Diatoms constitute a useful tool to evaluate the trophic status of aquatic systems, as they answer quickly to environmental changes. They have been used in water quality researches since the beginning of the 20th century, but only few reports are available from Argentina. In the present paper, several biological descriptors have been employed to evaluate the water quality of the influent and effluent streams from Los Padres Lagoon (Los Padres and La Tapera creeks, respectively), including Descy Index (DI) and Pampean Diatoms Index (PDI). In each creek, ten stems of the «giant bulrush» (Schoenoplectus californicus) were randomly collected and the main physical and chemical parameters were recorded in situ. In the laboratory, periphyton was removed and algae taxa were identified and counted. A total of 107 periphytic taxa were identified (83 at the inflow and 101 at the outflow). Diatoms constituted the richest and the most abundant group in both creeks. DI and PDI indices showed a higher eutrophic level in the influent, possibly due to the input of an important quantity of agricultural polluents of the surrounding lands and to the strong impact of birds. Species composition, diversity and equitability were the only biological descriptors suitable to assess the water quality in the present study. | Facultad de Ciencias Naturales y Museo

Con el objetivo de desarrollar técnicas para instalaciones solares que promuevan la eficiencia energética y la incorporación de energías renovables en edificios, este trabajo presenta el desarrollo de un pliego de especificaciones técnicas. Este aporte permite realizar un análisis previo del sistema y especificar sus componentes. Su utilización permite transparencia en las etapas de cotización y materialización, generando un estándar para los distintos oferentes y una vital herramienta de control para la dirección de obra. Su incorporación facilita la especificación de instalaciones y su integración en obras de arquitectura por la parte de profesiones. Posteriormente, el pliego fue aplicado a una instalación solar doméstica de agua caliente de uso sanitario, demostrando su aptitud y factibilidad. Los contenidos del pliego pueden aportar al mejoramiento y actualización de normativas para instalaciones solares y contribuir a la difusión e implementación de las energías renovables en edificios. | With the aim of developing solutions for solar water heating systems that promote energy efficiency and the incorporation of renewable energy in buildings, this paper presents the development of a technical specification for these systems. This contribution allows the analysis of solar systems at the design stage and the specification of the different components. It’s application will encourage transparency in the stages of requesting estimates and undertaking installations, providing a standard for the different installers offering quotations, and a vital tool for the supervision of the project. It’s inclusion will also aid the installation’s specification and their integration in architectural projects by professionals. This has allowed the application of the technical specification in a large domestic solar water heating installation, demonstrating its feasibility and ease of application. The contents of the specification also aims to contribute to further improvement and up-dating of standards for solar installations and promote the application of renewable energies in buildings. | Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES)

Tesis (M. Sc) -- CATIE, Turrialba (Costa Rica),2008 | En este estudio se analizó la situación del manejo y gestión de la zonas de recarga hídrica, principalmente de fuentes de agua para consumo humano, en Honduras y se propusieron lineamientos y criterios que apoyen a los decisores al nivel nacional, al nivel de los municipios y de las organizaciones e instituciones que tienen relación o responsabilidad directa con este tema. El análisis de los lineamientos de políticas, estrategias y acciones se realizó a partir de la recopilación de información primaria y secundaria, incluyendo la aplicación de entrevistas a actores claves de programas, proyectos e instituciones que tienen relación con el manejo y gestión de los recursos hídricos en Honduras, de la aplicación de entrevistas a actores claves de proyectos locales o comunitarios de agua para consumo humano seleccionados como estudios de caso, así como del análisis del marco legal e institucional. Le corresponde a las instituciones rectoras de los recursos, agua, bosque y suelo, principalmente al Instituto Nacional de Conservación y Desarrollo Forestal, Ã reas protegidas y Vida Silvestre y la Secretaría de Recursos Naturales y Ambiente, liderar los procesos necesarios y poner en agenda prioritaria la toma de decisiones para internalizar y viabilizar acciones concretas para enfrentar esta problemática de manera integral. In this study, the current situation related to the handling and management of hydric recharge zones was analyzed, mainly, in terMON of the use of water sources for human consumption in Honduras. Guidelines and criteria, supporting decision makers at national and municipal levels and the organizations and institutions, which have direct relation or direct responsibility with this subject were proposed. The analysis of policy guidelines , strategies and actions was made based on the compilation of primary and secondary information, including the application of interviews to key actors related to prograMON, projects and institutions showing relation with the handling and management of hydric resources in Honduras. Also, the application of interviews to key actors involved in local or community projects related to water for human consumption selected as case studies, as well as the analysis of the legal and institutional frame. It corresponds to the governing institutions in charge of the water, forest and soil resources, mainly, the National Institute of Forest Conservation and Development, Protected Areas and Wildlife (ICF) and the Secretary of Natural Resources and Environment (SERNA), to direct the necessary processes and prioritize in their agendas the decision making to internalize and facilitate concrete actions to face this problem integrally.

The objectives were to evaluate the effect of a waste of nondisperse water-based drilling fluid (WDF) on seed germination and vegetative traits in confectionary sunflower and to compare WDF with a chemical fertilizer (CF) for the above characters. Two soil types were used: savanna (sand lime texture) and vega (lime clay texture). Soils were put in aluminum trays where cowpea cv. Tejero Criollo was sowed. Fertilization treatment were: a) without fertilizer; b) CF equivalent to 300 kg 15-15-15/ha and c) WDF equivalent to dosage of treatment b. A split-plot design was used with four replications, the two soil types were main plots and the three fertilization treatments were subplots. The Least Significant Difference Test was used and the probability level was 0.05. The WDF was characterized chemically to approximate it to CF used; WDF did not have heavy metals. There were not significant differences for germination at 3 days after sowing (DAS), neither for seedling height at 8, 12 and 36 DAS, leaves/plant, stem diameter, root length, fresh and dry weight of shoot and root and root volume, while at 4, 8, 12 and 16 DAS the was a bigger seed germination in the Vega soil. Also, the germination was faster in the latter. The savanna soil yielded taller plants at 20 and 28 DAS. These results indicated that WDF did not cause a detrimental effect on sunflower seedling and the three fertilizer treatments had a similar performance for all traits evaluated. | Los objetivos fueron evaluar el efecto del desecho de un fluido de perforación (DFP) base agua no disperso sobre la germinación de semillas y caracteres vegetativos en el cultivo de girasol tipo confitero y comparar este DFP con un fertilizante químico (FQ) para los caracteres anteriores. Se utilizaron dos tipos de suelos: sabana (textura arenofrancosa) y vega (textura francoarcillosa). Los tratamientos de fertilización consistieron en: a) Sin fertilizante; b) FQ equivalente a 300 kg de 15-15-15/ha y c) DFP base agua no disperso equivalente a la dosis del tratamiento b. Se utilizó un diseño de parcelas divididas con cuatro repeticiones, las parcelas principales estuvieron constituidas por los dos tipos de suelos y las subparcelas por los tres tratamientos de fertilización. No se encontraron diferencias significativas para los caracteres: germinación a los 3 días después de la siembra (DDS), altura de plántulas a los 8, 12 y 36 DDS, número de hojas, diámetro del tallo, longitud de raíces, peso fresco y seco de vástago y de raíces y volumen radical, mientras que a los 4, 8, 12 y 24, hubo mayor germinación en el suelo de vega. También la germinación fue más rápida en este último. El suelo de sabana produjo plantas más altas a los 20 y 28 DDS. Estos resultados indican que el DFP base agua no disperso no causó un efecto detrimental a las plántulas de girasol y que los tres tratamientos de fertilización se comportaron de manera similar para todos los caracteres evaluados.

Objetivando-se estudar os efeitos de cinco níveis de condutividade elétrica da água de irrigação (CEa: 0,7; 2,7; 4,7; 6,7 e 8,7 dS m-1, a 25 oC), sobre a germinação, vigor e crescimento inicial de três cultivares (Nordestina, Paraguaçu CSRN-367) de mamona (Ricinus communis L.), conduziu-se um experimento, no delineamento inteiramente casualizado com 3 repetições, em esquema fatorial 5x3. As variáveis avaliadas foram percentagem de germinação, número de dias para germinar, índice de velocidade de emergência, altura de plantas e numero de folhas aos 20 dias após semeadura. Não houve efeito interativo dos fatores, apenas para altura de planta e numero de folhas. A percentagem de germinação decresceu com o aumento da salinidade, com decréscimos relativos para as variedades Nordestina, Paraguaçu e CSRN-367 de 3,92, 7.79 e 2,76% por incremento unitário de CEa, respectivamente, o número de dias para germinar e o índice de velocidade de emergência sofreram efeito significativo com os níveis de CEa testados e a altura de plantas e numero de folhas decrescem de forma linear com o incremento da CEa acima de 0,7 dS m-1.

With the objective to study the effects of five levels of electrical conductivity of the irrigation water (ECw: 0.7; 2.7; 4.7; 6.7 and 8.7 dS m-1, at 25 oC), on the initial growth and development of three cultivars (Nordestina, Paraguaçu e CSRN-367) of castor bean (Ricinus communis L.), an experiment was conducted (5X3 factorial), in a randomized design with 3 repetitions. The appraised variables were plant height, number of leavEs and stem diameter, twenty, forty and sixty days after seeding (DAS). There was no interactive effect of the factors, except for plant height and number of leaves. The plant height decreased with the increase of salinity, the relative decrease at 20, 40 and 60 DAS being, respectively of 8.68, 9.70 and 9.77% for unitary increment of Ecw. The number of leaves showed significant effect for the levels of ECw and the stem diameter decreased linearly with the increment of ECw above 0.7 dS m-1, the decrease being 7.63 and 7.91% for unitary increment of electrical conductivity of the irrigation water, 40 and 60 DAS, respectively.