Fil: Hämmerly, Rosana del Carmen. Universidad Nacional del Litoral. Facultad de Ingeniería y Ciencias Hídricas; Argentina. | Se propone mejorar las estimaciones de evapotranspiración a partir de la modelación que tiene en cuenta métodos de balance de agua y disponer de herramientas de cálculo eficientes y confiables que permitan una mejor determinación de disponibilidades y pérdidas de agua con fines hidrológicos y agronómicos. Para ello se plantea introducir el uso de métodos modernos de estimación de evapotranspiración, investigar la influencia que tienen sobre estos métodos la disposición y consistencia de datos de entrada y validar con datos de campo las estimaciones que se obtienen de los modelos. Para lograr los objetivos, se utilizaron el Modelo de Jaworski y el Modelo Balver, aplicados a parcelas experimentales situadas dentro del predio de la Estación Experimental Agropecuaria INTA Marcos Juárez en la provincia de Córdoba. A partir de las investigaciones realizadas se concluye la necesidad de incorporar un módulo de escurrimiento en el Modelo de Jaworski para subsanar la sobreestimación de la evapotranspiración y de humedad del suelo. Por su parte el Modelo Balver si bien requiere mayor información del sistema suelo-vegetación, analiza más detalladamente el recorrido del agua dentro del suelo y realiza un balance más elaborado De acuerdo a los resultados obtenidos, los Modelos de Jaworski y Balver se consideran aptos para su utilización, y de acuerdo a la información disponible se seleccionará el más conveniente de utilizar, decisión que también depende de los objetivos planteados y del grado de detalle que se requiera. | It intends to improve evapotranspiration estimates from the modeling that takes into account water balance methods and computational tools have efficient and reliable to allow a better determination of water availability and loss of hydrological and agricultural purposes. So, modern methods are used to estimate the evapotranspiration and the influence that the available information and their consistency have upon these methods are researched too. The results obtained have been validate with field data. To achieve the objectives, we used the Jaworski Model and the Balver Model applied to experimental parcels located within the premises of the Agricultural Experimental Station INTA Marcos Juárez in the province of Cordoba. From this research it is concluded about the need to incorporate in the Jaworski`s Model a runoff module to correct the overestimation of evapotranspiration and soil moisture. For its part, the Balver`s Model while requiring more information on the soil-vegetation system, discussed in more detail the flow of water into the soil and makes a more elaborate balance. According to the results, both models are considered suitable for use, and according to the information available will select the most convenient to use, a decision that also depends on the objectives and the degree of detail required.

O conhecimento das interações entre água superficial e água subterrânea devem ser exploradas no intuito de entender suas interligações, já que, a taxa de recarga e a qualidade da água subterrânea dependem fortemente dos mananciais de superfície. A zona hiporreica representa uma região de interação entre água superficial – água subterrânea, sendo um ambiente de grande dinâmica, onde ocorrem conjuntos de reações entre os componentes bióticos e abióticos nestes ecossistemas. O curso d’ água superficial forma apenas parte visível de um ecossistema de água doce, que inclui água subterrânea, aluviões e os sistemas ripários. A parte central desta zona de intercâmbio, denominada zona hiporreica, funciona como moduladora de ligações entre o fluxo de água superficial, água subterrânea, zona ripária e sistemas de aquíferos aluvionais. A dinâmica do movimento da água na zona hiporreica mostra a interação entre águas superficiais e subterrâneas, e sua dimensão indica a sua relativa magnitude de fluxo, onde ocorre trocas de massa entre rio e aquífero. As características ambientais que a zona hiporreica reúne, torna-se parte de um ambiente único, que agrupa características intrínsecas que faz desse ambiente tão dinâmico e de grande importância hidrológica, ecológica e geoquímica.

O presente experimento foi realizado com o objetivo de avaliar a influência da irrigação com água salina no crescimento e na produção de girassol (híbrido H251), além de monitorar a evolução de alguns atributos químicos do solo ao longo do ciclo da cultura. O delineamento experimental foi em blocos casualizados com seis tratamentos e cinco repetições. Os tratamentos consistiram de seis diferentes estratégias de irrigação, sendo cinco delas com utilização de água salina. As avaliações de crescimento (altura de planta, diâmetro de caule e número de folhas) foram realizadas aos 20; 40; 60; 80; 100 dias após semeadura (DAS). Aos 100 DAS foi realizada a colheita, ocasião em que se mediu o diâmetro de capítulo, sendo determinados posteriormente o peso de 1000 aquênios e a produtividade de aquênios. As coletas de solo foram realizadas concomitantemente às avaliações de crescimento, nas camadas 0-0,10; 0,10-0,30; 0,30-0,50 m. Os atributos químicos do solo avaliados foram Na+, CE e pH, além das relações Na+/Ca2+ e Na+/Mg2+. A cultura do girassol mostrou-se tolerante à salinidade da água de irrigação, indicando que ela pode ser irrigada com água de CE de até 3,53 dS m-1 durante todo o ciclo. Entretanto, quando se utilizar água de média ou alta CE, é necessária a adoção de práticas de controle da salinização/sodificação do solo. A tolerância do girassol à salinidade não dependeu da fase de desenvolvimento. Em geral, os atributos químicos do solo aumentaram e estabilizaram a partir da metade do ciclo.<br>This experiment was made to evaluate the influence of the irrigation with saline water on growth and production of sunflower (híbrido H251), besides monitoring the evolution of some chemical attributes of the soil along its cycle. The experimental design used was the randomized blocks with six treatments and five replications. The treatments consisted of six different irrigation strategies, five of them with use of saline water. The growth evaluations (plant height, stem diameter and leaf number) were made at 20; 40; 60; 80; 100 days after sowing (DAS). The harvest occurred at 100 DAS, then the capitulum diameter was measured and the weight of 1000 achenes, as well as its productivity, were determined. The soil samples were collected on the same dates of the growth evaluations at the layers of 0-0.10; 0.10-0.30; 0.30-0.50 m. The evaluated soil attributes were Na+, EC and pH, besides of the ratios Na+/Ca2+ and Na+/Mg2+. The sunflower appeared to be tolerant to the salinity of the irrigation water, what means it could be cultivated normally and still have a good production even when the water EC reaches up to 3.53 dS m-1. However, when using a medium/high EC water, it's needed to adopt some practices to control the salinization/sodification of the soil. The tolerance of the sunflower to salinity was not dependent of the development phase. Overall, the chemical attributes of the soil increased and stabilized from the middle of the cycle on.

Access to open water is considered good for the health and welfare of Pekin ducks. These studies investigated: 1.- the effect of water resource type (nipple drinker, narrow bell drinker, wide bell drinker, trough or pool) on duck health and behavior; 2.- the preference shown by ducks between pools of different depths (10cm, 20cm or 30cm) and whether the behaviours performed differed between these depths. Stage 1.- There was a significant effect of treatment on hygiene scores and nostril condition, with baths and troughs being better than the other resources. Overall, there was no effect of treatment on eye health score, gait or foot pad dermatitis. Significantly fewer ducks were resting inactive by the baths and troughs, and the % of ducks performing bathing behaviours was higher in those resources. Stage 2.- None of the factors analyzed had a significant effect on pool preference. Provision of open water seems to improve some aspects of duck health and welfare, and ducks were neither more attracted to, nor more averse to, deeper water. However, further work is needed to investigate open water resources such as pools or troughs at a commercial scale.

In desalination process, besides the potable water, highly salty and pollutant water (brine) is generated, which can be used for producing crops since it is carefully monitored. In order to test this hypothesis, bell pepper plants, cv. 'Margarita', were grown in coconut fiber substrate under greenhouse and were irrigated with nutrient solutions prepared with tap water, brine from desalination plant, and its dilution with tap water at 75, 50 and 25%, giving a range of electrical conductivities of the nutrient solution (ECs) of 2.6, 3.1, 6.6, 10.0 and 12.2 dS m-1 after the dilutions and fertilizers addition. Completely randomized blocks design was used with 5 treatments (salinity levels of the nutrient solutions) and six replications. Leaf area, number of marketable fruit, total and marketable yield were reduced with ECs increase. The marketable yield of bell pepper 'Margarita' reduced 6.3% for each unitary increase of ECs above 2.6 dS m-1 (threshold salinity) and the results suggest that in hydroponic system, the reduction of marketable yield with increasing ECs is promoted by reduction of the number of fruits per plant instead of a reduction of fruit mean weight.

RESUMEN: Se monitoreo la calidad del agua utilizando como indicador los coliformes fecales y totales en la bahía de Santa Marta. El grado de contaminación fue determinado mediante el análisis de datos de calidad del agua en nueve estaciones de muestreo. Cuatro de ellas en las playas de Santa Marta, Taganga, Playa Grande y el Rodadero; dos en las desembocaduras de los ríos Manzanares y Gaira y las tres restantes en la descarga del emisario submarino a diferentes profundidades (Fondo, Profundidad media y Superfi cie). Las muestras fueron tomadas entre enero de 2006 y diciembre de 2008 cada dos meses. Se encontró una asociación entre el vertimiento del emisario submarino cuyo caudal fue estimado en 1028,64±163,9 (L/s) y la calidad del agua en Taganga y Santa Marta. Se examinó el grado de contaminación en las estaciones de muestreo, encontrando niveles de contaminación media en la playa de Santa Marta, las desembocaduras de los ríos y la estación en la superfi cie del emisario submarino. | ABSTARCT: Water quality in Santa Marta bay was monitored using fecal and total coliforms. The pollution degree was determined by water quality data analyzing at nine sampling stations. Four of them on the beaches (Santa Marta, Taganga, Playa Grande and Rodadero), two at the mouths of Manzanares and Gaira rivers and the last in the submarine outfall discharges in different depths (Bottom, medium depth and surface). Samples were collected between January 2006 and December 2008, every two months. An association between the submarine outfall discharges (the fl ow was estimated at 1028.64 ± 163.9 L/s) and the water quality in Taganga and Santa Marta was found. The pollution degree at the sampling stations was examined, the Santa Marta beach, the mouths of the rivers and the submarine outfall surface station showed pollution at medium level.

In desalination process, besides the potable water, highly salty and pollutant water (brine) is generated, which can be used for producing crops since it is carefully monitored. In order to test this hypothesis, bell pepper plants, cv. 'Margarita', were grown in coconut fiber substrate under greenhouse and were irrigated with nutrient solutions prepared with tap water, brine from desalination plant, and its dilution with tap water at 75, 50 and 25%, giving a range of electrical conductivities of the nutrient solution (ECs) of 2.6, 3.1, 6.6, 10.0 and 12.2 dS m-1 after the dilutions and fertilizers addition. Completely randomized blocks design was used with 5 treatments (salinity levels of the nutrient solutions) and six replications. Leaf area, number of marketable fruit, total and marketable yield were reduced with ECs increase. The marketable yield of bell pepper 'Margarita' reduced 6.3% for each unitary increase of ECs above 2.6 dS m-1 (threshold salinity) and the results suggest that in hydroponic system, the reduction of marketable yield with increasing ECs is promoted by reduction of the number of fruits per plant instead of a reduction of fruit mean weight.

The aim of this study was to evaluate the fungal microflora present in drinking water and domestic sewage from different districts of Santa Maria, Rio Grande do Sul, Brazil. Water and sewage samples were collected during the four seasons and analyzed by the technique of Colony Forming Units (CFU). Yeasts and fungi of the genera Penicillium and Aspergillus were observed in the water samples. The genus Geotrichum was also found in the sewage. Therefore, it is concluded that treatment of water held in the municipality is unable to remove these agents.<p><p> objetivo deste estudo foi investigar a microbiota fúngica presente na água potável e no esgoto doméstico de distintos bairros de Santa Maria, Rio Grande do Sul, Brasil. Amostras de água e esgoto foram colhidas durante as quatro estações do ano e analisadas pela técnica de Unidades Formadoras de Colônias (UFC). Foi observada a presença dos gêneros Penicillium, Aspergillus e leveduras nas amostras de água. No esgoto, além dos agentes fúngicos reportados na água foi identificado o gênero Geotrichum. Dessa forma, conclui-se que o tratamento da água realizado no município não é capaz de eliminar estes agentes.