, son más bajos que los propuestos por la Environmental Protection Agency (EPA) de 1.300, 0.730 y 0.001 µg l-1, para aldrín, dieldrín y DDT, respectivamente. En los sedimentos, las concentraciones totales variaron de 13.340 a 45.910 µg kg-1, observándose las concentraciones promedio más altas en aldrín, 4.508 µg kg-1 y Dieldrín, 4.169 µg kg-1. En sedimentos, el análisis de varianza detectó diferencias significativas (p < 0.05) para algunas medias de POC.
Показать больше [+] Меньше [-]Water quality of the Grijalva river on the Chiapas - Tabasco border/ Calidad de agua del río Grijalva en la frontera de Chiapas y Tabasco Полный текст
2018
Karim Musálem-Castillejos | Rafaela Laino-Guanes | Ricardo Bello-Mendoza | Mario González-Espinosa | Neptalí Ramírez-Marcial
Water quality of the Grijalva river on the Chiapas - Tabasco border/ Calidad de agua del río Grijalva en la frontera de Chiapas y Tabasco Полный текст
2018
Karim Musálem-Castillejos | Rafaela Laino-Guanes | Ricardo Bello-Mendoza | Mario González-Espinosa | Neptalí Ramírez-Marcial
he objective was to characterize the water quality in a section of the Grijalva River and in some of its tributaries on the border between the States of Chiapas and Tabasco, in the rainy and dry seasons. Twenty-three physical, chemical and microbiological parameters as well as contaminants were determined. The values obtained were compared with the maximum permissible limits (MPLs) for water use and human consumption set out in O cial Mexican standard NOM-127-SSA1-1994, and with the water quality classi cation scale of the Comisión Nacional del Agua (CONAGUA). The water quality in the studied section of the Grijalva River decreases as it descends to more populated areas of the State of Tabasco. Water turbidity and E. coli coliform levels increase, both in the river channels and in sources destined for human consumption. For the other variables evaluated, there are acceptable water quality characteristics, mainly in the dry season, except for mercury, which occurs at levels higher than those recommended. Further studies on the presence of mercury in the Grijalva River basin are recommended.
Показать больше [+] Меньше [-]Water quality of the Grijalva river on the Chiapas - Tabasco border/ Calidad de agua del río Grijalva en la frontera de Chiapas y Tabasco
2018
Musálem-Castillejos, Karim | Laino-Guanes, Rafaela | Bello Mendoza, Ricardo | González-Espinosa, Mario | Ramírez-Marcial, Neptalí
he objective was to characterize the water quality in a section of the Grijalva River and in some of its tributaries on the border between the States of Chiapas and Tabasco, in the rainy and dry seasons. Twenty-three physical, chemical and microbiological parameters as well as contaminants were determined. The values obtained were compared with the maximum permissible limits (MPLs) for water use and human consumption set out in O cial Mexican standard NOM-127-SSA1-1994, and with the water quality classi cation scale of the Comisión Nacional del Agua (CONAGUA). The water quality in the studied section of the Grijalva River decreases as it descends to more populated areas of the State of Tabasco. Water turbidity and E. coli coliform levels increase, both in the river channels and in sources destined for human consumption. For the other variables evaluated, there are acceptable water quality characteristics, mainly in the dry season, except for mercury, which occurs at levels higher than those recommended. Further studies on the presence of mercury in the Grijalva River basin are recommended.
Показать больше [+] Меньше [-]Difusividad del agua en el suelo: un método simple de laboratorio para su determinación | Soil water diffusivity: a simple laboratory method for its determination Полный текст
2017
Lozano, Luis Alberto | Soracco, Carlos Germán | Villarreal, Rafael | Filgueira, Roberto Raúl | Sarli, Guillermo Oliverio
La determinación de la Difusividad (D) del agua en el suelo es importante ya que caracteriza el flujo de agua en condiciones no saturadas. Estimarla es complejo, ya que consume tiempo y generalmente se necesita equipo costoso para hacerlo. Los objetivos de este trabajo fueron: 1- proponer una mejora en el método de Whisler et al. (1968) haciéndolo más simple y robusto, aportando herramientas para probar la validez de la ecuación de Richards en su forma de difusividad y el cumplimiento de los supuestos del modelo y 2- Determinar la D en función del contenido de humedad (θ) y S en un suelo bajo distintas situaciones productivas. Para esto, se tomaron muestras del horizonte superficial de tres lotes contiguos bajo distintos sistemas de manejo (T1: Pastizal natural, T2: Pastura polifítica y T3: Siembra Directa). Las muestras se secaron, tamizaron por 2 mm y se empaquetaron en columnas de PVC de 70 cm de largo y 10 cm de diámetro interno. Las columnas de suelo se sometieron a infiltración horizontal y se determinó la D a distintos valores de θ y la S. Se utilizaron sensores de humedad de capacitancia de bajo costo en puntos fijos de la columna. Los resultados encontrados muestran la validez de la metodología para los suelos estudiados. En cuanto a la influencia del manejo, se encontraron diferencias significativas en los valores de D entre los tratamientos. El T3 presentó mayores valores de D a todas las humedades, y de S, que T1 y T2 (los valores de D estuvieron entre 0,00033 y 0,0321 cm<sup>2</sup> s<sup>-1</sup>), lo que indica mayor facilidad para transmitir agua en condiciones no saturadas en el manejo agrícola, lo cual se atribuyó a la influencia negativa del pisoteo animal. La metodología propuesta permitió estimar de manera consistente, simple y de bajo costo la D y estudiar su relación con el manejo del suelo. | Soil water diffusivity (D) determination is important as this hydraulic property is fundamental in order to characterize unsaturated water and solute transport in soils. Determination of this property is complex, time consuming, and requires quite expensive instruments. The objectives of this work were: i) to propose a simpler and more robust method based on an improvement of Whisler et al. (1968) to determine the soil water diffusivity function and ii) to determine D and sorptivity (S) in a soil under different management systems. Soil A-horizon was sampled under three management systems (T1: Natural grassland, T2: Polyphitic Pasture, and T3: no tillage). The samples were sieved through a 2 mm mesh, and afterwards packed into 70 cm long and 10 cm diameter columns. The columns were analyzed under horizontal infiltration and D was determined as a function of soil water content that varied in function of time for fixed positions along the column, these latter were obtained from low cost soil moisture capacitance sensors. The results showed that the proposed methodology was valid for the studied soils. The soil management system significantly affected D and S values. D values corresponding to T3 were greater compared to T1 and T2 (D values ranged between 0.00033 and 0.0321 cm<sup>2</sup> s<sup>-1</sup>) implying that these soils had the ability to transmit water easier under non-saturated conditions than under grazing. In conclusion, the proposed methodology in this work allowed to determine D in a simple and low cost way, and to analyze the influence of soil management systems on this property. | Facultad de Ciencias Agrarias y Forestales
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