Intermittent water supply is prevalent among developing countries. Some of its consequences are inequitable water distribution, possible water contamination, wasting water, duplicated costs for consumers and water providers, meter malfunctioning and inconvenience to consumers. There are two major views on how this problem should be addressed. The first considers the problem to be derived from bad administration and management, i.e., there is enough water at the water supply sources but it is not provided continuously to the users, and so a transfer to 24-hour supply by reducing water loss is the only solution. The second view accepts intermittent supply as a reality that will continue for many years in many places and looks for appropriate design and operation methods specific to intermittent water supply that can minimize its negative impacts. Important differences between intermittent and continuous service by water distribution networks are covered by the second case, such as initial network charging and emptying, pressure-dependent water demand, and design pressure. This paper proposes and describes the use of known, free, public domain network models, such as SWMM for modeling initial pipe network charging and emptying, and EPANET for modeling networks with intermittent operations. | La inequitativa distribución del agua, la posible contaminación, las pérdidas, los costos adicionales que se generan para los consumidores y abastecedores del agua, el mal funcionamiento de las redes y la inconveniencia de los usuarios, son algunas de las consecuencias indeseables más comunes que provoca el suministro intermitente. Hay dos opiniones en el ámbito internacional de cómo puede ser considerado el problema. La primera considera que se debe a una mala administración del vital líquido, es decir, hay suficiente agua en las fuentes, pero no se suministra de manera continua a los usuarios, por lo que se requiere trabajar en ello para convertirlo en un suministro de 24 horas a través de la reducción de pérdidas de agua. La otra opinión acepta que el suministro intermitente es una realidad, que en muchas localidades, por muchos años, no se solucionará, por lo que busca trabajar sobre métodos apropiados de diseño y operación específicos para sistemas con operación intermitente, que puedan minimizar sus impactos negativos. Las diferencias más importantes entre la operación de las redes de distribución del agua con servicio intermitente y continuo se engloban en el segundo caso, tales como el llenado inicial y vaciado posterior de las redes, la demanda de agua dependiente de la presión, presión de diseño y otros. En este artículo se propone y ejemplifica el uso de modelos de redes que son conocidos y del dominio público, como el SWMM, para el llenado inicial y vaciado posterior de redes de agua, y el EPANET, para modelar redes con operación intermitente.

Groundwater/surface-water interaction is receiving increasing focus in Africa due to its importance to ecologic systems and sustainability. In South Africa’s 1998 National Water Act (NWA), water-use licenses, including groundwater, are granted only after defining the Reserve, the amount of water needed to supply basic human needs and preserve some ecological integrity. Accurate quantification of groundwater contributions to ecosystems for successful implementation of the NWA proves challenging; many of South Africa’s aquifers are in heterogeneous and anisotropic fractured-rock settings. This paper reviews the current conceptualizations and investigative approaches regarding groundwater/surface-water interactions in the context of South African policies. Some selected pitfall experiences are emphasized. The most common approach in South Africa is estimation of average annual fluxes at the scale of fourth-order catchments (∼500 km2) with baseflow separation techniques and then subtracting the groundwater discharge rate from the recharge rate. This approach might be a good start, but it ignores spatial and temporal variability, potentially missing local impacts associated with production-well placement. As South Africa’s NWA has already been emulated in many countries including Zambia, Zimbabwe and Kenya, the successes and failures of the South African experience dealing with the groundwater/surface-water interaction will be analyzed to guide future policy directions.

In the current world environmental and ecological situation, water issues have become one of the most important topics, not only because of the inequities imposed by water’s uneven geographical distribution through time and space but also by political and economical decisions which truly determine the way we get connected with it. The following essay intends to analyze the water privatization process under the light of three different theoretical proposals: the temporality theory of Fernand Braudel, the horizontal tripartite geographical structure of Peter Taylor and the second nature idea from the critical trend of Geography. These theories will help us understand the spatial implications of the privatization of this basic resource for life, and social reproduction as well as helping us understand the economic and political context in which the water privatization process is evolving. | En el contexto de la actual situación ambiental y ecológica mundial, sin duda uno de los problemas de mayor trascendencia es el referente al agua, no sólo por las fuertes desigualdades que impone su distribución geográfica, tanto en el tiempo como en el espacio, sino, sobre todo, por las decisiones políticas y económicas que determinan nuestra relación social con este vital líquido. Este artículo analiza el proceso de la privatización del agua a la luz de tres ejes teórico-metodológicos: la teoría de las temporalidades de Fernand Braudel, la estructura geográfica horizontal tripartita de Peter Taylor y la noción de la segunda naturaleza derivada de la corriente crítica de la Geografía, que permitirán entender, no sólo las implicaciones geográfico-espaciales de la privatización de un recurso fundamental para la reproducción de la vida y la sociedad, sino comprender cabalmente este proceso en su contexto económico y político mundial.

O tratamento de feridas evoluiu ao longo da história da medicina, com o intuito de se intervir no processo de cicatrização e propiciar mecanismos de proteção ou reparo da lesão. Este trabalho teve por objetivo avaliar o processo de reparação tecidual em coelhos tratados oralmente com água magnetizada e com água-de-coco, visando entender se esse processo terapêutico influencia a reparação de feridas. Utilizaram-se 30 coelhos da raça Nova Zelândia Branca, divididos em 6 grupos com diferentes tratamentos por via oral (água mineral, água magnetizada e água-de-coco). Três desses grupos receberam pomada antibiótica na ferida experimental. Feridas cirúrgicas foram realizadas no dorso dos animais e foram avaliadas clinicamente quanto: edema, halo eritematoso, tempo de cicatrização e tempo de epitelização, aferiu-se também a temperatura retal dos animais. Biopsias foram realizadas nas bordas das feridas para avaliação histopatológica, observação de fibras colágenas (tipos I e III) e de fibras elásticas. Coletas de sangue foram realizadas para análises hematimétricas, leucométricas e plaquetométricas. Monitorou-se consumo de água e de ração dos animais. A temperatura corpórea dos animais se manteve dentro da normalidade (37,1 a 39,4C), assim como todos os parâmetros hematológicos. Os animais que ingeriram água magnetizada e água-de-coco apresentaram o menor tempo de cicatrização e de epitelização e os que receberam água magnetizada apresentaram os maiores valores de fibras elásticas e um maior consumo de água e de ração. O colágeno tipo I foi predominante em todos os grupos, em todas as coletas. A ingestão de água magnetizada e de água-de-coco influenciou o processo reparação tecidual. Porém, mais estudos são necessários para se elucidar o mecanismo de ação deste processo terapêutico. | The wound care has evolved over the history of medicine, in order to intervene in the healing process, to provide protection mechanisms or injury repair. This study aimed to evaluate the process of tissue repair in rabbits treated orally with magnetic water and coconut water, in order to understand whether this therapeutic process influences the skin wounds repairing. Were used 30 rabbits New Zealand White divided into six groups with different oral treatments (mineral water, magnetized water and coconut water), and these, three groups received antibiotic ointment on the experimental wound . Surgical wounds were made on the backs of the animals, which were clinically evaluated, checking the rectal temperature and the characteristics of the wounds: edema, erythematous halo, healing time and time of epithelialization. Tissue biopsies from the edges of the wounds were taken for histological evaluation, observation of collagen fibers (type I and III) and elastic fibers. Blood samples were taken for analysis of red blood cells, leukocytes and platelets. The consumption of water and animal feed were also monitored. The body temperature of the animals remained within the normal range (37.1 to 39.4C), as well as all the hematological parameters. The animals that ingested magnetized water and coconut water showed the lowest time of healing and epithelialization and those that received magnetized water showed the highest values of elastic fibers and increased consumption of water and feed. Collagen type I was predominant in all groups, in all collections. The ingestion of the magnetized water and coconut water influenced the tissue repair process, but more studies are needed to elucidate the mechanism of action of this therapeutic process.

El objetivo de este trabajo fue analizar la producción de biomasa aérea, la eficiencia del uso de agua y el valor nutritivo de alfalfa cultivada aplicando riego con agua residual urbana, agua de perforación y un testigo (precipitaciones), en el Campus de la Universidad Nacional de Rio Cuarto (Córdoba-Argentina). Los tratamientos de riego tuvieron un efecto positivo sobre la producción de biomasa aérea obteniéndose un 24% más de producción de biomasa que en la situación de secano (precipitaciones). Entre los tratamientos con riego también se manifestaron diferencias estadísticamente significativas. La alfalfa regada con aguas residuales urbana supero en un 19% a la cultivada con agua de perforación. La eficiencia del uso del agua por parte del cultivo se incrementó cuando el riego se realizó con aguas residuales urbanas. Además, se determinó que la alfalfa regada con agua residual, supera los valores nutritivos del cultivo que crece en condiciones sin riego; encontrándose 39% más de proteínas, 14% más de digestibilidad e igual porcentaje de energía metabólica. Se puede concluir que el agua residual urbana representa otra posible fuente de agua, factible de ingresar al suelo y estar a disposición para el cultivo de alfalfa.<br>The objective of this study was to analyse the production of alfalfa biomass, the efficiency of water use and the nutritional value of forage, inside an irrigation structure of an experimental facility that uses treated urban wastewater, artesian well water and rainfall, at the campus of the Universidad National de Rio Cuarto (Córdoba-Argentina). The irrigation treatment had a positive effect on the production of biomass of alfalfa. On an average 24% increase in production was observed when compared to dry-land farming. Regarding the quality of the irrigation water, statistical differences in production were observed, the irrigation with urban wastewater produced 19% more than that of well water. The efficiency of the water use by the crop increased when the irrigation was done using urban wastewater. The alfalfa irrigated with wastewater surpasses the nutritional values of the crop in normal field conditions: 39% more proteins, 14% more digestibility and equal percentage of metabolic energy. It is concluded that the urban wastewater represents possible water source for the alfalfa crop.

Expone los conceptos de territorio y cuenca y la necesidad de su ordenamiento o gestión. Asimismo, desarrolla el tema de la gestión integrada del territorio/cuencas y los retos existentes al respecto.

The project began because of the awareness about the deterioration of the environment, which is why this thesis deals with the treatment of industrial effluent coming from the production of olive oil and vegetable water is known that untreated discharges are polluting soils. This project proposes to treat the effluent to reduce the concentrations of contaminants through a new technique that comes from the Electrochemical Engineering, called continuous flow electrocoagulation, in order to use this liquid as irrigation water. OMW polluting compounds are polyphenols which give a bactericidal effect lipid suspension to be dumped on the ground cause the waterproofing of the surface. In this case applied to solve electrocoagulation the issues raised. This method involves the use of electrolytic cells and aluminum metallic electrodes through which electrical current is passed continuously, to produce the decomposition of phenols, transforming them into hydrogen and carbon dioxide, as well as would cause flocculation of lipids on the surface of the effluent for subsequent extraction | El proyecto se inicio en razón de la concientización por el deterioro del medio ambiente, es por ello que esta tesis aborda el tratamiento del efluente industrial que proviene de la elaboración del Aceite de Oliva que se denomina alpechín y que son vertidos sin tratamiento previo contaminando los suelos. Este proyecto propone tratar los efluentes para reducir las concentraciones de sus contaminantes a través de una nueva técnica que proviene de la Ingeniería Electroquímica, que se denomina Electrocoagulación en flujo continuo, con el objeto de poder utilizar este liquido como agua de riego. Los compuestos contaminantes del alpechín son los polifenoles que le confieren un efecto bactericida y lípidos en suspensión que al ser vertidos sobre el suelo producen la impermeabilización de la superficie. En este caso se aplicara la electrocoagulación para solucionara la problemática planteada. Este método involucra el uso de celdas electrolíticas y electrodos metálicos de aluminio a través de los cuales se hace pasar corriente eléctrica continua, que producirá la descomposición de los fenoles, para transformarlos en hidrógeno y dióxido carbono, como así también provocara la floculación de los lípidos sobre la superficie del efluente para su posterior extracción.

Resumen. El flujo de agua en el suelo es calificado como un proceso dinámico que regula reacciones químicas y eventos físicos y biológicos, que a su vez influyen en la nutrición, crecimiento y desarrollo de las plantas; es considerado de interés ambiental, ya que influye en la regulación hidrológica, en la distribución y transmisión de agua, solutos y contaminantes a través de la zona no saturada del suelo. El objetivo de este estudio fue evaluar la dinámica de la humedad volumétrica y del potencial matricial del suelo a lo largo de un periodo de secado, en dos Andisoles, localizados en terrenos de ladera en los municipios de Chinchiná (Caldas) y Quimbaya (Quindío) - Colombia. En cada localidad se seleccionaron y aislaron tres monolitos de suelo de 1,5 m de ancho y 6,0 m de largo, con diferente grado de pendiente (20, 40 y 70%, en Chinchiná y 20, 40 y 75%, en Quimbaya). Se instalaron sensores de humedad y tensiómetros a diferentes profundidades y se monitoreó simultáneamente la humedad volumétrica y el potencial mátrico del suelo durante un periodo de 80 días y se obtuvieron las curvas de secamiento del suelo. El modelo potencial se ajustó mejor al comportamiento de la humedad volumétrica con relación al tiempo; en general, la humedad volumétrica se redujo drásticamente durante la primera etapa del drenaje (0-24 horas); posteriormente, le siguió un drenaje lento en el cual los cambios en la humedad volumétrica a través del tiempo fueron mínimos. La tasa de secamiento del suelo aumentó conforme se incrementó el ángulo de inclinación de la pendiente, lo que se atribuye a una refracción del flujo de agua, considerando que el potencial gravitacional está influido por la inclinación de la pendiente y a la vez indica que la pendiente del terreno afecta el movimiento del agua en el suelo.<br>Abstract. Soil water flux is qualified as a dynamic processes that regulate soil chemical reactions, physical and biological events, which in turn influence plant growth and nutrition. Water flow in soils is considered of environmental importance, since it influences the distribution and transmission of water, solutes and contaminants through the vadose zone. The aim of this study was to evaluate the water dynamics and the matric potential of an Andisols, which were determined over a period of wetting and drying of soil monlith, located on a hillslope area close to Chinchiná (Caldas) and Quimbaya (Quindío) - Colombia. At each site, we selected and isolated three soil monoliths of 1.5 m wide and 6.0 m long, with different slope (20, 40 and 70% in Chinchiná and 20, 40 and 75% in Quimbaya). Soil moisture sensors and tensiometers were installed at different soil depths. The soil volumetric moisture and the matric potential were monitored simultaneously, during 80 days, from which we obtained the drying curves. The resulting potential model fitted the best to the soil volumetric moisture behavior in relation to time. In general, volumetric moisture declined faster during the first drying step (0-24 hours), followed by a slow drainage in which the volumetric moisture changes over time were minimum. The rate of soil drying increased as the increased the slope angle, attributed to a refraction of the water flow, whereas the gravitational potential is influenced by the hillslope of the slope and at the time this indicates that this slope controls the soil water movement.