Most studies of fractured-rock aquifers are about analytical models used for evaluating aquifer tests or numerical methods for describing groundwater flow, but there have been few investigations on how to estimate the reliable long-term drought yields of individual hard-rock wells. During the drought period of 1998 to 2002, many municipal water suppliers in the Piedmont/Blue Ridge areas of central Maryland (USA) had to institute water restrictions due to declining well yields. Previous estimates of the yields of those wells were commonly based on extrapolating drawdowns, measured during short-term single-well hydraulic pumping tests, to the first primary water-bearing fracture in a well. The extrapolations were often made from pseudo-equilibrium phases, frequently resulting in substantially over-estimated well yields. The methods developed in the present study to predict yields consist of extrapolating drawdown data from infinite acting radial flow periods or by fitting type curves of other conceptual models to the data, using diagnostic plots, inverse analysis and derivative analysis. Available drawdowns were determined by the positions of transition zones in crystalline rocks or thin-bedded consolidated sandstone/limestone layers (reservoir rocks). Aquifer dewatering effects were detected by type-curve matching of step-test data or by breaks in the drawdown curves constructed from hydraulic tests. Operational data were then used to confirm the predicted yields and compared to regional groundwater levels to determine seasonal variations in well yields. Such well yield estimates are needed by hydrogeologists and water engineers for the engineering design of water systems, but should be verified by the collection of long-term monitoring data.

Os recentes avanços das tecnologias de sensores e automação de sistemas tornaram possível o desenvolvimento de máquinas e implementos para aplicação de insumos à taxa variável, e viabilizaram o desenvolvimento da agricultura de precisão. Um componente essencial da agricultura de precisão é o monitor de produtividade, sistema composto por diversos sensores com objetivo de medir a produtividade em cada ponto da lavoura, durante a colheita. Os dados medidos no campo permitem gerar mapas de produtividade, auxiliando ao produtor a planejar a safra seguinte e decidir qual o melhor uso/manejo de sua terra. No Brasil, apenas as máquinas colhedoras autopropelidas são comercializadas com monitores de produtividade sendo empregadas apenas em grandes fazendas, devido ao seu elevado custo de aquisição. Dentre os componentes do monitor de produtividade destacam-se o sensor de teor de água. O sensor de massa específica aparente geralmente não é utilizado em máquinas com base em fluxo volumétrico, o fluxo mássico é determinado utilizando uma massa específica única para todo o campo fornecida pelo usuário do sistema, o que reduz a exatidão da determinação da produtividade. Nesse sentido, esse trabalho foi realizado com o objetivo de desenvolver um sistema de baixo custo, capaz de determinar a massa específica aparente e o teor de água para grãos de milho e feijão. Além disso, o sistema desenvolvido deveria apresentar potencial para implementação em monitores de produtividade de colhedoras tracionadas por tratores. O sistema proposto foi desenvolvido e calibrado no laboratório de mecanização agrícola da Universidade Federal de Viçosa. Um conjunto de células de carga e um recipiente de volume conhecido foram utilizados para desenvolver um sensor de massa específica aparente. Já o sensor de teor de água foi desenvolvido com base em duas metodologias distintas: método dielétrico e método que utilizava equações de equilíbrio higroscópico. Para construção do sensor com base no método dielétrico foi utilizado um par de eletrodos cilíndricos. O sensor com base na segunda metodologia foi desenvolvido utilizando as medições realizadas por um sensor de temperatura de umidade relativa do ar modelo AM2302. O sistema desenvolvido processava os dados no microcontrolador Arduino UNO ® , armazenava-os em um cartão de memória e informava ao usuário os valores medidos por meio de um display LCD. Ambos os sensores foram validados utilizando-se grãos de milho e de feijão e tiveram seus respectivos tempos de resposta determinados. O sensor de massa específica aparente apresentou erro quadrático médio (RMSE) de 14,58 e 16,17 kg m -3 para os grãos de feijão e de milho, respectivamente. Já as medições teor de água pelo sensor que utilizou o método dielétrico resultou em RMSE de 0,46 e 1,53 %, para os grãos de feijão e de milho, respectivamente. O RMSE pelo método das equações de equilíbrio higroscópico foi de 1,36 %. O tempo de resposta foi de 8 s para o sensor de massa específica aparente; 63 s para o sensor de teor de água pelo método dielétrico; e 41 min para o sensor de teor de água pelo método as equações de equilíbrio higroscópico. Foi construído um equipamento de fácil replicação e atualização, com custo total de construção de R$ 314,74. O equipamento desenvolvido era condizente com a abordagem de código aberto, na qual o compartilhamento de informações sobre hardware e software de equipamentos facilita a implementação e a melhoria contínua das tecnologias existentes. | Recent advances in sensor technologies and systems automation have allowed the development of machines and implements for variable rate application and they have enabled the development of precision agriculture. An essential component of precision agriculture is the yield monitor, a system composed of several sensors to measure yield at each point of the field during harvesting. The data measured in the field allow generating yield maps, helping the producer to plan the next crop and to decide which is the best management for the land. In Brazil, only self-propelled harvesters are sold with yield monitors being used only on huge farms, due to their high acquisition cost. One of the most important components of a yield monitor is the moisture content sensor. The bulk density sensor is generally not used in volumetric flow-based machines, the mass flow is determined using a unique test weight value for the entire field. This value is provided by the user of the system, which reduces the accuracy of the determination of yield. Therefore, the objective of this work was to develop a low-cost system capable of determining the bulk density and moisture content for corn and beans. In addition, the developed system should present potential for implementation in yield monitors of harvesters pulled by tractors. The proposed system was developed and calibrated in the agricultural mechanization laboratory of the Federal University of Viçosa. A set of load cells and a container of known volume was used to develop the bulk density sensor. The moisture content sensor was developed based on two different approaches: using the dielectric method and using the equilibrium moisture content equations. For the construction of the sensor based on the dielectric method, a pair of cylindrical electrodes was used. The sensor based on the second methodology was developed using measurements made by an air relative humidity and temperature sensor, model AM2302. The developed system processed the data in the Arduino UNO ® microcontroller, stored the data in a memory card and informed the user the measured values through an LCD display.Both sensors were validated using maize and bean grains and had their respective response times determined. The bulk density sensor showed a root mean square error of 14.58 and 16.17 kg m -3 for bean and maize grains, respectively. The measurements of moisture content by the sensor using the dielectric method resulted in errors of 0.46 and 1.53 % for beans and maize, respectively. The error by the equilibrium moisture content equation method was 1.36 %. The response time was determined as 8 s for the bulk density sensor; 63 s for the moisture content sensor by the dielectric method; and 41 min for the moisture content sensor by the equilibrium moisture content equations method. It was built an equipment of easy replication and update, with a total development cost of 314.74 BRL (approximately 80.00 USD). The equipment developed was consistent with the open source approach in which sharing hardware and software equipment information facilitates the implementation and continuous improvement of existing technologies.

This work proposes a methodology for sugarcane expansion monitoring and its possible impacts in the regional hydric dynamic through the real evapotranspiration estimation (ET) based on Terra/Modis satellite data. The methodological approach is based on a systematic and automatic land use mapping that uses a sequence of temporal profiles Vegetation Index (NDVI) built with Modis data JONATHAN (2005). Previous Studies (MEIRELLES et al, 2006 JONATHAN et al 2008); as well as some preliminaries results developed on the scope of this work, shown the applicability of the proposed method as a tool for regional monitoring land use dynamic and its impacts. The real evapotranspiration is calculated through SEBAL algorithm (Surface Energy Balance for Land) developed by BASTIAANSSEN (1995) for energy balance estimation. The study area is the southern portion of Goias state in Brazil, where the sugar cane expansion has being increasing drastically in the last decades. O objetivo deste trabalho é apresentar uma combinação de procedimentos metodológicos, relacionados à distinção da cultura da cana-de-açúcar por meio do aperfeiçoamento de uma metodologia de classificação automática do uso do solo, desenvolvida por JONATHAN (2005, (a) e (b)), e da utilização do Modelo SEBAL para a estimativa da ET real, ambos a partir de dados do sensor MODIS/Aqua.

El presente artículo presenta una comparación multitemporal del cambio en la cobertura vegetal de los últimos 26 años del espejo de agua y el área correspondiente a la cuenca de la laguna de Tota. Implementando el uso de imágenes satelitales landsat y un procesamiento fundamentado en la teledetección como técnica para realizar seguimiento ambiental, generación de mapas y planeación territorial. Los resultados de este articulo evidenciaron un aumento de zonas de producción agrícola especialmente cultivos de cebolla larga, así como un incremento de zonas urbanas lo cual refleja la progresiva presión antrópica sobre el ecosistema, la disminución de zonas forestales y la perdida de superficie del lago por procesos de desecación que responde a la discrepancia entre las actividades productivas y los sistemas naturales. | this article conducted a multitemporal comparison of the change in vegetation coverage of the last 26 years in the water mirror and the corresponding area to the Tota lagoon basin. The implementation of Landsat satellite images and remote sensing processing shows to be an effective technique for environmental monitoring, generation of maps and territorial planning. The results of this article showed an increase in areas of agricultural production, especially long onion crops. It showed an increase in urban areas which evidences the progressive anthropogenic pressure on the ecosystem; a decrease of forest areas and the loss of surface of the lake due to processes of desiccation that responds to the discrepancy between productive activities and natural systems.

[SPA] Este estudio evalúa los aspectos agronómicos que deben ser considerados en el uso del agua marina desalada (DSW) en la cuenca del río Segura (SRB), dentro de un estudio de marco de orden superior, donde se analizan aspectos de planificación, ambientales (agua y energía), huella de carbono y económicos, y donde se describe y examina desde una perspectiva crítica el desarrollo y ejecución del abastecimiento del agua desalada para la agricultura en la cuenca del Segura. En este sentido, para la caracterización de la química del agua desalada, se han analizado datos de salinidad, nutrientes, elementos fitotóxicos, SAR y estabilidad química y pH de las cuatro principales desaladoras (IDAM) que abastecen a las zonas regables (Águilas, Valdelentisco, Torrevieja y Escombreras), realizando una comparación con el Trasvase Tajo Segura (TSW) y el agua de salobre de pozos (BGW). Este estudio sienta las bases de la caracterización química para las estrategias de mezcla que deben ser modelizadas según las diferentes zonas regables y tipología de cultivo de la cuenca. [ENG] Este estudio evalúa los aspectos agronómicos que deben ser considerados en el uso del agua marina desalada (DSW) en la cuenca del río Segura (SRB), dentro de un estudio de marco de orden superior, donde se analizan aspectos de planificación, ambientales (agua y energía), huella de carbono y económicos, y donde se describe y examina desde una perspectiva crítica el desarrollo y ejecución del abastecimiento del agua desalada para la agricultura en la cuenca del Segura. En este sentido, para la caracterización de la química del agua desalada, se han analizado datos de salinidad, nutrientes, elementos fitotóxicos, SAR y estabilidad química y pH de las cuatro principales desaladoras (IDAM) que abastecen a las zonas regables (Águilas, Valdelentisco, Torrevieja y Escombreras), realizando una comparación con el Trasvase Tajo Segura (TSW) y el agua de salobre de pozos (BGW). Este estudio sienta las bases de la caracterización química para las estrategias de mezcla que deben ser modelizadas según las diferentes zonas regables y tipología de cultivo de la cuenca. | Esta investigación ha sido financiada por el Programa de Apoyo a la Investigación de la Fundación Séneca-Agencia de Ciencia y Tecnología de la Región de Murcia a través del proyecto 19280/PI/14. Agradecimientos también a la Cátedra Trasvase y sostenibilidad – José Manuel Claver Valderas, y a los datos suministrados por ACUAMED.

56 p. | 59042

Groundwater-level fluctuations at a large scale have a significant effect on the preservation and restoration of vegetation. This study determined suitable groundwater depth within which natural vegetation grows well, and analysed the effect of groundwater regulation on vegetation restoration in Tianjin City, northern China. Normal and lognormal distributions were used to fit the curve of the relation between vegetation and groundwater depth. The groundwater depth range corresponding to the higher frequency of vegetation distribution was regarded as the ‘suitable water depth’ range for vegetation growth. The suitable groundwater depth for shrub growth was 3–5 m and for grass growth 1–3 m. A groundwater flow model predicted the future changes of groundwater depths in the vegetation distribution area under the condition that the current levels of groundwater extraction are maintained. The results showed that there is potential for the extraction of groundwater in shrubland areas, but for grassland areas the water-table elevation showed a downward trend, meaning that water shortages in some areas may be more severe in the future. Finally, based on the current groundwater extraction regime, two regulation schemes were developed: (1) for shrubland, groundwater extraction was reduced by 10% in the ecological water deficit areas, and extraction was increased by 10% in the ecological water surplus and suitable areas, and (2) for grassland, groundwater recharge was increased by the restoration of the wetland areas. In conclusion, the groundwater depths in most of the area would be more suitable for vegetation growth under the regulation schemes.

Proyecto de Graduación (Licenciatura en Ingeniería Ambiental) Instituto Tecnológico de Costa Rica, Escuela de Química, 2018 | Watersheds in Costa Rica show a deterioration in their water quality, associated to the lack of an urban development planning to define the uses for each area. This planning absence leads to inadequate uses in areas of high ecological fragility. The use of a water quality predictive model based on socio-environmental variables allowed the evaluation of different scenarios and the impact of socio-environmental changes on water quality in the future, in the sub-basin of the Rincón River, an area selected as a sample within the Golfo Dulce Forest Reserve. The model used was developed by researchers at the ITCR and evaluates the quality of water by analyzing socio-environmental variables, such as population density and land use. According to the evaluation of scenarios, the increase of the uses for pastures or fallow land does not harm the quality of the water if kept below 25% of the total area. It was found that the increase in permanent plantings area and the loss of forest does affect the quality of the water negatively. It was also found that the decision criterion of greater weight for environmental management, oriented to preserve water quality as class 2, obeys to maintain the forest cover and to incentive economic activities that can coexist with the standing forest. In addition, it was determined that, through the development of relevant activities, a decent standard of living can be maintained for the residents of the RFGD, and at the same time preserve the water quality of their rivers, as an investment for their present and future. It was possible to establish criteria for environmental management focused on conserving the quality of surface water in the sub-basin of the Rincón River, to be replicated within the Golfo Dulce Forest Reserve in the Osa Peninsula.

En el presente trabajo se evaluó la calidad del agua de una fuente natural tratada con desinfectantes, la cual se usó en la crianza de pollos broiler en el trópico de la región San Martin; para este trabajo se usó un diseño completamente al azar (DCA), con tres tratamientos: Agua natural tratada con hipoclorito de sodio a dosis recomendada por el fabricante de 10ppm (testigo T0), Agua natural tratada con hipoclorito de calcio a dosis de 5ppm (T1) y Agua natural tratada con un desinfectante potabilizador biodegradable Biosanit – W, 500 ml/1000L de agua (T2), con 3 repeticiones por tratamiento, se evaluaron los siguientes parámetros: ganancia de peso, conversión alimenticia, mortalidad, consumo de agua y los parámetros Físico-Químicos y Microbiológicos del agua natural y del agua tratada con los tres desinfectantes, en la etapa de crecimiento-acabado (22 – 42 días). Con los tratamientos T1 y el tratamiento T2, se obtuvo una mejor ganancia de peso de pollos boiler respecto al tratamiento testigo T0. Con el tratamiento T1 se obtuvo la conversión alimenticia con 2,32 superando estadísticamente a los tratamientos T2 y T0, con quienes se obtuvieron promedios de 2,42 y 2,73 de C.A respectivamente. El consumo de agua no detectó diferencias significativas entre los tratamientos T0, T2 y T1 con promedios de 9027,7 ml, 8941,03 ml y 8699,05 ml de agua consumida respectivamente. Con el tratamiento T0 se obtuvo buenos resultados en los análisis microbiológicos, pero afecto los parámetros productivos de los pollos. Concluyendo que el uso de cloro en el agua de bebida a 5 ppm mejora las características microbiológicas y físico – químicas e influye positivamente en el comportamiento productivos de pollos broiler. | The following work evaluated water of natural source quality, treated with disinfectants, which was used in the raising of meat chickens in the tropics of the San Martin region; For this work, a completely randomized design (DCA) was used, with three treatments: Natural water treated with sodium hypochlorite at a dosage recommended by the manufacturer 0.25mL / liter of water or 10ppm (control T0), Natural water treated with hypochlorite from calcium 70% at a dose of 5ppm (T1) Natural water treated with a biodegradable water treatment disinfectant Biosanit - W, 500 ml / 1000L of water (T2), with 3 treatments and 3 repetitions per treatment, the following parameters were evaluated: weight gain, food conversion, mortality, water consumption and the Physical-Chemical and Microbiological parameters of the natural water and the water treated with the three disinfectants, in the stage of Growth-Finishing (22 - 42 days). With the T1 treatments and the T2 treatment, a better weight gain was obtained in the finished growth stage of boiler chickens with respect to the control treatment T0. With the T1 treatment, the best average value of feed conversion was obtained with 2.32 statistically overcoming the T2 and T0 treatments, with which averages of 2.42 and 2.73 of C.A were obtained, respectively. The water consumption did not detect significant differences between averages, where with the treatments T0, T2 and T1 obtained averages of 9027.7 ml, 8941.03 ml and 8699.05 ml of water consumed respectively. With the T0 treatment, good results were obtained in the microbiological analyzes, but it affected the productive parameters of the chickens. Concluding that the use of chlorine in drinking water at 5 ppm improves the microbiological and physico - chemical characteristics and positively influences the productive behavior of broiler chickens.

ilustraciones, gráficos, tablas | Mediante esta investigación se plantea evaluar el uso de coagulante químicos para remover el Color presente en el efluente del tratamiento secundario de la planta de tratamiento de agua residual del municipio de Tuluá Valle del Cauca, y posteriormente evaluar la relación beneficio/costos de su aplicación como alternativa para reducir la coloración del efluente. Esta idea surge gracias a la investigación y profundización en la problemática ambiental y de salud pública asociada a la degradación de ecosistemas y alteración paisajista que trae el generar un vertimiento con alto grado de coloración. En el presente proyecto se evidencian las actividades realizadas mediante ensayos de pruebas de jarras para hallar la dosis óptima de los coagulantes estudiados: Cloruro Férrico, Sulfato de Aluminio, Policloruro de Aluminio e Hidroxicloruro de Aluminio; a dichos ensayos se les determinó parámetros iniciales y finales de Color Aparente, Color Verdadero, pH y Temperatura; tras la identificación de la dosis óptima de cada coagulante se replicó el ensayo y se le analizó nuevamente los parámetros antes mencionados junto con Alcalinidad, Sólidos Sedimentables y DQO tanto iniciales como finales. Posteriormente se tabulan los resultados recopilados durante los ensayos, calculando el porcentaje de remoción alcanzado en Coloración verdadera. Debido a que la normatividad vigente en Colombia no establece un valor límite máximo para la remoción del parámetro objeto de estudio, nace a consideración de los investigadores establecer un porcentaje mínimo de remoción aceptable, el cual fue del 60% en remoción de Color Verdadero, con lo que se logró tener datos de mayor aceptabilidad y confiabilidad que pueden contribuir en el desarrollo de próximos proyectos relacionados con este tema. Cabe destacar que el objetivo de esta investigación se aborda con la finalidad de determinar la posible aplicación de coagulantes químicos como tratamiento terciario o de pulimiento en el tratamiento Convencional con que cuenta la PTAR municipal, de tal forma que favorezcan la minimización de problemáticas socioambientales que se puedan presentar en un futuro no muy lejano. | GLOSARIO / INTRODUCCIÓN / 1. DESCRIPCIÓN DEL PROBLEMA / 2. JUSTIFICACIÓN / 3. OBJETIVOS / 3.1 OBJETIVO GENERAL / 3.2 OBJETIVOS ESPECÍFICOS / 4. MARCO REFERENCIAL / 4.1 MARCO TEORICO / 4.1.1 Conceptos Básicos / 4.1.2 Sistema de Tratamiento de Aguas Residuales / 4.1.3 Tratamiento Secundario (Biológico) de las Aguas Residuales / 4.1.4 Filtros Percoladores / 4.1.5 Proceso general de Coagulación-Floculación / 4.1.6 Teoría de la Coagulación / 4.1.6.1 Factores que influyen en la Coagulación / 4.1.6.2 pH óptimos de Coagulación / 4.1.6.3 Principales Coagulantes Metálicos / 4.2 MARCO NORMATIVO / 4.3 ESTADO DEL ARTE / 4.4 MARCO CONCEPTUAL / 5. METODOLOGÍA / 5.1 IDENTIFICACIÓN DE COAGULANTES QUIMICOS QUE PUEDEN SER EMPLEADOS PARA LA REMOCIÓN DEL COLOR / 5.2 DETERMINACIÓN DE LA EFICIENCIA DE CADA COAGULANTE QUIMICO IDENTIFICADO PARA LA REMOCIÓN DEL COLOR MEDIANTE ENSAYOS DE LABORATORIO / 5.2.1 Manejo estadístico de datos / 5.3 EVALUACION Y PROPUESTA DEL USO DE LOS COAGULANTES QUÍMICOS CON BASE EN LA EFICIENCIA DE REMOCIÓN, ALTERACIÓN EN LA COMPOSICIÓN DEL AGUA RESIDUAL TRATADA Y LA RELACIÓN BENEFICIO/COSTO / 5.3.1 Matriz de priorización / 5.3.1.1 Valoración para él % de remoción de Color / 5.3.1.2 Relación Beneficio/Costo / 5.3.1.2.1 Cálculo de los beneficios / 5.3.1.2.2 Cálculo de los costos / 5.3.1.2.3 Cálculo de la relación Beneficio/Costo (B/C) / 5.3.1.3 Valoración para la afectación de otros parámetros estudiados (pH y Sólidos sedimentables) / 5.3.1.4 Valoración para la mejora de otros parámetros estudiados (DQO) / 6. RESULTADOS Y DISCUSIONES / 6.1 Identificación de los coagulantes químicos a utilizar en el estudio del proyecto / 6.2 DETERMINACIÓN DE LA EFICIENCIA DE CADA COAGULANTE QUÍMICO MEDIANTE ENSAYOS DE PRUEBA DE JARRAS EN LABORATORIO / 6.3 Ejecución de Prueba de Jarras / 6.3.1 Estudio práctico (Pruebas de Jarras) / 6.3.1.1 Primera Etapa del estudio práctico (Pruebas de Jarras) / 6.3.1.1.1 Diligenciamiento en Excel de los datos obtenidos tras realizar análisis de Prueba de Jarras / 6.3.1.1.2 Evaluación del comportamiento del coagulante respecto a la dosis aplicada vs el Color verdadero / 6.3.1.2 Segunda Etapa estudio práctico (Pruebas de Jarras) / 6.3.1.2.1 Diligenciamiento y Graficas en Excel de los datos obtenidos tras realizar replica de Prueba de Jarras / 6.4 EVALUACIÓN Y PROPUESTA DEL USO DE LOS COAGULANTES CON BASE EN LA EFICIENCIA DE REMOCIÓN, LA ALTERACIÓN EN LA COMPOSICIÓN DEL AGUA RESIDUAL TRATADA Y LA RELACIÓN BENEFICIO/COSTO / 6.4.1 Cálculo relación beneficio/costo / 6.4.1.1 Cálculo de los beneficios / 6.4.1.2 Cálculo de los costos / 6.4.1.2 Cálculo Relación Beneficio/Costo / 6.4.2 Matriz de priorización / CONCLUSIONES / RECOMENDACIONES / REFERENCIAS / ANEXOS /