No Submédio do Vale do São Francisco, os problemas decorrentes da morte descendente e do declínio da videira, causados pelo fungo Lasiodiplodia theobromae, são crescentes. O patógeno afeta os parreirais já implantados, a produção de mudas e a formação de novas áreas de produção. Com o objetivo de avaliar o efeito do tratamento da água quente na viabilidade do fungo L. theobromae, para potencial uso como ferramenta no manejo fitossanitário de produção de mudas de videira, foi realizado um experimento in vitro, utilizando diferentes combinações de temperatura (50 oC, 52 oC, 54 oC, 56 oC e 60 oC) e tempo de exposição (30,40, 50 e 60 minutos), frente a dois isolados do patógeno. O crescimento micelial foi filtrado, seco em estufa e, posteriormente, pesado. Os dados de massa de matéria seca (g) foram submetidos à análise de variância e teste de comparação de médias. Houve interação significativa para os dois fatores testados, para ambos os isolados (P≤0,05). Não houve crescimento do patógeno em temperaturas acima de 52 oC e tempo de exposição superior a 40 minutos.

Resumen Objetivo: Determinar, mediante un estudio empírico, cómo el uso del agua residual que recibe la región del Valle del Mezquital en Hidalgo, desde hace más de cien años, proveniente de la Zona Metropolitana del Valle de México, sin un tratamiento previo, configuró el espacio agrícola en esta región no apta para esta actividad por sus condiciones geográficas y climáticas. Metodología: Se realizó una revisión de la literatura con respecto a la problemática del agua residual en combinación con información cuantitativa de diferentes instituciones para realizar un análisis desde la disciplina de economía ecológica que identifique los factores que la convierten en el detonante de importantes problemáticas sociales y ambientales. Resultado: Se identificó que el uso de este tipo de agua en el sector agrícola de la región, contiene una alta carga contaminante compuesta por material orgánico, algunos metales, bacterias y detergentes, lo cual permitió el desarrollo del sector aunado a severos problemas de salud pública y degradación de suelos. Limitaciones: Faltan estudios recientes que documenten las implicaciones en la salud de los habitantes de la región y en los ecosistemas. Conclusiones: La reconfiguración de los espacios para determinar regiones no necesariamente conlleva un beneficio social y ambiental, muchas veces implica el detrimento de la calidad de vida y degradación de los ecosistemas. No obstante, para parte de los habitantes de la región el uso de este tipo de aguas les has permitido salir de las condiciones de marginalidad en las cuales vivían. | Abstract Objective: Determine with an empirical study that the use of wastewater received by the agricultural sector of the Mezquital Valley in Hidalgo for more than one hundred years, from the Metropolitan Zone of the Valley of Mexico without prior treatment, configured the agricultural space in this region not suitable for this activity due to its geographical and climatic conditions. Methodology: A review of the literature of the problem of wastewater in combination with quantitative information from different institutions to make and an analysis to the ecological economy discipline that identifies the factors that make it the trigger of important social and environmental problems. Results: It was identified that the use of this type of water in the agricultural sector of the region, contains a high pollutant load composed of organic material, some metals, bacteria and detergents, which allowed the development of the sector together with severe public health problems and soil degradation. Limitations: Lack of recent studies that document the implications on the health of the population and ecosystems of the region. Conclusions: The reconfiguration of spaces to determine regions does not necessarily imply social and environmental benefit in some cases it implies the detriment of the quality of life and degradation of the ecosystems. However, for part of the population of the region the use of this water has allowed them to leave the conditions of marginality in which they lived.

Travel time is one of the important criteria in the design of managed aquifer recharge systems for securing good drinking water quality. Traditionally, groundwater travel time has been modelled without considering the effect of temperature. In this study, a cross-sectional heat transport model was constructed for the Amsterdam dune filtration system (in the Netherlands) to analyse the effect of temperature on groundwater travel times. A groundwater flow model, a chloride transport model, and a heat transport model were iteratively calibrated with measured groundwater levels, chloride concentrations, and temperature series in order to improve model calibration and reduce model uncertainty. The coupled flow and heat transport model with temperature-dependent density and viscosity provided more accurate estimation of travel times. The results show that seasonal temperature fluctuations in the source water in the infiltration pond cause temperature variations in the shallow groundwater. Viscosity is more sensitive to temperature changes and has a larger effect on groundwater travel times. Groundwater travel time in the shallow sand aquifer increases from 60 days when computed with the traditional groundwater flow model to 73 days in the winter season and 95 days in the summer season when computed with the coupled model. Longer travel time is beneficial for water quality improvement. Thus, it is important to consider the effect of temperature variations on groundwater travel times for the design and operation of managed aquifer recharge systems.

Mandalay is a major city in central Myanmar with a high urban population and which lacks a central wastewater management system, a solid waste disposal process, and access to treated drinking water. The purpose of this study is to investigate the groundwater quality of local dug wells and tube wells, determine quantitative data on characteristics of the Amarapura Aquifer, and compare seasonal variations in groundwater flow and quality. Water samples were collected during the dry and wet seasons, then analyzed for major ion chemistry using ion chromatography to identify indicators of wastewater contamination transport to the shallow aquifer and to compare seasonal variations in groundwater chemistry. An open-source analytic element model, GFLOW, was used to describe the physical hydrogeology and to determine groundwater flow characteristics in the aquifer. Hydrogeochemistry data and numerical groundwater flow models provide evidence that the Amarapura Aquifer is susceptible to contamination from anthropogenic sources. The dominant water types in most dug wells and tube wells is Na-Cl, but there is no known geologic source of NaCl near Mandalay. Many of these wells also contain water with high electrical conductivity, chloride, nitrate, ammonium, and E. coli. Physical measurements and GFLOW characterize groundwater flow directions predominantly towards the Irrawaddy River and with average linear velocities ranging from 1.76 × 10⁻² m/day (2.04 × 10⁻⁷ m/s) to 9.25 m/day (1.07 × 10⁻⁴ m/s). This is the first hydrogeological characterization conducted in Myanmar.

Este documento de investigación evoca los aspectos sobre la explotación de hidrocarburos mediante la técnica de fracturamiento hidráulico en Colombia, en cuanto a implicaciones ambientales a considerar y cómo esta técnica puede afectar el recurso hídrico, específicamente el caudal del río de donde se captará el agua necesaria para las actividades. El área de estudio se remite a la cuenca del Río Lebrija. Para determinar la oferta hídrica, el caudal disponible y caudal ambiental de la cuenca, se utilizó el modelo hidrológico del Soil Conservation Services. A partir de la curva de duración de caudales se definió la capacidad de abastecimiento de agua para las actividades de fracturamiento hidráulico en el municipio de San Martín, Cesar, el cual se encuentra al norte de la cuenca del Río Lebrija. Se estableció que el caudal de la cuenca del Río Lebrija puede abastecer las actividades de fracturamiento hidráulico sin afectar el caudal ambiental del río, se observó también que la temporada más apropiada para la captación de aguas se ubica entre abril y octubre. | This research paper evokes aspects of hydrocarbon exploitation through the hydraulic fracturing technique in Colombia, in terms of environmental implications to consider and how this technique can affect the water resources, specifically the flow of the river from where the water needed for the activities will be extracted. The study area is referred to the Lebrija River basin. The hydrological model of the Soil Conservation Services and the water supply of the Lebrija River basin were used to determine the available flow and environmental flow of the basin. From the flow duration curve, the water supply capacity was defined for hydraulic fracture activities in the municipality of San Martín, Cesar, which is at north of the Lebrija River basin. It was established that the flow of the Lebrija River basin can supply the hydraulic fracture activities without affecting the environmental flow of the river, it was also noted that the most appropriate season for water collection is between April and October.

As águas subterrâneas revelam-se dos recursos mais importantes e vitais, uma vez que englobam um conjunto de reservas relevantes que constituem os aquíferos, sendo uma fonte de água potável. Desta forma, assumem uma função determinante na sobrevivência dos ecossistemas, pelo que é necessário alcançar uma gestão sustentável deste recurso. O crescimento rápido e persistente da população humana tem como resultado uma crescente pressão territorial, trazendo consigo a necessidade de aumentar as zonas urbanas ou, muitas vezes, de proceder à dispersão do edificado. Tendo em conta a importância vital das águas subterrâneas, é essencial que estas sejam protegidas da pressão territorial e que a sua utilização ocorra de forma prudente. Considerando que o aumento do número de captações de água subterrânea pode constituir uma ameaça para os aquíferos, a presente dissertação tem como objetivo principal perceber até que ponto o licenciamento de captações de água subterrânea está a contribuir para o aumento da dispersão do edificado. Para a análise utilizaram-se como casos de estudo as bacias hidrográficas dos rios Leça, Vizela, Antuã e Cértima. Os resultados mostram a existência de um aumento significativo do número de captações de água subterrânea ao longo dos anos, sendo a maioria destas concretizada através de furos e utilizadas para rega. As áreas dos casos de estudo analisadas revelam que o aumento da dispersão do edificado não é acompanhado pela dispersão das captações de água subterrânea. No entanto, não é possível concluir que o licenciamento de captações de água subterrânea não está a contribuir para o aumento da dispersão do edificado, uma vez que as imagens analisadas apenas representam uma fração muito pequena da área total de cada bacia hidrográfica em estudo. | Groundwater is one of the most important and vital resources since it includes a number of relevant reservoirs that originates aquifers, being a source of potable water. This way, they play a significant role in the survival of ecosystems, therefore it is necessary to achieve a sustainable management of this resource. The fast and persistent growth of the human population has as result a growing territorial pressure, creating the need to increase the urban areas or, more often, proceeding to the dispersion of the built. Considering the vital importance of the groundwater, it is essential that they are protected from territorial pressure, and that their use happens in a cautious way. Bearing in mind that the increase in the number of groundwater abstractions may pose a threat to aquifers, the main objective of this dissertation is to understand the extent to which the licensing of groundwater abstraction is contributing to an increase in the dispersion of the built. The river basins of Leça, Vizela, Antuã and Cértima where used for the analysis of this study. The results show the existence of a significant increase of the number of groundwater abstractions along the years, being most of these achieved through holes and used for watering. The analysed areas reveal that the increase of the dispersion of the built is not accompanied by the dispersion of the groundwater abstractions. However, it is not possible to conclude that groundwater abstractions licensing is not contributing for the increase of the dispersion of the built, once the analysed images merely represent a very small fraction of the total area of each hydrographical basin in study. | Mestrado em Engenharia do Ambiente

Se estudia el desarrollo histórico de uno de los sistemas de riegos más extensos de España y con mayor trayectoria histórica, que en 2018 alcanzó el centenario. El artículo se adentra en el análisis de la dinámica histórico-institucional del sistema, desde su formación bajo la forma de sociedad anónima de riegos, a su consolidación como comunidad de regantes primero de base y luego derivada: Comunidad General. Junto al devenir institucional se analiza la evolución de los títulos de aprovechamiento que sustentan el modelo, que en un primer momento evidencian la estrecha relación entre la producción de hidroelectricidad y el regadío, y que en épocas más recientes se caracterizan por la desagregación de ambos negocios y la creación de nuevas fuentes de suministro, entre las que destaca el Trasvase Tajo-Segura, la reutilización de aguas regeneradas y los caudales desalados. Todo ello enriquecido con la creación de un humedal artificial del máximo valor ambiental, el "Hondo de Elche", que se concibe como pantano regulador de las aguas sobrantes del Segura. En definitiva, un modelo histórico de gobernanza del agua del mayor interés tanto desde el punto de vista institucional como agrario, socioeconómico, hidráulico y ambiental.