WorldWideScience

Sample records for ambiente estuarial rasgos

  1. Banco arenoso en un ambiente estuarial: rasgos de fondo y dinámica sedimentaria

    Directory of Open Access Journals (Sweden)

    Laura G. Vecchi

    2008-09-01

    Full Text Available Los bancos de arena son rasgos comunes en la boca de los canales de marea del estuario de Bahía Blanca (sur de la provincia de Buenos Aires. Este estudio tiene por objetivo incrementar el conocimiento sobre los procesos y mecanismos de formación y mantenimiento de los bancos estuariales. La investigación se centró en un banco elongado, de 4 km de largo, ubicado en la boca del canal La Lista, denominado banco La Lista. A través de datos acústicos (ecosonda y sonar lateral se determinaron rasgos morfológicos de fondo. Estos, conjuntamente con muestras de sedimento y mediciones de corrientes, posibilitaron definir la hidrodinámica y el transporte sedimentario. La arena movilizada desde el interior del canal La Lista por la corriente de bajante constituye la principal fuente de sedimento del banco. Sobre el flanco norte del banco, el transporte neto de arena como carga de fondo se produce hacia el sureste debido a la corriente de reflujo. Aquí, el transporte de sedimento estimado fue de 0,02188 gr cm-1 seg-1. En oposición, en el flanco sur, la dominancia del flujo produce un transporte de 0,00451 gr cm-1 seg-1. Por lo tanto el mantenimiento del banco es el resultado de una asimetría de flujo/reflujo sobre sus flancos, generándose un transporte sedimentario residual en sentido horario. En consecuencia en los últimos años el banco ha experimentado cambios en la configuración de la cresta y crecido vertical y longitudinalmente.

  2. Banco arenoso en un ambiente estuarial: rasgos de fondo y dinámica sedimentaria Sandbanks in a tidal environment: Bottom features and sedimentary dynamics

    Directory of Open Access Journals (Sweden)

    Laura G. Vecchi

    2008-09-01

    Full Text Available Los bancos de arena son rasgos comunes en la boca de los canales de marea del estuario de Bahía Blanca (sur de la provincia de Buenos Aires. Este estudio tiene por objetivo incrementar el conocimiento sobre los procesos y mecanismos de formación y mantenimiento de los bancos estuariales. La investigación se centró en un banco elongado, de 4 km de largo, ubicado en la boca del canal La Lista, denominado banco La Lista. A través de datos acústicos (ecosonda y sonar lateral se determinaron rasgos morfológicos de fondo. Estos, conjuntamente con muestras de sedimento y mediciones de corrientes, posibilitaron definir la hidrodinámica y el transporte sedimentario. La arena movilizada desde el interior del canal La Lista por la corriente de bajante constituye la principal fuente de sedimento del banco. Sobre el flanco norte del banco, el transporte neto de arena como carga de fondo se produce hacia el sureste debido a la corriente de reflujo. Aquí, el transporte de sedimento estimado fue de 0,02188 gr cm-1 seg-1. En oposición, en el flanco sur, la dominancia del flujo produce un transporte de 0,00451 gr cm-1 seg-1. Por lo tanto el mantenimiento del banco es el resultado de una asimetría de flujo/reflujo sobre sus flancos, generándose un transporte sedimentario residual en sentido horario. En consecuencia en los últimos años el banco ha experimentado cambios en la configuración de la cresta y crecido vertical y longitudinalmente.Tidal sandbanks are sedimentary features com monly found at the inlets of the tidal channels of Bahía Blanca Estuary (south Buenos Aires Province. To improve our understanding of the processes and mechanisms responsible for the formation and maintenance of the tidal sandbanks in estuaries, we carry out this study. We focus in a tidal sandbank located at La Lista channel mouth, denominated La Lista bank. It has an elongate shape with 4 km long. Bathymetric surveys, side-scan sonar records, grain

  3. rasgos funcionales

    Directory of Open Access Journals (Sweden)

    J.P. González-Varo

    2015-01-01

    Full Text Available Muchas especies de mamíferos carnívoros (Orden Carnivora consumen frutos carnosos, transportan semillas en sus tractos digestivos y las defecansin dañarlas en condiciones apropiadas para la germinación. En este artículo, revisamos el conocimiento adquirido sobre este mutualismo en lasúltimas tres décadas, desde que tres trabajos pioneros revelaron la importancia de los carnívoros como dispersores de semillas en ecosistemastemplados. Nos centramos en los rasgos funcionales de los carnívoros consumiendo frutos y diseminando semillas, haciendo especial énfasis ensus diferencias con las aves, el principal grupo de vertebrados frugívoros en ecosistemas templados. Los carnívoros no están sujetos a las restriccionesfenológicas o morfológicas que típicamente limitan el consumo de determinados frutos en muchas especies de aves. Consumen preferentementefrutos cuyos atributos son compartidos con muchas especies de frutos cultivados por el hombre, lo que explica el consumo frecuente deéstos en paisajes antrópicos. Sus amplios requerimientos espaciales favorecen la dispersión de semillas a larga distancia, mientras que su generalismoen relación al hábitat favorece el flujo de semillas entre hábitats contrastados. De este modo, los carnívoros promueven la conectividadentre poblaciones vegetales y la colonización. Estas funciones ecológicas son clave para las comunidades vegetales nativas, especialmente en escenariosde cambios de uso de suelo. Sin embargo, estos patrones de dispersión de semillas pueden contribuir a la invasión de plantas exóticas.Aún ignoramos en gran medida el papel de los carnívoros en términos cuantitativos de la dispersión de semillas y las diferencias funcionales entreespecies dentro del gremio. La integración de muestreos clásicos e innovadoras técnicas moleculares y de análisis espacial promete aportar conocimientoinédito en estas cuestiones.

  4. Rasgos postmodernos de la educación ambiental. Una formación pertinente con las nuevas corrientes de pensamiento

    Directory of Open Access Journals (Sweden)

    Francisco Javier Perez Rodriguez

    2015-02-01

    Full Text Available Los problemas ambientales que se suscitan a escala global son evidencia de una crisis, la cual es expresión de una coyuntura más profunda que trastoca los fundamentos del pensamiento de la humanidad en toda una era. Esta situación tiene sus causas primigenias en el modo general de conocer que desde el Renacimiento se implantó en gran parte del mundo occidental y que erigió al desarrollo y al progreso como idearios, hecho que finalmente se tradujo en una relación insostenible entre los humanos y la naturaleza. Esto expone la necesidad que desde las canteras de la educación se dé apertura a una formación ambiental cónsona con las nuevas corrientes de pensamiento. Es por ello que este ensayo pretende esgrimir los rasgos postmodernos de la Educación Ambiental como proceso pedagógico formal y no escolarizado en los planos epistemológicos, ontológicos y axiológicos, estableciendo la pertinencia del estudio de los problemas ambientales a partir de la crítica a los logos de la ciencia clásica, dando a su vez apertura a la concatenación de ideas y tópicos para la generación de un pensamiento complejo, un conocimiento interdisciplinario y saberes con grandes cimientos éticos que garanticen el cumplimiento de los propósitos de la Educación Ambiental.

  5. RASGOS DE PERSONALIDAD EN PACIENTES CON OBESIDAD

    Directory of Open Access Journals (Sweden)

    Alejandra Bravo Del Toro

    2011-01-01

    Full Text Available El presente estudio analizó los rasgos de personalidad con mayor incidencia en una población mexicana con obesidad. Se distinguieron los rasgos que intervienen en el funcionamiento diario de los sujetos. La muestra estuvo conformada por 60 pacientes: 31 hombres y 29 mujeres, con edades de 30 a 40 años, casados, con nivel educativo básico y que acudían a consulta médica en un centro de diagnóstico clínico, con antecedentes de obesidad. Se utilizó el perfil-inventario de la personalidad de Gordon, según el cual se comprobó que los pacientes con obesidad tienden a mostrar rasgos de personalidad por debajo de la norma. Los análisis demostraron relaciones significativas entre la gente obesa y cada uno de los rasgos de personalidad con menor prevalencia que mide la escala.

  6. ambiental

    Directory of Open Access Journals (Sweden)

    Roque Leal Salcedo

    2008-01-01

    Full Text Available El derecho internacional ambiental es un conocimiento de carácter transversal, que entre otras consideraciones refleja las preocupaciones de la sociedad por la implementación de un modelo de desarrollo sustentable para el respeto a las reglas del medio natural que garantizan la integridad y renovación de los sistemas naturales. El presente artículo enfoca esta visión a través del análisis de material documental revisado, entre ellos tratados internacionales que permiten distinguir el desarrollo del derecho internacional ambiental y el papel de Organización de las Naciones Unidas (ONU, en el propósito común del derecho individual y colectivo de disfrutar de una vida, un ambiente seguro, sano y ecológicamente equilibrado. En función a estas disertaciones las consideraciones finales exponen parte de la visión que ha estructurado la ONU y que representan un aporte considerable en el fomento de la conciencia mundial sobre la necesidad de establecer vínculos entre las naciones para el continuo desarrollo de esta rama del derecho.

  7. Cuerpo y subjetividad: rasgos, configuraciones y proyecciones

    OpenAIRE

    Cachorro, Gabriel

    2008-01-01

    El cuerpo y la subjetividad constituyen dos conceptos relevantes en las ciencias sociales. Solos o agrupados han sido objetos de estudios de diversas disciplinas, abordados con tratamientos de lo más diversos. Su riqueza es inagotable y admite infinitas miradas. Este texto aborda estas categorías teóricas, proponiendo tres secciones diferenciadas. La primera dibuja los rasgos de las dos categorías teóricas, las describe identificando sus estructuras, límites, propiedades, cruce...

  8. Ambient degradation, irregular occupation and sustainable handling in complex estuary-lagoon Mundaú/Manguaba, Alagoas State (AL

    Directory of Open Access Journals (Sweden)

    Francisco de Assis Salviano de Sousa

    2008-12-01

    Full Text Available The evaluation of environmental impacts constitutes an instrument of the environment politics capable to assure the accomplishment of a systematic examination of the risks decurrent of one determined human action, as well as of its alternatives. This work had as objective to disclose to the public and responsible for the decision taking the raised results at Complex Estuary-Lagoon Mundaú/Mangaba (CELMM, at State of Alagoas, Brazil, with emphasis in the possible consequences that the related degrading action can generate. The main detected impacts resultant of degradings actions had been: deposition of sediments, to block of the lagoon, antropization of the landscape, water’s pollution, deforestation, erosion and reduction of biodiversity. As forms to brighten up these impacts had been suggested: drainage, accompany of the water’s quality, cultivation of native bush species, insert of native species, urban and tourist planning, projects of environmental education, displacement of industries, plantations and constructions and control of the real estate speculation.

  9. Distimia: estudio descriptivo y rasgos de personalidad.

    Directory of Open Access Journals (Sweden)

    Sergio Ocio León

    1994-01-01

    Full Text Available Se exponen los resultados de una investigación sobre una muestra de pacientes distímicos, diagnosticados siguiendo criterios CIE-10, Ya los que se realizó la sección E (Depresión de la CIDI Medular (primera versión autorizada de la Entrevista Diagnóstica Compuesta. Los datos en que se ha centrado el estudio son: sociodemografía, antecedentes de trastorno psiquiátrico, características clínicas y rasgos de personalidad (según el cuestionario de personalidad 16-PF. Los resultados nos acercaron al conocimiento del trastorno distímico, así como al manejo de la CIE-10. Destaca el carácter objetivamente moderado de la sintomatología distímica, su frecuente asociación a lo largo de la evolución con otro trastorno depresivo, y la existencia de unos rasgos de personalidad predominantes en este tipo de pacientes

  10. Matutinidad-vespertinidad y ansiedad rasgo en adolescentes

    Directory of Open Access Journals (Sweden)

    Mª. José Collado-Mateo

    2013-01-01

    Full Text Available El objetivo de este trabajo fue estudiar la relación entre la matutinidad-vespertinidad y la ansiedad rasgo en adolescentes. La muestra estaba formada por 638 adolescentes de 12 a 14 años. Se midió la matutinidad-vespertinidad mediante la Escala de Matutinidad-Vespertinidad para Niños, MESC (Carskadon, Vieira y Acebo, 1993 y la ansiedad rasgo mediante el Inventario de Ansiedad Estado-Rasgo para niños, STAIC (Spielberger, Edwards, Lushene, Montuori y Platzek, 1973; Spielberger, Edwards y Lushene, 1990. Los resultados indicaron que las chicas eran más vespertinas, que la vespertinidad aumentaba con la edad y una relación negativa entre matutinidad y ansiedad rasgo. Aquellos adolescentes más vespertinos obtuvieron una mayor ansiedad rasgo, posiblemente debido a un mayor desajuste entre los ritmos biológicos y sociales (horarios escolares matutinos.

  11. Estuary regime

    International Nuclear Information System (INIS)

    The primary aim of this research into estuary regime is to provide engineers with an improved method of predicting the long term evolutionary effects of major engineering changes in estuaries. Of specific interest to the Department of Trade and Industry's renewable energy R and D programme is the long term impact of tidal energy barrages on estuarine morphology. It is considered that the approach being taken is the most appropriate line to follow in terms of developing an applicable estuary regime predictive capability. As a consequence it is considered that any further regime model development should be complimentary to this approach. In addition to model development there is still an enormous amount of basic research required in examining sediment transport processes within the estuarine environment. Recently developed models for predicting the motion of fluidised mud on inter-tidal and sub-tidal banks, an important process within the estuarine sediment regime, requires specific field data calibration and validation. The impacts of wave action on sediment mobility on estuarine banks is a further area requiring field measurements. It is recommended that the opportunity be taken to obtain a set of measurements at a site following construction of major engineering works to provide data for future verification of a regime model. Possibilities exist, for example, on the Tees Estuary for such measurements. (author)

  12. Algunos rasgos del lenguaje del niño ciego

    OpenAIRE

    Pérez Pereira, Miguel

    1991-01-01

    Se somete a crítica la denominada perspectiva tradicional sobre el desarrollo del lenguaje de los niños ciegos. Según ésta, los niños ciegos, debido a los efectos que sobre su desarrollo cognitivo tendrá la carencia de información visual, presentarán un retraso en su desarrollo lingüístico, así como ciertos rasgos de éste que lo hacen defectuoso. Los análisis efectuados, en que se compara una niña ciega de nacimiento con su hermana gemela con visión, indica...

  13. Estuary Classification Revisited

    OpenAIRE

    Guha, Anirban; Lawrence, Gregory A.

    2012-01-01

    This paper presents the governing equations of a tidally-averaged, width-averaged, rectangular estuary in completely nondimensionalized forms. Subsequently, we discover that the dynamics of an estuary is entirely controlled by only two variables: (i) the Estuarine Froude number, and (ii) a nondimensional number related to the Estuarine Aspect ratio and the Tidal Froude number. Motivated by this new observation, the problem of estuary classification is re-investigated. Our analysis shows that ...

  14. Prediction in Ungauged Estuaries

    OpenAIRE

    J. I. A. Gisen

    2015-01-01

    Estuaries have been used for settlement by humans since 5000-9000 years ago [Day et al., 2012]. The calm environment and nutrient-rich soil encouraged the development of ports and agriculture. Over-development however has put estuaries in unhealthy condition, where the water is polluted (excessive nutrient or salt intrusion problem) and natural morphodynamic equilibrium is disturbed. This implies that the need for effective estuarine management is crucial. Unfortunately, most of the estuaries...

  15. Relaciones entre ansiedad-rasgo y ansiedad-estado en competiciones deportivas

    OpenAIRE

    Francis RIES; Castañeda Vázquez, Carolina; Campos Mesa, María del Carmen; Castillo Andrés, Óscar del

    2012-01-01

    En esta investigación se pretende comprobar la teoría de la interacción de Spielberger (1972) en el ámbito de la competición deportiva, analizando las relaciones entre ansiedad-estado y ansiedad-rasgo en la competición, según las dimensiones somáticas y cognitivas de la ansiedad-rasgo y ansiedadestado. Para evaluar ambos constructos se utilizó la versión alemana de los cuestionarios WAI-T y WAI-S, en una muestra de 135 deportistas de Luxemburgo. Los resultados obtenidos seña...

  16. Computation of dilution discharge and mean concentration of effluents in Beypore Estuary, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    DineshKumar, P.K.; Josanto, V.; Sankaranarayanan, V.N.

    Tide dominated Beypore estuary along the west coast of India was studied to estimate the mean flow available for diluting the conservative effluents based on the distribution of ambient salinity as a guide through one dimensional analysis...

  17. Estuary Classification Revisited

    CERN Document Server

    Guha, Anirban

    2012-01-01

    The governing equations of a tidally averaged, width averaged, rectangular estuary has been investigated. It's theoretically shown that the dynamics of an estuary is entirely controlled by three parameters: (i) the Estuarine Froude number, (ii) the Tidal Froude number and (iii) the Estuarine Aspect ratio. The momentum, salinity and integral salt balance equations can be completely expressed in terms of these control variables. The estuary classification problem has also been reinvestigated. It's found that these three control variables can completely specify the estuary type. Comparison with real estuary data shows very good match. Additionally, we show that the well accepted leading order estuarine integral salt balance equation is inconsitent with the leading order salinity equation in an order of magnitude sense.

  18. El docente investigador: su génesis teórica y sus rasgos

    Directory of Open Access Journals (Sweden)

    Natalia Campos Saborío

    2003-01-01

    Full Text Available El propósito de este artículo es enunciar los rasgos que caracterizan al docente investigador. Para ello, me ubico en el contexto teórico, desde dónde conceptualizo sus calidades, a saber: visión de mundo, de paradigma curricular, y de investigación educativa

  19. Penobscot Estuary (Maine) Monitoring

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's NEFSC collects fisheries data from the Penobscot Estuary using several types of fishing gear. The data is used to determine species presence, relative...

  20. Bibliography on Alaska estuaries

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This bibliography was compiled to assist in working up “profiles” for the estuaries in Alaska. The purpose of the profiles is to list in a narrative form the...

  1. La influencia de los rasgos psicológicos en las actitudes hacia el empleo

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    Antonia Mercedes García Cabrera

    2008-01-01

    Full Text Available Esta investigación explica la influencia que el rasgo psicológico locus de control, conjuntamente con las variables que definen el capital humano de un país -género, edad y educación-, ejercen sobre las actitudes hacia el empleo en la República de Cabo Verde. De entre estos rasgos demográficos del individuo, el género es analizado más profundamente debido al interés actual por reducir las desigualdades en razón de género en el mercado laboral. Los 448 cuestionarios recabados muestran que, en este país, los atributos demográficos edad y nivel de estudios, así como el rasgo de personalidad locus de control, son importantes determinantes de las actitudes hacia el empleo de la población activa. Los resultados ofrecen las bases sobre las que redirigir las políticas de empleo en Cabo Verde para afrontar los puntos débiles que limitan el desarrollo del mercado de trabajo y amenazan la integración social.

  2. NEPmap (National Estuary Program Mapper)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The NEPmap is designed to provide information in context with National Estuary Program Study Areas. There are 28 National Estuary Programs (NEPs) in the U.S.that...

  3. Evaluación del rasgo textura en tubérculos de Solanum tuberosum grupo Phureja y búsqueda de genes candidatos asociados al rasgo

    OpenAIRE

    Guateque Alba, Magda Alejandra

    2014-01-01

    Solanum tuberosum, es una especie de la familia de las solanáceas. En Colombia, es un alimento básico tanto como consumo en fresco o procesado. Sin embargo, el rasgo de textura no se ha estudiado en profundidad en los tubérculos de papa colombianos. Por tal razón en esta investigación se realizó la fenotipificación precisa de este carácter complejo y se realizó un análisis de asociación genética con marcadores moleculares tipo SNPs, con el fin de acercarse a la comprensión gené...

  4. Especies leñosas nativas claves para la restauración ecológica del Embalse de Chisacá, Colombia, con base en rasgos importantes de su historia de vida

    Directory of Open Access Journals (Sweden)

    Rodríguez Ramírez Natalia

    2006-12-01

    Full Text Available Se determinaron cinco especies nativas leñosas, como claves para la restauración de plantaciones de Pinus patula
    y Corredor ripario potrerizado del embalse de Chisacá (localidad de Usme, Bogotá, Colombia 3.000-3.250
    msnm; 4°08’59’’ N; 74°17’62’’ W, con base en Rasgos de de Historia de Vida (RHV y otras características de
    especies presentes en estas áreas. Teniendo en cuenta el objetivo del estudio y las características de las áreas
    degradadas se seleccionaron y analizaron 23 rasgos a cada una de las especies evaluadas en los distintos ambientes. En la zona de pinos se estudiaron 23 especies, 21 en el corredor ripario potrerizado y 20 en el Matorral Bajo. Se estableció un sistema de calificación para las posibles respuestas de cada uno de los rasgos según su incidencia en la restauración ecológica de las áreas a restaurar. Posteriormente, se calificaron los resultados de los rasgos de cada una de las especies y se calculó una calificación final de éstas. Se recomiendan como especies claves para la restauración las cinco especies que obtuvieron mayor calificación final. Teniendo en cuenta lo anterior se recomiendan como especies claves para la restauración de la zona de pinos las especies Hesperomeles goudotiana (72,41%, Vallea stipularis (67,82%, Symplocos s theiformis (67,82%, Holodiscus argenteus (65,52%, y Myrcianthes leucoxyla (65,52% y para el corredor ripario potrerizado las especies Hesperomeles goudotiana (75,86%, Brugmansia sanguinea (74,71%, Myrcianthes leucoxyla (68,97%, Berberis goudotii (65,48% y Vallea stipularis (64,37%. La selección de especies claves para la restauración con base en RHV parece ser una metodología adecuada, siempre y cuando la selección de rasgos se haga cuidadosamente, teniendo en cuenta
    los objetivos del estudio y que las especies consideradas se estudien en cada ambiente donde se desarrollen. En
    efecto, se observó que los rasgos responden de

  5. RASGOS DEL TEMPERAMENTO DE LOS PERROS DOMÉSTICOS (CANIS FAMILIARIS: EVALUACIONES CONDUCTUALES

    Directory of Open Access Journals (Sweden)

    ADRIANA JAKOVCEVIC

    2009-08-01

    Full Text Available

    Los rasgos del temperamento se definen como tendencias conductuales estables entre situaciones similares y a lo largo del tiempo. En el presente trabajo se revisan las pruebas conductuales diseñadas para la evaluación de rasgos aislados del temperamento en los perros domésticos. Para cada dimensión se describen los estímulos empleados, las respuestas evaluadas y el correlato fisiológico de las mismas. Los rasgos más estudiados fueron la temerosidad, la agresividad y la sociabilidad. Sin embargo, sólo la primera cuenta con correlatos fisiológicos bien establecidos. Finalmente, las evaluaciones conductuales resultan de suma importancia para la selección de los perros para las distintas funciones que cumplen en la sociedad humana: detección de drogas, compañía, guardia, rescate de personas, etc.

  6. Relación entre rasgos desadaptativos de personalidad y farmacodependencia

    OpenAIRE

    Cynthia De Macedo Neuenschwander

    2006-01-01

    El presente estudio tuvo como propósito evaluar la relación entre los rasgos desadapta tivos de la personalidad y la dependencia de sustancias psicoactivas en una muestra de pacientes farmacodependientes. Los instrumentos utilizados fueron el Inventario Clínico Multiaxial de Millon-II y la ficha de datos personales. Se calculó la confiabilidad en nuestro medio (0.78). La muestra, no probabilísticaaccidental, estuvo conformada por 108 participantes dependientes de sustancias psicoactivas (alco...

  7. Personalidad, ansiedad estado-rasgo e ingreso a la universidad en alumnos preuniversitarios

    OpenAIRE

    Isabel Niño de Guzmán; Arturo Calderón; Marisa Escalante; Tula Lira; Roxanna Morote; Lourdes Ruda

    2000-01-01

    Estudio correlacional que identifica las dimensiones de personalidad, el tipo de ansiedad y las características sociodemográficas de alumnos de un centropreuniversitario. Se trabajó con 318 participantes de ambos sexos (43.8% mujeres y 56.2% hombres), que entre 16 y 19 años. Se los evaluó con los siguientes instrumentos: (a) NEO PI-R de Costa y McCrae (1992), (b) Inventario de Ansiedad Estado-Rasgo de Spielberger (IDARE, 1975) y (c) reporte de los tutores. Los resultados confirman la pre...

  8. Representaciones sociales de mujeres docentes de secundaria con respecto a rasgos femeninos en alumnos varones

    OpenAIRE

    Jorge Armando Revilla Fajardo; Carlos David Carrillo Trujillo

    2006-01-01

    La identidad de género tiene como referente las actividades escolares para su formación. Se realizaron entrevistas a profundidad con cuatro docentes mujeres de escuelas públicas de secundaria respecto de las actitudes de las docentes mujeres de este nivel hacia los rasgos femeninos en alumnos varones. Las actitudes de rechazo, discriminación, estigmatización y agresión de los pares y de intervención de parte de las docentes son una característica de la vida escolar de los ni...

  9. Explorando los rasgos de personalidad en adolescentes que manifiestan conductas problemáticas

    OpenAIRE

    Molina Martín, Susana; Inda Caro, Mª de las Mercedes; Fernández García, Carmen María

    2009-01-01

    El objetivo de esta investigación es doble. En primer lugar, estudiamos la adecuación de los datos al modelo de cinco factores, y, en segundo lugar, identificamos los rasgos de personalidad que manifiestan aquellos adolescentes que dicen tener ciertas problemáticas en su vida cotidiana. Para ello utilizamos dos instrumentos de evaluación: el Cuestionario de Personalidad para Adolescentes (16PF-APQ ) y el Cuestionario Autoaplicado de Síntomas que elaboramos a pa...

  10. Inteligencia emocional, rasgos de personalidad e inteligencia psicométrica en adolescentes

    OpenAIRE

    Mesa Jacobo, Jennifer Rose

    2015-01-01

    Esta investigación tiene como objetivo estudiar la relación entre IE de rasgo y personalidad en adolescentes. La muestra está compuesta por 805 alumnos, de entre 11 y 19 años, de República Dominicana y España por lo que se ha intentado identificar diferencias entre ambas muestras, además de profundizar en la validez predictiva de los constructos antes mencionados y el CI sobre el rendimiento académico (RA) en la muestra dominicana. También se han analizado las características psicométricas de...

  11. Detector automático de rasgos oculares mediante filtros de Gabor

    OpenAIRE

    Cachazo Maroco, Daniel

    2010-01-01

    Proyecto Fin de Carrera leído en la Universidad Rey Juan Carlos en el curso académico 2009/2010. Tutor del Proyecto: Ángel Serrano Sánchez de León En esta investigación biométrica se ha creado un detector automático de rasgos oculares capaz de localizar la ubicación de éstos en la imagen facial de una persona. Los puntos que hemos localizado son los extremos de los ojos y las pupilas. Para ello se van a emplear una serie de wavelets de Gabor, filtros bidimensionales pasabanda c...

  12. Nivel de pensamiento, rasgos de personalidad y promedios académicos en estudiantes universitarios

    Directory of Open Access Journals (Sweden)

    Elda Cerchiaro

    2013-10-01

    Full Text Available El presente artículo recoge los aspectos más destacados de la investigación desarrollada en el año 2004 en la Universidad del Magdalena, centrada en establecer la relación entre nivel de pensamiento, rasgos de personalidad y promedios académicos en estudiantes universitarios. Los resultados arrojados por este estudio nos permitieron aproximarnos a una caracterización de los estudiantes de la Universidad del Magdalena en relación con el nivel de pensamiento que poseen, asociado a unos rasgos o factores de personalidad que, de alguna forma, se relacionan con altos promedios académicos, llevándonos a establecer tendencias por programas académicos, fundamentales para construir estrategias de intervención cognitiva muy acordes con las necesidades detecta-das. Así mismo, estos hallazgos ofrecen una oportunidad para revisar el verdadero sentido del rendimiento académico como expresión de las competencias que el estudiante ha desarrollado a través de su proceso formativo. (Duazary; 2006: 80-88

  13. Ambient Space and Ambient Sensation

    DEFF Research Database (Denmark)

    Schmidt, Ulrik

    The ambient is the aesthetic production of the sensation of being surrounded. As a concept, 'ambient' is mostly used in relation to the music genre 'ambient music' and Brian Eno's idea of environmental background music. However, the production of ambient sensations must be regarded as a central...... aspect of the aesthetization of modern culture in general, from architecture, transport and urbanized lifeforms to film, sound art, installation art and digital environments. This presentation will discuss the key aspects of ambient aesthetization, including issues such as objectlessness...

  14. Ecology of estuaries

    International Nuclear Information System (INIS)

    Ecology of Estuaries: Anthropogenic Effects represents the most definitive and comprehensive source of reference information available on the human impact on estuarine ecosystems. The book discusses both acute and insidious pollution problems plaguing these coastal ecotones. It also provides a detailed examination of the deleterious and pervasive effects of human activities on biotic communities and sensitive habitat areas in estuaries. Specific areas covered include organic loading, oil pollution, polynuclear aromatic hydrocarbons, chlorinated hydrocarbons, heavy metals, dredging and dredge-spoil disposal, radionuclides, as well as other contaminants and processes. The diverse components of these anthropogenic influences are assembled in an organized framework and presented in a clear and concise style that will facilitate their understanding

  15. Rasgos de historia de vida de especies pioneras en la Reserva Natural Ibanasca (Ibagué, Tolima, Colombia)

    OpenAIRE

    Gómez Ruíz, Pilar Angélica; Vargas Ríos Jesús Orlando

    2006-01-01

    Los rasgos de historia de vida (RHV) son cualidades o atributos propios de cada individuo que representan
    respuestas en aspectos fisiológicos, morfológicos, anatómicos y ecológicos ante las condiciones ambientales
    presentes. En la Reserva Natural Ibanasca se seleccionaron 17 especies de plantas leñosas pioneras y en cada una se evaluaron 18 rasgos relacionados con las fases de dispersión, establecimiento y persistencia con el fin de establecer agrupaciones entre las espe...

  16. Det ambiente

    DEFF Research Database (Denmark)

    Schmidt, Ulrik

    Om begrebet "det ambiente", der beskriver, hvad der sker, når vi fornemmer baggrundsmusikkens diskrete beats, betragter udsigten gennem panoramavinduet eller tager 3D-brillerne på og læner os tilbage i biografsædet. Bogen analyserer, hvorfan ambiente oplevelser skabes, og hvilke konsekvenser det...

  17. Ambient Sensors

    OpenAIRE

    Börner, Dirk; Specht, Marcus

    2014-01-01

    This software sketches comprise two custom-built ambient sensors, i.e. a noise and a movement sensor. Both sensors measure an ambient value and process the values to a color gradient (green > yellow > red). The sensors were built using the Processing 1.5.1 development environment. Available under the GNU LGPL licence version 3 or higher.

  18. Ambient Sensors

    NARCIS (Netherlands)

    Börner, Dirk; Specht, Marcus

    2014-01-01

    This software sketches comprise two custom-built ambient sensors, i.e. a noise and a movement sensor. Both sensors measure an ambient value and process the values to a color gradient (green > yellow > red). The sensors were built using the Processing 1.5.1 development environment. Available under th

  19. Personalidad, ansiedad estado-rasgo e ingreso a la universidad en alumnos preuniversitarios

    Directory of Open Access Journals (Sweden)

    Isabel Niño de Guzmán

    2000-12-01

    Full Text Available Estudio correlacional que identifica las dimensiones de personalidad, el tipo de ansiedad y las características sociodemográficas de alumnos de un centropreuniversitario. Se trabajó con 318 participantes de ambos sexos (43.8% mujeres y 56.2% hombres, que entre 16 y 19 años. Se los evaluó con los siguientes instrumentos: (a NEO PI-R de Costa y McCrae (1992, (b Inventario de Ansiedad Estado-Rasgo de Spielberger (IDARE, 1975 y (c reporte de los tutores. Los resultados confirman la presencia de una estructura factorial básica de cinco dimensiones. Asimismo, revelan correlaciones significativas entre el C.I., características de personalidad asociadas al factor conciencia e ingreso a la universidad. Entre las facetas que correlacionan con el ingreso destaca la autodisciplina. Finalmente, se discuten los resultados.

  20. Det Ambiente

    DEFF Research Database (Denmark)

    Schmidt, Ulrik

    Det ambiente er iscenesættelsen af en karakteristisk sanseoplevelse, der er kendetegnet ved fornemmelsen af at være omgivet. I dag bliver begrebet om det ambiente mest anvendt i forbindelse med musikgenren ’ambient musik’. Det ambiente er dog ikke essentielt knyttet til det musikalske, men må...... forstås som et betydeligt bredere fænomen i den moderne æstetiske kultur, der spiller en væsentlig rolle i oplevelsen af moderne transportformer, arkitektur, film, lydkunst, installationskunst og digitale multimedieiscenesættelser. En forståelse af det ambiente er derfor centralt for forståelsen af en...... moderne æstetiseret oplevelseskultur i almindelighed. Da det ambiente ikke hidtil har været gjort til genstand for en mere indgående teoretisk behandling, er der dog stor usikkerhed omkring, hvad fænomenet overhovedet indebærer. Hovedformålet med Det ambiente – Sansning, medialisering, omgivelse er derfor...

  1. Indian estuaries: Dynamics, ecosystems, and threats

    Digital Repository Service at National Institute of Oceanography (India)

    Shetye, S.R.

    ARTICLE Indian estuaries: Dynamics, ecosystems, and threats Satish R. Shetye National Institute of Oceanography Dona Paula, Goa - 403 004. e-mail: shetye@nio.org Received May 11, 2011 Abstract Indian estuaries have special features that are derived from... the tide pulls the mixed water out of the estuary through its mouth. Different processes within an estuary contribute to mixing of the two waters, the important among these in the Mandovi estuary are: influence of the tide on the advective field within...

  2. Ambient Gestures

    OpenAIRE

    Karam, Maria; Hare, Jonathon; Lewis, Paul; schraefel, m.c.

    2006-01-01

    We present Ambient Gestures, a novel gesture-based system designed to support ubiquitous ‘in the environment’ interactions with everyday computing technology. Hand gestures and audio feedback allow users to control computer applications without reliance on a graphical user interface, and without having to switch from the context of a non-computer task to the context of the computer. The Ambient Gestures system is composed of a vision recognition software application, a set of gestures to be p...

  3. Rasgos de personalidad asociados con la ejecucion de determinados instrumentos musicales

    Directory of Open Access Journals (Sweden)

    Viviana Noemí Lemos de Ciuffardi

    2000-01-01

    Full Text Available El presente estudio tuvo como objetivo evaluar la relación existente entre la ejecución de determinados instrumentos musicales y los rasgos recurrentes de personalidad, en una muestra compuesta por 222 músicos profesionales y alumnos avanzados en el estudio de un instrumento musical. Se utilizó el Revised NEO Personality Inventory (NEO-PI-R de Costa y McCrae (1992, que permite evaluar diferentes rasgos de personalidad basándose en el modelo teórico de los cinco grandes factores de personalidad. Los resultados indicaron que existe una relación significativa entre las familias de instrumentos musicales (cuerdas, vientos bronce, vientos madera y las distintas facetas de personalidad contempladas por el NEO-PI-R (F de Hotelling = .97; P = .017. Esta relación significativa también se observó en los instrumentos específicamente seleccionados: (a flauta traversa, (b clarinete, (c trompeta, (d piano, (e guitarra, y (f saxofón; (F de Hotelling = 2.07; P = .002 Ylos cinco"grandes factores de personalidad que operacionaliza el NEO-PI-R. También se encontró una asociación significativa entre el sexo de los sujetos y la elección de ejecutar determinados instrumentos musicales. Los resultados por familias de instrumentos musicales dieron X2 (4, N~ 208 = 2.23; P = .000 y los resultados por instrumentos específicos elegidos dieron X2 (5, N=76 = 5.37 ; P = .000. Los factores cuyas relaciones resultaron significativas fueron: 1.- Extraversión: (cantidad e intensidad de las interacciones interpersonales. Dentro de este factor las facetas cuyas relaciones puntuaron estadísticamente significativas fueron: (a Sentimiento Gregario, (b Asertividad, (c Búsqueda de Excitación, y (d Emociones Positivas. Los instrumentistas que obtuvieron puntajes más altos en estas facetas fueron los ejecutantes de vientos bronces y quienes obtuvieron los puntajes más bajos fueron los ejecutantes de cuerdas, especialmente la guitarra y también al piano. 2

  4. Rasgos de personalidad, bienestar psicologico y rendimiento academico en adolescentes argentinos

    Directory of Open Access Journals (Sweden)

    Alejandro Castro Solano

    2001-01-01

    Full Text Available Las diferencias individuales en el rendimiento escolar obedecen a tres tipos de factores: los intelectuales, los de aptitud para el estudio y los de personalidad. Los dos primeros han sido ampliamente estudiados. Recientemente comenzaron a surgir investigaciones que señalan que los factores exclusivamente intelectuales son pobres predictores del rendimiento académico a largo plazo y del éxito laboral fuera de los entornos educativos. Una gran cantidad de estudios revela que las variables de personalidad son importantes predictores de las adaptaciones que las personas realizan a los diferentes contextos en los cuales les toca vivir. El enfoque de los cinco factores de personalidad ha sido ampliamente estudiado, sin embargo casi no existen estudios con este enfoque en población adolescente, específicamente estudios locales. El presente trabajo tiene como objetivo replicar la estructura pentafactorial de los rasgos de personalidad en adolescentes de 13 a 19 años. Asimismo se analiza cuales son los rasgos de personalidad que están más relacionados con el logro académico y si existe alguna asociación entre el rendimiento académico y el bienestar autopercibido derivado de la adaptación efectiva a determinados contextos vitales relevantes para los jóvenes. Participaron de este estudio 337 jóvenes que vivían en la Ciudad de Buenos Aires y en el conurbano bonaerense (Argentina. Se aplicó el Cuestionario de los Cinco Factores de Personalidad (BFI de John (1990, como así también una encuesta sobre rendimiento esco- lar y otra sobre satisfacción vital por áreas (Escala D-1 de Andrews y Withey, 1976. Los resultados señalan que en adolescentes argentinos se verifica la misma estructura pentafactorial que en jóvenes estadounidenses. La dimensión conciencia apareció como el componente más relacionado con el mejor rendimiento. La dimensión neuroticismo no diferenciaba entre jóvenes con alto y bajo rendimiento.

  5. Rasgos de personalidad en trastornos de la conducta alimentaria, evolución y gravedad de los síntomas

    OpenAIRE

    Camarillo Gutiérrez, Leticia

    2015-01-01

    El trabajo estudia la relación e influencia de los rasgos de personalidad en los diferentes diagnósticos así como en la gravedad de la sintomatología de los Trastornos de la Conducta Alimentaria. Estos rasgos pueden influir en diferentes síntomas asociados a los Trastornos de la Conducta Alimentaria como son la ansiedad, depresión, abuso de alcohol, impulsividad, la actitud frente a la alimentación y la actitud frente a la propia enfermedad. Se trabaja con el esquema de rasgos de personalida...

  6. FLORA OF MOLOCHNYI ESTUARY COASTS

    Directory of Open Access Journals (Sweden)

    Kolomiychuk V.P.

    2013-09-01

    Full Text Available Present-day characteristic of the coastal flora of Molochnyi eastury is given, that is one of the largest estuaries in Ukraine, the shores and waters of which in 2009 became a part of the Pryazov’ya National Nature Park. The analysis of the main parameters of the flora is made. Rare component of the estuary coastal flora is characterized, further steps to conserve the nature of Pryazov’ya are proposed.

  7. Ambient intelligence

    OpenAIRE

    Sanders, David; Gegov, Alexander

    2006-01-01

    This paper considers some history and the state of the art of Ambient Intelligence and from that seeks to identify new topics and future work. Ubiquitous computing, communications, human-centric computer interaction, embedded systems, context awareness, adaptive systems and distributed device networks are considered.

  8. Ambient intelligence

    CERN Document Server

    Weber, W; Aarts, E

    2005-01-01

    Addresses ambient intelligence used to support human contacts and accompany an individual''s path through the complicated modern world, from applications that are imminent, since they use essentially existing technologies, to ambitious ideas whose realization is still far away, due to major unsolved technical challenges.

  9. Indicadores de ansiedad en el DFH y rasgos de personalidad en niños: un estudio de validez

    Directory of Open Access Journals (Sweden)

    Marcos Antonio Batista

    2014-01-01

    Full Text Available Este estudio tuvo como objetivo la búsqueda de evidencias de validez por medio del análisis de correlación entre los indicadores de ansie - dad de Dibujo de la Figura Humana – DFH - de Karen Machover y la Escala de Rasgos de Personalidad para Niños (ETPPC . Participaron 240 niños, de ambos sexos, con edades comprendidas entre 8 y 10 años, estudiantes de enseñanza básica de la red pública de Brasil. Por medio de los análisis de correlación se demostró que cuando los indicadores DFH son agrupados, existen correlaciones significativas con los rasgos de personalidad, y corroborado con lo esperado, se puede inferir que hay características que convergen una vez que la ansiedad es apenas parte del constructo de rasgos de personalidad como el neuroticismo y la extroversión.

  10. Rasgos psicopáticos infanto-juveniles: evaluación e implicaciones en un estudio prospectivo

    Directory of Open Access Journals (Sweden)

    Estrella Romero

    2016-01-01

    Full Text Available En este trabajo se analizan los datos de un estudio longitudinal a largo plazo con el objetivo de examinar las implicaciones de los rasgos psicopáticos infanto-juveniles, evaluados a través de la mCPS (modified Child Psychopathy Scale, en la conducta antisocial en la adolescencia. Se analizan los datos recogidos en 141 niños (edad media = 7.80, que fueron seguidos seis y diez años más tarde. Los resultados muestran que los niños con altas puntuaciones en rasgos psicopáticos presentan en la adolescencia temprana niveles relativamente altos de problemas de conducta. Además, a lo largo de la adolescencia se produce en ellos un mayor incremento en implicación con amigos antisociales, consumo de cannabis y agresión proactiva. Así, los resultados muestran que los rasgos psicopáticos medidos en la niñez se asocian con un desarrollo más desfavorable, particularmente en indicadores que, como la agresión proactiva, se han vinculado clásicamente a la personalidad psicopática en adultos.

  11. Rasgos Pedagógicos de los Objetos de Aprendizaje Pedagogical Features of Learning Objects

    Directory of Open Access Journals (Sweden)

    Chiappe Laverde Andres

    2008-07-01

    Full Text Available Los objetos de aprendizaje (OA son considerados hoy como una alternativa viable e interesante para el desarrollo de contenidos para programas educativos mediados por las Tecnologías de la Información y la Comunicación (TIC. No obstante la pertinencia del tema para el momento actual de la educación superior en toda Latinoamérica, es preciso reflexionar más en profundidad acerca de lo que significan los OA y su impacto en el proceso educativo. El estudio de los rasgos pedagógicos de los objetos de aprendizaje coloca a la comunidad académica frente a un escenario que requiere la pronta identificación de sus retos y limitaciones de cara a la inminente ejecución de procesos de incorporación de los OA en las dinámicas de las instituciones educativas. Learning objects (LO are regarded today as a viable and interesting alternative for development of content for educational programs mediated by information and communication technologies (ICT. Attending the relevance of this topic just for this historic moment of higher education throughout Latin America, we need to think more deeply about what LO means and its impact on the educational process. The study of the pedagogical features of learning objects placed to the academic community in front of a scenario that requires prompt identification of their challenges and constraints facing the imminent execution of incorporation processes of LO in educational institutions dynamics.

  12. KNOW YOUR ESTUARY: THE WATER THROUGH TIME

    Science.gov (United States)

    This presentation will focus on historical changes in water quality in the Yaquina Estuary, Oregon, and factors which influence water quality within this estuary. Topics presented will include the importance of ocean conditions on water quality in the estuary; historical changes...

  13. Análisis intra e inter poblacional de rasgos craneanos no metricos en aborigenes prehispanicos del actual territorio de Córdoba

    Directory of Open Access Journals (Sweden)

    Fabra, Mariana

    2005-01-01

    Full Text Available Recientes investigaciones acerca de la arqueología de sociedades agroalfareras del territorio que actualmente ocupa la provincia de Córdoba, señalan que existió un proceso de diversificación e intensificación diferencial, que terminó definiendo modalidades regionales en los estilos de vida de dichas comunidades. Desde esta perspectiva, los desarrollos llevados a cabo en las sierras y la llanura extraserrana de las zonas centro y sur de Córdoba, difieren en algunos aspectos de aquellos implementados en la zona norte y a su vez, estos dos de los grupos de Traslasierra y San Luis. En este estudio se investigó, a través del análisis de rasgos craneanos no métricos, si esta diversificación cultural se correspondió con diferencias biológicas regionales. Varias técnicas de análisis utilizadas (cluster análisis, autocorrelación espacial y multi-response permutation procedure, permitieron identificar un patrón de agrupamiento regional entre las poblaciones que se asentaron en los diferentes valles serranos, no así las que ocuparon los ambientes de llanura. Por otra parte, al confrontarse la serie Córdoba con otras de Argentina a partir de datos extraídos de la literatura, se puso de manifiesto que Córdoba presenta una mayor similitud con los grupos de Patagonia y Tierra del Fuego, que con los del Noroeste y Noreste de Argentina. A su vez, se evidenció una neta diferenciación entre Córdoba y las restantes series.

  14. Biogeochemical budgets for Tapi Estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Bapardekar, M.V.; DeSousa, S.N.; Zingde, M.D.

    , is rural with no sewage facilities. The urban population is spread over 37 cities (7 class I cities with population >100,000; 7 class II cities with population between 50,000 and 100,000; and 23 class III cities with population ranging between 20..., chemical and metallurgical. All these industries release their effluents in the adjacent estuary. A considerable amount of sewage generated in and around the Surat city is released to the inner segment of the estuary. The average annual ground water...

  15. Ambient intelligence

    CERN Document Server

    Basten, Twan; de Groot, Harmke

    2007-01-01

    ""This book is truly an eye-opener as it is the first book that relates the dream scenarios of Ambient Intelligence quantitatively to the technical challenges and requirements of the huge distributed and interoperable embedded systems needed to implement AmI systems in the real world. This book is strongly recommended to a wide spectrum of engineers interested to embark in this rapidly emerging and fascinating technology."" (From the foreword by Hugo De Man, Professor K.U. Leuven and Senior Research Fellow IMEC)

  16. Rasgos instrumentales (masculinos y expresivos (femeninos, normativos (típicos e ideales en México

    Directory of Open Access Journals (Sweden)

    Rolando Díaz Loving

    2001-01-01

    Full Text Available Diversas investigaciones han demostrado reiteradamente que los rasgos instrumentales (masculinos y expresivos (femeninos, asignados tradicionalmente de manera diferencial a hombres y mujeres, en realidad se derivan de procesos de socialización y endoculturación que en la actualidad y en algunas culturas ha hecho que estos rasgos.se presenten intensiva e indistintamente en ambos sexos. El desarrollo de instrumentos de medición de estas características y su validación en diversas culturas ha mostrado lo robusto de un constructo teórico multidimensional y dualista que permite no sólo describir de manera clara a las personas, sino que además, demuestra el papel central que juega la normatividad sociocultural en el desarrollo de dichas características. Estos conocimientos y la teoría que los sustenta, han permitido el desarrollo de medidas nuevas de masculinidad y feminidad, que por demostrar el predominio de factores sociales sobre los genéticos, pudieran manifestarse a través de distintas definidoras al ir de una cultura a otra. Con el objeto de identificar los atributos instrumentales y expresivos que describen a hombres y mujeres mexicanas, se realizaron una serie de grupos de enfoque de donde se derivaron 323 adjetivos correspondientes a estas dos dimensiones. Posteriormente, para obtener la normatividad de cada atributo, se aplicó un inventario en el que se pidió a 856 sujetos divididos por sexo y nivel educativo que indicaran qué tan típico e ideal era que hombres y mujeres poseyeran dichos rasgos. Los resultados muestran listados de características expresivas e instrumentales típicas e ideales que fueron reportadas como socialmente deseables o indeseables tanto para hombres como para mujeres. Las listas obtenidas se discuten en términos de género y cultura.

  17. Rasgos funcionales en el género Quercus: estrategias adquisitivas frente a conservativas en el uso de recursos

    Directory of Open Access Journals (Sweden)

    E. G. de la Riva

    2014-01-01

    Full Text Available Las especies del género Quercus constituyen uno de los grupos más abundantes e importantes de plantas leñosas de la Península Ibérica, estando su distribución determinada por la disponibilidad de agua, el tipo de suelo y la historia del manejo. El conocimiento de la variación de sus características morfo-funcionales puede ayudarnos a comprender el grado de diversificación de las especies del mismo género y los mecanismos que controlan sus patrones de distribución. Los objetivos principales de este estudio son: (i analizar las relaciones existentes entre los diferentes rasgos funcionales dentro del género Quercus y testar cómo se ajustan a las estrategias de captación de recursos; y (ii comprobar si existe coordinación entre los rasgos medidos a nivel de hoja, tallo y raíz. El muestreo se llevó a cabo en Sierra Morena (Córdoba y la Sierra del Aljibe (Cádiz, cuantificándose rasgos funcionales claves a nivel de hoja, tallo, raíz, tamaño de planta y fisiología en cinco especies de Quercus (Q. canariensis, Q. coccifera, Q. faginea, Q. ilex y Q. suber. Los resultados muestran que las diferentes especies de Quercus presentan claros patrones en sus estrategias funcionales que están relacionados con su distribución, encontrando un gradiente desde especies más conservativas en el uso de recursos en condiciones de menor disponibilidad de agua a especies más adquisitivas en zonas más húmedas. A su vez, se aprecia una coordinación entre los patrones de rasgos funcionales encontrados a nivel de hoja, tallo y de raíz que apoya la existencia de un “espectro de economía” a nivel de la planta entera.

  18. El lenguaje de los niños ciegos y la cuestión de los rasgos autistas

    OpenAIRE

    Miguel Pérez Pereira

    2000-01-01

    Hobson et al. (Brown, Hobson. Lee y Stevenson, 1997; Hobson, Brown, Minter y Lee, 1997) han investigado la similitud entre el autismo y la ceguera congénita. En este artículo se revisa la evidencia empírica a favor de la existencia de rasgos autistas en el lenguaje de los niños ciegos de nacimiento, a la vez que se aportan nuevos datos de investigaciones del autor. Se centra el interés en (a) el uso de los pronombres personales, (b) el uso de imitaciones y habla formuláica, (c) el uso egocént...

  19. Análisis ontogénico de rasgos craneofaciales robustos en poblaciones humanas de Patagonia

    OpenAIRE

    González, Paula N.

    2007-01-01

    Las poblaciones humanas que habitaron el sur de Patagonia durante el Holoceno tardío presentan rasgos craneofaciales robustos que las diferencian del resto de los humanos modernos. El estudio de los factores causales de la robustez se ha basado en el análisis de individuos adultos, por lo tanto los mecanismos ontogénicos involucrados en la diferenciación de estas poblaciones son aún desconocidos. El objetivo de este trabajo es analizar la ontogenia de la robustez craneofacial en diversas pobl...

  20. Competencias y rasgos de la ética profesional en los posgrados de la Universidad Iberoamericana-Puebla

    Directory of Open Access Journals (Sweden)

    J. Martín López Calva

    2009-01-01

    Full Text Available En este artículo presentamos los avances de la investigación sobre las competencias y los rasgos de la ética profesional entre los docentes y estudiantes de posgrado de la Universidad Iberoamericana-Puebla, que constituyen los resultados parciales de un proyecto interuniversitario en el que participan quince instituciones mexicanas de educación superior. El objetivo es llegar a proponer lineamientos para la formación de una profesionalidad ética en los posgrados de las universidades del país.

  1. Conciencia ambiental y conducta sustentable relacionada con el uso de energía para iluminación

    Directory of Open Access Journals (Sweden)

    Graciela Lucía Tonello

    2015-06-01

    Full Text Available La conciencia ambiental es definida como un concepto multidimensional que constituye la dimensión actitudinal del comportamiento pro ambiental. En un contexto global y local de crisis energética, el presente trabajo tuvo como objetivos investigar las interrelaciones entre las diferentes dimensiones de la conciencia ambiental y la posible sustentabilidad detrás de conductas relacionadas con el uso de la iluminación, en una muestra de estudiantes universitarios. La metodología incluyó el desarrollo y administración de una encuesta con diferentes secciones para estimar la conciencia ambiental mediante escalas clasificatorias y preguntas sobre percepción de problemas ambientales, la atribución de responsabilidades, escalas estandarizadas de preocupación ambiental, conocimientos ambientales y la propensión al futuro como un rasgo de la personalidad sustentable. Los resultados en general muestran que la temática energética, al menos la referida a la iluminación tomada en este estudio, no es percibida como problemática ambiental sino como una problemática que afecta a nivel individual, y la perspectiva temporal de futuro evidenciada por la muestra está referida al tiempo futuro en sí mismo, más que como rasgo de personalidad sustentable.

  2. Los rasgos de la lírica del exilio en la poética de Luis Cernuda

    Directory of Open Access Journals (Sweden)

    Ana Martínez García

    2015-01-01

    Full Text Available La obra literaria creada en el destierro por los españoles tuvo ciertos caracteres esenciales que le llevan a formar parte de una tendencia distinta, a no ligarse a los movimientos literarios coetáneos que se manifestaban en la península. La lírica fue el género más influenciado por la situación que los exiliados estaban experimentando, razón por la que sus textos pueden dividirse en periodos, con diferentes rasgos, dependientes de la situación histórica que experimentaban: Segunda Guerra Mundial, final de la guerra y afianzamiento del Franquismo, etc. Entre los muchos autores exiliados, Luis Cernuda fue uno de los más reconocidos, donde los rasgos de la poética del destierro estaban presentes, de una forma velada, trágica y sucinta, como era propio de toda su producción.

  3. Estuary-wide genetic stock distribution - Columbia River Estuary Tidal Habitats

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The goal of the tidal-fluvial estuary study is to determine the estuary's contribution to the spatial structure and life history diversity of Columbia River salmon...

  4. In-stream PIT detection, estuary wetlands - Columbia River Estuary Tidal Habitats

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The goal of the tidal-fluvial estuary study is to determine the estuary's contribution to the spatial structure and life history diversity of Columbia River salmon...

  5. Salmon habitat use, tidal-fluvial estuary - Columbia River Estuary Tidal Habitats

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The goal of the tidal-fluvial estuary study is to determine the estuary's contribution to the spatial structure and life history diversity of Columbia River salmon...

  6. Mantenimiento o sustitución de rasgos lingüísticos indexados socialmente: migrantes de zonas andinas en Lima

    OpenAIRE

    Carola Mick; Azucena Palacios

    2013-01-01

    ResumenEste artículo investiga la relación entre la formación de “mundos de vida comunicativos individuales” y la construcción de la identidad en migrantes peruanas procedentes de la zona de los Andes en Lima. A partir del análisis lingüístico y discursivo de un corpus de entrevistas semidirigidas con veintidós mujeres migrantes mostramos cómo las ideologías lingüísticas, las que menosprecian rasgos dialectales considerados como típicos de migrantes andinos y las que prestigian los “rasgos li...

  7. Morphodynamic equilibrium of alluvial estuaries

    Science.gov (United States)

    Tambroni, Nicoletta; Bolla Pittaluga, Michele; Canestrelli, Alberto; Lanzoni, Stefano; Seminara, Giovanni

    2014-05-01

    The evolution of the longitudinal bed profile of an estuary, with given plan-form configuration, subject to given tidal forcing at the mouth and prescribed values of water and sediment supply from the river is investigated numerically. Our main goal is to ascertain whether, starting from some initial condition, the bed evolution tends to reach a unique equilibrium configuration asymptotically in time. Also, we investigate the morphological response of an alluvial estuary to changes in the tidal range and hydrologic forcing (flow and sediment supply). Finally, the solution helps characterizing the transition between the fluvially dominated region and the tidally dominated region of the estuary. All these issues play an important role also in interpreting how the facies changes along the estuary, thus helping to make correct paleo-environmental and sequence-stratigraphic interpretations of sedimentary successions (Dalrymple and Choi, 2007). Results show that the model is able to describe a wide class of settings ranging from tidally dominated estuaries to fluvially dominated estuaries. In the latter case, the solution is found to compare satisfactory with the analytical asymptotic solution recently derived by Seminara et al. (2012), under the hypothesis of fairly 'small' tidal oscillations. Simulations indicate that the system always moves toward an equilibrium configuration in which the net sediment flux in a tidal cycle is constant throughout the estuary and equal to the constant sediment flux discharged from the river. For constant width, the bed equilibrium profile of the estuarine channel is characterized by two distinct regions: a steeper reach seaward, dominated by the tide, and a less steep upstream reach, dominated by the river and characterized by the undisturbed bed slope. Although the latter reach, at equilibrium, is not directly affected by the tidal wave, however starting from an initial uniform stream with the constant 'fluvial' slope, the final

  8. Carbon dioxide emissions from Indian monsoonal estuaries

    Digital Repository Service at National Institute of Oceanography (India)

    Sarma, V.V.S.S.; Viswanadham, R.; Rao, G.D.; Prasad, V.R.; Kumar, B.S.K.; Naidu, S.A.; Kumar, N.A.; Rao, D.B.; Sridevi, T.; Krishna, M.S.; Reddy, N.P.C.; Sadhuram, Y.; Murty, T.V.R.

    be completely different from those in dry period. Recently Sarma et al. (2011) reported record levels of partial CO 2 pressures (pCO 2 ) of >30,000 μatm in the Godavari estuary during discharge period of 2008 whereas close to atmospheric saturation... was noticed during dry period. Similarly, enhanced pCO 2 levels during discharge period was also noticed in other Indian estuaries, such as Mandovi-Zuari (Sarma et al., 2001), Cochin estuary (Gupta et al., 2009), Chilka estuary (Gupta et al., 2008) whereas...

  9. El papel del mercado del suelo en la configuración de algunos rasgos socioespaciales de las ciudades latinoamericanas

    Directory of Open Access Journals (Sweden)

    Samuel Jaramillo

    1999-01-01

    Full Text Available Una interrogación central orienta la exploración adelantada en este artículo, ¿existen peculiaridades en el funcionamiento de los mercados de tierra en las ciudades latinoamericanas? En contra de lo que suele pensarse entre los especialistas de este tema, este trabajo sostiene que las formas de operación del mercado del suelo urbano en las ciudades latinoamericanas obedece a los patrones generales encontrados en ciudades capitalistas. No obstante, a causa de la presencia de condiciones sociales, políticas y económicas muy particulares de la ciudad latinoamericana, la organización socioespacial de esta ciudad tiene rasgos muy peculiares, presentes a lo largo y ancho del continente. Estos rasgos derivan en parte de las especificidades del proceso de acumulación latinoamericano, caracterizado por ser un régimen de bajos salarios, con grandes desigualdades sociales, un acelerado crecimiento urbano, debilidad estructural del aparato estatal, con presencia de significativos obstáculos a la homogeneización capitalista de la producción de espacio construído. A pesar de la diversidad nacional latinoamericana, sus ciudades han ido configurándose en torno de ciertos rasgos comunes, muy específicos de la región: alejamiento permanente de las élites en una misma dirección, cada vez más lejana del centro histórico, una aparente decadencia socioeconómica de este mismo centro, y una secular segregación socioespacial y heterogeneidad en la producción del espacio. En cada uno de estos casos el mercado ha operado como uno de los reguladores centrales del comportamiento económico, contribuyendo a la gestación de las características mencionadas. No obstante, en algunos casos, sus formas de operación han sido opuestas a las comunmente aceptadas: la salida de las elites del centro sería en parte voluntaria y en parte obligada por la competencia impuesta por otros usos, más populares, altamente rentables; esta salida esta léjos de

  10. Rasgos de historia de vida de especies pioneras en la Reserva Natural Ibanasca (Ibagué, Tolima, Colombia

    Directory of Open Access Journals (Sweden)

    Gómez Ruíz, Pilar Angélica

    2006-12-01

    Full Text Available Los rasgos de historia de vida (RHV son cualidades o atributos propios de cada individuo que representan
    respuestas en aspectos fisiológicos, morfológicos, anatómicos y ecológicos ante las condiciones ambientales
    presentes. En la Reserva Natural Ibanasca se seleccionaron 17 especies de plantas leñosas pioneras y en cada una se evaluaron 18 rasgos relacionados con las fases de dispersión, establecimiento y persistencia con el fin de establecer agrupaciones entre las especies. Con base en un Análisis de Conglomerados se obtuvieron cinco
    grupos en los análisis general y morfológico y cuatro grupos en el análisis de semilla. Además, se estableció
    las correlaciones entre algunas variables obteniendo que altura-área foliar y número de semillas por fruto-área
    foliar se correlacionaban positivamente. Solanum sycophanta, Croton magdalenesis y Brunellia colombiana se agruparon por ser las especies de mayor altura mientras que Inga sp. y Citharexylum subflavecens son las especies de semillas más grandes y pesadas, también están Montanoa quadrangularis y Bocconia frutescens como las especies de mayor tase relativa de crecimiento al tener las mayores áreas específicas foliares y siempre aparte se encontró a Cecropia cf. mutisiana por ser de las más altas, mayor área foliar y mayor producción de semillas. Con
    base en los resultados obtenidos se considera que los rasgos que mejor caracterizan a este grupo de especies son: abundante producción de semillas de fácil dispersión, tasa de crecimiento rápida representada en un área específica foliar grande, tamaños de hoja grandes manifestados en áreas foliares grandes, capacidad de
    regeneración vegetativa, abundante producción de hojarasca y ser heliófilas (tolerantes a la luz. Con base en
    lo anterior pueden proponerse las siguientes especies para una futura restauración ecológica de la Reserva:
    Cecropia cf. mutisiana, Bocconia

  11. El lenguaje de los niños ciegos y la cuestión de los rasgos autistas

    Directory of Open Access Journals (Sweden)

    Miguel Pérez Pereira

    2000-12-01

    Full Text Available Hobson et al. (Brown, Hobson. Lee y Stevenson, 1997; Hobson, Brown, Minter y Lee, 1997 han investigado la similitud entre el autismo y la ceguera congénita. En este artículo se revisa la evidencia empírica a favor de la existencia de rasgos autistas en el lenguaje de los niños ciegos de nacimiento, a la vez que se aportan nuevos datos de investigaciones del autor. Se centra el interés en (a el uso de los pronombres personales, (b el uso de imitaciones y habla formuláica, (c el uso egocéntrico del lenguaje, y (d la capacidad de iniciar conversaciones y de contingencia conversacional. El análisis pone en cuestión la supuesta similitud entre los niños ciegos y los autistas, además parece refutar la teoría de Hobson.

  12. Rasgos de sentido de vida del enfoque de resiliencia en personas mayores entre 65 y 75 años

    Directory of Open Access Journals (Sweden)

    Jiménez Segura, Flor

    2004-12-01

    Full Text Available La resiliencia es la capacidad para activar las fortalezas y proteger la integridad personal al enfrentar adversidades, construyendo a partir de éstas. En este estudio se identificaron los ocho rasgos de sentido de vida según el enfoque de resiliencia (Intereses especiales, Metas, Motivación para el logro, Aspiraciones educativas, Optimismo, Persistencia, Fe y Espiritualidad y Sentido de propósito, que han presentado personas adultas mayores de 65 a 75 años durante sus vidas. Los principios teórico-metodológicos utilizados son los del paradigma cualitativo. Se efectuaron entrevistas en profundidad a cuatro mujeres y cuatro hombres que pertenecen al grupo de Envejecimiento Integral de la Universidad de Costa Rica o a la Asociación Gerontológica Costarricense. Aunque la mayoría de las personas adultas mayores participantes en el estudio no identificaron metas claras en la actualidad, durante sus vidas contaron con las condiciones y herramientas personales que contribuyeron con el desarrollo de los rasgos de sentido de vida del enfoque de resiliencia. The concept of resilience centers around the human capacity to rise from adversities and to be strengthened by them. Traits of the Sense of Purpose component of a resilience model (Special interests, Goal directedness, Achievement motivation, Educational aspirations, Hopefulness, Persistence, Faith and Spirituality, and Meaningfulness were identified in older persons 65 to 75 years of age. In-depth interviews were conducted with four women and men who participate in programs that promote healthy development in older adults. Although most of the persons interviewed had difficulty specifying present goals, during their lives and currently they have had the environmental and personal conditions for the strengthening of the traits identified with the presence of a sense of purpose.

  13. Análisis ontogénico de rasgos craneofaciales robustos en poblaciones humanas de Patagonia

    Directory of Open Access Journals (Sweden)

    González, Paula N.

    2007-01-01

    Full Text Available Las poblaciones humanas que habitaron el sur de Patagonia durante el Holoceno tardío presentan rasgos craneofaciales robustos que las diferencian del resto de los humanos modernos. El estudio de los factores causales de la robustez se ha basado en el análisis de individuos adultos, por lo tanto los mecanismos ontogénicos involucrados en la diferenciación de estas poblaciones son aún desconocidos. El objetivo de este trabajo es analizar la ontogenia de la robustez craneofacial en diversas poblaciones humanas. Se analizaron 5 muestras de individuos subadultos (Sad, de 5 a 15 años y adultos (Ad, procedentes del Noroeste Argentino y Patagonia (n=201. Se emplearon landmarks y semilandmarks con el fin de describir la glabela, los procesos frontal y zigomático, y el mastoides. Para establecer si los rasgos poblacionales específicos se encuentran presentes en Sad se compararon los patrones de ordenación de Ad y Sad obtenidos mediante un análisis de PROTEST. Los resultados indican que el patrón de variación morfológica se establece tempranamente en Sad. Se evaluó si la diferenciación en los Ad de las diversas poblaciones es atribuible al escalamiento ontogénico o a diferencias en las trayectorias. Los resultados muestran que si bien las poblaciones del sur alcanzan un mayor tamaño, las trayectorias ontogénicas entre las poblaciones estudiadas difieren significativamente. Por lo tanto, la robustez se establece tempranamente en la ontogenia postnatal y es modificada por la divergencia en los patrones de cambio en forma asociados a los cambios en tamaño.

  14. Rasgos postmodernos de la educación ambiental. Una formación pertinente con las nuevas corrientes de pensamiento

    OpenAIRE

    Francisco Javier Perez Rodriguez; Joselin del Valle Albujar Sánchez

    2015-01-01

    Los problemas ambientales que se suscitan a escala global son evidencia de una crisis, la cual es expresión de una coyuntura más profunda que trastoca los fundamentos del pensamiento de la humanidad en toda una era. Esta situación tiene sus causas primigenias en el modo general de conocer que desde el Renacimiento se implantó en gran parte del mundo occidental y que erigió al desarrollo y al progreso como idearios, hecho que finalmente se tradujo en una relación insostenible entre los humanos...

  15. ambientes mediterráneos

    Directory of Open Access Journals (Sweden)

    G. Escribano-Ávila

    2015-01-01

    Full Text Available A nivel global, dos tendencias opuestas gobiernan el uso de la tierra: la intensificación y el abandono. Esta última supone una oportunidad para larecuperación de los ecosistemas, una necesidad urgente dada la actual crisis ambiental. La comunidad de dispersores frugívoros es determinantepara recuperar la estructura y complejidad de la vegetación en campos abandonados, ya que éstos suelen estar desprovistos de propágulos.Recientes estudios han resaltado la especial relevancia de los mamíferos frugívoros en el proceso de dispersión de semillas en ambientesdegradados como los campos abandonados. Esto es debido a una serie de rasgos morfológicos y de comportamiento que caracterizan a losfrugívoros mamíferos y que les hace ser dispersores especialmente efectivos. Generalmente los mamíferos frugívoros tienen un mayor tamañocorporal, mayores áreas de campeo y distancias de dispersión, frecuente uso de hábitats abiertos, movilizando así más semillas hasta los camposabandonados que otros grupos de frugívoros (e.g. aves. Una vez que una semilla ha sido depositada tiene que superar las sucesivas etapas hastael establecimiento (depredación post-dispersiva, germinación, supervivencia y crecimiento. Los mamíferos frugívoros favorecen todo este procesoen mayor medida que otros dispersores. A nivel interespecífico pueden dispersar mayor diversidad de especies al estar generalmente menoslimitados por el tamaño de fruto, y a nivel intra-especifico no seleccionan semillas de pequeño tamaño. Además, suelen depositar las semillas enmicrohábitats que resultan especialmente adecuados para el reclutamiento. En consecuencia, los mamíferos son un elemento clave en los ensamblesde frugívoros que propician la regeneración de los campos abandonados y su función ecológica debe ser considerada en la restauración y manejode hábitats degradados.Palabras clave: áreas degradadas; bosque remanente; cambio de los usos del suelo; dispersi

  16. Diet-induced developmental plasticity in life histories and energy metabolism in a beetle La dieta induce plasticidad del desarrollo en los rasgos de historia de vida y metabolismo energético en un escarabajo

    Directory of Open Access Journals (Sweden)

    SERGIO URREJOLA

    2011-12-01

    Full Text Available Adaptive phenotypic plasticity, has been recognized as an important strategy by which organisms maximize fitness in variable environments, which vary through development. A disassociation among stages should represent a null effect of the environment experienced during early ontogeny in the expression of adult traits. Food quality greatly influences survival, development and reproduction in many arthropod herbivores. We examined the effects of diet protein in physiological and life-history traits in the yellow mealworm beetle Tenebrio molitor through ontogeny. We established four experimental treatments: Low Protein (LP, Low Protein Control (LPC, High Protein (HP, and High Protein Control (HPC with recently eclosioned larvae each. Individuals were maintained on the same diet or transferred to the opposite diet for all pupae period and almost all adult period. Contrary to the expected, the duration of life-cycle, larval growth rate and body mass in T. molitor were similar in diet treatments. We found intra-individual trade-offs between environmental diet (rich or poor in protein content during larval phase and egg number. Larvae fed on a protein-deficient diet exhibited significantly higher respiratory rates than larvae fed on a rich protein diet. Compensatory feeding could act in T. molitor larvae indicating differences in metabolism but not in growth rate, body mass and life-cycle characteristics. Our results demonstrate the plasticity of reproductive and metabolic traits and life-cycle characteristics of T. molitor and how changes that occur in relation to diet can have profound effects on progeny and female fitness.La plasticidad fenotípica adaptativa ha sido reconocida como una estrategia importante por el cual los organismos maximizan su adecuación biológica en ambientes variables y la cual varía a lo largo del desarrollo. En los organismos la plasticidad fenotípica generalmente se refiere a como los diferentes tipos de rasgos pueden

  17. ANSIEDAD, DEPRESIÓN Y RASGOS DE PERSONALIDAD EN PACIENTES CON INSUFICIENCIA VENOSA CRÓNICA PERIFÉRICA

    Directory of Open Access Journals (Sweden)

    L A Carmona-López

    2016-07-01

    Full Text Available Introducción: La Insuficiencia Venosa Crónica Periférica (IVCP es un cambio clínico que se produce como resultado de la dilatación patológica de las venas en los miembros inferiores, de la incompetencia de sus válvulas y de la hipertensión venosa resultante. Pudiera cursar dentro de la categoría de trastornos sistémicos que producen depresión y ansiedad, las cuales a su vez son alteraciones psiquiátricas relacionadas con toda la esfera cardiovascular. Objetivo: Determinar la frecuencia de ansiedad, depresión y su relación con los rasgos de personalidad, en pacientes con Insuficiencia Venosa Crónica Periférica. Metodología: Se realizó un trabajo de tipo descriptivo, de corte transversal. Se utilizó la escala de Hamilton para ansiedad y depresión; la personalidad fue evaluada con el cuestionario Factorial de Personalidad 16 FP de Catell además de otras variables sociodemográficas. Resultados: Se evaluaron 30 pacientes; 93% (N=28 de sexo femenino, 7% (N=2 de sexo masculino diagnosticados. Con edades entre 25 y 74 años; encontrándose 36,7% (N=11 ansiedad severa, seguida de ansiedad menor en 33,3% (N=10. 50% de los pacientes no presentó depresión, y 50% se distribuyó de forma homogénea en leve, moderada y severa. Predominando personalidad que se le dificulta manejar las frustraciones, suelen ser nerviosos o ansiosos ante ciertas circunstancias, suspicaces, inteligentes y leales a nivel grupal. El rasgo de personalidad que predominó en el grupo de estudio es el de tipo ansioso. Conclusión: Los pacientes con insuficiencia venosa crónica periférica tienen inclinación a la ansiedad con dificultades para manejar la frustración. Palabras claves: Insuficiencia venosa, Ansiedad, Depresión, Personalidad

  18. National Estuary Program Study Area Boundaries

    Data.gov (United States)

    U.S. Environmental Protection Agency — There are 28 National Estuary Programs (NEPs) in the U.S.that implement habitat protection and restoration projects with their partners. This work takes place...

  19. Carbon isotope geochemistry in the Yalujiang estuary

    Institute of Scientific and Technical Information of China (English)

    吴莹; 张经

    2001-01-01

    The distribution of particulate organic carbon (POC) along the lower reaches is similar between the dry season and the flood season in the Yalujiang Estuary, North China. However, the values of particulate organic carbon of the upperstream in the dry season are one magnitude lower than the concentrations in the flood season. Stable carbon isotope ratios have been used to study the sources of particulate organic carbon in the Yalujiang Estuary. The isotopic composition of POC shows a range from -23.1‰ to -29.4‰ with a little seasonal variation. The isotopic evidence indicates that the POC in the Yalujiang Estuary is predominantly of terrestrial origin rather than a result of in situ plankton. The study of the ratio of POC: Chla shows that the turbidity maximum plays an important role in POC cycle in the Yalujiang Estuary. Organic detritus and soil erosion are the main contributions to POC in the turbidity maximum, especially in the flood season.

  20. Mercury in sediments of Ulhas estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Ram, A.; Rokade, M.A.; Borole, D.V.; Zingde, M.D.

    Hg levels in water, suspended particulate matter and sediment of the Ulhas estuary are under considerable environmental stress due to the indiscriminate release of effluents from a variety of industries including chlor-alkali plants. Concentration...

  1. Microplastic in three urban estuaries, China.

    Science.gov (United States)

    Zhao, Shiye; Zhu, Lixin; Li, Daoji

    2015-11-01

    Estuarine Microplastics (MPs) are limited to know globally. By filtering subsurface water through 330 μm nets, MPs in Jiaojiang, Oujiang Estuaries were quantified, as well as that in Minjiang Estuary responding to Typhoon Soulik. Polymer matrix was analyzed by Raman spectroscopy. MP (plastics. The highest MPs density was found in Minjiang, following Jiaojiang and Oujiang. Fibers and granules were the primary shapes, with no pellets found. Colored MPs were the majority. The concentrations of suspended microplastics determine their bioavailability to low trophic organisms, and then possibly promoting the transfer of microplastic to higher trophic levels. Polypropylene and polyethylene were the prevalent types of MPs analyzed. Economic structures in urban estuaries influenced on MPs contamination levels. Typhoon didn't influence the suspended MP densities significantly. Our results provide basic information for better understanding suspended microplastics within urban estuaries and for managerial actions. PMID:26312741

  2. Mixing in the Amazon estuary

    Science.gov (United States)

    Bezerra, M. O.

    2010-05-01

    The research area of this work is located at the estuary of the Amazon River (Brazil), near the river mouth. The results of air movement analysis on the surface atmospheric circulation over the Mouth of the Amazonas River, salinity and temperature measures as well as measurements of currents, carried out along a longitudinal section in the navigation canal region of the Northern Bar of the Amazon River (Barra Norte do Rio Amazonas) in June 2006, during the river flood season in the quadrature tide. The dynamics effects affect hydrodynamic,meteorological and hydrographical parameters at the river mouth. The conclusion drawn include that: a) the saline wedge-type stratification can be detected approximately 100km away from the mouth of the Amazon River during the end of the rainy season in the quadrature tide; b) probably, at the Amazon estuary the quadrature entrainment processes are dominant and they are the ones responsible for increased salinity detected in the surface layer, whereas turbulence scattering mixing is not so important. c) The large flow of fresh water from the Amazon River at the end of the rainy season implies the displacement of the saline front position over the internal Amazon continental platform, and d) The tidal wave shows a positive asymmetry in the canal, with floods lasting less than in the ebb tide. This asymmetry decreases towards the ocean, eventually becoming reversed in the presence of a saline wedge. The speeds, however, have a negative asymmetry, with more intense ebb tides, due to the river flow and is more evident by the existence of quadrature tides.

  3. Rasgos socioculturales de los jóvenes en México: bienestar, cultura y política

    Directory of Open Access Journals (Sweden)

    Luz María Ortega Villa

    2016-01-01

    Full Text Available Con base en dos encuestas nacionales aplicadas por el gobierno mexicano, se presenta un análisis secundario de las bases de datos de la Encuesta Nacional de Juventud 2010 y la Encuesta Nacional de Cultura Política de 2012, para analizar la situación de los jóvenes mexicanos en algunos aspectos de su bienestar y sexualidad, consumo y acceso a bienes culturales, sus interacciones con otros, y la cultura política que practican. A pesar de las limitaciones de la Encuesta Nacional de Juventud 2010 y su aplicación, se delinean algunos rasgos que permiten conocer a las y los jóvenes mexicanos: condición laboral y educativa, patrones de interacción específicos según edad, un marcado sedentarismo, escasas expresiones de la subjetividad, muy poco interés y participación en la política institucional, y la desconfianza hacia sus protagonistas.

  4. Bar dimensions and bar shapes in estuaries

    Science.gov (United States)

    Leuven, Jasper; Kleinhans, Maarten; Weisscher, Steven; van der Vegt, Maarten

    2016-04-01

    Estuaries cause fascinating patterns of dynamic channels and shoals. Intertidal sandbars are valuable habitats, whilst channels provide access to harbors. We still lack a full explanation and classification scheme for the shapes and dimensions of bar patterns in natural estuaries, in contrast with bars in rivers. Analytical physics-based models suggest that bar length in estuaries increases with flow velocity, tidal excursion length or estuary width, depending on which model. However, these hypotheses were never validated for lack of data and experiments. We present a large dataset and determine the controls on bar shape and dimensions in estuaries, spanning bar lengths from centimeters (experiments) to 10s of kilometers length. First, we visually identified and classified 190 bars, measured their dimensions (width, length, height) and local braiding index. Data on estuarine geometry and tidal characteristics were obtained from governmental databases and literature on case studies. We found that many complex bars can be seen as simple elongated bars partly cut by mutually evasive ebb- and flood-dominated channels. Data analysis shows that bar dimensions scale with estuary dimensions, in particular estuary width. Breaking up the complex bars in simple bars greatly reduced scatter. Analytical bar theory overpredicts bar dimensions by an order of magnitude in case of small estuarine systems. Likewise, braiding index depends on local width-to-depth ratio, as was previously found for river systems. Our results suggest that estuary dimensions determine the order of magnitude of bar dimensions, while tidal characteristics modify this. We will continue to model bars numerically and experimentally. Our dataset on tidal bars enables future studies on the sedimentary architecture of geologically complex tidal deposits and enables studying effects of man-induced perturbations such as dredging and dumping on bar and channel patterns and habitats.

  5. Carbon dioxide and methane emissions from estuaries

    OpenAIRE

    Abril, G.; Borges, Alberto

    2005-01-01

    Carbon dioxide and methane emissions from estuaries are reviewed in relationwith biogeochemical processes and carbon cycling. In estuaries, carbondioxide and methane emissions show a large spatial and temporalvariability, which results from a complex interaction of river carbon inputs,sedimentation and resuspension processes, microbial processes in watersand sediments, tidal exchanges with marshes and flats and gas exchangewith the atmosphere. The net mineralization of land-derived organic ca...

  6. Tidal Heights in Hyper-Synchronous Estuaries

    OpenAIRE

    Ian M. Kidd; Shuhong Chai; Andrew Fischer

    2014-01-01

    Inconsistencies between datasets are examined with reference to flood tidal elevations in the Tamar River estuary, Tasmania Australia. Errors in a 30-year-old commonly cited dataset have been perpetuated in subsequent publications and datasets, and a clarification is herein provided. Elevation of the flood tidal wave as it propagates the estuary is evident in mean tide level and mean sea level, although the analysis is compromised by the temporal differences of the d...

  7. Estructura factorial del inventario multicultural de la depresión, estado-rasgo: Rol de las emociones positivas en la depresión

    OpenAIRE

    Manolete S. Moscoso; Cecile A. Lengacher; Melissa Knapp

    2012-01-01

    El propósito de este artículo fue presentar la construcción del inventario multicultural de la depresión, estado-rasgo (Imuder).Tomando en consideración el marco teórico de Susan Folkman acerca de la coexistencia de emociones positivas y negativas en el proceso de estrés severo y depresión, se procedió a la elaboración de ítems caracterizando estados y rasgos de emociones que expresan la presencia o ausencia de depresión. En base a una muestra multicultural con participantes de diversos paíse...

  8. Teoría de los rasgos: contribución a la teoría del comportamiento del empresario

    Directory of Open Access Journals (Sweden)

    Manuel Gutiérrez Roa

    1992-01-01

    Full Text Available El autor propone un nuevo punto de vista que relaciona la sicología con la Administración de Empresas. Se da una nueva explicación sobre el comportamiento del empresario mediante la formulación de hipótesis basadas en las teorías del comportamiento y en los hechos y actitudes que caracterizan al industrial en su actividad cotidiana. Las hipótesis son: - El empresario tiene una formación valorativa fruto de un proceso de interiorización y maduración del yo, a partir de una formación temprana en este sentido. - El conjunto de valores derivados de la anterior, determina en el individuo un conjunto de rasgos, que orientan su actuación y predominan en su personalidad. Un solo rasgo no tiene valor, es el conjunto el que interesa y explica su comportamiento.

  9. Psicologia do Ambiente

    OpenAIRE

    Antunes, Dalila; Bernardo, Fátima; Palma-Oliveira, José-Manuel

    2011-01-01

    Na aplicação da Psicologia à área do AMBIENTE importa em primeiro lugar definir o que se entende, neste contexto, por ambiente. O conceito é entendido como toda a envolvente que rodeia o ser humano. Referimo-nos pois ao espaço físico e aos estímulos que nele existem (som, ar, paisagem…), dirigindo-se a Psicologia do Ambiente ao estudo e intervenção sobre a forma como o ambiente influencia o indivíduo ou grupos, e sobre o modo como o comportamento dos indivíduos e grupos influenciam o ambiente...

  10. Diferencias en ansiedad estado-rasgo y en atención selectiva en Trastorno por Déficit de Atención con Hiperactividad (TDAH

    Directory of Open Access Journals (Sweden)

    Paloma González-Castro

    2015-01-01

    Full Text Available Uno de los trastornos que más afecta al rendimiento escolar es el Trastorno por Déficit de Atención con Hiperactividad (TDAH. El criterio establecido por el DSM diferencia tres subtipos: inatento, hiperactivo-impulsivo y combinado. Sin embargo, el perfil de este trastorno podría verse alterado por la asociación con otros como la ansiedad. El objetivo de esta investigación es determinar si hay diferentes patrones de atención (selectiva y sostenida y ansiedad (estado y rasgo en los tres subtipos de TDAH. Además, el objetivo es analizar cómo la ansiedad predice el rendimiento de los estudiantes con TDAH en una tarea de atención selectiva. La muestra estaba formada por 220 estudiantes (6-12 años: 56 en el grupo control, 54 con TDAH-Inatento, 53 con TDAH-Hiperactivo impulsivo y 56 con el subtipo combinado. Los resultados obtenidos mostraron que los cuatro grupos resultaban significativamente diferentes en las variables atencionales y en los niveles de ansiedad estado y rasgo. Al mismo tiempo, la ansiedad rasgo predijo el rendimiento en la variable de concentración analizada. Los resultados revelan un nuevo patrón de gran interés de cara a la evaluación diagnóstica objetiva y fiable en el TDAH.

  11. Atmosphere and Ambient Space

    DEFF Research Database (Denmark)

    Schmidt, Ulrik

    Atmosphere and Ambient Space This paper explores the relation between atmosphere and ambient space. Atmosphere and ambient space share many salient properties. They are both ontologically indeterminate, constantly varying and formally diffuse and they are both experienced as a subtle, non......-signifying property of a given space. But from a certain point of view, the two concepts also designate quite dissimilar experiences of space. To be ’ambient’ means to surround. Accordingly, ambient space is that space, which surrounds something or somebody. (Gibson 1987: 65) Since space is essentially...... of a surrounding character, all space can thus be described as having a fundamentally ambient character. So what precisely is an ambient space, then? As I will argue in my presentation, ambient space is a sensory effect of spatiality when a space is experienced as being particularly surrounding: a ‘space effect...

  12. Fitorremediación, una tecnología que involucra a plantas y microorganismos en el saneamiento ambiental

    OpenAIRE

    Jeannette Marrero-Coto; Isis Amores-Sánchez; Orquídea Coto-Pérez

    2012-01-01

    Uno de los rasgos distintivos de la sociedad moderna es la creciente generación de contaminantes ambientales, lo que trae consigo daños considerables a la salud humana y a la diversidad biológica. Los metales pesados son contaminantes que necesitan especial atención porque pueden permanecer varias décadas en el suelo y concentrarse en las cadenas tróficas. Las tecnologías desarrolladas para el saneamiento de ambientes contaminados con metales pesados son costosas y requieren un largo período ...

  13. Pasea: senderismo, cultura y naturaleza con Ecologistas en Acción. Una propuesta de Educación Ambiental

    OpenAIRE

    C. Lumbreras

    2005-01-01

    Pasea es un programa de educación ambiental, impulsado desde la asociación Ecologistas en Acción de Salamanca, bajo el formato de senderismo y convivencia con el fin de poner en valor los rasgos naturales y culturales de Salamanca, ayudado de los antiguos caminos, veredas, cordeles y calzadas, en visitas mensuales a cada una de las comarcas naturales, y bajo un clima amable de entretenimiento. En última instancia, y como base común a todas las salidas, cada paseo de Pasea está permit...

  14. The Design and Development of Online Course Materials: Some Features and Recommendations El diseño y desarrollo de materiales para cursos en línea: algunos rasgos y recomendaciones

    Directory of Open Access Journals (Sweden)

    Liliana Cuesta

    2010-04-01

    Full Text Available This article discusses various features in the design and implementation of online course materials. The author provides a critical review of some instructional design patterns and expands on the alignment among instruction, motivation and learners' performances as part of a curriculum design process. In this context, the author emphasizes the value of permanent analysis and assessment to support an efficient management of online environments in which knowledge construction and interaction find common ground on which to evolve. The author argues in favor of steady and competent efforts to implement varied educational strategies posed both for online instructors and learners. Practical recommendations are espoused for the designers of online courses.Este artículo discute distintos rasgos relacionados con el diseño y el uso de materiales en cursos virtuales. La autora ofrece una reseña crítica de algunos patrones del diseño instruccional y ahonda en la alineación existente entre instrucción, motivación y desempeño de los estudiantes como parte de un proceso de diseño curricular. En este contexto, la autora hace énfasis en el valor que tienen el análisis y la evaluación permanentes para apoyar el manejo eficiente de los ambientes virtuales en los que la construcción de conocimiento y la interacción encuentran un lugar común para su evolución. La autora defiende la idea de hacer esfuerzos constantes y competentes para usar distintas estrategias educativas, planteadas tanto para instructores virtuales como para sus estudiantes. Finalmente, se presentan recomendaciones practicas para los diseñadores de cursos virtuales.

  15. Otolith Sr concentration analyzed by PIXE in Ariake estuary-dependent sea bass juveniles

    International Nuclear Information System (INIS)

    Japanese sea bass (Lateolabrax japonicus) is a typical euryhaline marine fish and frequently migrates from salt to freshwater environments during early life stages. We hypothesized that strontium concentrations in the otolith could be a useful index to examine freshwater entry because of its lower concentration in freshwater. Otoliths of Japanese sea bass juveniles collected in the Chikugo river and estuary were analyzed by Particle Induced X-ray Emission (PIXE) to see relationship between strontium concentration and ambient salinity. Strontium concentrations in otoliths of sea bass juveniles are significantly lower in the river samples than in brackish water samples. (author)

  16. Estuary wader capacity following severe weather mortality

    International Nuclear Information System (INIS)

    The building of a tidal power barrage across an estuary may lead to substantial changes in its ecology. Many of Britain's estuaries hold internationally important numbers of waders. Careful consideration, therefore, needs to be given to the likely effects of tidal power barrages on wader populations. The opportunity for increased understanding of the mechanisms which govern wader populations was provided by a period of severe winter weather in 1991, which resulted in a substantial mortality of waders in eastern England. Such conditions are known to be stressful to birds and the study objectives were to investigate both the effects of and recovery from severe weather. (author)

  17. Rasgos de simplificación en el habla rural de dos localidades de Chile: descripción fonotáctica y discursiva

    Directory of Open Access Journals (Sweden)

    Miriam Elizabeth Cid Uribe

    2008-01-01

    Full Text Available El habla rural de Chile, variedad dialectal recurrente en alrededor del 14% de la población del país, según el último censo nacional, manifiesta rasgos particulares a nivel fonotáctico y discursivo que la caracterizan y la diferencian de otras variedades dialectales recurrentes en el país. Dentro de los aspectos fonotácticos se encuentran simplificaciones segméntales -elisiones, asimilaciones, sinalefas, sinéresis, sustituciones, entre otros- a las que se recurre con mayor o menor frecuencia; en el aspecto discursivo, la presencia y recurrencia de pausas llenas o vacías, las partidas falsas, las repeticiones, el alargamiento segmental se manifiestan en forma constante en esta variedad. En este artículo damos cuenta del comportamiento de los rasgos de simplificación en el habla rural de dos localidades de la Región Metropolitana desde el punto de vista de la manifestación fonotáctica de cada uno de estos rasgos en la elaboración de su discurso semiespontáneo.Chilean rural speech, variety spoken by nearly 14% of the population of the country according to the latest national census, shows specfñcphonotactic and discourse fea-tures which characterise and differentiate itfrom other dialectal varieties found in the country. Segmental simplfñcations like elisión, assimilation, gradation, compression, substitution,amongstothers,are tobe found as recurrentfeaturesat the phonotactic level; at the discourse level, phenomena like pauses -filled or empty-, false starts, repetitions, segmental lengthening are recurrent in this variety. In this article we give an account of the behaviour of such fea tures as they are manifested -phonotactically and discoursally- in two rural communities of the Metropolitan Región at the moment of producing semi spontaneous speech.

  18. Estuary fish data - Juvenile salmon in migratory corridors of lower Columbia River estuary

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Sampling juvenile salmon and associated fishes in open waters of the lower Columbia River estuary. Field work includes bi-weekly sampling during the spring...

  19. PECONIC ESTUARY: AN ASSESSMENT OF SHELLFISH RESOURCES IN THE TRIBUTARIES AND EMBAYMENTS OF THE PECONIC ESTUARY

    Science.gov (United States)

    Executive Summary Historically, the Peconic Estuary's shellfish resources have supported significant fisheries for a number of species including hard clams, oysters and bay scallops. However, distribution and abundance data for the tributaries and embayments within the Peconic Es...

  20. Diferencias en ansiedad estado-rasgo y en atención selectiva en Trastorno por Déficit de Atención con Hiperactividad (TDAH)

    OpenAIRE

    Paloma González-Castro; Celestino Rodríguez; Marisol Cueli; Trinidad García; David Álvarez

    2015-01-01

    Uno de los trastornos que más afecta al rendimiento escolar es el Trastorno por Déficit de Atención con Hiperactividad (TDAH). El criterio establecido por el DSM diferencia tres subtipos: inatento, hiperactivo-impulsivo y combinado. Sin embargo, el perfil de este trastorno podría verse alterado por la asociación con otros como la ansiedad. El objetivo de esta investigación es determinar si hay diferentes patrones de atención (selectiva y sostenida) y ansiedad (estado y rasgo) en los tr...

  1. La inteligencia emocional rasgo, la autoeficacia para el liderazgo y su vinculación a procesos afectivos grupales, cognitivos y de desempeño

    OpenAIRE

    Villanueva Sierra, José Juan

    2008-01-01

    El presente estudio explora el papel de la inteligencia emocional rasgo y la autoeficacia para el liderazgo sobre determinados procesos grupales tanto afectivos como cognitivos. A su vez se analiza la repercusión de dichas dinámicas en el rendimiento grupal al llevar a cabo una tarea compleja.La muestra estuvo constituida por 176 estudiantes universitarios, con un promedio de edad de 22 años (17% varones y 83% mujeres). Dichos estudiantes participaron de forma voluntaria en un experimento qu...

  2. Detección de rasgos en imágenes con ruido: Una aproximación con funciones LISA en procesos puntuales espaciales

    OpenAIRE

    Lorenzo Valentín, Gil

    2005-01-01

    En esta tesis doctoral se retoma un problema de interés real, como es la detección de agrupaciones de puntos -que denominamos rasgos- en imágenes digitalizadas, que se encuentran en compañía de otros puntos que no son de interés, a estos los denominamos ruido. Se pretende separar y clasificar. Las últimas aportaciones hechas en este campo, se dirigen a considerar ausencia de modelo de probabilidad que originó la distribución espacial de los puntos en la imagen, utilizándose distancias al k-és...

  3. Loci de rasgos binarios que influyen en la expresión del comportamiento higiénico de las abejas melíferas

    OpenAIRE

    Arechavaleta-Velasco, Miguel E.; Hunt, Greg J.; Marla Spivak; Carmen Camacho-Rea

    2011-01-01

    Este estudio se realizó para detectar loci de rasgos binarios (BTL) que influyen en la expresión del comportamiento higiénico de abejas obreras y para localizar marcadores genéticos asociados a estos BTL en un mapa de ligamiento. Se recolectaron abejas que realizaron el comportamiento higiénico y abejas que no realizaron el comportamiento higiénico de una colonia producto de una retrocruza. Se construyó un mapa genético utilizando marcadores AFLP generados a partir del ADN de las abejas que r...

  4. Descripción de los rasgos de personalidad y las características neuropsicológicas en excombatientes del conflicto armado colombiano

    OpenAIRE

    Bettin Osorio, Miguel

    2016-01-01

    La presente investigación establece, correlaciona y describe en 46 sujetos (25 Guerrilleros y 21 Paramilitares); el Grado de Filiación Ideológica a la organización armada ilegal de la guerra civil colombiana a la que pertenecieron, y por ende, a su participación en los crímenes particularmente violentos, de tipo depredador, frío, psicopático, cometidos por la misma, así como a los Déficits Neuropsicológicos, los Rasgos Psicopáticos, las Formas de Razonamiento Moral y las Características Psico...

  5. Features at some significant estuaries of India

    Digital Repository Service at National Institute of Oceanography (India)

    Bhattathiri, P.M.A.

    in the second and 162 in the third. Most of the studies on various aspects have been confined to very few of these, and that too, mostly to minor ones. Very little work has been carried out from many of the estuaries of the major rivers. An overview...

  6. Radiological assessment of the Esk Estuary

    International Nuclear Information System (INIS)

    An assessment has been carried out of the radiological impact of artificial radionuclides in the Esk estuary in Cumbria, UK. Measurements were made of the distributions of 137Cs, 239+240Pu, and 241Am in water, surface bed sediments and core profiles. The highest measured concentrations in surface sediments were 2.8 Bq g-1 of 137Cs, 3.1 Bq g-1 of 239+240Pu and 4.7 Bq g-1 of 241Am. These values represent significant decreases from similar measurements made in 1970-1980. The measured behaviour of the actinides in low salinity water at the head of the estuary supports previous observations of actinide remobilisation from the bed. A model has been developed which simulates the long-term behaviour of radioactivity in the estuary. The model incorporates representations of tidal mixing, sediment transport, seasonal and long-term sediment accretion. The model also represents long-term build-up in salt marsh regions. The model gives good agreement with measured distributions of 137Cs, but tends to underestimate actinide concentrations by factors of 2-3. Dose calculations show the importance of radionuclide uptake through livestock grazing sea-washed pasture alongside the estuary. 137Cs and 241Am are identified as the most important radionuclides considered in the assessment. (Author)

  7. Bacterioplankton dynamics in the Mondego estuary (Portugal)

    Science.gov (United States)

    Bacelar-Nicolau, P.; Nicolau, L. B.; Marques, J. C.; Morgado, F.; Pastorinho, R.; Azeiteiro, U. M.

    2003-05-01

    In this work, the density of bacterioplankton and environmental parameters were monitored over a 11 month period (July 1999-June 2000), and also during one tidal cycle (15 June 2000), at two sampling stations, in the estuary of River Mondego. These data were treated by multivariate analyses methods in order to identify the key factors that control the dynamics of the bacterioplankton in the estuary. Bacterial dynamics were dominated by temporal gradients (annual seasons and tide-related) and less by the spatial structure of the estuary. Three main metabolic groups of bacterioplankton—aerobic heterotrophic bacteria, sulphate-reducing bacteria (SRB) and nitrate-reducing bacteria (NRB)—involved in the cycling of organic matter, were present in the water column of the estuary. Their relative abundance depended on the particular physical, chemical and biological environment. The abundance of aerobic heterotrophic bacteria, during the 11 month study, was modelled as a function of nitrate (the most important variable, with a negative effect), temperature, salinity and pH (with positive effects). SRB appeared to be limited to the water-sediment interface, where concentrations of sulphate and POM were greater. A competition between SRB and NRB for carbon has also been suggested.

  8. Reversing circulation patterns in a tropical estuary

    Science.gov (United States)

    Valle-Levinson, Arnoldo; Bosley, Kathryn T.

    2003-10-01

    A combination of current velocity and water density measurements was used to characterize the basic patterns of water exchange in the Gulf of Fonseca, a tropical estuary on the Pacific Ocean side of Central America. The measurements were obtained during spring and neap tides in March (dry season) and June (wet season) of 2001 and consisted of profiles of current velocity and density along four transects. From mid-March to mid-April a time series of hourly surface current velocity maps was also obtained with a high-frequency radar system of two antennas. The sampling transects and the radar coverage concentrated in the portion of the estuary that has open communication with the ocean. During the dry season, water exchange at the entrance to the gulf suggested an inverse estuarine circulation that was more robust, and its dynamics were closer to geostrophy during neap than during spring tides. It is likely that salinity increased toward the tributaries of the system and then decreased within those tributaries because of the persistent influence of fresh water. In contrast, during the wet season, salinity decreased into the estuary, and the circulation resembled that of a typical estuary. In this season the fortnightly modulation of exchange flows was masked by wind effects, which also played a relevant role in the dynamics. The net volume inflows measured in both seasons suggested that the residence time of the Gulf of Fonseca varies from 2 weeks to 1 month.

  9. BCG Approaches for Improved Management of Estuaries

    Science.gov (United States)

    Estuaries and other complex aquatic systems are exposed to a variety of stressors that act at several scales, but are managed piecemeal - - often resulting in a “death by 1000 cuts” caused by cumulative impacts to these valued resources. To address this, managers need tools that...

  10. Distribution of foraminifera in the Cochin estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, K.K.; Balasubramanian, T.

    of the channel by dredging. It is also predicted that total number of species present in the estuary will likely increase further as more nearshore foraminiferids migrate into it in the coming years, with more deepening of the channel as it will enhance speed...

  11. Nutrient elements in large Chinese estuaries

    Science.gov (United States)

    Zhang, Jing

    1996-07-01

    Based on comprehensive observations since 1983, this study summarizes major features of nutrient elements (nitrogen, phosphorus and silicon) in large Chinese river/estuary systems. Elevated nutrient element levels were observed in Chinese rivers, when compared to large and less disturbed aquatic systems (e.g. the Amazon, Zaire and Orinoco). Data from this study are similar to those obtained from the polluted and/or eutrophic rivers in Europe and North America (e.g. the Rhóne and Loire). Nutrient elements may have either conservative or active distributions, or both, in the mixing zone, depending on the element and the estuary. For example, non-conservative behaviors were observed in the upper estuary, where nutrient elements may be remobilized due to the strong desorption and variations of the fresh water end-member, but conservative distributions were found afterwards in the lower estuary. Outside the riverine effluent plumes, nutrient elements may be depleted in surface waters relative to elevated bioproduction, whereas the regeneration with respect to decomposition of organic material and/or nitrification/denitrification offshore, may sustain high levels of nutrient elements in near-bottom waters. Laboratory experiment data generally compares well with field observations. The high fluxes and area] yields of nutrient elements from large Chinese rivers, indicate the extensive use of chemical fertilizers and domestic waste drainage over watersheds in China.

  12. Species-specific variation in the phosphorus nutritional sources by microphytoplankton in a Mediterranean estuary

    Directory of Open Access Journals (Sweden)

    MARLY CAROLINA MARTINEZ SOTO

    2015-08-01

    Full Text Available We investigated the species-specific phosphorus (P nutrition sources in the microphytoplankton community in the Mahon estuary (Minorca, Western Mediterranean in 2011, under two contrasting hydrographic scenarios. Estuarine flow, nutrient concentrations, phytoplankton community composition and enzyme-labeled fluorescence (ELF were measured in June and October, corresponding to the beginning and the end of summer. Dissolved inorganic nitrogen (DIN and inorganic phosphate (Pi exhibited enhanced concentrations in the inner estuary where N:P molar ratios suggested P-limitation in both surveys. Pi was low and variable (0.09±0.02 μmol•l-1 in June and 0.06±0.02 μmol•l-1 in October, whereas organic phosphorus remained a more reliable P source. Even though ambient Pi concentrations were slightly higher on June, when the microphytoplankton assemblage was dominated by dinoflagellates, the percentage of cells expressing ELF labeling was notably higher (65% of total cells than in October (12%, when the presence of diatoms characterized the microphytoplankton community. ELF was mainly expressed by dinoflagellate taxa, whereas diatoms only expressed significant AP in the inner estuary during the June survey. A P-addition bioassay in which response of AP to Pi enrichment was evaluated showed remarkable reduction in AP with increasing Pi. However, some dinoflagellate species maintained AP even when Pi was supplied in excess. We suggest that in the case of some dinoflagellate species AP is not as tightly controlled by ambient Pi as previously believed. AP activity in these species could indicate selective use of organic phosphorus, or slow metabolic response to changes in P forms, rather than physiological stress to low Pi availability. We emphasize the importance of identifying the links between the different P sources and the species-specific requirements, in order to understand the ecological response to anthropogenic biogeochemical perturbations.

  13. Nutrient budgets for large Chinese estuaries

    Directory of Open Access Journals (Sweden)

    S. M. Liu

    2009-10-01

    Full Text Available Chinese rivers deliver about 5–10% of global freshwater input and 15–20% of the global continental sediment to the world ocean. We report the riverine fluxes and concentrations of major nutrients (nitrogen, phosphorus, and silicon in the rivers of the contiguous landmass of China and Korea in the northeast Asia. The rivers are generally enriched with dissolved inorganic nitrogen (DIN and depleted in dissolved inorganic phosphate (PO43− with very high DIN: PO43− concentration ratios. DIN, phosphorus, and silicon levels and loads in rivers are mainly affected by agriculture activities and urbanization, anthropogenic activities and adsorption on particulates, and rock types, climate and physical denudation intensity, respectively. Nutrient transports by rivers in the summer are 3–4 times higher than those in the winter with the exception of NH4+. The flux of NH4+ is rather constant throughout the year due to the anthropogenic sources such as the sewer discharge. As nutrient composition has changed in the rivers, ecosystems in estuaries and coastal sea have also changed in recent decades. Among the changes, a shift of limiting nutrients from phosphorus to nitrogen for phytoplankton production with urbanization is noticeable and in some areas silicon becomes the limiting nutrient for diatom productivity. A simple steady-state mass-balance box model was employed to assess nutrient budgets in the estuaries. The major Chinese estuaries export <15% of nitrogen, <6% of phosphorus required for phytoplankton production and ~4% of silicon required for diatom growth in the Chinese Seas (Bohai, Yellow Sea, East China Sea, South China Sea. This suggests that land-derived nutrients are largely confined to the immediate estuaries, and ecosystem in the coastal sea beyond the estuaries is mainly supported by other nutrient sources such as regeneration, open ocean and

  14. Análisis factorial exploratorio del Inventario de Depresión Estado-Rasgo (ST-DEP en adolescentes

    Directory of Open Access Journals (Sweden)

    César Merino Soto

    2012-01-01

    Full Text Available El Inventario de Depresión Estado-Rasgo (IDER evalúa de forma breve distintos síntomas depresivos. El objetivo es evaluar algunas propiedades psicométricas del IDER en Perú. La muestra estuvo formada por 314 estudiantes entre 11 y 18 años de secundaria en un colegio limeño. Los resultados indican una estructura bidimensional –que corresponde con la delimitación conceptual del inventario original–. Sin embargo, algunos ítems presentaron cargas comparativamente bajas, probablemente debido a variaciones culturales. Adicionalmente, la consistencia interna para la dimensión de Estado y Rasgo presentó valores alfa de Cronbach de 0.76 y 0.68, respectivamente. El cuestionario IDER satisface el criterio de invariabilidad de la estructura interna y puede dar una alternativa favorable para el diagnóstico y evaluación de la depresión en adolescentes peruanos.

  15. Mesozooplankton affinities in a recovering freshwater estuary

    Science.gov (United States)

    Chambord, Sophie; Maris, Tom; Colas, Fanny; Van Engeland, Tom; Sossou, Akoko-C.; Azémar, Frédéric; Le Coz, Maïwen; Cox, Tom; Buisson, Laetitia; Souissi, Sami; Meire, Patrick; Tackx, Michèle

    2016-08-01

    Water quality of the Scheldt estuary (Belgium/The Netherlands) has considerably improved in recent years, especially in the upstream, freshwater reaches. Within the zooplankton community, the copepod Eurytemora affinis, typically abundant in brackish water and quasi-absent from freshwater before 2007, has since substantially developed in the latter, where it now represents 90% of the crustacean mesozooplankton community. Simultaneously, cyclopoid copepod abundance has greatly decreased, while cladoceran abundance did not change. The study aim was: 1) to verify if the zooplankton community described for the period 2007-2009 by Mialet et al. (2011) has stabilized until present, and 2) to look for the environmental conditions favouring E. affinis development and causing changes in the upstream freshwater zooplankton community. The 2002-2012 temporal evolution of the zooplankton distribution at three stations in the upstream freshwater Scheldt estuary was analyzed. Water quality remained better after 2007 than before, and some factors revealed continuous improvement in annual mean concentrations (e.g. increase in O2, decrease in BOD5 and NH4sbnd N concentration). The increase in oxygen and the decrease in NH4sbnd N concentration, together with low discharge during summer were the main environmental factors explaining the development and timing of E. affinis in the upstream freshwater reach. In this reach, E. affinis maximal abundance is shifted to higher temperatures (summer) compared to its typical maximum spring abundance peak in the brackish zone of the Scheldt estuary and in most temperate estuaries. The changes in zooplankton community followed a temporal and spatial gradient induced by the spatio-temporal evolution of water quality improvement. The most downstream station (3) allowed E. affinis development (oxygen concentration > 4 mg L-1; NH4sbnd N concentration oxygen, etc.), there is no clear cause for their decline. Water quality improvement in the freshwater

  16. A sensitivity analysis of low salinity habitats simulated by a hydrodynamic model in the Manatee River estuary in Florida, USA

    Science.gov (United States)

    Chen, XinJian

    2012-06-01

    This paper presents a sensitivity study of simulated availability of low salinity habitats by a hydrodynamic model for the Manatee River estuary located in the southwest portion of the Florida peninsula. The purpose of the modeling study was to establish a regulatory minimum freshwater flow rate required to prevent the estuarine ecosystem from significant harm. The model used in the study was a multi-block model that dynamically couples a three-dimensional (3D) hydrodynamic model with a laterally averaged (2DV) hydrodynamic model. The model was calibrated and verified against measured real-time data of surface elevation and salinity at five stations during March 2005-July 2006. The calibrated model was then used to conduct a series of scenario runs to investigate effects of the flow reduction on salinity distributions in the Manatee River estuary. Based on simulated salinity distribution in the estuary, water volumes, bottom areas and shoreline lengths for salinity less than certain predefined values were calculated and analyzed to help establish the minimum freshwater flow rate for the estuarine system. The sensitivity analysis conducted during the modeling study for the Manatee River estuary examined effects of the bottom roughness, ambient vertical eddy viscosity/diffusivity, horizontal eddy viscosity/diffusivity, and ungauged flow on the model results and identified the relative importance of these model parameters (input data) to the outcome of the availability of low salinity habitats. It is found that the ambient vertical eddy viscosity/diffusivity is the most influential factor controlling the model outcome, while the horizontal eddy viscosity/diffusivity is the least influential one.

  17. Seasonal stratification and property distributions in a tropical estuary (Cochin estuary, west coast, India)

    Science.gov (United States)

    Shivaprasad, A.; Vinita, J.; Revichandran, C.; Reny, P. D.; Deepak, M. P.; Muraleedharan, K. R.; Naveen Kumar, K. R.

    2013-01-01

    The intratidal, spring-neap and seasonal variations in stratification were examined in the Cochin estuary. The observations established a strong connection with the distribution of chemical and biological properties. The influence of tides and river discharge forcing in water column stability was quantified using potential energy anomaly (PEA) and stratification parameter. Partially mixed (neap) and well-mixed (spring) conditions during low river discharge (dry) period were altered in monsoon by the salt wedge intrusions. The ecological impact of salt wedge propagation on high tides bringing upwelled water to the system was evident from the bottom hypoxic, high chlorophyll a and nutrient-rich conditions. Phosphate and nitrite concentrations were higher at the bottom saline conditions but silicate and nitrate were clearly supplied by river water. However, during ebb tide this front was driven out of the estuary. The periodic advance and retreat of the salt wedge was inevitable in making the system immune from extended hypoxia/anoxia and maintaining the health of the Cochin estuary. For the seasonally varying river flow in the estuary, salt intrusion receded with increasing river flow in monsoon and rebounded with decreasing river flow in dry season. During monsoon, the intense flushing and reduction in salinity field expansion seemed to be responsible for the limited chlorophyll a levels along the surface of the Cochin estuary.

  18. Seasonal stratification and property distributions in a tropical estuary (Cochin estuary, west coast, India

    Directory of Open Access Journals (Sweden)

    A. Shivaprasad

    2012-07-01

    Full Text Available The intratidal, spring-neap and seasonal variations in stratification were examined in Cochin estuary. The observations established a strong connection with the distribution of chemical and biological properties. The influence of tides and river discharge forcing in water column stability was quantified using potential energy anomaly (PEA and stratification parameter. Partially mixed (neap and well-mixed (spring conditions during low river discharge (dry period were altered in monsoon by the salt wedge intrusions. The ecological impact of salt wedge propagation on high tides bringing upwelled water to the system was evident from the bottom hypoxic, high chlorophyll a and nutrient-rich conditions. Phosphate and nitrite concentrations were higher at the bottom saline conditions but silicate and nitrate were clearly supplied by river water. However, during ebb tide this front was driven out of the estuary. The periodic advance and retreat of the salt wedge was inevitable in making the system immune from extended hypoxia/anoxia and maintaining the health of Cochin estuary. For the seasonally varying river flow in the estuary, salt intrusion receded with increasing river flow in monsoon and rebounded with decreasing river flow in dry season. During monsoon, the intense flushing and reduction in salinity field expansion seemed to be responsible for the limited chlorophyll a levels along the surface of Cochin estuary.

  19. A predictive model for salt intrusion in estuaries applied to the Yangtze estuary

    Science.gov (United States)

    Cai, Huayang; Savenije, Hubert H. G.; Zuo, Shuhua; Jiang, Chenjuan; Chua, Vivien P.

    2015-10-01

    Understanding the way salinity distribution in an estuary reacts to external drivers (e.g., tide, fresh water discharge, dredging, etc.) is important for both water quality and water resources management in estuaries. The salinity distribution depends strongly on the geometry of an estuary, but also on the fresh water discharge that counteracts the salt intrusion. In estuaries it is notoriously hard to estimate this discharge and subsequently to predict the parameters that determine the mixing behaviour depending on it. Recently a method has been developed to predict the fresh water discharge on the basis of water level observations. In addition, predictive equations for tidal mixing have been updated and revised. In this paper, these two predictive methods are combined and subsequently applied to the Yangtze estuary under a wide variation of fresh water discharge. The predicted salt distribution appears to be in good agreement with observations. To provide insight into the optimum use of water resources (e.g., to determine the amount of fresh water discharge required to maintain a specific salt intrusion length), we further study the salt intrusion pattern under different tide and fresh water discharge conditions.

  20. The ecological condition of estuaries in the Gulf of Mexico

    OpenAIRE

    1999-01-01

    This document is intended for use by scientists and other citizens concerned with the ecological condition of estuaries, as well as by managers and lawmakers interested in the sustained use of estuaries for commercial and recreational purposes. It also addresses public concerns about the aesthetic quality of coastal areas vital to tourism and recreation. By producing this report on the ecological condition of estuaries in the Gulf of Mexico, we have taken one step in assessing the health of t...

  1. Marine geology of the St. Lawrence Estuary

    Energy Technology Data Exchange (ETDEWEB)

    St-Onge, Guillaume [Canada Research Chair in Marine Geology, Institut des sciences de la mer de Rimouski (ISMER) and GEOTOP Research Center, 310 allee des Ursulines, Rimouski, Quebec, G5L 3A1 (Canada); Duchesne, Mathieu J [Geological Survey of Canada, Quebec Division, 490 de la Couronne, Quebec City, Quebec, G1K 9A9 (Canada); Lajeunesse, Patrick, E-mail: guillaume_st-onge@uqar.qc.ca [Departement de geographie and Centre d' etudes nordiques, Universite Laval, Quebec City, Quebec, G1V 0A6 (Canada)

    2011-05-15

    The St. Lawrence Estuary, Eastern Canada, contains a very thick (>450 m) Quaternary sedimentary sequence. The results from recently conducted geophysical surveys in conjunction with piston coring indicate that these sediments were deposited under very high sedimentation rates, sometimes as high as {approx}30 m/ka during the last deglaciation. Results also reveal evidence of large submarine landslides during the Holocene, changes in sedimentation rates and the significant role of submarine canyons and channels to transfer sediments from the coast to the deeper marine environment. Finally, this paper highlights the presence of more than 1900 pockmarks on the seafloor of the St. Lawrence Estuary and discusses their possible origins: active hydrocarbon seeps in the Laurentian Channel and biogenic gas seepage on the northwestern shoulder of the Laurentian Channel.

  2. Time-dependence of salinity in monsoonal estuaries

    Digital Repository Service at National Institute of Oceanography (India)

    Vijith, V.; Sundar, D.; Shetye, S.R.

    ) Based on data during 1970- 1979 Ria of Ferrol, Spain (north-east coast) 250 14.5 6.0 de Castro et al. (2004) Based on data during 1970- 1982 Hudson River estuary, U.S.A. (east coast) 1925* 877.3 376.7 Ralston et al. (2008), Moran and Limburg (1986.... We refer to such estuaries as “monsoonal estuaries” following earlier usage (see, for example, 3 Khadkikar, 2008). To make a case for essential unsteadiness of the salinity field in a monsoonal estuary, we use the Mandovi estuary on the west...

  3. Phosphorous dynamics in a temperate intertidal estuary

    OpenAIRE

    Lillebø, A. I.; Neto, J. M.; Flindt, M. R.; Marques, J C; Pardal, M.A.

    2004-01-01

    Conservation and management of aquatic systems require detailed information of the processes that affect their functioning and development. The objectives of the present work were to describe the phosphorus dynamics during a complete tidal cycle and to quantify the relative contribution of the most common estuarine areas (e.g. seagrass beds, salt marshes, mud- and sand-flats without vegetation) to phosphorus net internal loading in a temperate intertidal estuary.

  4. Impact of climate change on Gironde estuary

    International Nuclear Information System (INIS)

    Within the THESEUS European project, a simplified mathematical model for storm surge levels in the Bay of Biscay was adjusted on 10 events at Le Verdon using wind and pressure fields from CLM/SGA, so that the water levels at Le Verdon have the same statistic quantiles as observed tide records for the period [1960-2000]. A numerical model of the Gironde Estuary was used to evaluate future water levels at 6 locations of the estuary from Le Verdon to Bordeaux and to assess the changes in the quantiles of water levels during the 21. century using ONERC's pessimistic scenario for sea level rise (60 cm). The analysis of future storm surge levels shows a decrease in their quantiles at Le Verdon,, whereas there is an increase of the quantiles of total water levels. This increase is smaller than the sea level rise and gets even smaller as one enters farther upstream in the estuary. A series of flood maps for different return periods between 2 and 100 years and for four time periods ([1960-1999], [2010-2039], [2040-2069] and [2070-2099]) have been built for the region of Bordeaux. Quantiles of water levels in the flood plain have also been calculated. The impact of climate change on the evolution of flooded areas in the Gironde Estuary and on quantiles of water levels in the flood plain mainly depends on the sea level rise. Areas which are not currently flooded for low return periods will be inundated in 2100. The influence of river discharges and dike breaching should also be taken into account for more accurate results. (authors)

  5. An investigation of ambient gameplay

    OpenAIRE

    Eyles, Mark

    2012-01-01

    Inspired by Brian Eno's ambient music, which is persistent and supports different levels of engagement, this research explores ambient gameplay in computer, video and pervasive games. Through the creation of original games containing ambient gameplay and looking for ambient gameplay in existing commercial games, this research focuses on gameplay that supports a range of depths of player engagement. This research is not concerned with ambient intelligent environments or other technologies that...

  6. Ambient oxygen promotes tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Ho Joong Sung

    Full Text Available Oxygen serves as an essential factor for oxidative stress, and it has been shown to be a mutagen in bacteria. While it is well established that ambient oxygen can also cause genomic instability in cultured mammalian cells, its effect on de novo tumorigenesis at the organismal level is unclear. Herein, by decreasing ambient oxygen exposure, we report a ∼50% increase in the median tumor-free survival time of p53-/- mice. In the thymus, reducing oxygen exposure decreased the levels of oxidative DNA damage and RAG recombinase, both of which are known to promote lymphomagenesis in p53-/- mice. Oxygen is further shown to be associated with genomic instability in two additional cancer models involving the APC tumor suppressor gene and chemical carcinogenesis. Together, these observations represent the first report directly testing the effect of ambient oxygen on de novo tumorigenesis and provide important physiologic evidence demonstrating its critical role in increasing genomic instability in vivo.

  7. Rasgos morfosedimentarios, procesos y evolución de la plataforma continental Argentina desde el último máximo glacial

    Directory of Open Access Journals (Sweden)

    Roberto A Violante

    2014-06-01

    Full Text Available La plataforma continental argentina es una de las plataformas submarinas más extensas del mundo, localizada en un contexto geotectónico dominado por un margen continental pasivo, aunque en su porción más austral se asocia a sectores de márgenes activos. Su extensión y escaso relieve han favorecido un profundo efecto modelador producto de las sucesivas transgresiones y regresiones marinas del Cuaternario, que le imprimieron variados rasgos morfosedimentarios. La transgresión postglacial dejó los rasgos finales que pueden ser reconocidos en las características superficiales y subsuperficiales, como ser las terrazas escalonadas asociadas a variaciones en la velocidad de ascenso del nivel del mar así como evidencias de paleolíneas de costas hoy sumergidas. Numerosos rasgos demuestran aspectos de la exposición subaérea durante el Último Máximo Glacial, como relictos de redes fluviales, depósitos glacifluviales y remanentes de suelos. La acción conjunta de los procesos actuantes favoreció la redistribución de los sedimentos aportados por la erosión de las sucesivas líneas de costas durante los avances y retrocesos marinos, además de aquellos incorporados desde el continente por acción eólica y fluvial. De esta manera, la cobertura sedimentaria resultante es terrígena de tipo relíctico y palimpséstico. Las características del borde exterior de la plataforma en transición al talud demuestran complejos procesos tanto litorales (durante etapas de bajo nivel del mar como profundos (erosión retrocederte asociada a la dinámica de cañones submarinos, mientras que la disposición diferente de las terrazas entre los sectores bonaerense y patagónico de la plataforma estaría asociada a ajustes hidroisostáticos.

  8. Columbia River Estuary Ecosystem Classification Cultural Features

    Science.gov (United States)

    Cannon, Charles M.; Ramirez, Mary F.; Burke, Jennifer L.; Simenstad, Charles A.; O'Connor, Jim E.; Marcoe, Keith

    2012-01-01

    Estuarine ecosystems are controlled by a variety of processes that operate at multiple spatial and temporal scales. Understanding the hierarchical nature of these processes will aid in prioritization of restoration efforts. This hierarchical Columbia River Estuary Ecosystem Classification (henceforth "Classification") of the Columbia River estuary is a spatial database of the tidally-influenced reaches of the lower Columbia River, the tidally affected parts of its tributaries, and the landforms that make up their floodplains for the 230 kilometers between the Pacific Ocean and Bonneville Dam. This work is a collaborative effort between University of Washington School of Aquatic and Fishery Sciences (henceforth "UW"), U.S. Geological Survey (henceforth "USGS"), and the Lower Columbia Estuary Partnership (henceforth "EP"). Consideration of geomorphologic processes will improve the understanding of controlling physical factors that drive ecosystem evolution along the tidal Columbia River. The mapping extent is the interpreted Holocene geologic floodplain of the tidal Columbia River and its tributaries to the estimated head of tide. Cultural features within the Holocene floodplain were mapped by visual interpretation of Light Detection and Ranging (LiDAR) topography supplemented with aerial photographs and U.S. Geological Survey topographic maps. Mapped cultural features are classified as to their purpose when constructed. Because features were drawn based on LiDAR topography, only features with a significant topographic expression are mapped.

  9. Mujer y medio ambiente

    OpenAIRE

    Zuluaga Sánchez, Gloria Patricia

    1998-01-01

    El debate sobre mujer y medio ambiente es bastante nuevo y, por lo tanto, aun no hay consenso sobre como abordarlo, ni análisis muy profundos sobre la interacción de estas dos problemáticas tan complejas y que además atraviesan las demás temáticas. Con ello no se quiere negar el importante aporte que se ha hecho en tal sentido, por parte de colectividades y de algunas personas. Selene Herculano y Jacqueline Pitanguy (1993), mencionan que el medio ambiente no es una categoría específica y que ...

  10. Ambientes de aprendizaje computacionales

    OpenAIRE

    Señas, Perla

    2001-01-01

    En el marco de las aplicaciones de la tecnología computacional a la educación se destaca de manera especial el trabajo sobre Ambientes de Aprendizaje. En él convergen tópicos relevantes de las Ciencias de la Computación y de la Educación. Se puede definir un Ambiente de Aprendizaje Computacional como un entorno integrado por un conjunto no homogéneo de elementos capaces de crear o recrear situaciones a partir de las cuales el alumno puede construir conocimiento y realizar aprendizajes y meta-...

  11. "Coeficientes de herencia, correlaciones, repetibilidad e índice de selección de rasgos reproductivos en porcinos"

    Directory of Open Access Journals (Sweden)

    Arango B. Humherto

    1989-12-01

    fueron: a Hermanos medios: PN =0.38, P 21 = 0.23, PD.=0.41, NN =0.23, N21 =0.17, ND=tl.27, 121 = 1.54,156=0.38, PCN =0.75,PC21 = 0.13, PCD =0.41 (PC = peso de la camada. b Por, regresión: PN=0.21, P21 =0.33, PD=0.23, NN =0.32, N21= 0.19, ND=0.39, 121 =0.53,1-56=0.41. Las correlaciones genéticas y fenotípicas calculadas se pueden considerar entre bajas y medias, con algunas de sentido opuesto. Las repetibilidades resultaron altas, por ser las h2 altas. Los índices calculados involucraron dos y tres variables (PN, PD e 156 días. 1a=37 X 1 + 1633 X2 + 22209Xs Ib = 0.34 Xl + 18 X2. El avance genético resultan1e de la aplicación del índice para dos variables fue de 5.3 % mayor para peso al nacer y 342 % para peso al destete. Para el de tres variables fue de 34 % para peso al nacer y 419 % para peso al destete y 311 para incremento de peso  más que el avance por selección de rasgos individuales.

  12. Current Characterization at the Amazon estuary

    Science.gov (United States)

    Bezerra, M. O.

    2009-04-01

    At the estuary there are several mechanisms that cause turbulence: influence of solid contours (estuary bottom and shores), speed vertical shearing (fluid inside), wind shearing stress (free surface) and surface and internal gravity waves. Turbulence intensity controls vertical distribution of estuary water mass property concentration. As flow into the estuary takes place during the transition or turbulent regimen, produced by small space and time scale movements, entrainment, turbulent scattering and advection are the processes responsible for fresh water mixing up with the sea and for local salinity variation, as well as for concentration of natural properties and man-made ones. According to this focus, we shall describe general circulation, conveyance and mixing characteristics of the Amazon low estuary waters. Amazon estuary shows unusual characteristics: it is of vast length and enormous outflow. It is extremely wide - 150 Km - and its discharge into the Atlantic amounts to 180,000 m3s-1 (Otman, 1968, Figueiredo et al, 1991), which means 18% of all water discharged by rivers into oceans; this is the largest punctual source of fresh water for oceans (Milliman and Meade, 1983). Maximum outflow is 2.5 x 105 m3s-1, and it happens at the end of May. Minimum outflow is 1.2 x 105 m3 s-1, and it takes place in November. At Amazon River, the Mixing Zone occurs where the Coastal Zone usually is. The reason for that is the extension of fresh water plume moves Northeast for over 1000 Km (Gibbs, 1970; Muller-Karger et al 1988). This is the most extensive estuarine plume ever found in the ocean. During low fluvial discharge (June-November) plume reaches 300 Km; however, on high discharge (November-May) plume reaches 500 Km. Plume already is 3 to 10 m thick and 80 to 300 Km wide (Lentz and Limeburner, 1995). From June to January plume moves towards Africa, from whence 70% of it goes east carried by North Brazil Current retroflection and 30% goes towards the Caribbean. From

  13. El proceso de la apropiación: un rasgo distintivo en la educación energética

    Directory of Open Access Journals (Sweden)

    Ernesto Ramón Ávila-Guerra

    2012-01-01

    Full Text Available Al proponer la conceptualización de la Educación Energética para el Desarrollo Sostenible, se destacó como un rasgo esencial el proceso de apropiación del contenido y de esta forma se contribuyó a la teoría pedagógica del Desarrollo Sostenible, como complemento de las prioridades de las Cumbres de la Tierra, los llamamientos realizados por la Asamblea General de las Naciones Unidas y la UNESCO para implementar el Decenio de la Educación para el Desarrollo Sostenible en los sistemas educativos. También, se favoreció el aprendizaje de los contenidos con potencialidades para esta educación en el área de Ciencias Exacta del nivel medio superior.

  14. Los rostros de la Educación Física : Un anclaje en sus rasgos en el tercer ciclo de la EGB y el nivel Polimodal

    OpenAIRE

    Leticia Olaso

    2005-01-01

    Al igual que en una tesis, el investigador debe echar luz sobre sus propias concepciones para desde ahí construir su objeto de estudio que no le es ajeno ni distante; más bien forma parte de él. Y sus resultados deben “sorprender” al lector. Esta tesis retoma esta situación del fotógrafo, análoga a la de un investigador de las prácticas de la Educación Física; y pretende describir los rasgos de la Educación Física en las prácticas educativas de los profesores en un colegio confesional de la c...

  15. La radioactividad ambiental

    Directory of Open Access Journals (Sweden)

    Rafael Núñez-Lagos Roglá

    2011-01-01

    Full Text Available Se explican los conceptos fundamentales relacionados con la radiactividad y se utilizan para describir la radiactividad ambiental. Se explican también los isótopos de largo periodo y las principales familias radioactivas junto con la radiación cósmica y los radionucleidos cosmogénicos.

  16. Ambient mass spectrometry imaging

    DEFF Research Database (Denmark)

    Janfelt, Christian; Nørgaard, Asger W

    2012-01-01

    Easy ambient sonic spray ionization (EASI) and desorption electrospray ionization (DESI) were used for imaging of a number of samples, including sections of rat brain and imprints of plant material on porous Teflon. A novel approach termed Displaced Dual-mode Imaging was utilized for the direct c...

  17. Mantenimiento o sustitución de rasgos lingüísticos indexados socialmente: migrantes de zonas andinas en Lima

    Directory of Open Access Journals (Sweden)

    Carola Mick

    2013-12-01

    Full Text Available ResumenEste artículo investiga la relación entre la formación de “mundos de vida comunicativos individuales” y la construcción de la identidad en migrantes peruanas procedentes de la zona de los Andes en Lima. A partir del análisis lingüístico y discursivo de un corpus de entrevistas semidirigidas con veintidós mujeres migrantes mostramos cómo las ideologías lingüísticas, las que menosprecian rasgos dialectales considerados como típicos de migrantes andinos y las que prestigian los “rasgos limeños”, condicionan el comportamiento lingüístico de las migrantes y se transforman en herramientas útiles para el posicionamiento discursivo individual de las informantes frente a estos estereotipos.AbstractThis article enquires the relationship between the formation of “individual communicative lifeworlds” and the construction of identity in 22 semidirective interviews with Peruvian migrant domestic workers in Lima originating from the Andean regions. With the help of a combined linguistic and discursive analysis we demonstrate the way in which language ideologies condition and enable the formation of individual communicative lifeworlds of the speakers. The stigmatization of linguistic characteristics that are considered as typical of “Andean” speakers and the high esteem of linguistic forms considered as typical for people originating in Lima favour linguistic accommodation, but in order to explain all the variation in the corpus we need to take into consideration the individual linguistic and discursive positioning of each speaker.

  18. Sucesiones primarias en páramo: patrones de diversidad, rasgos de historia de vida y su relación con nutrientes (Parque Nacional Natural Chingaza

    Directory of Open Access Journals (Sweden)

    Cobos Acosta Raquel

    2002-06-01

    Full Text Available Se realizó un estudio de sucesiones primarias sobre roca en el páramo de Chingaza (Alto delIndio teniendo en cuenta los patrones de diversidad, rasgos de historias de vida y nutrientes.Se trabajaron dos rocas, cada una dividida en cuatro sectores. El sector uno está en la partesuperior de la roca, donde la pendiente es de 75% y la roca está más expuesta, en los siguientes7070Resúmenes sectores la pendiente y la roca desnuda disminuyen hasta llegar al sector cuatro, donde la pen-diente es de 25% y la cobertura del la roca es de 100%. Se evaluó la composición y abundanciade las especies, con los métodos de punto centrado, línea intercepto y cuadrantes. El métodode cuadrantes registró un mayor número de especies (riqueza en todos los sectores. Se encon-tró que las áreas más diversas están hacia la mitad de la roca, (sector 3 - roca 1 o sector 2 -roca 2, mientras que los sectores menos diversos están hacia los extremos superiores (sector1 -roca 1 o inferiores (sector 4 -roca 2 de los sitios de trabajo. El análisis de correspondenciamostró que las especies relacionadas con los sectores 1 y 2 son principalmente criptógamas.Las especies relacionadas en el sector tres son tanto criptógamas como fanerógamas, y en elsector cuatro se agrupan principalmente las especies fanerógamas. Se plantea un modelo con-ceptual del proceso sucesional primario teniendo en cuenta los rasgos de historias de vida y losfactores que dirigen la sucesión en sus diferentes estados.

  19. Nitrogen Source and Loading Data for EPA Estuary Data Mapper

    Science.gov (United States)

    Nitrogen source and loading data have been compiled and aggregated at the scale of estuaries and associated watersheds of the conterminous United States, using the spatial framework in EPA's Estuary Data Mapper (EDM) to provide system boundaries. Original sources of data include...

  20. A note on salt intrusion in funnel-shaped estuaries: Application to the Incomati estuary, Mozambique

    Science.gov (United States)

    Brockway, Rachel; Bowers, David; Hoguane, Antonio; Dove, Veronica; Vassele, Valentina

    2006-01-01

    Salt intrusion in estuaries is important for ecological reasons as well as water extraction purposes. The distance salt intrudes upstream depends on a number of factors, including river discharge, tidal and wind mixing and gravitational circulation. In this paper, an analytical solution is presented for the salt intrusion in a well mixed, funnel-shaped estuary whose cross sectional area decreases exponentially (with decay coefficient β) with distance, x, inland, and in which longitudinal mixing is constant along the length of the estuary. The solution predicts that a graph of the logarithm of salinity against exp ( βx) should be a straight line, with slope proportional to the mixing coefficient K x. The solution is tested against observations from 15 surveys over a four-year period in the Incomati estuary. Good straight line fits, as predicted, are observed on all surveys, with a mean R2 = 0.97. The average value of K x for all surveys is 38 m 2 s -1. The solution is used to make predictions about the minimum river flow required to prevent salt intruding to an extent where it causes a detrimental effect on water extraction. The minimum recommended river flow required to prevent this is 35 m 3 s -1. In recent years, flow has fallen below this level for several months each year.

  1. Conditions for tidal bore formation in convergent alluvial estuaries

    Science.gov (United States)

    Bonneton, Philippe; Filippini, Andrea Gilberto; Arpaia, Luca; Bonneton, Natalie; Ricchiuto, Mario

    2016-04-01

    Over the last decade there has been an increasing interest in tidal bore dynamics. However most studies have been focused on small-scale bore processes. The present paper describes the first quantitative study, at the estuary scale, of the conditions for tidal bore formation in convergent alluvial estuaries. When freshwater discharge and large-scale spatial variations of the estuary water depth can be neglected, tide propagation in such estuaries is controlled by three main dimensionless parameters: the nonlinearity parameter ε0 , the convergence ratio δ0 and the friction parameter ϕ0. In this paper we explore this dimensionless parameter space, in terms of tidal bore occurrence, from a database of 21 estuaries (8 tidal-bore estuaries and 13 non tidal-bore estuaries). The field data point out that tidal bores occur for convergence ratios close to the critical convergence δc. A new proposed definition of the friction parameter highlights a clear separation on the parameter plane (ϕ0,ε0) between tidal-bore estuaries and non tidal-bore estuaries. More specifically, we have established that tidal bores occur in convergent estuaries when the nonlinearity parameter is greater than a critical value, εc , which is an increasing function of the friction parameter ϕ0. This result has been confirmed by numerical simulations of the two-dimensional Saint Venant equations. The real-estuary observations and the numerical simulations also show that, contrary to what is generally assumed, tide amplification is not a necessary condition for tidal bore formation. The effect of freshwater discharge on tidal bore occurrence has been analyzed from the database acquired during three long-term campaigns carried out on the Gironde/Garonne estuary. We have shown that in the upper estuary the tidal bore intensity is mainly governed by the local dimensionless tide amplitude ε. The bore intensity is an increasing function of ε and this relationship does not depend on freshwater

  2. Greenhouse gas (N2O emission from Portuguese estuaries

    Directory of Open Access Journals (Sweden)

    Célia Gonçalves

    2014-07-01

    Tagus, Minho and Lima estuaries are source of N2O to the atmosphere. Particularly, in Lima estuary anthropogenic N input seems to play an important role on N2O emission. However, in a global perspective N2O attained emissions represent a reduced fraction (2O yr-1, Barnes and Upstill-Goddard, 2011. Values are comparable with those registered in some Portuguese estuaries and other European less eutrophic estuaries. However, it is known that higher N2O emissions in estuaries may occur during winter and spring (Sun et al., 2014. Thus, these systems may represent on an annual basis a larger source of N2O, which can only be clarified in future studies. Only a full comprehension of the global estuarine nitrogen cycle will provide an efficient basis of scientific knowledge for sustainably management of such ecosystems and ultimately reduce N2O emissions.

  3. Ambient Air Quality Data Inventory

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Office of Air and Radiation??s (OAR) Ambient Air Quality Data (Current) contains ambient air pollution data collected by EPA, other federal agencies, as well as...

  4. Ambient Air Quality Data Inventory

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Office of Air and Radiation's (OAR) Ambient Air Quality Data (Current) contains ambient air pollution data collected by EPA, other federal agencies, as well as...

  5. NIF Ambient Vibration Measurements

    International Nuclear Information System (INIS)

    LLNL has an ongoing research and development project that includes developing data acquisition systems with remote wireless communication for monitoring the vibrations of large civil engineering structures. In order to establish the capability of performing remote sensing over an extended period of time, the researchers needed to apply this technology to a real structure. The construction of the National Ignition Facility provided an opportunity to test the data acquisition system on a large structure to monitor whether the facility is remaining within the strict ambient vibration guidelines. This document will briefly discuss the NIF ambient vibration requirements and summarize the vibration measurements performed during the Spring and Summer of 1999. In addition, a brief description of the sensors and the data acquisition systems will be provided in Appendix B

  6. Algae and water pollution in Mahi Estuary

    OpenAIRE

    Jiyalal Ram, M.

    1991-01-01

    Distribution of phytoplankton, chlorophyll A and phaeophytin was studied at different locations in the Mahi Estuary, Gujarat, India during 1982. The water quality at the discharge point was poor while the region away from it was relatively unpolluted. The results indicated a wide range of variation in phytoplankton population (7.68-5010, 96 x 10 super(4) cells/l, chl. a 2.22-58.22 mg/m super(3) and phaeophytin [0.20-10.21 mg/m super(3)]. The ratio of chl. a/phaeophytin were remarkably low at ...

  7. Salud ambiental: conceptos y actividades

    OpenAIRE

    Ordóñez Gonzalo A.

    2000-01-01

    La finalidad del trabajo es aportar información y propuestas conceptuales que faciliten la tarea de quienes tienen a su cargo la sistematización institucional de la salud ambiental. Se hace un análisis de la noción de "ambiente" para la cual se sugiere una definición, y se examina el lugar de la salud ambiental en el contexto de los problemas ambientales y sus vertientes "verde" y "azul". Se examinan denominaciones equivalentes de salud ambiental y se introducen los servicios de salud ambient...

  8. Mercury distribution in Douro estuary (Portugal)

    International Nuclear Information System (INIS)

    Determinations of dissolved reactive and total dissolved mercury, particulate and sedimentary mercury, dissolved organic carbon (DOC), particulate organic carbon (POC) and suspended particulate matter (SPM) have been made in the estuary of river Douro, in northern Portugal. The estuary was stratified by salinity along most of its length, it had low concentrations of SPM, typically -3, and concentrations of DOC in the range -3. The surface waters had a maximum dissolved concentration of reactive mercury of about 10 ng dm-3, whereas for the more saline bottom waters it was about 65 ng dm-3. The surface waters had maximum concentrations of total suspended particulate mercury of ∼7 μg g-1 and the bottom waters were always -1. Concentrations of mercury in sediments was low and in the range from 0.06 to 0.18 μg g-1. The transport of mercury in surface waters was mainly associated with organic-rich particulate matter, while in bottom waters the dissolved phase transport of mercury is more important. Lower particulate organic matter, formation of chlorocomplexes in more saline waters and eventually the presence of colloids appear to explain the difference of mercury partitioning in Douro estuarine waters

  9. Study of Bed Friction Factor for the Wu River Estuary

    Institute of Scientific and Technical Information of China (English)

    Chin-Wu LAN; Cyuan-Chen LEE

    2006-01-01

    In this research the bed friction effect is estimated of a river estuary by use of hydrodynamic analysis. The on-site sampled data of the Wu River estuary is applied to the analysis. There are many dynamic factors that affect the flow characteristics in the estuary. The effect of tide on the generation of tidal current, bottom friction and geometry effect is the focus of this paper. The Wu River estuary is about 15 km in length, with a small bottom slope and no physical obstruction; thus the incident wave at the estuary is considered a progressive wave with damping effect. The amplitude reduction and phase shift of the incident wave are analyzed. By the analysis of celerity reduction factor of the estuary, the estimated value of mean resistance coefficient M(μ,κ), damping modulus μ, and wave number κ for the sections at observation stations can be determined. Furthermore, data gathered from on-site observations are applied for validation. Finally, Manning's coefficient for each section of the observation stations can be determined. It is found that the value of Manning's coefficient is small downstream and increases towards upstream, and that the bed friction effect of an estuary varies largely. The estimated results of the paper are compared with the empirical formulas and the modified solution for practical application is discussed.

  10. Temporal Variability of Nutrient Budgets in a Tropical River Estuary

    Directory of Open Access Journals (Sweden)

    Thanomsak Boonphakdee

    2008-01-01

    Full Text Available Water, salt, dissolved inorganic nitrogen (DIN, and dissolved inorganic phosphorus (DIP budgets in the Bangpakong Estuary were conducted by repeated observations and multiple box modeling. Water samples for inorganic nutrient analyses were collected monthly from June 2000 to May 2001. Flushing time at the estuary depicts high variations ranging from 1.4 (October 2000 to 80 days (February 2001 with an annual mean of 15.2 days. Seasonal variation in salinity gradients and estuarine Richardson numbers show the Bangpakong Estuary was partially stratified during the wet season and a well-mixed estuary in the dry season. Riverine nutrient inputs and distributions of nutrient concentrations within the river estuary varied in space and time. Temporal variations in fluxes were strong within inter-seasonal scales owing to water fluxes and system concentrations. The increase of DIN and DIP fluxes in the estuary may be the results of degradation of particulate organic matter. The Bangpakong Estuary appears to be a heterotrophic system where respiration exceeds photosynthesis (p-r < 0 and a denitrifying system. Seasonal variations in biogeochemical rates were attributable to differences in magnitude of freshwater inputs.

  11. River flow and ammonium discharge determine spring phytoplankton blooms in an urbanized estuary

    Science.gov (United States)

    Dugdale, Richard; Wilkerson, Frances; Parker, Alexander E.; Marchi, Al; Taberski, Karen

    2012-12-01

    Nutrient loadings to urbanized estuaries have increased over the past decades in response to population growth and upgrading to secondary sewage treatment. Evidence from the San Francisco Estuary (SFE) indicates that increased ammonium (NH4) loads have resulted in reduced primary production, a counter-intuitive finding; the NH4 paradox. Phytoplankton uptake of nitrate (NO3), the largest pool of dissolved inorganic nitrogen, is necessary for blooms to occur in SFE. The relatively small pool of ambient NH4, by itself insufficient to support a bloom, prevents access to NO3 and bloom development. This has contributed to the current rarity of spring phytoplankton blooms in the northern SFE (Suisun Bay), in spite of high inorganic nutrient concentrations, improved water transparency and seasonally low biomass of bivalve grazers. The lack of blooms has likely contributed to deleterious bottom-up impacts on estuarine fish. This bloom suppression may also occur in other estuaries that receive large amounts of anthropogenic NH4. In 2010 two rare diatom blooms were observed in spring in Suisun Bay (followed by increased abundances of copepods and pelagic fish), and like the prior bloom observed in 2000, chlorophyll accumulated after NH4 concentrations were decreased. In 2010, low NH4 concentrations were apparently due to a combination of reduced NH4 discharge from a wastewater treatment plant and increased river flow. To understand the interactions of river flow, NH4 discharge and bloom initiation, a conceptual model was constructed with three criteria; 1) NH4 loading must not exceed the capacity of the phytoplankton to assimilate the inflow of NH4, 2) the NH4 concentration must be ≤4 μmol L-1 to enable phytoplankton NO3 uptake, 3) the dilution rate of phytoplankton biomass set by river flow must not exceed the phytoplankton growth rate to avoid "washout". These criteria were determined for Suisun Bay; with sufficient irradiance and present day discharge of 15 tons NH4-N d

  12. Arquitectura y medio ambiente

    OpenAIRE

    Saura Carulla, Magdalena

    2003-01-01

    La arquitectura y la planificación son el resultado de una integración ponderada de conocimientos técnicos y una multiplicidad de aspectos relacionados con el conocimiento natural y social. En este trabajo el autor propone, desde el ámbito de las ciencias del medio ambiente, diversos planteamientos teóricos y prácticos relacionados con la arquitectura y el urbanismo. El conocimiento de la naturaleza de los sistemas naturales y de los sistemas ecosociales permite al diseñador aplicar un marco ...

  13. Ambiente il nostro futuro

    OpenAIRE

    Canigiani, Franca

    2016-01-01

    L’ambiente è il quadro di vita, la casa comune, il patrimonio di base delle società umane – scriveva un indimenticabile maestro della geografia italiana: Giuseppe Barbieri. Due gli avvenimenti che nel 2015 hanno segnato il passo dell’umanità sulla strada di una più matura coscienza ambientale, fino a comprendere che è necessario e urgente prendersi cura della Terra: primo, la pubblicazione della lettera enciclica di papa Francesco, Laudato si’ sulla cura della casa comune, straordinario saggi...

  14. AOX y medio ambiente.

    OpenAIRE

    Riva Juan, Mª del Carmen; López Ribas, David

    1996-01-01

    Los productos organohalogenados son muy utilizados por la industria y su presencia en el medio ambiente está siendo controlada. En los últimos años se han desarrollado varias técnicas de detección, siendo desde finales de los 80 los AOX (adsorbable organic halogens) uno de los parámetros sobre los que se han realizado más estudios. En muchos paises de la Unión Europea y en E.E.U.U. de América, la presencia de compuestos organohalogenados en aguas continentales y suelos está legislada indicand...

  15. Mass and salt transfers and halocline depths in an estuary

    OpenAIRE

    LONG, ROBERT R.

    2011-01-01

    The paper considers fluxes of brackish and ocean water out of and into an estuary as well as the depth of the halocline in the estuary. The discussion ignores the details of the mass distribution and circulations in the main body of the estuary (except for the halocline depth) and concentrates on determining the flow conditions and interface depths in the vicinity of the mouth. The flow there is considered to be frictionless and the pressure hydrostatic, and the first part of the analysis, wh...

  16. Oysters return to the Tagus estuary through an ecological model

    OpenAIRE

    Bento, Vânia Sofia de Oliveira

    2008-01-01

    Aquaculture is an activity that has been increasing along the last years. Until the 1970’s Portugal and more specifically the Tagus estuary, was the major exporter of oysters in Europe. Factors like TBT and oysters gill disease had made that the shellfish aquaculture has never been again practised in Tagus estuary. According to that, this work intends to concept and to implement an ecological model that develops the oysters growth in order to them return to the estuary. To begin with, the ...

  17. Waterfowl migration and distribution in North West estuaries. V. 1

    International Nuclear Information System (INIS)

    Waterfowl populations may be affected by proposed tidal barrage across the Mersey. This study had three objectives:-(1) to evaluate the patterns of usage of the intertidal flats of the Mersey estuary by waders and wildfowl and to establish which are the preferred areas; (2) to identify the places of origin and movement patterns of the populations of waders and wildfowl that visit the Mersey Estuary; and (3) to evaluate evidence regarding the capacity of British estuaries to absorb waders and wildfowl populations which might be displaced by a Mersey Barrage. The text and tables and results only are presented in Volume 1. (author)

  18. Crisis ambiental y cristianismo

    Directory of Open Access Journals (Sweden)

    Felipe Cárdenas

    2008-01-01

    Full Text Available En el artículo se identifican y reconocen algunas opciones que se pueden desarrollar en el cristianismo en relación con la problemática ambiental. Se aborda el dilema bíblico suscitado por interpretaciones antiecológicas y ecológicas. Con base en una lectura de la Biblia, de testimonios cristianos, y en una rememoria de estructuras institucionales, como la parroquia, se analiza el valor que tiene el mensaje cristiano en lo referido a la mitigación de la crisis ambiental.This article identifies and recognizes some options that can be developed in Christianity in relation to the environmental problem. It starts by analyzing the biblical dilemma provoked by both ecological and antiecological interpretations. Based on a reading of the Bible, testimonies from Christians and with a rememory of institutional structures, like the parish, the valué of the Christian message for mitigating the environmental crisis is analyzed.

  19. Rasgos estructurales en la Sierra Pampeana de Velasco y alrededores a partir de los campos gravimétricos y magnetrométricos

    Directory of Open Access Journals (Sweden)

    Marcos A Sánchez

    2013-06-01

    Full Text Available La región que comprende la sierra de Velasco y el Sistema de Famatina, en el centro-oeste de la Provincia de La Rioja - Argentina, es un área clave para el estudio de la amalgamación de terrenos y tectónica vinculada con el levantamiento andino. En éste trabajo, se definen algunos rasgos de la estructura cortical de ésta región. Para ello, mediante la aplicación de métodos potenciales (gravedad y magnetismo, adecuadamente procesados e interpretados a través de técnicas semiautomáticas y de resalto de anomalías, se logró determinar: a una región que respondería a la zona de sutura entre los terrenos Famatina y Pampia y b fallas relacionadas al levantamiento de las sierras de Famatina y de Velasco. Los resultados anteriores se representan en una sección este - oeste en un modelo estructural de bloques de basamento entre Famatina y Velasco, hasta 12 km de profundidad. En él señalamos además la distribución de las fallas y sus buzamientos.

  20. Relación entre variabilidad biogeoquímica y rasgos estructurales de la comunidad microbiana en suelos forestales: Bosques de Abies pinsapo como caso de estudio

    Directory of Open Access Journals (Sweden)

    P. Torres-Cañabate

    2009-01-01

    Full Text Available Relación entre variabilidad biogeoquímica y rasgos estructurales de la comunidad microbiana en suelos forestales: Bosques de Abies pinsapo como caso de estudio. Tradicionalmente, los estudios biogeoquímicos consideraban el suelo como una "caja negra", conectada con el resto del ecosistema mediante flujos de entrada y de salida de nutrientes, en la que éstos experimentan transformaciones mediadas engran parte por microorganismos desconocidos. El desarrollo de nuevas técnicas moleculares ha incrementado el conocimiento sobre lascomunidades microbianas del suelo. Estudios recientes han puesto de manifiesto correspondencias entre la variabilidad de la disponibilidad de nutrientes y la estructura de la comunidad microbiana en suelos forestales. A este respecto, hemos empleado bosques de Abies pinsapo como modelo ya que muestran una gran variabilidad biogeoquímica asociada a diferencias litológicas y sucesionales, mientras que la estacionalidad mediterránea provoca una alta variabilidad intra-anual en la disponibilidad de nutrientes. Además, existen pinsapares sujetos alimitación o a saturación de nitrógeno. Mediante análisis del polimorfismo de longitud de fragmentos de restricción terminal (T-RFLP, hemos puesto de manifiesto que los patrones de variabilidad biogeoquímica descritos en los pinsapares se corresponden con cambios en la composición y estructura de sus comunidades bacterianas.

  1. Discriminación experimental de los rasgos técnicos en la talla bipolar y a mano alzada en lascas a través los cuarzos de Naibor Soit (Garganta de Olduvai, Tanzania

    Directory of Open Access Journals (Sweden)

    Domínguez Rodrigo, M.

    2012-01-01

    Full Text Available La identificación de la talla bipolar puede ser controvertida debido fundamentalmente a la naturaleza petrográfica del cuarzo y a su fracturación heterogénea. Este trabajo pretende superar este problema mediante el desarrollo de un marco explicativo experimental destinado al reconocimiento de los rasgos diagnósticos en las lascas producidas por ambos métodos de talla en la reducción del cuarzo de Naibor Soit (Garganta de Olduvai, Tanzania. El objetivo final de este trabajo es el de utilizar un conjunto de variables relacionadas con la respuesta de esta materia prima a la fractura a mano alzada y bipolar en dos experimentos destinados a individualizar estadísticamente los rasgos técnicos diagnósticos que mejor identifican a la talla bipolar en este tipo de materia prima.

  2. Types for BioAmbients

    CERN Document Server

    Capecchi, Sara; 10.4204/EPTCS.19.7

    2010-01-01

    The BioAmbients calculus is a process algebra suitable for representing compartmentalization, molecular localization and movements between compartments. In this paper we enrich this calculus with a static type system classifying each ambient with group types specifying the kind of compartments in which the ambient can stay. The type system ensures that, in a well-typed process, ambients cannot be nested in a way that violates the type hierarchy. Exploiting the information given by the group types, we also extend the operational semantics of BioAmbients with rules signalling errors that may derive from undesired ambients' moves (i.e. merging incompatible tissues). Thus, the signal of errors can help the modeller to detect and locate unwanted situations that may arise in a biological system, and give practical hints on how to avoid the undesired behaviour.

  3. Types for BioAmbients

    Directory of Open Access Journals (Sweden)

    Sara Capecchi

    2010-02-01

    Full Text Available The BioAmbients calculus is a process algebra suitable for representing compartmentalization, molecular localization and movements between compartments. In this paper we enrich this calculus with a static type system classifying each ambient with group types specifying the kind of compartments in which the ambient can stay. The type system ensures that, in a well-typed process, ambients cannot be nested in a way that violates the type hierarchy. Exploiting the information given by the group types, we also extend the operational semantics of BioAmbients with rules signalling errors that may derive from undesired ambients' moves (i.e. merging incompatible tissues. Thus, the signal of errors can help the modeller to detect and locate unwanted situations that may arise in a biological system, and give practical hints on how to avoid the undesired behaviour.

  4. Fluxes of nitrogen in Chaliyar River Estuary, India

    Digital Repository Service at National Institute of Oceanography (India)

    Xavier, J.K.; Joseph, T.; Paimpillii, J.S.

    contribution of external nutrient supply, nutrient budget, geo-chemical and biochemical pathways . The major source of nitrogen in the estuary is the river discharge. During pre-monsoon period, the percentage of inorganic nitrogen to total nitrogen pool...

  5. Toxicity of sediments and pore water from Brunswick Estuary, GA

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A chlor-alkali plant in Brunswick, Ga, discharged >2 kg mercury/day into a tributary of the Turtle River-Brunswick Estuary from 1966 to 1971. Mercury...

  6. The application of Yangtze Estuary Tidal Wetlands Geographic Information System

    Institute of Scientific and Technical Information of China (English)

    WANGJun; CHENZhenlou; XUShiyuan; WANGDongqi; LIUJie

    2005-01-01

    Yangtze Estuary Tidal Wetlands Geographic Information System (YETWGIS) is a comprehensive software system for environmental management and decision of Yangtze estuary tidal wetlands. Based on MapObjects components technology, Data Mining technology, mathematical modeling method and Visual Basic language, this software system has many functions such as displaying, editing, querying and searching, spatial statistics and analysis, thematic map compiling, and environmental quality evaluation. This paper firstly outlined the system structure, key techniques, and achieving methods of YETWGIS, and then, described the core modules (the thematic map compiling module and environmental quality evaluation model module) in detail. In addition, based on information entropy model, it thoroughly discussed the methods of environmental quality evaluation and indicators' weight calculation. Finally, by using YETWGIS, this paper analyzed the spatial distribution characteristics of Heavy Metal and Persistent Organic Pollutants (POPs) of the Yangtze estuary tidal wetlands in 2002, and evaluated the environmental quality of the Yangtze estuary tidal wetlands in 2003.

  7. The larvae of decapods and fishes of Amba estuary, Maharashtra

    Digital Repository Service at National Institute of Oceanography (India)

    Paulinose, V.T.; Devi, C.B.L.; Govindan, K.; Gajbhiye, S.N.; Nair, V.R.

    Larvae of fishes and decapods found in zooplankton collections from two stations (Mankule and Patalganga) in Amba estuary adjoining Mumbai harbour were studied during 1989-90 covering three seasons. The percentage contributions of decapods and fish...

  8. St. Louis River Estuary 2011 - 2013 Faucet snail location data

    Data.gov (United States)

    U.S. Environmental Protection Agency — The dataset consists of GPS coordinates for benthic invertebrate collections made in the St. Louis River Estuary in 2011 through 2013, and information on whether...

  9. MODIS water quality algorithms for northwest Florida estuaries

    Science.gov (United States)

    Synoptic and frequent monitoring of water quality parameters from satellite is useful for determining the health of aquatic ecosystems and development of effective management strategies. Northwest Florida estuaries are classified as optically-complex, or waters influenced by chlo...

  10. Primary productivity in Mandovi-Zuari estuaries in Goa

    Digital Repository Service at National Institute of Oceanography (India)

    KrishnaKumari, L.; Bhattathiri, P.M.A.; Matondkar, S.G.P.; John

    -1 Primary productivity in Mandovi-Zuari estuaries in Goa L. Krishna Kumari, P. M. A. Bhattathiri, S.G.P. Matondkar and Julie John National Institute of Oceanography, Dona Paula, Goa - 403 004, India Abstract Measurement on primary production...

  11. Seasonal shift in net ecosystem production in a tropical estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Ram, A.S.P.; Nair, S.; Chandramohan, D.

    phosphorous to the ocean and dissolved inorganic carbon to the atmosphere (Smith and Hollibaugh 1993; Sarma et al. 2001). Our studies suggest that the persistence of net auto- trophy during the nonmonsoon in estuaries could have re- sulted in production...

  12. Evaluating Causes of Ecological Impairments in the Estuaries of Ukraine

    Science.gov (United States)

    Ukrainian estuaries have not undergone a systematic evaluation of the causes of ecological impairments caused by anthropogenic contamination. The objective of this evaluation is to use recently developed diagnostic tools to determine the causes of benthic ecological impairments. ...

  13. Habitat Scale Mapping of Fisheries Ecosystem Service Values in Estuaries

    Directory of Open Access Journals (Sweden)

    Steve J. Jordan

    2010-12-01

    Full Text Available Little is known about the variability of ecosystem service values at spatial scales most relevant to local decision makers. Competing definitions of ecosystem services, the paucity of ecological and economic information, and the lack of standardization in methodology are major obstacles to applying the ecosystem-services approach at the estuary scale. We present a standardized method that combines habitat maps and habitat–faunal associations to estimate ecosystem service values for recreational and commercial fisheries in estuaries. Three case studies in estuaries on the U.S. west coast (Yaquina Bay, Oregon, east coast (Lagoon Pond, Massachusetts, and the Gulf of Mexico (Weeks Bay, Alabama are presented to illustrate our method’s rigor and limitations using available data. The resulting spatially explicit maps of fisheries ecosystem service values show within and between estuary variations in the value of estuarine habitat types that can be used to make better informed resource-management decisions.

  14. Heavy metal accumulation in a flow restricted, tropical estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Balachandran, K.K.; Laluraj, C.M.; Nair, M.; Joseph, T.; Sheeba, P.; Venugopal, P.

    the region among the impacted estuaries in the world. Accumulation of metals in this estuarine system is aggravated by the weak flushing. These pressures are deemed inevitable with growth initiated in the harbour and associated with mega city development...

  15. Reduced river discharge intensifies phytoplankton bloom in Godavari estuary, India

    Digital Repository Service at National Institute of Oceanography (India)

    Acharyya, T.; Sarma, V.V.S.S.; Sridevi, B.; Venkataramana, V.; Bharathi, M.D.; Naidu, S.A.; Kumar, B.S.K.; Prasad, V.R.; Bandyopadhyay, D.; Reddy, N.P.C.; DileepKumar, M.

    . Biogeochemical aspects of Indian estuaries have been mostly studied concerning nutrient dynamics (Mukhopadhyay et al., 2006; Sarma et al., 2010), inorganic and organic carbon biogeochemistry and trace gases(Bouillon et al., 2003; Bouillon et al., 2000; Sarma... of nutrients in Godavari estuary by Sarma et al.(2010).They observed that significant amount of nutrients (>80 µM of dissolved inorganic nitrogen (DIN) and >12 µM of dissolved inorganic phosphate (DIP)) were associated with peak discharge. However, during...

  16. Biota and abiotic environment in the Westerschelde estuary

    OpenAIRE

    Heip, C. H. R.

    1988-01-01

    An estuary such as the Westerschelde is a highly dynamic environment, both on an ecological time scale where climatic and hydrodynamic forces, mainly the tides, shape a very variable environment and on a geological, evolutionary time scale, since estuaries are young and very unstable habitats. Low species diversity and high adaptability of the resident animal and plant populations are characteristic of estuarine habitats where large fluctuations in submersion, salinity, temperature etc. occur...

  17. Functional diversity of fish in estuaries at a global extent

    OpenAIRE

    Rita P. Vasconcelos; Sébastien Villéger; François Guilhaumon

    2015-01-01

    Biodiversity is currently viewed as a framework encompassing multiple facets of the variety of life, including taxonomic and functional aspects. Species richness and composition of fish assemblages in estuaries is defined by global to local processes acting on community colonization. The present study further investigates how biodiversity of fish assemblages varies among estuaries globally, by simultaneously analysing taxonomic and functional richness and diversity of assemblages. A comprehen...

  18. Biological effects of anthropogenic contaminants in the San Francisco Estuary

    Science.gov (United States)

    Thompson, B.; Adelsbach, T.; Brown, C.; Hunt, J.; Kuwabara, J.; Neale, J.; Ohlendorf, H.; Schwarzbach, S.; Spies, R.; Taberski, K.

    2007-01-01

    Concentrations of many anthropogenic contaminants in the San Francisco Estuary exist at levels that have been associated with biological effects elsewhere, so there is a potential for them to cause biological effects in the Estuary. The purpose of this paper is to summarize information about biological effects on the Estuary's plankton, benthos, fish, birds, and mammals, gathered since the early 1990s, focusing on key accomplishments. These studies have been conducted at all levels of biological organization (sub-cellular through communities), but have included only a small fraction of the organisms and contaminants of concern in the region. The studies summarized provide a body of evidence that some contaminants are causing biological impacts in some biological resources in the Estuary. However, no general patterns of effects were apparent in space and time, and no single contaminant was consistently related to effects among the biota considered. These conclusions reflect the difficulty in demonstrating biological effects due specifically to contamination because there is a wide range of sensitivity to contaminants among the Estuary's many organisms. Additionally, the spatial and temporal distribution of contamination in the Estuary is highly variable, and levels of contamination covary with other environmental factors, such as freshwater inflow or sediment-type. Federal and State regulatory agencies desire to develop biological criteria to protect the Estuary's biological resources. Future studies of biological effects in San Francisco Estuary should focus on the development of meaningful indicators of biological effects, and on key organism and contaminants of concern in long-term, multifaceted studies that include laboratory and field experiments to determine cause and effect to adequately inform management and regulatory decisions. ?? 2006 Elsevier Inc. All rights reserved.

  19. Salt intrusion study in Cochin estuary - Using empirical models

    Digital Repository Service at National Institute of Oceanography (India)

    Jacob, B.; Revichandran, C.; NaveenKumar, K.R.

    IN COCHIN ESTUARY 309 as well as the calculated results of Van der Burge models show great correlation between river discharge and salinity intrusion length (Table 1). Two counteracting effects determine the effect of tidal amplitude. Large tidal... since salinity incursion was not strong enough to completely mask the effect of fresh water flow. During the pre-monsoon, the river discharge is minimum and seawater influence is maximum upstream, the estuary is well-mixed and homogeneity exists...

  20. Contamination and restoration of an estuary affected by phosphogypsum releases

    International Nuclear Information System (INIS)

    The Huelva Estuary in Huelva, Spain, has been one of the most studied environmental compartments in the past years from the point of view of naturally occurring radioactive material (NORM) releases. It has been historically affected by waste releases, enriched in radionuclides from the U-decay series, from factories located in the area devoted to the production of phosphoric acid and phosphate fertilizers. Nevertheless, changes in national regulations forced a new waste management practice in 1998, prohibiting releases of phosphogypsum into the rivers. The input of natural radionuclides from phosphate factories to rivers was drastically reduced. Because of this there was a unique opportunity for the study of the response of a contaminated environmental compartment, specifically an estuary affected by tidal influences, after the cessation of the contaminant releases to, in this case, the Huelva Estuary (henceforth referred to as the Estuary). To investigate the environmental response to this new discharge regime, the specific activities of radionuclides 226Ra and 210Pb in water and sediment samples collected in four campaigns (from 1999 to 2005) were determined and compared with pre-1998 values. From this study it is possible to infer the most effective mechanisms of decontamination for the Estuary. Decontamination rates of 210Pb and 226Ra in the sediments and water have been calculated using exponential fittings and corresponding half-lives have been deduced from them. The cleaning half-life in the whole area of the Estuary is about 6 and 3.5 years for 226Ra and 210Pb respectively. The observed trend clearly shows that contamination of the Estuary by natural radionuclides is now decreasing and radioactive levels in waters and sediments are approaching the natural background references. This work attempts to evaluate whether it can be expected that the decontamination of the enhanced levels of natural radioactivity in the Estuary can be performed via natural

  1. Contamination and restoration of an estuary affected by phosphogypsum releases

    Energy Technology Data Exchange (ETDEWEB)

    Villa, M., E-mail: mvilla@us.es [Centro de Investigacion, Tecnologia e Innovacion, Universidad de Sevilla CITIUS, Av. Reina Mercedes 4B, E41012-Sevilla (Spain); Mosqueda, F. [Dpto. de Fisica Aplicada, Facultad de Ciencias Experimentales, Universidad de Huelva, Campus de El Carmen, 21007-Huelva (Spain); Hurtado, S. [Centro de Investigacion, Tecnologia e Innovacion, Universidad de Sevilla CITIUS, Av. Reina Mercedes 4B, E41012-Sevilla (Spain); Mantero, J.; Manjon, G. [E. T. S. Arquitectura, Universidad de Sevilla, Departamento de Fisica Aplicada II, Av. Reina Mercedes, 2. 41012-Sevilla (Spain); Perianez, R. [E.U.I.T.A., Universidad de Sevilla, Departamento de Fisica Aplicada III, Carretera de Utrera, Km. 1, 41013 Sevilla (Spain); Vaca, F. [Dpto. de Fisica Aplicada, Facultad de Ciencias Experimentales, Universidad de Huelva, Campus de El Carmen, 21007-Huelva (Spain); Garcia-Tenorio, R. [E. T. S. Arquitectura, Universidad de Sevilla, Departamento de Fisica Aplicada II, Av. Reina Mercedes, 2. 41012-Sevilla (Spain)

    2009-12-15

    The Huelva Estuary in Huelva, Spain, has been one of the most studied environmental compartments in the past years from the point of view of naturally occurring radioactive material (NORM) releases. It has been historically affected by waste releases, enriched in radionuclides from the U-decay series, from factories located in the area devoted to the production of phosphoric acid and phosphate fertilizers. Nevertheless, changes in national regulations forced a new waste management practice in 1998, prohibiting releases of phosphogypsum into the rivers. The input of natural radionuclides from phosphate factories to rivers was drastically reduced. Because of this there was a unique opportunity for the study of the response of a contaminated environmental compartment, specifically an estuary affected by tidal influences, after the cessation of the contaminant releases to, in this case, the Huelva Estuary (henceforth referred to as the Estuary). To investigate the environmental response to this new discharge regime, the specific activities of radionuclides {sup 226}Ra and {sup 210}Pb in water and sediment samples collected in four campaigns (from 1999 to 2005) were determined and compared with pre-1998 values. From this study it is possible to infer the most effective mechanisms of decontamination for the Estuary. Decontamination rates of {sup 210}Pb and {sup 226}Ra in the sediments and water have been calculated using exponential fittings and corresponding half-lives have been deduced from them. The cleaning half-life in the whole area of the Estuary is about 6 and 3.5 years for {sup 226}Ra and {sup 210}Pb respectively. The observed trend clearly shows that contamination of the Estuary by natural radionuclides is now decreasing and radioactive levels in waters and sediments are approaching the natural background references. This work attempts to evaluate whether it can be expected that the decontamination of the enhanced levels of natural radioactivity in the Estuary

  2. Reforma constitucional y ambiente

    Directory of Open Access Journals (Sweden)

    Teodoro Bustamante

    2013-09-01

    Full Text Available América Latina está atravesada por una ola de reformas constitucionales. Sus causas, las expectativas que ellas despiertan, los riesgos que se han asociado al proceso de lucha política en su entorno, son temas de un análisis fundamentalmente político; pero hay algunos aspectos en los cuales ese debate tiene una directa repercusión sobre el tema ambiental. En el caso del Ecuador, esto se refleja en el hecho de que una de las innovaciones que se proponen, se refieren a una nueva forma de abordar los temas ambientales, básicamente se establecen Derechos de la Naturaleza.

  3. MEIO AMBIENTE E DESENVOLVIMENTO

    OpenAIRE

    Suely Salgueiro Chacon; Daniel Rodriguez de Carvalho Pinheiro; Francisco Correia de Oliveira; Elizabeth Castelo Branco de Souza

    2009-01-01

    O objetivo deste artigo é resgatar elementos para subsidiar uma reflexão crítica sobre o modelo de desenvolvimento econômico prevalente na sociedade e as relações com o meio ambiente, sob a ameaça que ronda o destino da espécie humana, conforme afirmação de Lovelock (2006, p. 20) sobre o conceito de desenvolvimento sustentável: “uma ideia adorável se a tivéssemos aplicado 200 anos atrás, quando havia um bilhão de pessoas no mundo. Agora é tarde demais. Não há mais espaço para nenhum tipo de d...

  4. Estrategia Ambiental Provincial

    Directory of Open Access Journals (Sweden)

    Angel A. Alfonso

    2010-10-01

    Full Text Available El trabajo que se presenta constituye la Estrategia Ambiental Provincial, elaborada por un Colectivo de Autores  formado por especialistas e investigadores de la Delegación Provincial del CITMA en Matanzas. Esta Estrategia ha sido onfeccionada según el marco de las orientaciones contenidas en la Estrategia Nacional y aborda los principales problemas medio ambientales presentados de forma jerárquica así como los instrumentos para la materialización de dicha Estrategia. El Resultado, primero de su tipo en el país, se elaboró con la aplicación de técnicas y métodos de la investigación científica, tales como: Método de Expertos, tormentas de ideas, método de los grupos nominales, método Delphi, método de votación directa o ponderada, Saaty etc. Los antecedentes principales que permitieron la obtención del Resultado fueron el Diagnóstico de la Situación Ambiental de la Provincia, las Estrategias Ambientales de las principales Empresas o Sectores de la Economía del territorio y los Diagnósticos de las Cuencas Hidrográficas. Se contó además con la colaboración de especialistas de otras instituciones provinciales tales como el Centro Provincial de Higiene y Epidemiología, Instituto de Recursos Hidráulicos, Empresa Nacional de Proyectos Agropecuarios del MINAGRI. El resultado fue constituído como política en el territorio en el mes de abril de 1998 con su aprobación por el Consejo de la Administración Provincial. 

  5. Conservation of Thane Creek and Ulhas River Estuary, India.

    Science.gov (United States)

    Nikam, Vinay S; Kumar, Arun; Lalla, Kamal; Gupta, Kapil

    2009-07-01

    There has been a steady decrease in the area occupied by wetlands in creeks and estuaries adjacent urban areas due to unprecedented urban growth in coastal cities, for example, Thane Creek and Ulhas River Estuary near Mumbai, India. Urban cities serve as centres of employment and attract a large number of migrants from other places. In case of coastal cities, due to inadequate infrastructure, wastewater and solid waste are disposed of into wetlands and estuary. Discharge of sediments and solid waste into the creeks from drains and construction activities has resulted in decreased flow depth in the coastal waters of Thane Creek and Ulhas River Estuary. Various researchers have studied individual elements of Thane Creek and Ulhas River Estuary at micro level. However, a holistic approach for restoration and conservation of the creek and estuary is required. This paper presents the details of an integrated approach incorporating different conservation measures such as sewerage and sewage treatment, urban drainage management, solid waste management, mangrove plantation and dredging. PMID:21117428

  6. Sources, Ages, and Alteration of Organic Matter in Estuaries

    Science.gov (United States)

    Canuel, Elizabeth A.; Hardison, Amber K.

    2016-01-01

    Understanding the processes influencing the sources and fate of organic matter (OM) in estuaries is important for quantifying the contributions of carbon from land and rivers to the global carbon budget of the coastal ocean. Estuaries are sites of high OM production and processing, and understanding biogeochemical processes within these regions is key to quantifying organic carbon (Corg) budgets at the land-ocean margin. These regions provide vital ecological services, including nutrient filtration and protection from floods and storm surge, and provide habitat and nursery areas for numerous commercially important species. Human activities have modified estuarine systems over time, resulting in changes in the production, respiration, burial, and export of Corg. Corg in estuaries is derived from aquatic, terrigenous, and anthropogenic sources, with each source exhibiting a spectrum of ages and lability. The complex source and age characteristics of Corg in estuaries complicate our ability to trace OM along the river-estuary-coastal ocean continuum. This review focuses on the application of organic biomarkers and compound-specific isotope analyses to estuarine environments and on how these tools have enhanced our ability to discern natural sources of OM, trace their incorporation into food webs, and enhance understanding of the fate of Corg within estuaries and their adjacent waters.

  7. Validating Firewalls in Mobile Ambients

    DEFF Research Database (Denmark)

    Nielson, Flemming; Nielson, Hanne Riis; Hansen, René Rydhof; Jensen, J. G.

    The ambient calculus is a calculus of computation that allows active processes (mobile ambients) to move between sites. A firewall is said to be protective whenever it denies entry to attackers not possessing the required passwords. We devise a polynomial time algorithm for rejecting proposed...

  8. Foro Ambiental : CEDENMA, Asamblea Constituyente

    Directory of Open Access Journals (Sweden)

    Anne-Lise Naizot

    2013-09-01

    Full Text Available Resumen de la Mesa redonda: Orientaciones de la nueva Constitución ecuatoriana en materia ambiental: ¿avances o retrocesos en relación con el marco político y filosófico ambiental vigente en algunos países de la región?

  9. Aptitud Física y su Relación con Rasgos Depresivos en Personas Adultas Mayores que Realizan Actividad Física

    Directory of Open Access Journals (Sweden)

    Mynor Rodríguez-Hernández

    2014-08-01

    Full Text Available El propósito de esta investigación fue determinar la relación entre la aptitud física y los niveles depresivos en las personas adultas mayores que participan en programas de actividad física en el área de San Ramón, Alajuela. Un total de 138 personas mayores con edades entre los 60 y 86 años (67.94 ± 5.26 años, fueron medidas en los componentes de la aptitud física mediante la prueba “Senior Fitness Test” (SFT y los niveles de depresión mediante la Escala de Depresión Geriátrica de “Yesavage” (GDS, “Geriatric Depression Scale” por sus siglas en Inglés. Los resultados sugieren que el 97,8 % de las personas analizadas se ubicó dentro de los parámetros normales y excelentes de aptitud física, mientras tanto, el 86,2 % se encontró en la etapa normal de la depresión. Por su parte, la depresión geriátrica correlacionó negativamente con la aptitud física en las variables: fuerza muscular y resistencia corporal de la parte baja del cuerpo, resistencia de la fuerza muscular del brazo, la agilidad y equilibrio dinámico, y flexibilidad parte baja del cuerpo (p <0,05. Se concluye que a mayor nivel de aptitud física menor son los rasgos depresivos en personas adultas mayores.

  10. La democracia mexicana, presa de una cultura política con rasgos autoritarios Mexican Democracy, Overcome by a Political Culture with Authoritarian Features

    Directory of Open Access Journals (Sweden)

    María Aidé Hernández

    2008-06-01

    Full Text Available A pesar de las transformaciones políticas que han ocurrido en México durante los últimos 20 años, la cultura política del mexicano ha dejado ver pocos avances. Actualmente siguen predominando características que no fomentan una participación autónoma y propositiva que ayude al éxito de la democracia. Entre ellas destacan el conocimiento e interés por la política; la confianza interpersonal, en las instituciones y en la democracia; la tolerancia; y la competencia subjetiva. Este panorama propicia que sigan prevaleciendo rasgos autoritarios como el clientelismo y el corporativismo, los cuales no fortalecen la democracia. Los pequeños cambios culturales se han dado en el ámbito electoral, donde no sólo hay una gran aceptación a la pluralidad y competencia entre los partidos políticos: ahora los ciudadanos consideran el voto ya no como un derecho sino como un arma política.In spite of the political transformations occurred in Mexico during the last 20 years, the Mexican citizen's political culture has shown few improvements, since certain characteristics keep on prevailing and do not encourage an autonomous participation contribuing to the success of the democratic process. Some of the most relevant advances for such process are knowledge and interest in politics; confidence in the interpersonal relationships, in institutions and in democracy; tolerance; and subjective competence. Their absence favours the prevalence of authoritarian features as clientelism and corporativism. Small cultural changes have taken place in the electoral domain though, where there is a great acceptance of plurality and competition among the political parties and citizens consider suffrage not as a right but as a political weapon.

  11. Columbia River Estuary Ecosystem Classification Ecosystem Complex

    Science.gov (United States)

    Cannon, Charles M.; Ramirez, Mary F.; Heatwole, Danelle W.; Burke, Jennifer L.; Simenstad, Charles A.; O'Connor, Jim E.; Marcoe, Keith Marcoe

    2012-01-01

    Estuarine ecosystems are controlled by a variety of processes that operate at multiple spatial and temporal scales. Understanding the hierarchical nature of these processes will aid in prioritization of restoration efforts. This hierarchical Columbia River Estuary Ecosystem Classification (henceforth "Classification") of the Columbia River estuary is a spatial database of the tidally-influenced reaches of the lower Columbia River, the tidally affected parts of its tributaries, and the landforms that make up their floodplains for the 230 kilometers between the Pacific Ocean and Bonneville Dam. This work is a collaborative effort between University of Washington School of Aquatic and Fishery Sciences (henceforth "UW"), U.S. Geological Survey (henceforth "USGS"), and the Lower Columbia Estuary Partnership (henceforth "EP"). Consideration of geomorphologic processes will improve the understanding of controlling physical factors that drive ecosystem evolution along the tidal Columbia River. The Classification is organized around six hierarchical levels, progressing from the coarsest, regional scale to the finest, localized scale: (1) Ecosystem Province; (2) Ecoregion; (3) Hydrogeomorphic Reach; (4) Ecosystem Complex; (5) Geomorphic Catena; and (6) Primary Cover Class. For Levels 4 and 5, we mapped landforms within the Holocene floodplain primarily by visual interpretation of Light Detection and Ranging (LiDAR) topography supplemented with aerial photographs, Natural Resources Conservation Service (NRCS) soils data, and historical maps. Mapped landforms are classified as to their current geomorphic function, the inferred process regime that formed them, and anthropogenic modification. Channels were classified primarily by a set of depth-based rules and geometric relationships. Classification Level 5 floodplain landforms ("geomorphic catenae") were further classified based on multivariate analysis of land-cover within the mapped landform area and attributed as "sub

  12. Columbia River Estuary Ecosystem Classification Geomorphic Catena

    Science.gov (United States)

    Cannon, Charles M.; Ramirez, Mary F.; Heatwole, Danelle W.; Burke, Jennifer L.; Simenstad, Charles A.; O'Connor, Jim E.; Marcoe, Keith

    2012-01-01

    Estuarine ecosystems are controlled by a variety of processes that operate at multiple spatial and temporal scales. Understanding the hierarchical nature of these processes will aid in prioritization of restoration efforts. This hierarchical Columbia River Estuary Ecosystem Classification (henceforth "Classification") of the Columbia River estuary is a spatial database of the tidally-influenced reaches of the lower Columbia River, the tidally affected parts of its tributaries, and the landforms that make up their floodplains for the 230 kilometers between the Pacific Ocean and Bonneville Dam. This work is a collaborative effort between University of Washington School of Aquatic and Fishery Sciences (henceforth "UW"), U.S. Geological Survey (henceforth "USGS"), and the Lower Columbia Estuary Partnership (henceforth "EP"). Consideration of geomorphologic processes will improve the understanding of controlling physical factors that drive ecosystem evolution along the tidal Columbia River. The Classification is organized around six hierarchical levels, progressing from the coarsest, regional scale to the finest, localized scale: (1) Ecosystem Province; (2) Ecoregion; (3) Hydrogeomorphic Reach; (4) Ecosystem Complex; (5) Geomorphic Catena; and (6) Primary Cover Class. For Levels 4 and 5, we mapped landforms within the Holocene floodplain primarily by visual interpretation of Light Detection and Ranging (LiDAR) topography supplemented with aerial photographs, Natural Resources Conservation Service (NRCS) soils data, and historical maps. Mapped landforms are classified as to their current geomorphic function, the inferred process regime that formed them, and anthropogenic modification. Channels were classified primarily by a set of depth-based rules and geometric relationships. Classification Level 5 floodplain landforms ("geomorphic catenae") were further classified based on multivariate analysis of land-cover within the mapped landform area and attributed as "sub

  13. Columbia River Estuary Ecosystem Classification Hydrogeomorphic Reach

    Science.gov (United States)

    Cannon, Charles M.; Ramirez, Mary F.; Heatwole, Danelle W.; Burke, Jennifer L.; Simenstad, Charles A.; O'Connor, Jim E.; Marcoe, Keith

    2012-01-01

    Estuarine ecosystems are controlled by a variety of processes that operate at multiple spatial and temporal scales. Understanding the hierarchical nature of these processes will aid in prioritization of restoration efforts. This hierarchical Columbia River Estuary Ecosystem Classification (henceforth "Classification") of the Columbia River estuary is a spatial database of the tidally-influenced reaches of the lower Columbia River, the tidally affected parts of its tributaries, and the landforms that make up their floodplains for the 230 kilometers between the Pacific Ocean and Bonneville Dam. This work is a collaborative effort between University of Washington School of Aquatic and Fishery Sciences (henceforth "UW"), U.S. Geological Survey (henceforth "USGS"), and the Lower Columbia Estuary Partnership (henceforth "EP"). Consideration of geomorphologic processes will improve the understanding of controlling physical factors that drive ecosystem evolution along the tidal Columbia River. The Classification is organized around six hierarchical levels, progressing from the coarsest, regional scale to the finest, localized scale: (1) Ecosystem Province; (2) Ecoregion; (3) Hydrogeomorphic Reach; (4) Ecosystem Complex; (5) Geomorphic Catena; and (6) Primary Cover Class. For Levels 4 and 5, we mapped landforms within the Holocene floodplain primarily by visual interpretation of Light Detection and Ranging (LiDAR) topography supplemented with aerial photographs, Natural Resources Conservation Service (NRCS) soils data, and historical maps. Mapped landforms are classified as to their current geomorphic function, the inferred process regime that formed them, and anthropogenic modification. Channels were classified primarily by a set of depth-based rules and geometric relationships. Classification Level 5 floodplain landforms ("geomorphic catenae") were further classified based on multivariate analysis of land-cover within the mapped landform area and attributed as "sub

  14. Anisotropic Ambient Volume Shading.

    Science.gov (United States)

    Ament, Marco; Dachsbacher, Carsten

    2016-01-01

    We present a novel method to compute anisotropic shading for direct volume rendering to improve the perception of the orientation and shape of surface-like structures. We determine the scale-aware anisotropy of a shading point by analyzing its ambient region. We sample adjacent points with similar scalar values to perform a principal component analysis by computing the eigenvectors and eigenvalues of the covariance matrix. In particular, we estimate the tangent directions, which serve as the tangent frame for anisotropic bidirectional reflectance distribution functions. Moreover, we exploit the ratio of the eigenvalues to measure the magnitude of the anisotropy at each shading point. Altogether, this allows us to model a data-driven, smooth transition from isotropic to strongly anisotropic volume shading. In this way, the shape of volumetric features can be enhanced significantly by aligning specular highlights along the principal direction of anisotropy. Our algorithm is independent of the transfer function, which allows us to compute all shading parameters once and store them with the data set. We integrated our method in a GPU-based volume renderer, which offers interactive control of the transfer function, light source positions, and viewpoint. Our results demonstrate the benefit of anisotropic shading for visualization to achieve data-driven local illumination for improved perception compared to isotropic shading. PMID:26529745

  15. THE CHARACTERISTIC OF MARINE ENVIRONMENT IN LINGDINGYANG ESTUARY

    Institute of Scientific and Technical Information of China (English)

    CHEN; Bing-lu

    2001-01-01

    [1]LIN Zhi-qing, 1985. The Nutrient salts in the water between Guangzhou and Humen [J] . Tropical Oceanography, 4(2):52-59. (in Chinese)[2]LUO Zhang-ren, YING Zhi-pu et al., 1992. The Harbours in South China[M]. Guangzhou: Zhongshan University Press,101-126. (in Chinese)[3]PENG Yun-hui et al., 1991. The relationship of phosphate and dissolved oxygen in Pearl River Estuary [J]. Marine Report,10(6): 25-29. (in Chinese)[4]PENG Yun-hui et al., 1994. The relationship of dissolved oxygen and nutrient salts in Pearl River Estuary[J]. Tropical Oceanography, 13(1): 96-100. (in Chinese)[5]TAN Wei-guang et al., 1993. Assessment of eutrophication of Pearl River Estuary [J] . Research & Exploration of Nanhai, (2): 17-21. (in Chinese)[6]TANG Yong-Luan, 1984. The Characteristic of the dispersion model of the substances of Pearl River Estuary and Lingding Estuary [J] . Marine Environmental Science, 3(3): 1-11.(in Chinese)[7]ZHOU Yan-xia, 1994. Analysis of the water quality of Pearl River Estuary and neighboring sea area [J]. Marine Report, 13(3):24-30. (in Chinese)[8]ZHAO Huan-ting, 1981. The topograghy of Lingding Estuary [J]. Journal of Oceanography, 3(2): 20-27. (in Chinese)

  16. Urban microbial ecology of a freshwater estuary of Lake Michigan

    Directory of Open Access Journals (Sweden)

    Jenny C. Fisher

    2015-07-01

    Full Text Available Abstract Freshwater estuaries throughout the Great Lakes region receive stormwater runoff and riverine inputs from heavily urbanized population centers. While human and animal feces contained in this runoff are often the focus of source tracking investigations, non-fecal bacterial loads from soil, aerosols, urban infrastructure, and other sources are also transported to estuaries and lakes. We quantified and characterized this non-fecal urban microbial component using bacterial 16S rRNA gene sequences from sewage, stormwater, rivers, harbor/estuary, and the lake surrounding Milwaukee, WI, USA. Bacterial communities from each of these environments had a distinctive composition, but some community members were shared among environments. We used a statistical biomarker discovery tool to identify the components of the microbial community that were most strongly associated with stormwater and sewage to describe an “urban microbial signature,” and measured the presence and relative abundance of these organisms in the rivers, estuary, and lake. This urban signature increased in magnitude in the estuary and harbor with increasing rainfall levels, and was more apparent in lake samples with closest proximity to the Milwaukee estuary. The dominant bacterial taxa in the urban signature were Acinetobacter, Aeromonas, and Pseudomonas, which are organisms associated with pipe infrastructure and soil and not typically found in pelagic freshwater environments. These taxa were highly abundant in stormwater and sewage, but sewage also contained a high abundance of Arcobacter and Trichococcus that appeared in lower abundance in stormwater outfalls and in trace amounts in aquatic environments. Urban signature organisms comprised 1.7% of estuary and harbor communities under baseflow conditions, 3.5% after rain, and >10% after a combined sewer overflow. With predicted increases in urbanization across the Great Lakes, further alteration of freshwater communities is

  17. Biogeography of dinoflagellate cysts in northwest Atlantic estuaries.

    Science.gov (United States)

    Price, Andrea M; Pospelova, Vera; Coffin, Michael R S; Latimer, James S; Chmura, Gail L

    2016-08-01

    Few biogeographic studies of dinoflagellate cysts include the near-shore estuarine environment. We determine the effect of estuary type, biogeography, and water quality on the spatial distribution of organic-walled dinoflagellate cysts from the Northeast USA (Maine to Delaware) and Canada (Prince Edward Island). A total of 69 surface sediment samples were collected from 27 estuaries, from sites with surface salinities >20. Dinoflagellate cysts were examined microscopically and compared to environmental parameters using multivariate ordination techniques. The spatial distribution of cyst taxa reflects biogeographic provinces established by other marine organisms, with Cape Cod separating the northern Acadian Province from the southern Virginian Province. Species such as Lingulodinium machaerophorum and Polysphaeridinium zoharyi were found almost exclusively in the Virginian Province, while others such as Dubridinium spp. and Islandinium? cezare were more abundant in the Acadian Province. Tidal range, sea surface temperature (SST), and sea surface salinity (SSS) are statistically significant parameters influencing cyst assemblages. Samples from the same type of estuary cluster together in canonical correspondence analysis when the estuaries are within the same biogeographic province. The large geographic extent of this study, encompassing four main estuary types (riverine, lagoon, coastal embayment, and fjord), allowed us to determine that the type of estuary has an important influence on cyst assemblages. Due to greater seasonal variations in SSTs and SSSs in estuaries compared to the open ocean, cyst assemblages show distinct latitudinal trends. The estuarine context is important for understanding present-day species distribution, the factors controlling them, and to better predict how they may change in the future. PMID:27547344

  18. Planktonic and whole system metabolism in a nutrient rich estuary (the Scheldt estuary)

    OpenAIRE

    Gazeau, Frédéric; Gattuso, Jean-Pierre; Middelburg, Jack J; Brion, Natacha; Schiettecatte, Laure-Sophie; Frankignoulle, Michel; Borges, Alberto

    2005-01-01

    Planktonic gross primary production (GPP), community respiration (CR), and nitrification (NIT) were measured monthly in the Scheldt estuary by the oxygen incubation method in 2003. No significant evolution of planktonic GPP was observed since the 1990s with high rates in the freshwater area (salinity 0; 97 6 65 mmol C m-2 d-1) decreasing seaward (22-37 mmol C m-2 d-1). A significant decrease of NIT was observed with regard to previous investigations although this process still represents up t...

  19. Seasonal patterns in the fish and crustacean community of a turbid temperate estuary (Zeeschelde Estuary, Belgium)

    OpenAIRE

    J. Maes; Taillieu, A.; Damme, P.A. van; Cottenie, K.; Ollevier, F.P.

    1998-01-01

    Fish and crustaceans were sampled for 1 year in the upper reaches of a temperate estuary characterized by high turbidity and a tidal range of up to 5 m. Samples were taken in the cooling-water circuit of the Doel Nuclear Power station (Zeeschelde, Belgium). Between July 1994 and June 1995, 55 fish species, two shrimp species and four crab species were recorded. The fish community was composed of 36 marine species, 16 freshwater species and three diadromous species. Shrimps, Gobiidae and Clupe...

  20. Maturation of the penaeid prawn Metapenaeus moyebi in Mandovi Estuary, Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Nair, S.R.S.; Achuthankutty, C.T.; Parulekar, A

    Metapenaeus moyebi contributed a good share of penaeid prawn population in the Mandovi Estuary of Goa, India throughout the year. Both males and females of this species with fully mature gonads were observed in the estuary, suggesting further...

  1. Suspended sediment fluxes in a tropical estuary, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    AnilKumar, N.; DineshKumar, P.K.; Srinivas, K.

    Annual transport processes of suspended sediments in Beypore estuary - a tropical estuary along the south west coast of India - were investigated based on time series measurements within the system. It's observed that the sediment transport...

  2. Picophytoplankton community in a tropical estuary: Detection of Prochlorococcus-like populations

    Digital Repository Service at National Institute of Oceanography (India)

    Mitbavkar, S.; Rajaneesh, K.M.; Anil, A.C.; Sundar, D.

    The influence of hydrography on the picophytoplankton (PP) abundance in estuaries was studied by sampling along a salinity gradient in an Indian estuary. Prochlorococcus-like cells were detected at salinities ranging from 0.06 to 35, which otherwise...

  3. Circulation and mixing process in Vasishta-Godavari estuary, east coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Kumar, A.R.S.; Murty, T.V.R.; Rao, M.M.M.; Rao, V.R.; Reddy, B.S.R.

    Circulation and Mixing Process in Vasishta-Godavari Estuary, have been studied by using estuarine classification model. Analysis of salinity, salt budget, diffusion coefficients and flushing times based on salinity data of Vasishta-Godavari estuary...

  4. High CO2 emissions from the tropical Godavari estuary (India) associated with monsoon river discharges

    Digital Repository Service at National Institute of Oceanography (India)

    Sarma, V.V.S.S.; Kumar, N.A.; Prasad, V.R.; Venkataramana, V.; Appalanaidu, S.; Sridevi, B.; Kumar, B.S.K.; Bharati, M.D.; Subbaiah, C.V.; Acharyya, T.; Rao, G.D.; Viswanadham, R.; Gawade, L.; Manjary, D.T.; Kumar, P.P.; Rajeev, K.; Reddy, N.P.C.; Sarma, V.V.; Kumar, M.D.; Sadhuram, Y.; Murty, T.V.R.

    Estuaries have been under sampled to establish them as sources or sinks of the atmospheric carbon dioxide. Such poor coverage is well known for tropical, particularly monsoon driven, estuaries. In an attempt to study the variability in CO sub(2...

  5. Contrasting behaviour of trace metals in the Scheldt estuary in 1978 compared to recent years

    OpenAIRE

    Nolting, R.F.; Helder, W.; De Baar, H. J. W.; Gerringa, L.J.A.

    1999-01-01

    Dissolved and particulate trace metals (Cu, Cd, Pb, Zn, Ni, Fe and Mn) measured at six stations along the Scheldt estuary in October/November 1978 are compared with more recent data. Based on Ca content in the suspended matter, three distinct geochemical regions could be distinguished: the upper estuary (salinity 1–7) dominated by fluvial mud, mid-estuary (salinity 7–17) where the composition of the suspended matter remained relatively constant, and the lower estuary where marine mud prevaile...

  6. Effect of Freshwater Influx on Phytoplankton in the Mandovi Estuary (Goa, India) during Monsoon Season: Chemotaxonomy

    OpenAIRE

    Goes, Joaquim I.; Prabhu Matondkar, S. G.; Sushma G. Parab; Helga do R. Gomes

    2013-01-01

    The Mandovi estuary is a prominent water body that runs along the west coast ofIndia. It forms an estuarine network with the adjacent Zuari estuary, connected via the Cumbharjua canal. The physico-chemical conditions seen in the Mandovi estuary are influenced by two factors: the presence of several other groups of phytoplankton, the presence of which is yet to be reported in many other tropical estuaries. It includes chrysophytes, cyanobacteria, prasinophytes, prymnesiophytes and chlorophyte...

  7. Riverbed Micromorphology of the Yangtze River Estuary, China

    Directory of Open Access Journals (Sweden)

    Shuaihu Wu

    2016-05-01

    Full Text Available Dunes are present in nearly all fluvial channels and are vital in understanding sediment transport, deposition, and flow conditions during floods of rivers and estuaries. This information is pertinent for helping developing management practices to reduce risks in river transportation and engineering. Although a few recent studies have investigated the micromorphology of a portion of the Yangtze River estuary in China, our understanding of dune development in this large estuary is incomplete. It is also poorly understood how the development and characteristics of these dunes have been associated with human activities in the upper reach of the Yangtze River and two large-scale engineering projects in the estuarine zone. This study analyzed the feature in micromorphology of the entire Yangtze River estuary bed over the past three years and assessed the morphological response of the dunes to recent human activities. In 2012, 2014, and 2015, multi-beam bathymetric measurements were conducted on the channel surface of the Yangtze River estuary. The images were analyzed to characterize the subaqueous dunes and detect their changes over time. Bottom sediment samples were collected for grain size analysis to assess the physical properties of the dunes. We found that dunes in the Yangtze River estuary can be classified in four major classes: very large dunes, large dunes, medium dunes, and small dunes. Large dunes were predominant, amounting to 51.5%. There was a large area of dunes developed in the middle and upper reaches of the Yangtze River estuary and in the Hengsha Passage. A small area of dunes was observed for the first time in the turbidity maximum zone of the Yangtze River estuary. These dunes varied from 0.12 to 3.12 m in height with a wide range of wavelength from 2.83 to 127.89 m, yielding a range in height to wavelength of 0.003–0.136. Sharp leeside slope angles suggest that the steep slopes of asymmetrical dunes in the middle and upper

  8. The chemistry of trace elements in estuaries

    International Nuclear Information System (INIS)

    Estuarine mixing processes can be generally divided into two stages. In the low-salinity region (226Ra is removed through adsorption by resuspended particles, and added through desorption from riverine suspended particles and input from the pore water. This is shown by the data collected from the Mullica River estuary. Equilibrium-speciation calculation for estuarine water predict that Al and Cu are complexed largely with organic ligands. The extent of Ni complexes with organic ligands in estuarine water depends largely on the concentration of organic ligands. Dissolved Mn and Zn do not form significant fraction of metal-organic complexes. Complexing of Fe with organics can delay precipitation of Fe-hydroxides in the course of estuarine mixing. Metal concentrations in estuarine sediments of the Mullica River are primarily controlled by physical processes. The dominant processes are resuspension and sedimentation for suspended sediments, and longitudinal mixing for bottom sediments. In suspended particles, Fe, Mn, and Zn are largely associated with amorphous material, which is clearly in contrast to those for bottom sediments in which most metals are associated with clay minerals. The coastal waters of New Jersey receive considerable Cu, Ni Mn and Zn from anthropogenic sources, and these metals are largely added in the high salinity region

  9. Aspectos computacionais do ambiente IMAGUS

    OpenAIRE

    Raabe, André Luís Alice; Giraffa, Lúcia Maria Martins

    2000-01-01

    Este artigo apresenta a descrição do ambiente IMAGUS enfatizando aspectos da implementação do protótipo do ambiente. O IMAGUS permite a construção de materiais com fins pedagógicos que se utilizam de vídeos acessado via Internet. O protótipo foi desenvolvido para validar a arquitetura proposta para o ambiente. São apresentadas as soluções a nível de modelagem e a implementação do protótipo baseada na utilização da interface Java Media Framework

  10. Attenuation of rare earth elements in a boreal estuary

    Science.gov (United States)

    Åström, Mats E.; Österholm, Peter; Gustafsson, Jon Petter; Nystrand, Miriam; Peltola, Pasi; Nordmyr, Linda; Boman, Anton

    2012-11-01

    This study focuses on attenuation of rare earth elements (REE) when a boreal creek, acidified and loaded with REE and other metals as a result of wetland drainage, empties into a brackish-water estuary (salinity extract metals from the settling material. Aluminium, Fe and REE transported by the acidic creek were extensively removed in the inner/central estuary where the acidic water was neutralised, whereas Mn was relatively persistent in solution and thus redistributed to particles and deposited further down the estuary. The REE removal was caused by several contemporary mechanisms: co-precipitation with oxyhydroxides (mainly Al but also Fe), complexation with flocculating humic substances and sorption to suspended particles. Down estuary the dissolved REE pool, remaining after removal, was fractionated: the Humic Model after revision and updating, predicted that the dissolved (humic substances. Acid sulphate soils, the source of the REE and other metals in the creek water, are widespread on coastal plains worldwide and therefore the REE attenuation patterns and mechanisms identified in the studied estuary are relevant for recognition of similar geochemical processes and conditions in a variety of coastal locations.

  11. Assessment of trophic status in Changjiang (Yangtze) River estuary

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The integrated methodology for the assessment of estuarine trophic status (ASSETS),which was extended and refined from the United States National Estuarine Eutrophication Assessment (NEEA), is a multi-parameter assessment system and has been widely used in eutrophication assessment in estuarine and coastal waters. The ASSETS was applied to evaluate the trophic status of the Changjiang (Yangtze) River estuary, one of the largest estuaries in the world. The following main results were obtained: (i) The estuarine export potential is "moderate susceptibility" due to the "moderate" dilution potential and "moderate" flushing potential; (ii) The overall human influence (OHI) index classified the impact of nutrients in the system as "high" due to the high level of nutrient discharge by the river which channels anthropogenic impacts in the catchments to the estuarine system; (iii) The overall eutrophic condition (OEC) in the estuary was classified into the "high" category due to frequent occurrence of nuisance and toxic algal blooms in the mixing and seawater zones; (iv) Since the nutrient loadings (e.g.,DIN) in the river is expected to continue to increase in the near future following the population increase and rapid economic growth throughout the drainage basin, the nutrient-related symptoms in the estuary are likely to substantially worsen, which leads to the "worsen high" category for the definition of future outlook (DFO). The combinations of the three components (i.e., OHI, OEC, and DFO) lead to an overall grade as "bad" for the trophic status in the Changjiang River estuary.

  12. Nutrient loading tot he St. Lucie Estuary, Florida

    International Nuclear Information System (INIS)

    The St. Lucie Estuary receives freshwater input from two free-flowing creeks (the Old South Fork and Ten Mile Creek) and three major drainage canals (C23, C24 and C44). The South Florida Water Management District has monitored nutrient concentrations upstream of discharge structures on the canals since the late 1970s and nutrient levels in the Estuary since 1990. Analysis of nutrient concentrations at the canal discharge structures indicates that the total nitrogen concentrations in all three canals decreased during the period from 1979 to 2000. The phosphorus concentrations in discharges from C24 and C44 were relatively steady during the same time period, while the phosphorus concentration of canal C23 increased. Variation in nutrient loading was dominated by fluctuations in the volume of canal discharges. Analysis of water quality in the estuary showed that total nitrogen and phosphorus concentrations decreased from the upper estuary to the lower estuary. Years with high maximum chlorophyll a concentrations tended to occur in the years in which nutrient loading from the three canals was high. (author)

  13. Metals in sediments and benthic organisms in the Mersey estuary

    Science.gov (United States)

    Langston, W. J.

    1986-08-01

    Concentrations of twelve metals were determined in sediments, seaweed ( Fucus vesiculosus), winkles ( Littorina littorea), polychaetes ( Nereis diversicolor), suspension feeding bivalves ( Mytilus edulis, Cerastoderma edule) and deposit feeding bivalves ( Macoma balthica, Scrobicularia plana) collected from the Mersey estuary between April 1980 and June 1984. Sediments and organisms in the Mersey are moderately contaminated with most of the metals measured, but mercury concentrations are consistently higher than in other United Kingdom estuaries. Comparisons with other sites in the North West of England indicate that mercury residues in organisms, though primarily dependent on sediment concentrations, are also influenced by complexation with particulate organic matter which reduces the availability of mercury. The biological availability of arsenic in Mersey sediments is similarly influenced by complexation with iron oxyhydroxides. Nereis diversicolor and Macoma balthica are the most suitable indicator species in terms of abundance and widespread distribution along the estuary, and, for the majority of metals, tissue concentrations increase upstream, reflecting corresponding gradients in sediment contamination. However mid-estuarine peaks for tin, chromium copper and nickel in Nereis indicate more localised inputs to the estuary. Correlations between lead in sediments and organisms are poor; it is suggested that hydrophilic alkyl lead compounds may be the predominant biologically available forms. Progressive reductions in mercury contamination in sediments and mercury and lead in organisms have occurred in recent years, which coincide with efforts to reduce inputs of these metals to teh Mersey estuary.

  14. Dissolved organic carbon in the freshwater tidal reaches of the Schelde estuary

    DEFF Research Database (Denmark)

    Muylaert, K.; Dasseville, R.; De Brabandere, Loreto;

    2005-01-01

    To unravel the factors that regulate DOC dynamics in the freshwater tidal reaches of the Schelde estuary, DOC concentration and biodegradability were monitored in the upper Schelde estuary and its major tributaries. Although the Schelde estuary possesses a densely populated and industrialized cat...

  15. Eco-Morphological Problems in the Yangtze Estuary and the Western Scheldt

    NARCIS (Netherlands)

    Vriend, de H.J.; Wang, Z.B.; Ysebaert, T.; Herman, P.M.J.; Ding, P.X.

    2011-01-01

    This paper compares the Yangtze Estuary in China and the Western Scheldt Estuary in The Netherlands by their morphodynamic and ecological systems, their engineering works and estuarine management issues, and the major challenges in studying them. Physically speaking, the two estuaries are very diffe

  16. Distribution and sources of particulate organic matter in the Indian monsoonal estuaries during monsoon

    Digital Repository Service at National Institute of Oceanography (India)

    Sarma, V.V.S.S.; Krishna, M.S.; Prasad, V.R.; Kumar, B.S.K.; Naidu, S.A.; Rao, G.D.; Viswanadham, R.; Sridevi, T.; Kumar, P.P.; Reddy, N.P.C.

    in estuaries with deeper photic zone than other estuaries receiving higher suspended matter. The delta13CPOC and delta15CPN data suggest that relatively higher delta13CPOC (-27.9 to -22.6‰) and lower delta15CPN (0.7 to 5.8‰) were noticed in the estuaries...

  17. Ambient and potential denitrification rates in marsh soils of Northeast Creek and Bass Harbor Marsh watersheds, Mount Desert Island, Maine

    Science.gov (United States)

    Huntington, Thomas G.; Culbertson, Charles W.; Duff, John H.

    2012-01-01

    Nutrient enrichment from atmospheric deposition, agricultural activities, wildlife, and domestic sources is a concern at Acadia National Park on Mount Desert Island, Maine, because of the potential problems of degradation of water quality and eutrophication in estuaries. Degradation of water quality has been observed at Bass Harbor Marsh estuary in the park but only minimally in Northeast Creek estuary. Previous studies at Acadia National Park have estimated nutrient inputs to estuaries from atmospheric deposition and surface-water runoff, and have identified shallow groundwater as an additional potential source of nutrients. Previous studies at Acadia National Park have assumed that a certain fraction of the nitrogen input was removed through microbial denitrification, but rates of denitrification (natural or maximum potential) in marsh soils have not been determined. The U.S. Geological Survey, in cooperation with Acadia National Park, measured in-place denitrification rates in marsh soils in Northeast Creek and in Bass Harbor Marsh watersheds during summer 2008 and summer 2009. Denitrification was measured under ambient conditions as well as after additions of inorganic nitrogen and glucose. In-place denitrification rates under ambient conditions were similar to those reported for other coastal wetlands, although they were generally lower than those reported for salt marshes having high ambient concentrations of nitrate (NO3). Denitrification rates generally increased by at least an order of magnitude following NO3 additions, with or without glucose (as the carbohydrate) additions, compared with the ambient treatments that received no nutrient additions. The treatment that added both glucose and NO3 resulted in a variety of denitrification responses when compared with the addition of NO3 alone. In most cases, the addition of glucose to a given rate of NO3 addition resulted in higher rates of denitrification. These variable responses indicate that the amount of

  18. Effects of heavy metal contamination on the macrobenthic fauna in estuaries: The case of the Seine estuary

    Energy Technology Data Exchange (ETDEWEB)

    Dauvin, Jean-Claude [Station Marine de Wimereux, Universite des Sciences et Technologies de Lille, CNRS FRE 2816 ELICO - Ecosystemes Littoraux et Cotiers, 28, Avenue Foch, BP 80, F-62930 Wimereux (France)], E-mail: jean-claude.dauvin@univ-lille1.fr

    2008-07-01

    Heavy metal contamination levels are generally higher in estuaries than in the open sea. Some estuaries, the Seine estuary for example, have particularly high pollution levels of metals, yet continue to support a very high benthic biomass and remain quite productive. Measurements of sediment contamination are highly variable due to diverse chemical analysis methods, sediments origin and sources of contaminants found in the estuaries. Salinity appears to be the principal factor controlling contaminant distribution in the sediment and the overlying and/or interstitial waters; it also affects the bioavailability of contaminants in estuarine sediments. Of course, the response to contaminants varies greatly among species and assemblages. Trace metals explain only a small part of the variation in benthic community structure. Some species, such as the shrimp Crangon crangon, appears vulnerable to metal pollution, while other species, such as Scrobicularia plana, are able to tolerate quite high levels of cadmium in their tissue. This paper demonstrates the wide variability of benthic responses to contamination, which is probably due to the high spatio-temporal heterogeneity of the estuary. To reduce the problems due the heterogeneity and variability observed to date in the available results, it will be necessary to encourage integrated estuarine studies, in which sedimentologists, chemists, and biologists work together on the same campaigns at the same sites.

  19. Effects of heavy metal contamination on the macrobenthic fauna in estuaries: the case of the Seine estuary.

    Science.gov (United States)

    Dauvin, Jean-Claude

    2008-01-01

    Heavy metal contamination levels are generally higher in estuaries than in the open sea. Some estuaries, the Seine estuary for example, have particularly high pollution levels of metals, yet continue to support a very high benthic biomass and remain quite productive. Measurements of sediment contamination are highly variable due to diverse chemical analysis methods, sediments origin and sources of contaminants found in the estuaries. Salinity appears to be the principal factor controlling contaminant distribution in the sediment and the overlying and/or interstitial waters; it also affects the bioavailability of contaminants in estuarine sediments. Of course, the response to contaminants varies greatly among species and assemblages. Trace metals explain only a small part of the variation in benthic community structure. Some species, such as the shrimp Crangon crangon, appears vulnerable to metal pollution, while other species, such as Scrobicularia plana, are able to tolerate quite high levels of cadmium in their tissue. This paper demonstrates the wide variability of benthic responses to contamination, which is probably due to the high spatio-temporal heterogeneity of the estuary. To reduce the problems due the heterogeneity and variability observed to date in the available results, it will be necessary to encourage integrated estuarine studies, in which sedimentologists, chemists, and biologists work together on the same campaigns at the same sites. PMID:18045624

  20. Effects of heavy metal contamination on the macrobenthic fauna in estuaries: The case of the Seine estuary

    International Nuclear Information System (INIS)

    Heavy metal contamination levels are generally higher in estuaries than in the open sea. Some estuaries, the Seine estuary for example, have particularly high pollution levels of metals, yet continue to support a very high benthic biomass and remain quite productive. Measurements of sediment contamination are highly variable due to diverse chemical analysis methods, sediments origin and sources of contaminants found in the estuaries. Salinity appears to be the principal factor controlling contaminant distribution in the sediment and the overlying and/or interstitial waters; it also affects the bioavailability of contaminants in estuarine sediments. Of course, the response to contaminants varies greatly among species and assemblages. Trace metals explain only a small part of the variation in benthic community structure. Some species, such as the shrimp Crangon crangon, appears vulnerable to metal pollution, while other species, such as Scrobicularia plana, are able to tolerate quite high levels of cadmium in their tissue. This paper demonstrates the wide variability of benthic responses to contamination, which is probably due to the high spatio-temporal heterogeneity of the estuary. To reduce the problems due the heterogeneity and variability observed to date in the available results, it will be necessary to encourage integrated estuarine studies, in which sedimentologists, chemists, and biologists work together on the same campaigns at the same sites

  1. Waterfowl migration and distribution in North West estuaries. V. 2

    International Nuclear Information System (INIS)

    Waterfowl populations may be affected by the proposed tidal barrage across the Mersey. A study was performed with three objectives: (1) to evaluate the patterns of usage of the intertidal flats of the Mersey estuary by waders and wildfowl and to establish which are the preferred areas; (2) to identify the places of origin and movement patterns of the populations of waders and wildfowl that visit the Mersey estuary; and (3) to evaluate evidence regarding the capacity of British estuaries to absorb waders and wildfowl populations which might be displaced by a Mersey Barrage. The text and tables of results of this study have already been presented in Volume 1. Volume 2 contains the figures describing the results (U.K)

  2. Cadmium in the Amazonian Guajara Estuary: Distribution and remobilization

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, S.F. [Instituto de Quimica, Departamento de Geoquimica, Universidade Federal Fluminense (Brazil)]. E-mail: nascimento@lisa.univ-paris12.fr; Kurzweil, H. [Institut fuer Petrologie, Universitaet Wien (Austria); Wruss, W. [Institut fuer Chemische Technologie anorganischer Stoffe, Technische Univesitaet Wien (Austria); Fenzl, N. [Nucleo de Altos Estudos Amazonicos, Universidade Federal do Para (Brazil)

    2006-03-15

    Extremely high total cadmium concentrations (average about 500 mg/kg) together with very small (average of 1.1 {mu}g/l) dissolved available cadmium have been found in the more acidic deeper layers of the bottom sediments of the Brazilian Amazonian Guajara Estuary. The paper shows that climatic changes and the periodic input of the Atlantic waters into the Estuary appear to have no direct influence on annual average total cadmium concentration, but they affect accumulation, distribution and remobilization of cadmium in different ways during the rainy season (February/March) and the dry season (November/December). Even if only a very small part of the total Cd is available, the concentrations of dissolved Cd in the Estuary are still high enough to cause environmental concern, if compared with concentrations in natural freshwater ecosystems. - Distribution and remobilization of cadmium is affected differently by season.

  3. Radium isotopes in the Orinoco estuary and Eastern Caribbean Sea

    International Nuclear Information System (INIS)

    Radium isotopes provide a means of identifying the source of freshened waters in the ocean and determining the time elapsed since these waters were in the estuary. The authors present evidence that during April, waters from the Amazon mixing zone pass within 50 km of the mouth of the Orinoco River. These Amazon waters are characterized by a lower 228Ra/226Ra activity ratio (AR) than are waters from the Orinoco at similar salinities. During autumn, the increased discharge of the Orinoco displaces the freshened Amazon waters seaward, yet the two can be distinguished clearly. Within the Caribbean Sea, waters of Orinoco origin carry a characteristic radium signature including excess activities of 224Ra. This isotope may be used to estimate the time elapsed since the waters were removed from contact with sediments. Current speeds based on 224Ra dating ranged from 15 to 33 cm/s during April. The radium isotopes also provide an assessment of sediment mixing in the estuary. During low discharge (April), considerable mixing of older sediment by physical or biological processes or dredging maintained high activities of 228Ra in the estuary and produced the highest 228Ra/226Ra AR's yet measured in any estuary. During high discharge (September), a large fraction of the 228Ra was derived from desorption from fresh sediment rather than mixing of older sediments. Activities of 224Ra were high in the estuary during both high and low discharge, indicating that considerable mixing of recently introduced sediment must occur during each period. During April, 224Ra and 228Ra activities in the water were about equal, indicating that most of the sediment being resuspended had been stored in the estuary long enough to reestablish radioactive equilibrium in the 232Th decay series (i.e., 20 years). 19 refs., 11 figs., 3 tabs

  4. Risky behavior, personality traits and road accidents among university students Comportamiento de riesgo, rasgos de personalidad y accidentes de carretera en estudiantes universitarios.

    Directory of Open Access Journals (Sweden)

    Aristides I. Ferreira

    2009-06-01

    Full Text Available The personality traits that mediate risky driving and accidents among university students drivers were investigated. Study 1 (N=132 tested for the relation between risky behaviors and personality (16PF-5 second order dimensions. Three factors were extracted concerning risky driving: driving errors of commission, distraction, and driving errors of omission. Individuals with low self-control and high levels of anxiety were more prone to commit distractive behavior and driving errors of omission. Low self-control and high independence levels were associated with driving errors of commission. In study 2 (N=540, we tested if the number of road accidents for which an individual has been responsible was related to risky driving behavior. Drivers who committed more accidents presented higher scores in three new risky driving factors obtained: reckless driving, impaired concentration and division of attention.

    Key words: Risky driving, personality, accidents, behavior.
    En este estudio se investigaron los rasgos de personalidad relacionados con la conducción de riesgo y los accidentes en estudiantes universitarios. El primer estudio (N=132 evaluó la relación entre los comportamientos de riesgo y la personalidad (16PF-5 dimensiones de segundo orden. Tres factores fueron extraídos en relación con la conducción de riesgo: cometer errores de conducción, distracción, errores de omisión en la conducción. Los individuos con bajo autocontrol y altos niveles de ansiedad eran más propensos a tener comportamientos distractores y cometer errores de omisión en la conducción. Mientras que sujetos con bajo autocontrol y altos niveles de independencia se asociaron con el factor cometer errores de conducción. En el segundo estudio (N=540 evaluamos si el número de accidentes de tráfico, de los que una persona ha sido responsable, está relacionado con el comportamiento de riesgo en la conducción. Los resultados muestran que los conductores

  5. Relación de aptitudes musicales, intelectuales y rasgos de personalidad e identificación del talento musical en escolares de diez a doce años

    OpenAIRE

    Lázaro Tortosa, Francisco Rafael

    2015-01-01

    La presente investigación surge de las reflexiones como docente de Educación Primaria sobre la calidad del desarrollo en el aula de las capacidades musicales, intelectuales, rasgos de personalidad en los escolares y sobre la jerarquización de las áreas contempladas en nuestro sistema educativo que no se corresponde con la pretendida “educación integral”. La fundamentación teórica comprende tres capítulos (aptitudes intelectuales, aptitudes musicales y personalidad) organizados bajo el mism...

  6. Estudio de la relación entre la variabilidad anatómica regional del cerebro medida con RM 3-D y los estilos cognitivos y rasgos de la personalidad

    OpenAIRE

    López Sala, Anna

    2012-01-01

    El proceso de hominización probablemente ha implicado una serie de cambios morfológicos cerebrales. El grado de desarrollo anatómico de regiones cerebrales funcionalmente relevantes, caracterizadas por su gran variabilidad interindividual y por la existencia de una marcada asimetría hemisférica, podría estar relacionado con las diferencias individuales en los estilos cognitivos y rasgos de la personalidad. Hay numerosos estudios que exponen las diferentes asimetrías morfológicas hemisféricas ...

  7. Rasgos de personalidad, edad, cultura y restricciones hídricas y dietéticas en pacientes en hemodiálisis Personality traits, age, culture and hydric and dietetic restrictions in patients undergoing haemodialysis

    OpenAIRE

    Ana María Ruiz Vaca; Victoria Eugenia Muñoz García; José Luis García Vega; Nayet Mohamed Maanan; Juana García Criado; Aziza Bagdad Abselam

    2011-01-01

    Queda mucho por investigar y comprender alrededor de la interacción entre lo físico y lo mental. Los pacientes sometidos a hemodiálisis debido a su enfermedad, deben cumplir una serie de normas dietéticas, de cuidado de su acceso vascular, etc. Pensamos que los rasgos de la personalidad, la edad, la cultura, pueden influir en la aceptación de la enfermedad de nuestros pacientes renales en tratamiento sustitutivo con hemodiálisis, y por lo consiguiente en el cumplimiento de las normas dietétic...

  8. Descripción del rendimiento cognitivo y rasgos de personalidad de pacientes con fibromialgia: relación del rendimiento cognitivo con la percepción de dolor, sintomatología depresiva e impacto de la enfermedad.

    OpenAIRE

    Virumbrales Cancio, Montserrat

    2009-01-01

    La fibromialgia (FM) es una enfermedad de etiología desconocida, que se caracteriza por la presencia de dolor musculoesquelético difuso crónico de más de tres meses de evolución, acompañado generalmente de fatiga, rigidez de intensidad variable y un amplio rango de otros síntomas. Con frecuencia los pacientes con FM suelen referir, quejas sobre su rendimiento cognitivo, manifestando principalmetne dificultad para concentrarse y pérdida de memoria. Con la intención de conocer los rasgos de ...

  9. Prácticas de crianza y su relación con rasgos resilientes de niños y niñas / Practices of parenting and the relationship resilient traits of the children

    OpenAIRE

    Aguirre Forero, Ana Mireya

    2010-01-01

    En la investigación se analizan las relaciones existentes entre rasgos resilientes: autoconcepto y autoevaluación, autoestima, autonomía, empatía, humor y creatividad, con las categorías de las prácticas de crianza en las dimensiones de apoyo afectivo y regulación de comportamiento tales como: expresiones de afecto, orientación positiva, involucramiento, prácticas de cuidado, sensibilización e inducción. Con el fin de determinar relaciones existentes entre ellas, y encontrar prácticas de cria...

  10. Research, Monitoring, and Evaluation for the Federal Columbia River Estuary Program

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Gary E.; Diefenderfer, Heida L.; Ebberts, Blaine D.; Tortorici, Cathy; Yerxa, Tracey; Leary, J.; Skalski, John R.

    2008-02-05

    The purpose ofthis document is to describe research, monitoring, and evaluation (RME) for the Federal Columbia River Estuary Program. The intent of this RME effort is to provide data and information to evaluate progress toward meeting program goals and objectives and support decision-making in the Estuary Program. The goal of the Estuary Program is to understand, conserve, and restore the estuary ecosystem to improve the performance of listed salmonid populations. The Estuary Program has five general objectives, designed to fulfill the program goal, as follows. 1. Understand the primary stressors affecting ecosystem controlling factors, such as ocean conditions and invasive species. 2. Conserve and restore factors controlling ecosystem structures and processes, such as hydrodynamics and water quality. 3. Increase the quantity and quality of ecosystem structures, i.e., habitats, juvenile salmonids use during migration through the estuary. 4. Maintain the food web to benefit salmonid performance. 5. Improve salmonid performance in terms of life history diversity, foraging success, growth, and survival. The goal of estuary RME is to provide pertinent and timely research and monitoring information to planners, implementers, and managers of the Estuary Program. In conclusion, the estuary RME effort is designed to meet the research and monitoring needs of the estuary Program using an adaptive management process. Estuary RME's success and usefulness will depend on the actual conduct of adaptive management, as embodied in the objectives, implrementation, data, reporting, and synthesis, evaluation, and decision-making described herein.

  11. Predicting fish community properties within estuaries: Influence of habitat type and other environmental features

    Science.gov (United States)

    França, Susana; Vasconcelos, Rita P.; Fonseca, Vanessa F.; Tanner, Susanne E.; Reis-Santos, Patrick; Costa, Maria José; Cabral, Henrique N.

    2012-07-01

    Statistical models predicting species distributions are essential not only to increase knowledge on species but for their application in conservation and ecologically-based management. The variation of fish species richness and abundance in the most representative habitats (saltmarsh, mudflat and subtidal) in five estuaries along the Portuguese coast was analysed through seasonal sampling surveys in 2009. Generalized additive models (GAM) were developed to describe the variation of species richness and abundances with a set of geomorphologic, hydrologic and environmental characteristics from the sampled estuaries and habitats. GAM were chosen as the complex interactions dominating these ecosystems and species distribution are non-linear. Final models built for each estuary and for all estuaries together performed well during the calibration phase and also during the validation phase, where an unused data sub-set from each estuary was used. There was not a similar combination of variables retained by the models for the studied estuaries but factors such as the area of the habitat, the distance to estuary mouth, percentage of mud in the sediment and depth were commonly retained. The partial effect of these predictor variables on the variation of species richness and abundance in the estuaries varied markedly and the importance of preserving the heterogeneity of habitats within estuaries was highlighted. Models for each individual estuary performed better than models for estuaries combined. Predictive models could be useful as a preliminary tool to prepare long-term conservation plans at different scales.

  12. Ambiente juvenil: discurso ambiental entre jóvenes universitarios

    OpenAIRE

    Quinn-Anderson, William C.

    2008-01-01

    Esta tesis pretende hacer una aportación al conocimiento del medio ambiente del occidente de México, específicamente de la zona metropolitana de Guadalajara, a partir del estudio de la cultura ambiental manifestada en el discurso de los jóvenes universitarios del ITESO. La apuesta es que puede ser provechoso considerar dentro del concepto de “medio ambiente” no solamente componentes bióticos y abióticos, sino también elementos socioculturales como cultura y significado. Es evidente que hay in...

  13. Distribution of tributyltin (TBT) in the Mandovi estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Bhosle, N.B.

    is known about the levels of onrganotins in Indian waters, sediments, and animals. Mandovi estuary, Goa, India is one of the few marine areas of the country where some information on TBT levels is available. An attempt to summarise what is known about TBT...

  14. Maturation of Metapenaeus moyebi (Kishinouye) in Goa estuaries

    Digital Repository Service at National Institute of Oceanography (India)

    Nair, S.R.S.; Achuthankutty, C.T.; Parulekar, A

    An assessment of the stake net fishery in the Mandovi and Zuari estuaries of Goa revealed that Metapenaeus moyebi, a penaeid prawn hitherto rarely recorded in Indian waters, formed a good percentage of the estuarine prawn fishery of Goa. At one...

  15. Estuaries May Face Increased Parasitism as Sea Levels Rise

    Science.gov (United States)

    Wendel, JoAnna

    2014-12-01

    Invertebrates in estuaries could be at a greater risk of parasitism as climate change causes sea levels to rise. A new paper published 8 December in Proceedings of the National Academy of Sciences of the United States of America (doi:10.1073/pnas.1416747111) describes how rapid sea level rise in the Holocene affected the population of parasitic flatworms called trematodes.

  16. A new analytical framework for tidal propagation in estuaries

    NARCIS (Netherlands)

    Cai, H.

    2014-01-01

    The ultimate aim of this thesis is to enhance our understanding of tidal wave propagation in convergent alluvial estuaries (of infinite length). In the process, a new analytical model has been developed as a function of externally defined dimensionless parameters describing friction, channel converg

  17. Environmental flow assessments in estuaries related to preference of phytoplankton

    OpenAIRE

    Z. F. Yang; Sun, T; Zhao, R.

    2014-01-01

    We developed an approach to assess environmental flows in estuaries related to preference of phytoplankton considering the complex relationship between hydrological modification and biomass in ecosystems. As a first step, a relationship was established between biomass requirements for organisms of primary and higher nutritional levels based on the principle of nutritional energy flow of ecosystem. Then, diagnostic pigments were employed to represent phytopl...

  18. Time scales in Galveston Bay: An unsteady estuary

    Science.gov (United States)

    Rayson, Matthew D.; Gross, Edward S.; Hetland, Robert D.; Fringer, Oliver B.

    2016-04-01

    Estuarine time scales including the turnover, particle e-folding time, the age (calculated with a passive tracer), and residence time (calculated with Lagrangian particles) were computed using a three-dimensional hydrodynamic model of Galveston Bay, a low-flow, partially stratified estuary. Time scales were computed during a time period when river flow varied by several orders of magnitude and all time scales therefore exhibited significant temporal variability because of the unsteadiness of the system. The spatial distributions of age and residence time were qualitatively similar and increased from 15 days in a shipping channel to >45 days in the upper estuary. Volume-averaged age and residence time decreased during high-flow conditions. Bulk time scales, including the freshwater and salinity turnover times, were far more variable due to the changing river discharge and salt flux through the estuary mouth. A criterion for calculating a suitable averaging time is discussed to satisfy a steady state assumption and to estimate a more representative bulk time scale. When scaled with a freshwater advective time, all time scales were approximately equal to the advective time scale during high-flow conditions and many times higher during low-flow conditions. The mean age, Lagrangian residence, and flushing times exhibited a relationship that was weakly dependent on the freshwater advective time scale demonstrating predictability even in an unsteady, realistic estuary.

  19. Man's Impact on the Environment: The Estuary as an Ecosystem.

    Science.gov (United States)

    Brevard County School Board, Cocoa, FL.

    This environmental education guide focuses on man's impact on the estuary. The program contained in the guide is developed around the following nine questions: (1) What is a definition of the ecosystem being investigated?; (2) What are some of the biotic and abiotic features of the ecosystem and how do these features interrelate?; (3) Where are…

  20. Contaminants of emerging concern in a large temperate estuary.

    Science.gov (United States)

    Meador, James P; Yeh, Andrew; Young, Graham; Gallagher, Evan P

    2016-06-01

    This study was designed to assess the occurrence and concentrations of a broad range of contaminants of emerging concern (CECs) from three local estuaries within a large estuarine ecosystem. In addition to effluent from two wastewater treatment plants (WWTP), we sampled water and whole-body juvenile Chinook salmon (Oncorhynchus tshawytscha) and Pacific staghorn sculpin (Leptocottus armatus) in estuaries receiving effluent. We analyzed these matrices for 150 compounds, which included pharmaceuticals, personal care products (PPCPs), and several industrial compounds. Collectively, we detected 81 analytes in effluent, 25 analytes in estuary water, and 42 analytes in fish tissue. A number of compounds, including sertraline, triclosan, estrone, fluoxetine, metformin, and nonylphenol were detected in water and tissue at concentrations that may cause adverse effects in fish. Interestingly, 29 CEC analytes were detected in effluent and fish tissue, but not in estuarine waters, indicating a high potential for bioaccumulation for these compounds. Although concentrations of most detected analytes were present at relatively low concentrations, our analysis revealed that overall CEC inputs to each estuary amount to several kilograms of these compounds per day. This study is unique because we report on CEC concentrations in estuarine waters and whole-body fish, which are both uncommon in the literature. A noteworthy finding was the preferential bioaccumulation of CECs in free-ranging juvenile Chinook salmon relative to staghorn sculpin, a benthic species with relatively high site fidelity. PMID:26907702

  1. A model of nematode dynamics in the Westerschelde estuary

    NARCIS (Netherlands)

    Li, J.; Vincx, M.; Herman, P.M.J.

    1996-01-01

    We developed a time dynamic model to investigate the temporal dynamics of nematode community in the brackish zone of the Westerschelde Estuary. The biomass of four nematode feeding groups observed from March 1991 to February 1992 is used to calibrate the model. Using environmental data as the input,

  2. Sediment transport investigations in Hugli estuary using radiotracer technique

    International Nuclear Information System (INIS)

    This paper describes sediment transport investigations carried out at two different locations in Hugli estuary along the shipping channel leading to Haldia Dock Complex of the Kolkata Port Trust, Kolkata. The objectives of these investigations were to evaluate the suitability of the proposed dumping sites for optimizing the dredging operation and implementing the recommendations of the River Regulatory Measures, Kolkata Port Trust, Kolkata

  3. Production and consumption of biological particles in temperate tidal estuaries

    NARCIS (Netherlands)

    Heip, C.H.R.; Goosen, N.K.; Herman, P.M.J.; Kromkamp, J.C.; Middelburg, J.J.; Soetaert, K.E.R.

    1995-01-01

    The question is reviewed whether a balance exists between production and consumption of biological particles in temperate tidal estuaries and what the relationships are between the magnitude of production and consumption processes and system carbon metabolism. The production terms considered are pri

  4. Behaviour of aluminium, silicon and iron in Tapi Estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Sharma, P.; Zingde, M.D.

    of pH, dissolved oxygen, NO sub(3) sup(-) -N and NH sub(4) sup(+) -N which were also suggestive of some biogenic removal of dissolved Fe. In the estuary however, dissolved Fe was randomly distributed and poorly correlated with chlorinity as well as pH....

  5. Organic carbon in the sediments of Mandovi estuary, Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Alagarsamy, R.

    Total organic carbon (TOC) in surficial sediments in Mandovi Estuary, Goa, India varies widely from 0.1 to 3% (av. 1.05%). Highest values of TOC (2.4-3%) lie close to the mouth region and indicate no definite trend in its variation in the estuarine...

  6. Revised predictive equations for salt intrusion modelling in estuaries

    Directory of Open Access Journals (Sweden)

    J. I. A. Gisen

    2015-01-01

    Full Text Available For one-dimensional salt intrusion models to be predictive, we need predictive equations to link model parameters to observable hydraulic and geometric variables. The one-dimensional model of Savenije (1993b made use of predictive equation for the Van der Burgh coefficient K and the dispersion at the seaward boundary D0. Here we have improved these equations by using an expanded database, including new previously un-surveyed estuaries. Furthermore, we derived a revised predictive equation for the dispersion at tidal average (TA condition and with the boundary situated at the well identifiable inflection point where the estuary changes from wave-dominated to tide-dominated geometry. We used 89 salinity profiles in 30 estuaries (including 7 recently studied estuaries in Malaysia, and empirically derived a range of equations using various combinations of dimensionless parameters. We split our data in two separated datasets: (1 with more reliable data for calibration, and (2 with less reliable data for validation. The dimensionless parameters that gave the best performance depended on the geometry, tidal strength, friction and the Richardson Number. The limitation of the equations is that the friction is generally unknown. In order to overcome this problem, a coupling has been made with the analytical hydraulic model of Cai et al. (2012, which makes use of observed tidal damping and by which the friction can be determined.

  7. Revised predictive equations for salt intrusion modelling in estuaries

    Directory of Open Access Journals (Sweden)

    J. I. A. Gisen

    2015-06-01

    Full Text Available For one-dimensional salt intrusion models to be predictive, we need predictive equations to link model parameters to observable hydraulic and geometric variables. The one-dimensional model of Savenije (1993b made use of predictive equations for the Van der Burgh coefficient $K$ and the dispersion at the seaward boundary D0. Here we have improved these equations by using an expanded database, including new previously un-surveyed estuaries. Furthermore, we derived a revised predictive equation for the dispersion at tidal average condition and with the boundary situated at the well identifiable inflection point where the estuary changes from wave-dominated to tide-dominated geometry. We used 89 salinity profiles in 30 estuaries (including seven recently studied estuaries in Malaysia, and empirically derived a range of equations using various combinations of dimensionless parameters. We split our data in two separated data sets: (1 with more reliable data for calibration, and (2 with less reliable data for validation. The dimensionless parameters that gave the best performance depended on the geometry, tidal strength, friction and the Richardson number. The limitation of the equations is that the friction is generally unknown. In order to overcome this problem, a coupling has been made with the analytical hydraulic model of Cai et al. (2012, which makes use of observed tidal damping and by which the friction can be determined.

  8. Flushing characteristics of Amba river estuary, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    DineshKumar, P.K.; Sarma, R.V.; Josanto, V.

    of 22 tidal cycles for neap, 6 to 7 tidal cycles for spring and dry weather flushing time of 45 tidal cycles for neap, 6 to 7 tidal cycles for spring based on modified tidal prism method indicated that the load retained in the estuary after infinite...

  9. Water and suspended sediment dynamics in the Sungai Selangor estuary

    International Nuclear Information System (INIS)

    Observations of salinity, temperature, suspended sediment concentration (SSC) and tidal current velocity were made in the lower and along the longitudinal axis sungai Selangor estuary over near-spring cycles. The variations of these parameters at the measurement stations and along the channel are presented to illustrate the water and sediment dynamics in the estuary. The results shows that the Sungai Selangor estuary changes from a partially-mixed type during neaps to a well-mixed one during springs. promoted by stronger tidal energy during the higher tidal ranges. The strong neap density stratification is also promoted by the high river discharges during the measurement period maximum concentration of suspended sediment 2000 mg,'/) occurs during maximum current velocities both during flood and ebb. The maximum salinity was achieved during high water slack but the salt water was totally flushed out of estuary during low water springs. The longitudinal axis measurement indicates that a partially-developed zone of turbidity maximum with a sediment concentration over 1000 mg/l was observed at the limit of salt water intrusion in salinity range less than 1 ppt. Tidal pumping as oppose to the estuarine circulation is the more dominant factor in the maximum formation as the salt water is totally excluded at low water. (author)

  10. Environmental features and macrofauna of Kahana Estuary, Oahu, Hawaii

    Science.gov (United States)

    Maciolek, J.A.; Timbol, A.S.

    1981-01-01

    Lack of ecological information on Hawaiian estuaries prompted an intensive 2-year study of a small (5.7 ha) stream-mouth estuary on windward Oahu. Water quality and macrofauna were sampled weekly at seven stations. The water mass was strongly stratified vertically except during freshets. Average values for water column temperature and bottom salinity were 23.2°C and 12‰ at the head to 28.3°C and 28‰ at the mouth. Dissolved oxygen saturation in the water column varied from about 50% at night to 140% in the afternoon. Usually, bottom waters were 3–6°C warmer than surface waters and sometimes showed severe oxygen depletion.Macrofauna, collected primarily by seining, consisted mainly of decapod crustaceans (four species of crabs, seven species of shrimps) and fishes (24 species). Other typical estuarine taxons (mollusks, barnacles, polychaetes) were scarce or absent. Diversity increased seaward from 14 species near the estuary head to 29 species near the mouth. Three species of crustaceans and six of fishes were captured at all stations. Most abundant were the native prawn, Macrobrachium grandimanus, and mullet, Mugil cephalus. Perennially resident adults occurred among crustaceans and gobioid fishes; most other fishes were present as juveniles and sporadic adults. Comparisons with other data suggest that more than 50 species of native fishes may occur in Hawaiian estuaries, and that estuarine macrofaunal diversity on oceanic islands is much lower than on continents at similar latitudes.

  11. Laboratory Investigations on Estuary Salinity Mixing: Preliminary Analysis

    Directory of Open Access Journals (Sweden)

    F. H. Nuryazmeen

    2014-05-01

    Full Text Available Estuaries are bodies of water along the coasts that are formed when fresh water from rivers flows into and mixes with salt water from the ocean. The estuaries serve as a habitat to some aquatic lives, including mangroves. Human-induced activities such as dredging of shipping lanes along the bottom estuarine, the disposal of industrial wastes into the water system and shoreline development influence estuarine dynamics which include mixing process. These activities might contribute to salinity changes and further adversely affect the estuarine ecosystem. In order to study at the characteristics of the mixing between salt water (estuary and freshwater (river, a preliminary investigation had been done in the laboratory. Fresh water was released from one end of the flume and overflowing at weir at the other end. Meanwhile, salt water was represented by the red dye tracer released through a weir and intruded upstream as a gravity current. The isohalines are plotted to see the salinity patterns. Besides, to examine the spatial and temporal salinity profiles along the laboratory investigations, the plotted graphs have been made. The results show that the changes in salinity level along the flume due to mixing between fresh water and salt water. This showed typical salt-wedge estuary characteristics.

  12. Biogeochemistry of Nutrient Elements in the Changjiang (Yangtze River) Estuary

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Based on the biogeochemical studies on nutrient elements in the Changjiang estuary,the main results and recent progresses are reviewed in this paper, such as the nutrient fluxes into the sea, the mixing behaviors, the distribution characteristics and transportation as well as the biogeochemical behaviors of nutrients in the plume frontal region. The exploring directions and research emphases in the future are proposed.

  13. Phytoplankton diversity and primary production in Poonthura estuary, south Kerala

    OpenAIRE

    Ritakumari, S.D.; Shibu, S.

    2007-01-01

    Seasonal variations in the phytoplankton density, diversity, gross production and related physicochemical parameters of Poonthura estuary have been followed for a period of one year. The polluted nature of the water body favored a higher density of phytoplankters, which exhibited a positive correlation with gross production. The influence of various physicochemical parameters, phytoplankton density and species diversity on gross production is discussed.

  14. Conhecimento, interdisciplinaridade e Psicologia Ambiental

    Directory of Open Access Journals (Sweden)

    Ombretta Romice

    2005-01-01

    Full Text Available Responde às questões - como os métodos da Psicologia Ambiental devem ser discutidos em um enquadramento interdisciplinar; a Psicologia Ambiental pede alguma abordagem metodológica especial; como a intervenção ambiental é determinada pela interdisciplinaridade; quais são estas disciplinas e como elas se relacionam entre si - baseando-se em experiências profissionais como orientador em um projeto com comunidade, com habitação popular e exclusão social em vários países da Europa, e como consultora. Conclui que as abordagens usadas pelas diferentes profissões são muito separadas, e que apenas metas comuns não são suficientes, sendo também necessários um treino conjunto e identidade de valores.

  15. Biogeochemical value of managed realignment, Humber estuary, UK

    International Nuclear Information System (INIS)

    We outline a plausible, albeit extreme, managed realignment scenario ('Extended Deep Green' scenario) for a large UK estuary to demonstrate the maximum possible biogeochemical effects and economic outcomes of estuarine management decisions. Our interdisciplinary approach aims to better inform the policy process, by combining biogeochemical and socioeconomic components of managed realignment schemes. Adding 7494 ha of new intertidal area to the UK Humber estuary through managed realignment leads to the annual accumulation of a 1.2 x 105 t of 'new' sediment and increases the current annual sink of organic C and N, and particle reactive P in the estuary by 150%, 83% and 50%, respectively. The increase in intertidal area should also increase denitrification. However, this positive outcome is offset by the negative effect of enhanced greenhouse gas emissions in new marshes in the low salinity region of the estuary. Short-term microbial reactions decrease the potential benefits of CO2 sequestration through gross organic carbon burial by at least 50%. Net carbon storage is thus most effective where oxidation and denitrification reactions are reduced. In the Humber this translates to wet, saline marshes at the seaward end of estuaries. Cost-benefit analysis (CBA) was used to determine the economic efficiency of the Extended Deep Green managed realignment. When compared to a 'Hold-the-Line' future scenario, i.e. the present state/extent of sea defences in the estuary, the CBA shows that managed realignment is cost effective when viewed on > 25 year timescales. This is because capital costs are incurred in the first years, whereas the benefits from habitat creation, carbon sequestration and reduced maintenance costs build up over time. Over 50- and 100-year timescales, the Extended Deep Green managed realignment scenario is superior in efficiency terms. The increased sediment accumulation is also likely to enhance storage of contaminant metals. In the case of Cu, a metal

  16. Fitorremediación, una tecnología que involucra a plantas y microorganismos en el saneamiento ambiental

    Directory of Open Access Journals (Sweden)

    Jeannette Marrero-Coto

    2012-01-01

    Full Text Available Uno de los rasgos distintivos de la sociedad moderna es la creciente generación de contaminantes ambientales, lo que trae consigo daños considerables a la salud humana y a la diversidad biológica. Los metales pesados son contaminantes que necesitan especial atención porque pueden permanecer varias décadas en el suelo y concentrarse en las cadenas tróficas. Las tecnologías desarrolladas para el saneamiento de ambientes contaminados con metales pesados son costosas y requieren un largo período de tiempo para su ejecución. La fitorremediación es una vertiente de la biorremediación que surge recientemente como alternativa ante esta problemática ambiental, y se basa en el uso de plantas que acumulan elevadas concentraciones de metales en sus tejidos para contener, remover o neutralizar contaminantes, mediante mecanismos de captura de metales propios de estas plantas y/o por los microorganismos que se desarrollan en la rizosfera. Estudios previos sugieren que los microorganismos rizosféricos poseen mecanismos capaces de alterar la circulación de metales en el medio ambiente, con efectos subsecuentes en el potencial de la planta para su captación en la raíz. En la actualidad, la fitorremediación no es una tecnología disponible comercialmente. Los progresos en el campo son limitados por falta de conocimiento de las interacciones complejas en la rizosfera y los mecanismos de plantas hiperacumuladoras que permiten la translocación del metal y su acumulación. Esta revisión responde a la necesidad de brindar mayores conocimientos que aumenten la rentabilidad y eficacia de estas plantas, debido a que su aplicación resulta muy importante en la protección del medio ambiente.

  17. Validating Firewalls in Mobile Ambients

    DEFF Research Database (Denmark)

    Nielson, Flemming; Nielson, Hanne Riis; Hansen, René Rydhof;

    1999-01-01

    The ambient calculus is a calculus of computation that allows active processes (mobile ambients) to move between sites. A firewall is said to be protective whenever it denies entry to attackers not possessing the required passwords. We devise a polynomial time algorithm for rejecting proposed...... firewalls that are not guaranteed to be protective. This is based on a control flow analysis for recording what processes may turn up inside what other processes; in particular, we develop a syntax-directed system for specifying the acceptability of an analysis, we prove that all acceptable analyses are...... semantically sound, and we demonstrate that each process admits a least analysis....

  18. Ambient cosmology and spacetime singularities

    CERN Document Server

    Antoniadis, Ignatios

    2015-01-01

    We present a new approach to the issues of spacetime singularities and cosmic censorship in general relativity. This is based on the idea that standard 4-dimensional spacetime is the conformal infinity of an ambient metric for the 5-dimensional Einstein equations with fluid sources. We then find that the existence of spacetime singularities in four dimensions is constrained by asymptotic properties of the ambient 5-metric, while the non-degeneracy of the latter crucially depends on cosmic censorship holding on the boundary.

  19. Ambient cosmology and spacetime singularities

    International Nuclear Information System (INIS)

    We present a new approach to the issues of spacetime singularities and cosmic censorship in general relativity. This is based on the idea that standard 4-dimensional spacetime is the conformal infinity of an ambient metric for the 5-dimensional Einstein equations with fluid sources. We then find that the existence of spacetime singularities in four dimensions is constrained by asymptotic properties of the ambient 5-metric, while the non-degeneracy of the latter crucially depends on cosmic censorship holding on the boundary. (orig.)

  20. Medio ambiente y responsabilidad social

    OpenAIRE

    Roa Buitrago, Rosa Isabel

    2012-01-01

    Las organizaciones, dentro de los procesos de responsabilidad social y con el fin de mejorar la calidad de vida de las comunidades que impactan, han optado por proteger y preservar el medio ambiente de acuerdo a ciertos protocolos y normas internacionales que generan una cultura al respecto. Este cuaderno de investigación aborda la norma ISO 26000, la cual asume el tema de la Responsabilidad Social Empresarial (RSE) en materia de medio ambiente y es una guía para ser implementada en las orga...

  1. Ambient cosmology and spacetime singularities

    Energy Technology Data Exchange (ETDEWEB)

    Antoniadis, Ignatios [Bern University, Albert Einstein Center for Fundamental Physics, Institute for Theoretical Physics, Bern (Switzerland); Ecole Polytechnique, Palaiseau (France); Cotsakis, Spiros [CERN, Theory Division, Department of Physics, Geneva 23 (Switzerland); National Technical University, School of Applied Mathematics and Physical Sciences, Athens (Greece)

    2015-01-01

    We present a new approach to the issues of spacetime singularities and cosmic censorship in general relativity. This is based on the idea that standard 4-dimensional spacetime is the conformal infinity of an ambient metric for the 5-dimensional Einstein equations with fluid sources. We then find that the existence of spacetime singularities in four dimensions is constrained by asymptotic properties of the ambient 5-metric, while the non-degeneracy of the latter crucially depends on cosmic censorship holding on the boundary. (orig.)

  2. Biogeochemistry of the Kem' River estuary, White Sea (Russia

    Directory of Open Access Journals (Sweden)

    V. R. Shevchenko

    2005-01-01

    Full Text Available The biogeochemistry of the river-sea interface was studied in the Kem' River (the largest river flowing to the White Sea from Karelian coast estuary and adjacent area of the White Sea onboard the RV 'Ekolog' in summer 2001, 2002 and 2003. The study area can be divided into 3 zones: I - the estuary itself, with water depth from 1 to 5m and low salinity in the surface layer (salinity is lower than 0.2psu in the Kem' River and varies from 15 to 20psu in outer part of this zone; II - the intermediate zone with depths from 5 to 10m and salinity at the surface from 16 to 22psu; III - the marine zone with depths from 10 to 29 m and salinity 21-24.5psu. Highest concentrations of the suspended particulate matter (SPM were registered in the Kem' mouth (5-7mg/l. They sharply decreased to values org to nitrogen (N ratio (Corg/N in both suspended matter and bottom sediments decreases from the river to the marine part of the mixing zone (from 8.5 to 6.1 in the suspended matter and from 14.6 to 7.5 in the bottom sediments, demonstrating that content of terrestrial-derived organic matter decreases and content of marine organic matter increases from the river mouth to the sea. The Kem' estuary exhibits a similar character of biogeochemial processes as in the large Arctic estuaries, but the scale of these processes (amount of river input of SPM, POC, area of estuaries is different.

  3. Columbia River Estuary Ecosystem Classification — Concept and application

    Science.gov (United States)

    Simenstad, Charles A.; Burke, Jennifer L.; O'Connor, Jim E.; Cannon, Charles; Heatwole, Danelle W.; Ramirez, Mary F.; Waite, Ian R.; Counihan, Timothy D.; Jones, Krista L.

    2011-01-01

    This document describes the concept, organization, and application of a hierarchical ecosystem classification that integrates saline and tidal freshwater reaches of estuaries in order to characterize the ecosystems of large flood plain rivers that are strongly influenced by riverine and estuarine hydrology. We illustrate the classification by applying it to the Columbia River estuary (Oregon-Washington, USA), a system that extends about 233 river kilometers (rkm) inland from the Pacific Ocean. More than three-quarters of this length is tidal freshwater. The Columbia River Estuary Ecosystem Classification ("Classification") is based on six hierarchical levels, progressing from the coarsest, regional scale to the finest, localized scale: (1) Ecosystem Province; (2) Ecoregion; (3) Hydrogeomorphic Reach; (4) Ecosystem Complex; (5) Geomorphic Catena; and (6) Primary Cover Class. We define and map Levels 1-3 for the entire Columbia River estuary with existing geospatial datasets, and provide examples of Levels 4-6 for one hydrogeomorphic reach. In particular, three levels of the Classification capture the scales and categories of ecosystem structure and processes that are most tractable to estuarine research, monitoring, and management. These three levels are the (1) eight hydrogeomorphic reaches that embody the formative geologic and tectonic processes that created the existing estuarine landscape and encompass the influence of the resulting physiography on interactions between fluvial and tidal hydrology and geomorphology across 230 kilometers (km) of estuary, (2) more than 15 ecosystem complexes composed of broad landforms created predominantly by geologic processes during the Holocene, and (3) more than 25 geomorphic catenae embedded within ecosystem complexes that represent distinct geomorphic landforms, structures, ecosystems, and habitats, and components of the estuarine landscape most likely to change over short time periods.

  4. Flux of 238U and 232Th in Changjiang estuary

    International Nuclear Information System (INIS)

    The study of fluxes of the U, Th of Changjiang River into the East China Sea and its adjacent waters is basic work to understanding of U, Th tracer theirselves and their corresponding biogeochemical cycles process in estuaries, coastal. By sampling in the Xuliujing (i.e. the interface between fresh water and sea water) every month, 200 L water was filtered through 0.45μm fabric cartridge to collect particle nuclides. The dissolved nuclides were co-precipitated using Fe(OH)3 and MnO2. The range of 238U activity in water is 2.30-10.32 Bq·m-3, with an average of 5.48±1.19 Bq·m-3; the activity of 232Th is 1.08-2.32 Bq·m-3, with an average of 1.75±0.29 Bq·m-3. Changjiang River conveyed 238U 4.06 x 1012Bq, 232Th 1.54 x 1012 Bq into the estuary every year. Further study of the seasonal variations 238U, 232Th input to the sea, indicating that: the activity of 238U and Changjiang River estuary water flux have a certain degree of negative correlation (R2=0.65, n=12); the main source of 232Th is the weathering of the river. The activity of 232Th is large on the spring and autumn because of strong weathering in Changjiang Basin comparison with other seasons. Compared with the other estuaries in the world, the flux of 238U and 232Th of the Changjiang River estuary is large because of its large fluxes of sediments and runoff in the world. (authors)

  5. Los estudios sobre el ambiente y la ciencia ambiental

    Directory of Open Access Journals (Sweden)

    Amelia Nancy Giannuzzo

    2010-03-01

    Full Text Available La existencia de la ciencia ambiental es reconocida en libros, revistas de publicación científica y carreras de grado y posgrado. Sin embargo, se desconoce su existencia en forma literal o indirecta, al no ser considerado su aporte, por ejemplo, en los planteos referidos sobre la ciencia y la tecnología de la sustentabilidad. En este trabajo se presentan estos antecedentes, relacionándolos con el objetivo del mismo, que es el de aportar a la dilucidación de la existencia y conformación de la ciencia ambiental. Para esto, se analiza la relación de las disciplinas con la dimensión compleja del ambiente como objeto de estudio y aspectos metodológicos derivados. A los fines de aportar al esclarecimiento conceptual, se identifican las distintas acepciones de ambiente comúnmente referidas en la bibliografía. Además, se discuten aspectos relacionados de multidisciplinariedad, interdisciplinariedad y transdisciplinariedad, y sobre el status epistémico de la ciencia ambiental. Se concluye que una mayor precisión conceptual embasada en un marco compartido por las disciplinas que estudian el ambiente, incluida la ciencia ambiental, y los distintos actores involucrados en las problemáticas ambientales, favorecerá el refinamiento de las metodologías tendientes a disminuir la fragmentación de las investigaciones concernientes y las aplicaciones para su resolución.The existence of an environmental science is recognized in books, journals of science as well as in undergraduate and graduate studies. Its existence, however, is unknown either literally or indirectly when, for instance, its contribution to topics connected to the science and technology of sustainability is not considered. This background is presented in this paper and connected to its objective, which is to elucidate the existence and structure of the environmental science. To this goal, I analyse the relationship of the disciplines with the complex dimension of the environment

  6. Feeding preferences of estuarine mysids Neomysis integer and Rhopalophthalmus tartessicus in a temperate estuary (Guadalquivir Estuary, SW Spain)

    Science.gov (United States)

    Vilas, César; Drake, Pilar; Fockedey, Nancy

    2008-04-01

    Mysid shrimps are an important component of estuarine food webs because they play a key role in energy transfer as intermediate prey. We investigated the seasonal, tidal and depth specific variation in the diet of the estuarine mysids Neomysis integer and Rhopalophthalmus tartessicus and explored its implications for the planktonic community structure of a temperate estuary (Guadalquivir Estuary, SW Spain). Neomysis integer is an opportunistic omnivore feeding mainly on mesozooplankton and on members of the detrital-microbial loop, shifting prey seasonally according to availability. In contrast, R. tartessicus showed a more carnivorous diet and shifted its target prey during seasons of low resource availability. Despite statistically significant differences in diet composition, both species shared prey of similar size, particularly juvenile Mesopodopsis slabberi, the most abundant mysid species in this estuary, and copepods. Although these similarities imply inter-specific resource competition, their co-existence is achieved by niche partitioning and spatial segregation: the higher osmoregulatory capacity and foraging plasticity of N. integer confers a broader niche breadth for this species allowing N. integer to inhabit the more stressful oligohaline region of the estuary where R. tartessicus cannot survive. We propose that this mechanism relaxes the potential for competition between N. integer and R. tartessicus.

  7. Circulation and suspended particulate matter transport in a tidally dominated estuary: caravelas estuary, Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    Carlos Augusto França Schettini

    2010-03-01

    Full Text Available The circulation and transport of suspended particulate matter in the Caravelas Estuary are assessed. Nearly-synoptic hourly hydrographic, current (ADCP velocity and volume transport and suspended particulate matter data were collected during a full semidiurnal spring tide, on the two transects Boca do Tomba and Barra Velha and on longitudinal sections at low and high tide. On the first transect the peak ebb currents (-1.5 ms-1 were almost twice as strong as those of the wider and shallow Barra Velha inlet (-0.80 ms-1 and the peak flood currents were 0.75 and 0.60 ms-1, respectively. Due to the strong tidal currents both inlets had weak vertical salinity stratification and were classified with the Stratification-circulation Diagram as Type 2a (partially mixed-weakly stratified and Type 1a (well mixed. Volume transports were very close, ranging from -3,500 to 3,100 m³s-1 at the ebb and flood, respectively, with a residual -630 m³s-1. The concentration of the suspended particulate matter was closely related to the tidal variation and decreased landwards from 50 mg.L-1 at the estuary mouth, to 10 mg.L-1 at distances of 9 and 16 km for the low and high tide experiments, respectively. The total residual SPM transport was out of the estuary at rates of -18 tons per tidal cycle.A circulação e o transporte de material particulado em suspensão no Estuário de Caravelas são pesquisados. Dados quase-sinóticos hidrográficos, de correntes (velocidade e transporte de volume com ADCP e de material particulado em suspensão, foram medidos em intervalos horários durante um ciclo semidiurno de maré de sizígia, em duas seções transversais na Boca do Tomba e na Barra Velha e também em seções longitudinais na baixa-mar e na preamar. Na primeira transversal as correntes máximas de vazante (-1,50 m s-1 foram quase duas vezes mais intensas do que na seção transversal mais larga e rasa Barra Velha, (-0,80 m s-1 e as maiores velocidades das correntes de

  8. Shape analysis for Mobile Ambients

    DEFF Research Database (Denmark)

    Nielson, Hanne Riis; Nielson, Flemming

    The ambient calculus is a calculus of computation that allows active processes to move between sites. We present an analysis inspired by state-of-the-art pointer analyses that safety and accurately predicts which processes may turn up at what sites during the execution of a composite system. The...

  9. Abstract Interpretation of Mobile Ambients

    DEFF Research Database (Denmark)

    Hansen, René Rydhof; Jensen, J. G.; Nielson, Flemming; Nielson, Hanne Riis

    We demonstrate that abstract interpretation is useful for analysing calculi of computation such as the ambient calculus (which is based on the p-calculus); more importantly, we show that the entire development can be expressed in a constraint-based formalism that is becoming exceedingly popular for...

  10. Shape analysis for mobile ambients

    DEFF Research Database (Denmark)

    Nielson, Hanne Riis; Nielson, Flemming

    2001-01-01

    The ambient calculus is a calculus of computation that allows active processes to move between sites. We present an analysis inspired by state-of-the-art pointer analyses that safely and accurately predicts which processes may turn up at what sites during the execution of a composite system. The...

  11. TERCEIRO SETOR E MEIO AMBIENTE

    OpenAIRE

    Melo, Marina Félix de

    2012-01-01

    Objetivamos discutir, brevemente, como têm se dado as discussões sobre o Terceiro Setor brasileiro e, particularmente, sobre as ONGs que atuam em defesa do meio ambiente, levantando questionamentos acerca das limitações enfrentadas pelo Terceiro Setor neste contexto

  12. Shape analysis for Mobile Ambients

    DEFF Research Database (Denmark)

    Nielson, Hanne Riis; Nielson, Flemming

    2000-01-01

    The ambient calculus is a calculus of computation that allows active processes to move between sites. We present an analysis inspired by state-of-the-art pointer analyses that safety and accurately predicts which processes may turn up at what sites during the execution of a composite system. The ...

  13. Measuring the contribution of benthic ecosystem engineering species to the ecosystem services of an estuary: A case study of burrowing shrimps in Yaquina Estuary, Oregon - April 2009

    Science.gov (United States)

    Burrowing shrimps are regarded as ecosystem engineering species in many coastal ecosystems worldwide, including numerous estuaries of the west coast of North America (Baja California to British Columbia). In estuaries of the U.S. Pacific Northwest, two species of large burrowing...

  14. Measuring the contribution of benthic ecosystem engineering species to the ecosystem services of an estuary: A case study of burrowing shrimps in Yaquina Estuary, Oregon

    Science.gov (United States)

    Burrowing shrimps are regarded as ecosystem engineering species in many coastal ecosystems worldwide, including numerous estuaries of the west coast of North America (Baja California to British Columbia). In estuaries of the U.S. Pacific Northwest, two species of large burrowing...

  15. Estuary Data Mapper: A Stand-Alone Tool for Geospatial Data Access, Visualization and Download for Estuaries and Coastal Watersheds of the United States

    Science.gov (United States)

    The US EPA Estuary Data Mapper (EDM; http://badger.epa.gov/rsig/edm/index.html) has been designed as a free stand-alone tool for geospatial data discovery, visualization, and data download for estuaries and their associated watersheds in the conterminous United States. EDM requi...

  16. Estuary Data Mapper: A Stand-Alone Tool for Geospatial Data Access, Visualization and Download for Estuaries and Coastal Watersheds of the United States. (UNH)

    Science.gov (United States)

    The US EPA Estuary Data Mapper (EDM; http://badger.epa.gov/rsig/edm/index.html) has been designed as a free stand-alone tool for geospatial data discovery, visualization, and data download for estuaries and their associated watersheds in the conterminous United States. EDM requi...

  17. Why Do Some Estuaries Close: A Model of Estuary Entrance Morphodynamics.

    Science.gov (United States)

    McSweeney, S. L.; Kennedy, D. M.; Rutherfurd, I.

    2014-12-01

    Intermittently Closed/Open Coastal Lakes/Lagoons (ICOLLs) are a form of wave-dominated, microtidal estuary that experience periodic closure in times of low river flow. ICOLL entrance morphodynamics are complex due to the interaction between wave, tidal and fluvial processes. Managers invest substantial funds to artificially open ICOLLs as they flood surrounding property and infrastructure, and have poor water quality. Existing studies examine broad scale processes but do not identify the main drivers of entrance condition. In this research, the changes in entrance geomorphology were surveyed before and after artificial entrance openings in three ICOLLs in Victoria, Australia. Changes in morphology were related to continuous measures of sediment volume, water level, tide and wave energy. A six-stage quantitative phase model of entrance geomorphology and hydrodynamics is presented to illustrate the spatio-temporal variability in ICOLL entrance morphodynamics. Phases include: breakout; channel expansion with rapid outflow; open with tidal exchange; initial berm rebuilding with tidal attenuation; partial berm recovery with rising water levels; closed with perched water levels. Entrance breakout initiates incision of a pilot channel to the ocean, whereby basin water levels then decline and channel expansion as the headcut migrates landwards. Peak outflow velocities of 5 m/s-3 were recorded and channel dimensions increased over 6 hrs to 3.5 m deep and 140 m wide. When tidal, a clear semi-diurnal signal is superimposed upon an otherwise stable water level. Deep-water wave energy was transferred 1.8 km upstream of the rivermouth with bores present in the basin. Berm rebuilding occurred by littoral drift and cross-shore transport once outflow ceased and microscale bedform features, particularly antidunes, contributed to sediment progradation. Phase duration is dependant on how high the estuary was perched above mean sea level, tidal prism extent, and onshore sediment supply

  18. Research, Monitoring, and Evaluation for the Federal Columbia River Estuary Program.

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Gary E.; Diefenderfer, Heida L. (Pacific Northwest National Laboratory)

    2008-02-20

    The purpose of this document is to describe research, monitoring, and evaluation (RME) for the Federal Columbia River Estuary Program, hereafter called 'the Estuary Program'. The intent of this RME effort is to provide data and information to evaluate progress toward meeting program goals and objectives and support decision making in the Estuary Program. The goal of the Estuary Program is to understand, conserve, and restore the estuary ecosystem to improve the performance of listed salmonid populations. The Estuary Program has five general objectives, designed to fulfill the program goal, as follows: (1) Understand the primary stressors affecting ecosystem controlling factors, such as ocean conditions and invasive species. (2) Conserve and restore factors controlling ecosystem structures and processes, such as hydrodynamics and water quality. (3) Increase the quantity and quality of ecosystem structures, i.e., habitats, juvenile salmonids use during migration through the estuary. (4) Maintain the food web to benefit salmonid performance. (5) Improve salmonid performance in terms of life history diversity, foraging success, growth, and survival. The goal of estuary RME is to provide pertinent and timely research and monitoring information to planners, implementers, and managers of the Estuary Program. The goal leads to three primary management questions pertaining to the main focus of the Estuary Program: estuary habitat conservation and restoration. (1) Are the estuary habitat actions achieving the expected biological and environmental performance targets? (2) Are the offsite habitat actions in the estuary improving juvenile salmonid performance and which actions are most effective at addressing the limiting factors preventing achievement of habitat, fish, or wildlife performance objectives? (3) What are the limiting factors or threats in the estuary/ocean preventing the achievement of desired habitat or fish performance objectives? Performance measures

  19. The variations of suspended sediment concentration in Yangtze River Estuary

    Institute of Scientific and Technical Information of China (English)

    杨云平; 张明进; 李义天; 张为

    2015-01-01

    With the Yangtze River Estuary as an example, this paper analyzes the influence of human activity on the sea water content, the sediment content and the regional transport situation. In both flood seasons and dry seasons, as well as in the whole year, the sediment discharge rate and the suspended sediment concentration (SSC) in the estuary area of the Yangtze River show decreasing trends. In the estuary area, the amount of sediment transported into the South and North Branches and the offshore area is also in a decreasing trend over the years. The SSCs at the sections at the entrances of the South Branch, the South Channel, the North Channel and the South Passage in the Yangtze River Estuary show decreasing trends during 1959-2011. The remote-sensing data reveal that for the same runoff and tidal current combination, the SSC in the surface water is decreased, caused by the dramatic decrease in the sediment discharge and the sediment content from the watershed. Although the SSC in the offshore area does not exhibit an apparent decreasing trend, the SSC in the nearshore area drops by 21.42% during the period of 2003-2011 as compared with that during the period of 1985-2002 before the impounding of the Three Gorges Reservoir. The sediment re-suspension in the estuary slows down the reduction of the SSC. The period of 2003-2011 is dry years for the Yangtze River, when the flow is relatively low. The peak value of the SSC in the coast area shifts inwards for about 1/6°degree of longitude. Due to the deepwater channel improvement project in the North Passage at the Yangtze River Estuary in 1998, the SSC in the waterway area is decreased. With the decrease of the divided flow ratio and the sediment splitting ratio in the entrance and the exit of the North Passage, the SSC in the upper and lower reaches of the North Passage during the period of 2008-2011 is decreased by about 14.25% as compared with that during the period of 2000-2007. Primarily due to the jetty at the

  20. Plastic pollution in five urban estuaries of KwaZulu-Natal, South Africa.

    Science.gov (United States)

    Naidoo, Trishan; Glassom, David; Smit, Albertus J

    2015-12-15

    Monitoring plastic concentrations in estuaries is vital in assessing the magnitude of terrestrial inputs to oceanic environments. Data on plastics ≤ 5 mm in estuaries are scant. This study determined microplastic levels within five estuaries along the Durban coastline and on intervening beaches. Plastics were isolated from estuarine sediment, beach sediment and the surface water of each estuary and characterised. Sediment at the Bayhead area of Durban harbour had the highest average plastic concentrations (745.4 ± 129.7 particles per 500 ml) and an attenuating concentration trend away from the city centre was found. Prevailing south to north longshore drift was hypothesised to result in plastic accumulation on the northern shores of beaches with estuarine effluents, however, this was not found. Fragments composed the largest percent of plastics (59%) found in Bayhead, whereas fibres dominated other estuaries with proportions ranging from 38% of total plastics in the uMgeni estuary to 66% in the Mdloti. PMID:26476863

  1. Estuary response to an abrupt, large increase in groundwater nitrate input

    International Nuclear Information System (INIS)

    Long term measurements of NO3- concentrations in two estuaries on Buzzards Bay, Massachusetts, USA, coupled with a large, step-wise increase in the groundwater NO3- to one of those estuaries, have allowed the effects on the estuary to be isolated and quantified. The results show that prior to the abrupt increase, the estuary responded in a linear manner to NO3- input, as suggested in the literature. After the abrupt increase, the estuary initially absorbed the greatly increased groundwater input, and after a year the response became a fluctuating variable with periods of less than 1 year. It is proposed that this indicates increased recycling from the sediments. This behavior is consistent with models of nutrient-induced regime shift in its early stages, as described in the literature. Future isotopic analysis is suggested as a means to confirm the estuary mechanism.

  2. Pollutant Flux Estimation in an Estuary Comparison between Model and Field Measurements

    OpenAIRE

    Yen-Chang Chen; Wu-Seng Lung; Han-Chung Yang; Bo-Jhih Chen; Chien-Hung Chen

    2014-01-01

    This study proposes a framework for estimating pollutant flux in an estuary. An efficient method is applied to estimate the flux of pollutants in an estuary. A gauging station network in the Danshui River estuary is established to measure the data of water quality and discharge based on the efficient method. A boat mounted with an acoustic Doppler profiler (ADP) traverses the river along a preselected path that is normal to the streamflow to measure the velocities, water depths and water qua...

  3. ENDIS-RISKS: endocrine disruption in the Scheldt estuary - a field study

    OpenAIRE

    Rappé, K.; Ghekiere, A; Noppe, H; Monteyne, E.; Fockedey, N.; Janssen, C.; De Brabander, H.; Roose, P.; Vincx, M.

    2007-01-01

    ENDIS-RISKS, a multidisciplinary research project with five institutes, evaluates the distribution, exposure and effects of endocrine disruptors in the Scheldt Estuary. This estuary is known to be one of the most polluted estuaries in the world. Untreated domestic wastewater and effluents of the industrial areas of Ghent and Antwerp are to a large extent responsible for this pollution. During an intensive field study of four years, eight sampling campaigns were executed on seven sampling poin...

  4. The meiofauna distribution in correlation with environmental characteristics in 5 Mekong estuaries, Vietnam

    OpenAIRE

    Ngo, X.Q.; Smol, N.; Vanreusel, A.

    2013-01-01

    Meiofauna assemblages in 5 estuaries of the Mekong river system (Cua Tieu, Cua Dai, Ba Lai, Co Chien and Dinh An) were sampled for community analysis in March 2009, the dry season. The objectives of this research were to provide the first base line survey of meiofauna assemblages in the 5 Mekong estuaries, and to understand how environmental characteristics affect the densities, diversity and structure of the meiofauna. In each estuary, three to four sampling stations were chosen along the sa...

  5. Morphodynamics of a gravel-dominated macrotidal estuary: Rio Grande, Tierra del Fuego

    OpenAIRE

    Federico I. Isla; Gustavo G. Bujalesky

    2004-01-01

    Rio Grande city (Tierra del Fuego) is located on two attached beach systems, one of Upper Pleistocene (Sangamonian) and the other of Holocene age. Both gravel spits grew from north to south modifying the inlet of the Rio Grande estuary. The present estuary is constrained by the modern and recurved spit Popper Spit. The main characteristic of this macrotidal estuary is that both margins and the bottom are mainly composed of rounded gravel. Expansion of the city is limited by oceanic and estuar...

  6. Migration dynamics of clupeoids in the Schelde estuary: a stable isotope approach

    DEFF Research Database (Denmark)

    Guelinckx, J.; Maes, J.; De Brabandere, Loreto;

    2006-01-01

    movement in the Schelde estuary. Seasonal movements of clupeoids in the Schelde estuary were analyzed by separating the temporal abundance patterns into migration groups based on their muscle isotopic composition. Immigration and emigration seem to occur continuously throughout the year. Most exchange...... occurred in November. During winter, immigration remained high but gradually decreased. Although the herring and sprat abundance further declined in the estuary during February and March, large seaward emigration was not fully demonstrated. As temporal overlap between immigration and emigration is...

  7. Persistence and Non-target Impact of Imazapyr Associated with Smooth Cordgrass Control in an Estuary

    OpenAIRE

    Patten, Kim

    2003-01-01

    The herbicide (±-2-[4,5-dihydro-4-methyl-4-(1-methylethyl)- 5-oxo-1 H -imidazol-2-yl]-3-pyridinecarboxylic acid (imazapyr) has shown potential to control smooth cordgrass (Spartina alterniflora Loisel), a noxious weed in many estuaries throughout the world. Research was conducted under tidal estuary conditions in Willapa Bay, Washington, to determine imazapyr’s persistence and aquatic risk and impact to non-target estuary species. Persistence of imazapyr in water...

  8. The contribution of scientific research for integrated coastal management: the Mondego estuary as study case

    OpenAIRE

    Costa, Sonia; Azeiteiro, Ulisses; Pardal, Miguel

    2013-01-01

    The present paper quantifies and summarizes the research performed in the Mondego estuary (Portugal) over the last decades. Online databases were used to quantitatively assess the international publications, the master dissertations and PhD theses focused in the research about that estuary, from 1989 to 2012. In general, there had been a notable growth trend in publication output. Estuarine, Coastal and Shelf Science was the most active journal publishing on Mondego estuary. Field studies wer...

  9. Response of Nereis diversicolor population (Polychaeta, Nereididae) to the pollution impact - Authie and Seine estuaries (France)

    Science.gov (United States)

    Gillet, P.; Mouloud, M.; Durou, C.; Deutsch, B.

    2008-01-01

    A survey within the French National Programme of Ecotoxicology was carried out in 2002, 2003 and 2004 to study the response of Nereis diversicolor populations (Polychaeta, Nereididae) to the impact of pollution in the Authie estuary (non-contaminated site) and in the Seine estuary (contaminated site). In the period studied, the density varied from 672 ind. m -2 to 3584 ind. m -2 in the Authie estuary and from 80 ind. m -2 to 920 ind. m -2 in the Seine estuary. Biomass varied from 3.94 g m -2 (dry weight) in February 2004 to 38.0 g m -2 in August 2003 in the Authie estuary and from 3.4 g m -2 in February 2002 to 0.6 g m -2 in February 2004 in the Seine estuary. Density and biomass of the populations of N. diversicolor were consistently lower in the Seine estuary than in the Authie estuary. Size frequency histograms permit the analysis of the cohorts as well as the elaboration of the growth curves. For the individuals from the Authie estuary, the relation between dry weight (DW) and length L3 (prostomium, peristomium and chaetiger 1) was DW = 4.2205 L3 2.9832. For those from the Seine estuary, the relation between dry weight and L3 was DW = 0.4697e 1.7209L3. The individuals of N. diversicolor should belong to eight cohorts in Authie estuary (two cohorts each year) instead of six cohorts for those from the Seine estuary. These differences can be attributed to the effect of pollution on the population of N. diversicolor.

  10. Rasgos de historia de vida de especies en una comunidad vegetal alterada principalmente por pastoreo en un páramo húmedo (Parque Nacional Natural Chingaza, Colombia

    Directory of Open Access Journals (Sweden)

    Vargas Ríos Jesús Orlando

    2007-04-01

    Full Text Available Se estudiaron once rasgos de historia de vida (morfológicos y de regeneración de plantas vasculares, en
    cuatro sitios con diferente grado de alteración, que hacen parte de una misma unidad de paisaje y condiciones
    topográficas similares. Ubicados en los valles de los ríos Tunjo y Piedras Gordas, páramo de Palacio, parque nacional natural Chingaza, Cundinamarca, Colombia. Entre 3.400-3.600 m de altitud, a los 4º45’03’’N, 73º50’50’’W. Estos valles, principalmente el valle del río Tunjo tienen una larga historia de disturbio por quema y pastoreo de ganado vacuno. La comunidad natural es de Espeletia killipii, Chusquea tessellata y Calamagrostis effusa. Mediante un análisis de clasificación y un procedimiento de componentes principales (ACP se agruparon las especies de acuerdo a rasgos similares y se analizó su abundancia de acuerdo con el grado de alteración. Se identificaron tres grupos de especies, diferenciados principalmente por los rasgos morfológicos: tipo de planta, forma de crecimiento, hábito y altura. El grupo uno se caracteriza principalmente por especies graminoides (73%, erectas (100% en macolla (68% con alturas mayores a 5 cm (60%; el grupo dos por hierbas rastreras o postradas (76 % que forman cojines o tapetes (86% con alturas menores a 5 cm (79% y el grupo tres por hierbas (88% en roseta (100% que no forman cojines o tapetes. Cada uno de estos grupos, presentaron una máxima abundancia-cobertura a un grado de alteración en particular; el grupo uno, no es favorecido en su abundancia-cobertura al aumentar el grado de
    alteración, presenta su mayor abundancia en los sitios con alteración leve y sin alteración (33 y 30%; el grupo dos es característico del sitio con alteración alta, donde presento la mayor abundancia (44% y el grupo tres presentó su menor abundancia en el sitio con mayor grado de alteración (8%.

  11. Historical Ambient Air Quality Data Inventory

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Historical Ambient Air Quality Data Inventory contains measured and estimated data on ambient air pollution for use in assessing air quality, assisting in...

  12. Thermal impact assessment of multi power plant operations on estuaries

    International Nuclear Information System (INIS)

    The assessment of the thermal impact of multi power plant operations on large estuaries requires careful consideration of the problems associated with: re-entrainment, re-circulation, thermal interaction, delay in the attainment of thermal equilibrium state, and uncertainty in specifying open boundaries and open boundary conditions of the regions, which are critically important in the analysis of the thermal conditions in receiving water bodies with tidal dominated, periodically reversing flow conditions. The results of an extensive study in the Hudson River at Indian Point, 42 miles upstream of the ocean end at the Battery, concluded that the tidal-transient, multi-dimensional discrete-element (UTA) thermal transport models (ESTONE, FLOTWO, TMPTWO computer codes) and the near-field far-field zone-matching methodology can be employed with a high degree of reliability in the assessment of the thermal impact of multi power plant operations on tidal dominated estuaries

  13. Multibiomarker assessment of three Brazilian estuaries using oysters as bioindicators

    International Nuclear Information System (INIS)

    Oysters have been largely employed as bioindicators of environmental quality in biomonitoring studies. Crassostrea rhizophorae was selected to evaluate the health status of three estuarine areas impacted by anthropogenic activities along the Brazilian coast, in three estuarine complexes, ranging in latitude from 7 to 25 deg. S. In each estuary three sites were sampled in Winter and in Summer: a site considered as reference, and two sites next to contamination sources. Condition index was similar at all sites and estuaries, with the highest values found for Itamaraca oysters in Summer. Necrosis, hyperplasia, mucocyte hypertrophy and fusion of ordinary filaments were the main histopathological lesions observed. Muscle cholinesterase activity was overall similar, but with a strong seasonal effect. Inhibition or activation of branchial total ATPase and Na,K-ATPase activities at the contaminated sites was observed. The health status of these estuarine areas is quite similar, and the combined use of biomarkers is recommended

  14. Modeling centuries of estuarine morphodynamics in the Western Scheldt estuary

    Science.gov (United States)

    Dam, G.; Wegen, M.; Labeur, R. J.; Roelvink, D.

    2016-04-01

    We hindcast a 110 year period (1860-1970) of morphodynamic behavior of the Western Scheldt estuary by means of a 2-D, high-resolution, process-based model and compare results to a historically unique bathymetric data set. Initially, the model skill decreases for a few decades. Against common perception, the model skill increases after that to become excellent after 110 years. We attribute this to the self-organization of the morphological system which is reproduced correctly by the numerical model. On time scales exceeding decades, the interaction between the major tidal forcing and the confinement of the estuary overrules other uncertainties. Both measured and modeled bathymetries reflect a trend of decreasing energy dissipation, less morphodynamic activity, and thus a more stable morphology over time, albeit that the estuarine adaptation time is long (approximately centuries). Process-based models applied in confined environments and under constant forcing conditions may perform well especially on long (greater than decades) time scales.

  15. STUDY OF RED TIDE PREDICTION MODEL FOR THE CHANGJIANG ESTUARY

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    This paper based on field data (on red tide water quality monitoring at the Changjiang River mouth and Hutoudu mariculture area in Zhejiang Province from May to August in 1995, and May to September in 1996) presents an effective model for short term prediction of red tide in the Changjiang Estuary. The measured parameters include: depth, temperature, color diaphaneity, density, DO, COD and nutrients (PO4-P, NO2-N, NO3-N, NH4-N). The model was checked by field-test data, and compared with other related models.The model: Z=SAL-3.95 DO-2.974 PH-5.421 PO4-P is suitable for application to the Shengsi aquiculture area near the Changjiang Estuary.

  16. Structural lubricity under ambient conditions

    Science.gov (United States)

    Cihan, Ebru; İpek, Semran; Durgun, Engin; Baykara, Mehmet Z.

    2016-01-01

    Despite its fundamental importance, physical mechanisms that govern friction are poorly understood. While a state of ultra-low friction, termed structural lubricity, is expected for any clean, atomically flat interface consisting of two different materials with incommensurate structures, some associated predictions could only be quantitatively confirmed under ultra-high vacuum (UHV) conditions so far. Here, we report structurally lubric sliding under ambient conditions at mesoscopic (∼4,000–130,000 nm2) interfaces formed by gold islands on graphite. Ab initio calculations reveal that the gold–graphite interface is expected to remain largely free from contaminant molecules, leading to structurally lubric sliding. The experiments reported here demonstrate the potential for practical lubrication schemes for micro- and nano-electromechanical systems, which would mainly rely on an atomic-scale structural mismatch between the slider and substrate components, via the utilization of material systems featuring clean, atomically flat interfaces under ambient conditions. PMID:27350035

  17. Fiscalidad ambiental (curso 2011-2012)

    OpenAIRE

    Gil Maciá, Lorenzo

    2012-01-01

    Tema fiscalidad ambiental. 1. Necesidad económica y jurídica de la protección del medio ambiente. 2. Características, naturaleza y clasificación de los tributos ambientales. 3. Competencias tributarias en el ámbito estatal, autonómico y local. 4. La fiscalidad ambiental en la legislación fiscal española. 5. Perspectivas de futuro en materia de imposición ambiental.

  18. Estimation of dissolved inorganic nutrients fluxes from the Changjiang River into estuary

    Institute of Scientific and Technical Information of China (English)

    刘新成; 沈焕庭

    2001-01-01

    Because the estuary acts as either a trap or a source or both for nutrient elements and will modify greatly the riverine transport to the ocean, it is necessary to calculate the flux from river into estuary and that from estuary into sea, respectively. The present work aims to use a long-term record of nutrients concentrations and runoff discharges on H.e Datong section (625 km inland from the Changjiang River mouth) to identify the variability of nutrients concentrations and to estimate nutrients fluxes from the Changjiang River into the estuary.

  19. Macrobenthic Community in the Xiaoqing River Estuary in Laizhou Bay, China

    Institute of Scientific and Technical Information of China (English)

    LUO Xianxiang; ZHANG Shanshan; YANG Jianqiang; PAN Jinfen; TIAN Lin; ZHANG Longjun

    2013-01-01

    The macrobenthic community of the Xiaoqing River Estuary and the adjacent sea waters was investigated in May and November 2008,August 2009,and May and September 2010,respectively.A total of 95 species of macrobenthos were identified in the five cruises and most of them were polychaetes (46.39%),mollusks (28.86%) and crustaceans (20.62%).The Shannon-Wiener index of macrobenthos was lower than 2 in 67% sites.Along the stream channel,estuary and the coastal waters,the species of polychaetes reduced gradually,while the abundance increased at first and then decreased.The abundance was the biggest at regions with salinity of 5-20 in the estuary.The species and abundance of mollusks and crustaceans increased gradually.As for seasonal distribution,the species,abundance and biomass were higher in spring and lower in summer and autumn.Contemporaneously compared with Laizhou Bay and Yellow River Estuary,the species of macrobenthos appeared in the Xiaoqing River Estuary were much less,while the percentage of polychaetes was higher.Abundance and biomass were higher in Xiaoqing River estuary,then consequently followed by Laizhou Bay and Yellow River Estuary.The dominant species in Xiaoqing River Estuary was polychaete,and Layzhou Bay mollusk.The community structure characteristics of macrobenthos in the Xiaoqing River Estuary revealed a significant pollution status in this region.

  20. [Ambient assisted living - an overview].

    Science.gov (United States)

    Christiansen, St; Klötzer, J-P

    2015-09-01

    Ambient assisted living (AAL) technologies are mainly developed to support elderly people in their own homes and facilitate a longer, self-determined life. In addition to providing a demographic prognosis for Germany, the present publication includes the definition, classification and current market situation of AAL. Lastly, the benefit of AAL technologies to the insurance industry and the subsequent steps to be taken are addressed. PMID:26548006

  1. Crumpling under an ambient pressure

    OpenAIRE

    Lin, Y C; Wang, Y. L.; Liu, Y; Hong, T.M.

    2008-01-01

    A pressure chamber is designed to study the crumpling process under an ambient force. The compression force and its resulting radius for the ball obey a power law with an exponent that is independent of the thickness and initial size of the sheet. However, the exponent is found to be material-dependent and less than the universal value, 0.25, claimed by the previous simulations. The power law behavior disappears at high pressure when the compressibility drops discontinuously, which is suggest...

  2. Hypermedia in the Ambient Wood

    OpenAIRE

    Weal, Mark J; Michaelides, Danius T.; Thompson, Mark K.; De Roure, David C

    2003-01-01

    The Ambient Wood project, carried out as part of the Equator IRC, set out to provide an augmented learning experience for children in an outdoor environment. Using a variety of devices, the children gathered information about the woodland habitats performing basic scientific enquiry and hypothesis testing. In this paper we describe the supporting information infrastructure used in the project, focusing on how hypermedia tools and techniques were used to structure and deliver the information t...

  3. Environmental restoration of the Guadiaro river estuary, Cadiz (Spain)

    OpenAIRE

    2000-01-01

    During 1998, the Spanish Ministry of Environmental Protection has developed the restoration of the Guadiaro estuary, near the Strait of Gibraltar, through the Coastal General Directorate. The main environmental problems, amongst others, detected at the area were a high eutrophication level of the estuarine waters and fish mortality mainly due to the low summer river effluent, the urban sewage inputs and no tidal renovation caused by the blockage of the sand bar at the mouth...

  4. Nutrients, hypoxia and mass fishkill events in Tapi estuary, India.

    Digital Repository Service at National Institute of Oceanography (India)

    Ram, A.; JiyalalRam, M.J.; Rokade, M.A.; Bharti, S.; Vishwasrao, C.; Majithiya, D.

    and ultimately dead zones in the estuary. Fish mortality caused by natural and anthropogenic hypoxia has been reported in several coastal and estuarine waters and bays since 1900 (Diaz and Rosenberg 2008; Broszeit et al., 2013). Depending on the fish species..., or approximately 30% saturation) is emerging as a major threat to coastal ecosystems globally. More than 600 coastal and estuarine sites globally have developed hypoxia (Nixon, 2009; Diaz et al., 2010; Conley et al., 2011) which is an increase of approximately 5...

  5. Lateral variability of sediment transport in the Delaware Estuary

    Science.gov (United States)

    McSweeney, Jacqueline M.; Chant, Robert J.; Sommerfield, Christopher K.

    2016-01-01

    Lateral processes contribute significantly to circulation and material transport in estuaries. The mechanisms controlling transport may vary spatially such that shallow and deep regions of an estuary contribute differently to the total transport. An observational study was conducted to explore the importance of lateral variability in sediment transport mechanisms in the Delaware Estuary. Seven moorings were deployed across the channel in the region of the estuarine turbidity maximum (ETM) zone from April to August 2011. Time series of along-channel sediment transport reveal a consistent pattern of sediment export across the entire estuary during periods of high river discharge, followed by a transition to import within the channel and export on the flanks during low river flow. There is a persistent divergence of across-channel sediment fluxes on the Delaware side, where sediment from the flank is transported toward both the channel and wetland coast. Decomposition of the fluxes highlight that across-channel sediment transport is driven by mean lateral circulation, whereas along-channel transport is driven primarily by mean advection, with tidal pumping contributing to about 30% of total transport. The spatial and temporal variability of mean advection and tidal pumping were generally complementary, with both contributing to the observed sediment transport pathways. Tidal pumping, linked to tidal asymmetries in stratification and sediment resuspension, was shown to drive both ebb-driven export and flood-driven import depending on the tidal variability of stratification. The spatiotemporal patterns of sediment transport highlight the three-dimensional structure of the ETM and shed light on the variability of sediment transport mechanisms.

  6. Possible estuary-associated syndrome: symptoms, vision, and treatment.

    OpenAIRE

    Shoemaker, R C; Hudnell, H.K.

    2001-01-01

    The human illness designated as possible estuarine-associated syndrome (PEAS) by the Centers for Disease Control and Prevention (CDC) has been associated with exposure to estuaries inhabited by toxin-forming dinoflagellates, including members of the fish-killing toxic Pfiesteria complex (TPC), Pfiesteria piscicida and Pfiesteria shumwayae. Humans may be exposed through direct contact with estuarine water or by inhalation of aerosolized or volatilized toxin(s). The five cases reported here dem...

  7. 5.04 - Carbon Dioxide and Methane Dynamics in Estuaries

    OpenAIRE

    Borges, Alberto; Abril, Gwenaël

    2011-01-01

    Estuaries profoundly transform the large amounts of carbon delivered from rivers before their transfer to the adjacent coastal zone. As a consequence of the complex biogeochemical reworking of allochthonous carbon in the sediments and the water column, CO2 and CH4 are emitted into the atmosphere. We attempt to synthesize available knowledge on biogeochemical cycling of CO2 and CH4 in estuarine environments, with a particular emphasis on the exchange with the atmosphere. Unlike CH4, the global...

  8. Hidrodynamics influence assessment on Mondego Estuary eutrophication process

    OpenAIRE

    Duarte, António A. L. Sampaio; Pinho, José L. S.; Pardal, Miguel A. C.; Neto, João M.; Vieira, J. M. Pereira; Santos, Fernando S.

    2002-01-01

    The south arm of Mondego estuary is stressing by an eutrophication process due to massive nutrient loading from urbanised areas and diffusive runoff from intensively agricultural areas. A sampling program was carried out at three benthic sample points and at three other sites (river Pranto sluice, Armazéns channel mouth and Gala bridge) for water column monitoring. Available field data analysis allows concluding that the occurrence of green macroalgal blooms is strongly dependent on the hydro...

  9. Hydrographic and chemical observations in the Sierra Leone River estuary

    International Nuclear Information System (INIS)

    Hydrographic and chemical observations in the Sierra Leone River estuary are reported, a West-African river in the tropics. Because of the typical change between rainy season in the sommer months and dry season in winter time the research work has been adapted to these semi-annual changes. The collected data and results are given and discussed under this aspect of the seasonal fluctuations. (orig.)

  10. Time-dependent stratification in the Gauthami-Godavari Estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, T.V.N.

    character from highly stratified to vertically mixed types (Bowden 1977; Hass 1977; Nunes Vaz and Lennon 1987; Nu- nes Vaz 1990; Simpson et al. 1990; Nunes Vaz and Simpson 1994; Sharples et al. 1994). Because of anomalous tidal characteristics, the Gauthami...-Godavari estuary provides opportunities to examine the development of estuarine stratifi- cation and the accompanying dynamics. Increased exchange between surface and bottom water re- sults in an increase in the potential energy of the system and the generation...

  11. Water quality modelling of the western Scheldt estuary

    OpenAIRE

    Ouboter, M.R.L.; Van Eck, B.T.M.; Van Gils, J.A.G.; Sweerts, J.P.; Villars, M.T.

    1998-01-01

    1n 1987 the National Institute for Coastal and Marine Management (the Netherlands) initiated the SAWES project (Systems Analysis WEstern Scheldt). The main goals of the project were to acquire knowledge with respect to the pollution problems in the Scheldt estuary and to apply this knowledge to management issues of the Scheldt on an operational level. The main interest was to understand quantitatively the relation between inputs of polluting substances and effects on the ecosystem. In the fra...

  12. Habitat Scale Mapping of Fisheries Ecosystem Service Values in Estuaries

    OpenAIRE

    Steve J. Jordan; Darrin D. Dantin; Steven P. Ferraro; Timothy G. O’Higgins; Marnita M. Chintala

    2010-01-01

    Little is known about the variability of ecosystem service values at spatial scales most relevant to local decision makers. Competing definitions of ecosystem services, the paucity of ecological and economic information, and the lack of standardization in methodology are major obstacles to applying the ecosystem-services approach at the estuary scale. We present a standardized method that combines habitat maps and habitat–faunal associations to estimate ecosystem service values for recr...

  13. Trace elements distribution in bottom sediments from Amazon River estuary

    International Nuclear Information System (INIS)

    The Amazon River discharges into a dynamic marine environment where there have been many interactive processes affecting dissolved and particulate solids, either those settling on the shelf or reaching the ocean. Trace elemental concentration, especially of the rare earth elements, have been determined by neutron activation analysis in sixty bottom sediment samples of the Amazon River estuary, providing information for the spatial and temporal variation study of those elements. (author). 16 refs, 6 figs, 3 tabs

  14. Seasonal dynamics of turbidity maximum in the Muthupet estuary, India

    Science.gov (United States)

    Priya, K. L.; Jegathambal, P.; James, E. J.

    2015-10-01

    Results are presented of the longitudinal and vertical profiling of salinity and suspended particulate matter (SPM) at the Muthupet estuary, India, during a one year period under widely varying freshwater flow conditions. Freshwater flow was available during post-monsoon and monsoon. An up-estuary shift in the location of estuarine turbidity maxima (ETM) was observed during the transition from post-monsoon to pre-monsoon and further it shifted downstream during the transition from pre-monsoon to monsoon, thereby exhibiting a pronounced seasonal cycle. The salinity intrusion was dependent on the freshwater discharge and was expressed as a power function of freshwater flow, explaining 97% of the variance. The formation of a salt plug in Muthupet estuary and its seasonal dynamics were observed, which is not an identified feature of any of the Indian estuaries studied so far. The geographical positions of salt plug and ETM core were more or less the same during their formation. The occurrence of two ETM during the LW of post-monsoon and the absence of ETM during monsoon explains the strong seasonal variation in the formation of ETM. The primary factor affecting the formation of ETM was identified as the freshwater flow over an annual cycle; the resuspension of sediments by tidal current affecting the formation on a flood/ebb cycle was secondary. The extent of shift of ETM was found to be an inverse logarithmic function of the freshwater discharge. The separation between ETM intrusion and salinity intrusion increased two fold with the increase in ETM intrusion.

  15. Estrategia para la sustentabilidad ambiental

    Directory of Open Access Journals (Sweden)

    Cecilia Erbiti

    2006-01-01

    Full Text Available En el contexto de los postulados conceptuales y metodológicos de la planificación estratégica y de sustentabilidad ambiental, el objetivo de esta investigación es describir el proceso de formulación del Plan de Ordenamiento Territorial del Municipio de Tandil (POTM y analizar su potencialidad para avanzar hacia la sustentabilidad ambiental del sistema. Los resultados de la misma muestran que el POTM no sólo prioriza principios, objetivos y estrategias que materializan las diferentes manifestaciones de la sustentabilidad (económica, social, ecológica y política, sino que la totalidad del Plan se fundamenta en el concepto de desarrollo sostenible y, con ello, se establecen prioridades de actuación que posibilitarán la gestión ambiental urbana. Si bien el POTM muestra una gran potencialidad para avanzar hacia la sustentabilidad del territorio, la implementación y cumplimiento del mismo constituye un fuerte desafío para las autoridades de aplicación.

  16. Leaf litter ecological fate in the Schelde estuary in Belgium

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Two dominant species of Willow (Salix triandra) and Reed(Phragmites australis) along the Schelde estuary (in Belgium) wereselected in this research. The pigments of higher plant was used asbiomarkers, the decomposition process of the two species werestudied after they fall into the Schelde estuary. After statisticalanalysis (Spearman rank order correlation, p<0.05), the results hasshown the decomposition dynamics pattern of the pigments, and thewillow showed different pattern in comparing with the reed, eg.Chlorophyll-a decomposition dynamics for willow is: y1 = 12196x2 -175895x + 1E + 06 + k, R2 = 0.5706 while for reed is: y2 = -37878x2+ 229782x + 734282 + k, R2 = 0.9065. The precise time of the leaflitter spent in the water was also calculated as were less than 24days, 24-37 days, longer than 37 days (willow) and less than 24days, longer than 24 days (reed), the leaf litter fate of the two -Process, Institute of Applied Ecology, Chinese Academy of Sciencesdominant species in the Schelde estuary was also compared.

  17. Dissolved oxygen conditions in northern Gulf of Mexico estuaries

    Science.gov (United States)

    Engle, V.D.; Kevin, Summers J.; Macauley, J.M.

    1999-01-01

    Because deficient dissolved oxygen (DO) levels may have severe detrimental effects on estuarine and marine life, DO has been widely used as an indicator of ecological conditions by environmental monitoring programs. The U.S. EPA's Environmental Monitoring and Assessment Program for Estuaries (EMAP-E) monitored DO conditions in the estuaries of the Gulf of Mexico from 1991 to 1994. DO was measured in two ways: 1)instantaneous profiles from the surface to the bottom were taken during the day, and 2) continuous measurements were taken near the bottom at 15 min intervals for at least 12 h. This information was summarized to assess the spatial distribution and severity of DO conditions in these estuaries. Depending on the criteria used to define hypoxia (DO concentrations usually < 2 mg L-1 or 15 mg L-1) and the method by which DO is measured, we estimate that between 5.2 and 29.3% of the total estuarine area in the Louisianian Province was affected by low DO conditions.

  18. Major hydrogeochemical processes in an Acid Mine Drainage affected estuary

    International Nuclear Information System (INIS)

    Highlights: • Mixing of acid riverine water with alkaline seawater was studied in an estuary. • Combination of data and geochemical tools allowed modeling the water mixing. • The main geochemical processes were identified and for the first time quantified. • Water chemistry is the result of mixing, dissolution-precipitation and sorption. • Main reactions: gypsum and calcite dissolution and Al and Fe solids precipitation. - Abstract: This study provides geochemical data with the aim of identifying and quantifying the main processes occurring in an Acid Mine Drainage (AMD) affected estuary. With that purpose, water samples of the Huelva estuary were collected during a tidal half-cycle and ion–ion plots and geochemical modeling were performed to obtain a general conceptual model. Modeling results indicated that the main processes responsible for the hydrochemical evolution of the waters are: (i) the mixing of acid fluvial water with alkaline ocean water; (ii) precipitation of Fe oxyhydroxysulfates (schwertmannite) and hydroxides (ferrihydrite); (iii) precipitation of Al hydroxysulfates (jurbanite) and hydroxides (amorphous Al(OH)3); (iv) dissolution of calcite; and (v) dissolution of gypsum. All these processes, thermodynamically feasible in the light of their calculated saturation states, were quantified by mass-balance calculations and validated by reaction-path calculations. In addition, sorption processes were deduced by the non-conservative behavior of some elements (e.g., Cu and Zn)

  19. Eelgrass Enhancement and Restoration in the Lower Columbia River Estuary, Period of Performance: Feb 2008-Sep 2009.

    Energy Technology Data Exchange (ETDEWEB)

    Judd, C.; Thom, R; Borde, A. [Pacific Northwest National Laboratory

    2009-09-08

    The purpose of this study was to evaluate the ability to enhance distribution of eelgrass (Zostera marina) in the Columbia River Estuary to serve as refuge and feeding habitat for juvenile salmon, Dungeness crab, and other fish and wildlife. We strongly suspected that limited eelgrass seed dispersal has resulted in the present distribution of eelgrass meadows, and that there are other suitable places for eelgrass to survive and form functional meadows. Funded as part of the Bonneville Power Administration's call for Innovative Projects, we initiated a multistage study in 2008 that combined modeling, remote sensing, and field experimentation to: (1) Spatially predict habitat quality for eelgrass; (2) Conduct experimental plantings; and (3) Evaluate restoration potential. Baseline in-situ measurements and remote satellite observations were acquired for locations in the Lower Columbia River Estuary (LCRE) to determine ambient habitat conditions. These were used to create a habitat site-selection model, using data on salinity, temperature, current velocity, light availability, wave energy, and desiccation to predict the suitability of nearshore areas for eelgrass. Based on this model and observations in the field, five sites that contained no eelgrass but appeared to have suitable environmental conditions were transplanted with eelgrass in June 2008 to test the appropriateness of these sites for eelgrass growth. We returned one year after the initial planting to monitor the success rate of the transplants. During the year after transplanting, we carried out a concurrent study on crab distribution inside and outside eelgrass meadows to study crab usage of the habitat. One year after the initial transplant, two sites, one in Baker Bay and one in Young's Bay, had good survival or expansion rates with healthy eelgrass. Two sites had poor survival rates, and one site had a total loss of the transplanted eelgrass. For submerged aquatic vegetation (SAV) restoration

  20. Rasgos de la literatura apocalíptica en el poema de la bestia y el ángel de José María Pemán

    OpenAIRE

    Madyjewska, Katarzyna

    2006-01-01

    El artículo presenta el Poema de la Bestia y el Ángel, de José María Pemán, como una obra que integra la mayoría de los rasgos de la literatura apocalíptica: su estructura, planteamiento, contenido y procedimientos alegóricos. Este estilo literario no se ciñe sólo a la literatura espiritual, sino que también surge en tiempos de crisis políticas y sociales a lo largo de la historia. En el marco de las turbulentas sacudidas que afectaron a Europa en los primeros decenios del s. XX, el...

  1. Especies leñosas nativas claves para la restauración ecológica del Embalse de Chisacá, Colombia, con base en rasgos importantes de su historia de vida

    OpenAIRE

    Rodríguez Ramírez Natalia; Vargas Orlando

    2006-01-01

    Se determinaron cinco especies nativas leñosas, como claves para la restauración de plantaciones de Pinus patula
    y Corredor ripario potrerizado del embalse de Chisacá (localidad de Usme, Bogotá, Colombia 3.000-3.250
    msnm; 4°08’59’’ N; 74°17’62’’ W), con base en Rasgos de de Historia de Vida (RHV) y otras características de
    especies presentes en estas áreas. Teniendo en cuenta el objetivo del estudio y las características de las áreas
    degradadas se s...

  2. Caracterización de los rasgos esenciales de la identidad profesional de los trabajadores sociales, que integraban el Consejo de Graduados en Trabajo Social de la Provincia de Santa Cruz, durante los años 1970-1980

    Directory of Open Access Journals (Sweden)

    Lorena Lucia Julieta Meoniz

    2014-06-01

    Full Text Available El presente trabajo da cuenta de los avances realizados en la línea de indagación dedicada al estudio de los rasgos de la identidad profesional de los Trabajadores Sociales adscriptos al Consejo de Graduados en Trabajo Social de la Provincia de Santa Cruz durante los años 1970-1980. Para dicho análisis se tuvo en cuenta los datos y materiales aportados por la sistematización de los Libros de Actas N° 1 y 2 del Consejo Profesional de Graduados en Trabajo Social de la Provincia de Santa Cruz, incluyendo asimismo la lectura de los avances teóricos producidos por el equipo de trabajo del proyecto de investigación en el cual participamos como becadas.

  3. Perennial grasses traits as functional markers of grazing intensity in basaltic grasslands of Uruguay Rasgos de gramíneas perennes como marcadores funcionales de la intensidad de pastoreo en pastizales de basalto en Uruguay

    Directory of Open Access Journals (Sweden)

    Martin Jaurena

    2012-12-01

    Full Text Available Natural grasslands in the basaltic region of Uruguay are threatened by an increase in stocking rates and changes in land use. To assess the effect of grazing intensification, plant functional types are proposed as simple tools to aid the monitoring and management of vegetation. In the present study we evaluated the effect of stocking rate increase at community level taking into account plant traits of 23 dominant perennial grass species. In order to identify plant functional types, we determined the grazing response in an experiment with two wethers stocking rates (0.78 and 1.56 livestock units ha-1 quantifying species cover and traits values. Leaf dry matter content (LDMC and specific leaf area (SLA were the traits that best described the perennial grasses response to the stocking rate increase and therefore are suggested to be used as functional markers. Three functional types were identified. Low stocking rates were related to functional type A (tall, warm season species with low SLA and high LDMC and functional type B (tall, cool-season species, with intermediate levels of leaf traits. On the other hand, high stocking rate encouraged functional type C (prostrate, warm season species, with high SLA and low LDMC. The classification of a highly diverse community into three functional types and the selection of traits as functional markers candidates is an innovative approach to develop simple and general methods to diagnosis the state of basaltic grasslands in Uruguay and to advise on its management.Las praderas naturales de la region bas áltica de Uruguay están amenazadas por el incremento de la carga animal y cambios en el uso del suelo. Para evaluar el efecto del pastoreo se han propuesto los grupos funcionales como una herramienta simple para el monitoreo y manejo de la vegetación. El presente estudio evaluó el efecto del incremento de la carga animal considerando rasgos de 23 especies de gramineas perennes dominantes. Para identificar

  4. Rasgos de personalidad, edad, cultura y restricciones hídricas y dietéticas en pacientes en hemodiálisis Personality traits, age, culture and hydric and dietetic restrictions in patients undergoing haemodialysis

    Directory of Open Access Journals (Sweden)

    Ana María Ruiz Vaca

    2011-06-01

    Full Text Available Queda mucho por investigar y comprender alrededor de la interacción entre lo físico y lo mental. Los pacientes sometidos a hemodiálisis debido a su enfermedad, deben cumplir una serie de normas dietéticas, de cuidado de su acceso vascular, etc. Pensamos que los rasgos de la personalidad, la edad, la cultura, pueden influir en la aceptación de la enfermedad de nuestros pacientes renales en tratamiento sustitutivo con hemodiálisis, y por lo consiguiente en el cumplimiento de las normas dietéticas, lo cual se vería reflejado en sus resultados analíticos pre-HD (niveles de potasio, de fósforo, ganancia interdiálisis, aunque también somos conscientes de que pueden influir otras variables, como es el nivel de afectación renal, nivel sociocultural, etc. La muestra del estudio la constituyeron 35 pacientes de la unidad de diálisis de Melilla, de diferentes edades (mayores de 18 años y de ambos sexos. Para conocer los rasgos de personalidad de nuestros pacientes, se les realizó un cuestionario validado de personalidad. Los datos registrados fueron: edad, sexo, cultura, rasgo de personalidad, potasio, fósforo, ganancia interdiálisis. No hemos hallado correlación significativa entre los rasgos de personalidad, la cultura frente a la ganancia de peso interdiálisis, niveles de fósforo y potasio, pero sí hemos hallado correlación significativa negativa entre la variable edad frente a la ganancia interdiálisis y los niveles de fósforo, aunque no así en los niveles de potasio, dé tal manera que se ve reflejado que a mayor edad, presentan menos ganancia interdiálisis y menos niveles de fósforo.Much has still to be investigated and understood about the interaction between the physical and the mental. Patients undergoing haemodialysis because of their illness have to comply with a series of dietetic rules, care of their vascular access, etc. We think that personal traits, age, culture can influence the acceptance of the illness by our

  5. Influence of allochthonous input on autotrophiceheterotrophic switch-over in shallow waters of a tropical estuary (Cochin Estuary), India

    Digital Repository Service at National Institute of Oceanography (India)

    Thottathil, S.D.; Balachandran, K.K.; Gupta, G.V.M.; Madhu, N.V.; Nair, S.

    Institute of Oceanography, Dona Paula, Goa 403004, India Received 26 August 2007; accepted 29 January 2008 Available online 10 February 2008 Abstract Bacterial productivity (BP) and respiration (BR) were examined in relation to primary productivity (PP... the C-cycling in this estuary. These results are of particular relevance to tropical ecosystems in general, where the bulk of world’s river discharges occur. C211 2008 Elsevier Ltd. All rights reserved. Keywords: primary productivity; bacterial...

  6. Residual fluxes of water and nutrient transport through the main inlet of a tropical estuary, Cochin estuary, West Coast, India

    Digital Repository Service at National Institute of Oceanography (India)

    Vinita, J.; Lallu, K.R.; Revichandran, C.; Muraleedharan, K.R.; Jineesh, V.K.; Shivaprasad, A.

    . The strong ebb currents and the increased nutrient concentrations during ebb resulted in the export of all nutrients (except ammonia during spring) into the sea. The findings of this study highlight the consequences of anthropogenic interventions...., Greenberg, A. E., et al. (Eds.), Washington, DC: American Public Health Association. Balachandran, K.K., Laluraj, C.M., Nair, M., Joseph, T., Sheeba, P., et al. (2005). Heavy metal accumulation in a flow restricted tropical estuary. Estuarine, Coastal...

  7. Three-dimensional semi-idealized model for tidal motion in tidal estuaries. An application to the Ems estuary

    Science.gov (United States)

    Kumar, Mohit; Schuttelaars, Henk M.; Roos, Pieter C.; Möller, Matthias

    2016-01-01

    In this paper, a three-dimensional semi-idealized model for tidal motion in a tidal estuary of arbitrary shape and bathymetry is presented. This model aims at bridging the gap between idealized and complex models. The vertical profiles of the velocities are obtained analytically in terms of the first-order and the second-order partial derivatives of surface elevation, which itself follows from an elliptic partial differential equation. The surface elevation is computed numerically using the finite element method and its partial derivatives are obtained using various methods. The newly developed semi-idealized model allows for a systematic investigation of the influence of geometry and bathymetry on the tidal motion which was not possible in previously developed idealized models. The new model also retains the flexibility and computational efficiency of previous idealized models, essential for sensitivity analysis. As a first step, the accuracy of the semi-idealized model is investigated. To this end, an extensive comparison is made between the model results of the semi-idealized model and two other idealized models: a width-averaged model and a three-dimensional idealized model. Finally, the semi-idealized model is used to understand the influence of local geometrical effects on the tidal motion in the Ems estuary. The model shows that local convergence and meandering effects can have a significant influence on the tidal motion. Finally, the model is applied to the Ems estuary. The model results agree well with observations and results from a complex numerical model.

  8. Land use and nitrogen loading in seven estuaries along the southern Gulf of St. Lawrence, Canada

    Science.gov (United States)

    McIver, Reba; Milewski, Inka; Lotze, Heike K.

    2015-11-01

    Nitrogen loading from coastal watersheds is a principal factor associated with the decline in eelgrass bed health and cover in estuaries worldwide. We apply the Nitrogen Loading Model (NLM) framework developed in Waquoit Bay, Massachusetts to 7 estuaries in eastern New Brunswick. Using watershed-specific information on human population, wastewater production, atmospheric deposition, and land use in each watershed we estimate annual input of Total Dissolved Nitrogen (TDN) from point and non-point sources. We also estimate flushing time of each estuary using available hydrodynamic and bathymetric data incorporated in a tidal prism model. Finally, we validate the NLM results by testing the link between estimated nitrogen loading, flushing time and nitrogen signals in eelgrass tissue including nitrogen content and stable isotopes. Overall, total nitrogen load (kg TDN yr-1) was strongly dependent on watershed and estuary size, while loading rate per unit watershed area (yield) was linked to watershed population density. Atmospheric deposition was the largest contributor of nitrogen to all estuaries except one, where seafood processing effluent was the greatest source. Stable isotope analysis of eelgrass tissue reflected this distinction, with high δ15N values of 8-10‰ related to high wastewater loading, compared to 2-6.5‰ in the other estuaries that receive proportionally more atmospheric deposition. Tissue nitrogen content was positively related to nitrogen yields and loading rate per volume of estuary, highlighting the influence of variable watershed:estuary size ratio. Multiple regression analysis identified a significant interaction between nitrogen yield and flushing time on eelgrass tissue nitrogen content and isotopes, pointing to the mitigating effect an estuary's quick flushing time can have on the expression of nitrogen enrichment in primary producers. The compilation of new information on nitrogen loading to east Canadian estuaries is a novel

  9. Optical properties of a tropical estuary during wet and dry conditions in the Nha Phu estuary, Khanh Hoa Province, south-east Vietnam

    DEFF Research Database (Denmark)

    Lund-Hansen, Lars Chresten; Hai, Doan Nhu; Lam, Nguyen Ngoc; Nielsen, Morten Holtegaard

    2010-01-01

    There has been a strong research focus on optical properties in temperate estuaries but very much less in tropical estuaries. These properties comprise light and beam attenuation dominated by suspended particulate matter, Chl a, and CDOM. Spatially and temporally distributed data on optical prope...... temperate estuaries, was the episodic character with days of strong rainfall followed by longer periods of dry weather. All sampling, both wet and dry, was carried out in the dry season which implies a less definitive perception of wet and dry seasons....

  10. The dynamics of a frictionally-dominated Amazonian estuary

    Directory of Open Access Journals (Sweden)

    Nils Edvin Asp

    2012-09-01

    Full Text Available The hydrodynamics, morphology and sedimentology of the Taperaçu estuary were investigated. This is one of several estuaries located within the largest mangrove fringe in the world, bordering the Amazon region, subject to a macrotidal regime and regionally atypical negligible fresh water supply. The results reveal widespread sand banks that occupy the central portion of the estuarine cross-section. Well-sorted very fine sandy sediments of marine origin prevail. Shorter flood phases, with substantially higher current velocities, were observed in the upper sector of Taperaçu, as expected for a shallow, friction-dominated estuary. However, ebb domination can be expected for estuaries with large associated mangrove areas and substantial estuarine infilling, both of which situations occur on the Taperaçu. The tidal asymmetry favoring flood currents could be the result of the absence of an effective fluvial discharge. Furthermore, it was observed that the Taperaçu is connected by tidal creeks to the neighboring Caeté estuary, allowing a stronger flux during the flood and intensifying the higher flood currents. As a whole, the results have shown a complex interaction of morphological aspects (friction, fluvial drainage, connections with neighbor estuaries, infilling and large storage area in determining hydrodynamic patterns, thus improving the understanding of Amazon estuaries.A hidrodinâmica, morfologia e sedimentologia do estuário do Taperaçu foram investigadas. Este é um entre vários estuários do litoral amazônico que integram a maior extensão contínua de manguezais do mundo, apresentando uma descarga de água doce muito reduzida, atípica para a região. Os resultados revelam grandes bancos arenosos que ocupam em grande parte a porção central do estuário. Areias muito finas e bem selecionadas de origem marinha prevalecem. Fases de enchente mais curtas, com velocidades de corrente substancialmente mais altas, são observadas na por

  11. Nonlinear Elasticity in a Deforming Ambient Space

    Science.gov (United States)

    Yavari, Arash; Ozakin, Arkadas; Sadik, Souhayl

    2016-07-01

    In this paper, we formulate a nonlinear elasticity theory in which the ambient space is evolving. For a continuum moving in an evolving ambient space, we model time dependency of the metric by a time-dependent embedding of the ambient space in a larger manifold with a fixed background metric. We derive both the tangential and the normal governing equations. We then reduce the standard energy balance written in the larger ambient space to that in the evolving ambient space. We consider quasi-static deformations of the ambient space and show that a quasi-static deformation of the ambient space results in stresses, in general. We linearize the nonlinear theory about a reference motion and show that variation of the spatial metric corresponds to an effective field of body forces.

  12. Monsoons and habitat influence trophic pathways and the importance of terrestrial-marine linkages for estuary sharks

    OpenAIRE

    Yeung, JWY; Lam, VYY; Williams, GA; Wai, TC; Leung, KMY; Dudgeon, D

    2012-01-01

    Tropical estuaries often receive enhanced fluxes of terrestrial derived organic matter and phytoplankton during the wet season, and such monsoonal events may significantly influence the trophic dynamics of these systems. This study examined spatio-temporal terrestrial-marine linkages in a tropical estuary, the Pearl River Estuary (PRE), southern China, by investigating trophic pathways leading to estuary sharks. We investigated spatial (inshore vs. offshore) and seasonal (wet vs. dry season) ...

  13. Hidrogeología ambiental

    OpenAIRE

    Auge, Miguel

    2004-01-01

    La finalidad de este libro es introducir a aquellos que trabajan en agua subterránea, en una temática relativamente moderna pero que en los últimos 15 a 20 años, ha concentrado la mayor demanda laboral de geólogos en los países desarrollados del Hemisferio Norte. En el tomo I se analiza la relación del agua subterránea con el ambiente, tratando especialmente, el origen, las características, y los procesos de contaminación. Se describe la relación agua superficial-subterránea y su incidencia e...

  14. Pediatria ambiental: um tema emergente

    Directory of Open Access Journals (Sweden)

    Patricia M. Valenzuela

    2011-04-01

    Full Text Available OBJETIVO: Revisar os artigos mais relevantes sobre a pediatria ambiental, seus efeitos potenciais para a saúde e, especialmente, seus avanços na prevenção. FONTES DOS DADOS: Foi realizada uma pesquisa utilizando as bases de dados MEDLINE/PubMed e SciELO. Foram revisados artigos de 1990 a 2010, além de capítulos de livros relacionados à pediatria ambiental. SÍNTESE DOS DADOS: Há uma variedade significativa de fatores que tornam as crianças altamente vulneráveis à exposição a riscos ambientais, associados principalmente ao consumo comparativamente maior de água, comida e ar por parte da criança, em relação ao seu peso corporal. De acordo com a Organização Mundial de Saúde, mais de 3 milhões de crianças menores de 5 anos morrem devido a doenças relacionadas ao meio ambiente. Aproximadamente 30-40% das doenças pediátricas estão relacionadas a fatores ambientais. As crianças estão constantemente expostas a vários riscos ambientais para a saúde, dentre os quais se destacam: água contaminada, falta de condições adequadas de saneamento, poluição do ar, vetores de doenças, perigos químicos, injúrias e acidentes. CONCLUSÕES: Atualmente, os pediatras são desafiados a tratar das necessidades de saúde ligadas à pediatria ambiental. A história pediátrica deve ser mais abrangente, acrescentando-se questões pontuais que ajudem a identificar potenciais riscos ambientais. A conscientização e o entendimento sobre os efeitos nocivos das várias condições ambientais e o conhecimento sobre as medidas de prevenção relacionadas resultarão em intervenções oportunas e adequadas que melhorarão a saúde e o desenvolvimento das nossas crianças.

  15. Responsabilidades municipales en materia ambiental

    OpenAIRE

    Ignacio Pichardo Pagaza

    2009-01-01

    Los municipios tienen una responsabilidad directa, inmediata e ineludible hacia el medio ambiente que hasta hace pocos años no reconocían como pri mor dial sino como una función secundaria. Hoy es más que una obligación jurídica, es un compromiso so cial del nivel de gobierno más cercano a la sociedad. Este trabajo reflexiona en torno a las responsabilidades que la Constitución política impone de manera exclusiva a los municipios y que por su naturaleza tienen efectos directos en el medio amb...

  16. E-Estuary: Developing a Decision Support System for Coastal Management in the Conterminous United States (IAHR)

    Science.gov (United States)

    Ready access to geographic information is needed to support management decisions for estuaries at local, state, regional, and national scales. The U.S. Environmental Protection Agency (US EPA) is developing e-Estuary, a decision-support system for coastal management. E-Estuary ...

  17. Water pollution in estuaries and coastal zones. (Latest citations from the NTIS bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-02-01

    The bibliography contains citations concerning the studies of water pollution in estuaries and coastal zones. Citations examine the development, management, and protection of estuary and coastal resources. Topics include pollution sources, environmental monitoring, water chemistry, eutrophication, models, land use, government policy, and laws and regulations. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  18. Second international symposium on the biogeochemistry of model estuaries: Estuarine processes in global change

    Energy Technology Data Exchange (ETDEWEB)

    1991-12-31

    This report consists of abstracts of papers presented at the symposium of Biogeochemistry. The main topics discussed at the meeting are; nutrient and mineral cycling, trace element distribution, sources and sinks of estuaries, sedimentation, importance of organic matter, and other biogeochemical processes of estuaries.

  19. The nature and distribution of particulate matter in the Mandovi Estuary, central west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Kessarkar, P.M.; Rao, V.P.; Shynu, R.; Mehra, P.; Viegas, B.E.

    and biogenic particles occur everywhere in the estuary. Diatoms are the most common and are of marine type at the sea-end and freshwater dominated at river-end stations of the estuary. SPM is characterized by kaolinite- and smectite-rich clay mineral suites...

  20. Benthic macrofaunal dynamics and environmental stress across a salt wedge Mediterranean estuary.

    Science.gov (United States)

    Nebra, Alfonso; Alcaraz, Carles; Caiola, Nuno; Muñoz-Camarillo, Gloria; Ibáñez, Carles

    2016-06-01

    The spatial distribution of benthic macroinvertebrate community in relation to environmental factors was studied along the Ebro Estuary (NE Iberian Peninsula), a salt wedge Mediterranean estuary. Both ordination methods and generalized additive models were performed to identify the different benthic assemblages and their relationship to abiotic factors. Our results showed a strong relationship between macrofaunal assemblages and the predominant environmental gradients (e.g. salinity); thus revealing spatial differences in their structure and composition. Two different stretches were identified, namely the upper (UE) and the lower Ebro Estuary (LE). UE showed riverine characteristics and hence was colonized by a freshwater community; whereas LE was influenced by marine intrusion and sustained a complex marine-origin community. However, within each stretch, water and sediment characteristics played an important role in explaining species composition differences among sampling stations. Moreover, outcomes suggested a total species replacement pattern, instead of the nestedness pattern usually associated with well-mixed temperate estuaries. The sharp species turnover together with the estuarine stratification point out that the Ebro Estuary is working, in terms of ecological boundaries, under an ecotone model. Finally, despite obvious differences with well mixed estuaries (i.e. lack of tidal influence, stratification and species turnover), the Ebro Estuary shares important ecological attributes with well-mixed temperate estuaries. PMID:27062106

  1. Concentration and Distribution of Hydrophobic Organic Contaminants and Metals in the Estuaries of Ukraine

    Science.gov (United States)

    In this baseline study of Ukrainian estuaries, sediments and organisms from the Dnieper and Boh estuaries and Danube Delta on the mainland, Sevastopol and Balaklava Bays on the Crimean Peninsula, and coastal Black Sea along the Crimean Peninsula were collected in 2006. Contamina...

  2. 76 FR 8345 - Endangered and Threatened Species; Recovery Plan Module for Columbia River Estuary Salmon and...

    Science.gov (United States)

    2011-02-14

    ... including water withdrawals, flow regulation, natural climate cycles, and human contributions to global... the estuary and plume have also degraded water quality. Contaminants found in the estuary and plume... throughout the entire life cycle. The salmonid life cycle includes spawning and rearing in the...

  3. Mixing and flushing time scales in the Azhikode Estuary, southwest coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Revichandran, C.; Pylee, A.

    Flushing time scales of the Azhikode Estuary, Kerala, India showed pronounced dry season and wet season signals as well as large inter-annual variation. Cumulative flushing time of the estuary varies from 4.8 tide cycles in April to 1.22 tide cycles...

  4. Modelling the transverse distribution of velocity and suspended sediment in tidal estuaries

    NARCIS (Netherlands)

    Huijts, K.M.H.

    2011-01-01

    An estuary is a semi-enclosed coastal body of water which has a free connection with the open sea and within which sea water is measurably diluted with fresh water derived from land drainage. Examples are the Western Scheldt River Estuary and the Chesapeake Bay. Within these environments complex pat

  5. The effects of changes to estuarine hydrology on system phosphorous retention capacity: The Mondego estuary, Portugal

    DEFF Research Database (Denmark)

    Lillebo, A. I.; Otero, M.; Coelho, J. P.;

    2012-01-01

    The Mondego estuary is a mainly polyhaline estuary in central Portugal in which eutrophication increased during the last decades of the 20th century. In 1998 the system hydrology was changed, aiming to reverse the eutrophication process. A long environmental monitoring database showed that the me...

  6. Sub-tidal water-level oscillations in the Mandovi estuary, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Shetye, S.R.; Vijith, V.

    at periods longer than two days. We then examine the causes behind the variability using data on wind and current measured near the mouth of the estuary. The main channel of the estuary is 50 km long and March–April is a period when local winds are weak. Our...

  7. Salt intrusion in multi-channel estuaries: a case study in the Mekong Delta, Vietnam

    Directory of Open Access Journals (Sweden)

    A. D. Nguyen

    2006-01-01

    Full Text Available There is a well-tested theory for the computation of salt intrusion in alluvial estuaries that is fully analytical and predictive. The theory uses analytical equations to predict the mixing behaviour of the estuary based on measurable quantities, such as channel topography, river discharge and tidal characteristics. It applies to single-channel topographies and estuaries that demonstrate moderate tidal damping. The Mekong delta is a multi-channel estuary where the tide is damped due to a relatively strong river discharge (in the order of 2000 m3/s, even during the dry season. As a result the Mekong is a strongly riverine estuary. This paper aims to test if the theory can be applied to such a riverine multi-channel estuary, and to see if possible adjustments or generalisations need to be made. The paper presents salt intrusion measurements that were done by moving boat in 2005, to which the salt intrusion model was calibrated. The theory has been expanded to cater for tidal damping. Subsequently the model has been validated with observations made at fixed locations over the years 1998 and 1999. Finally it has been tested whether the Mekong calibration fits the overall predictive equations derived in other estuaries. The test has been successful and led to a slight adjustment of the predictive equation to cater for estuaries that experience a sloping bottom.

  8. Transport of fallout and reactor radionuclides in the drainage basin of the Hudson River estuary

    International Nuclear Information System (INIS)

    The transport and fate of Strontium 90, Cesium 137 and Plutonium 239, 240 in the Hudson River Estuary is discussed. Rates of radionuclide deposition and accumulation over time and space are calculated for the Hudson River watershed, estuary, and continental shelf offshore. 37 references, 7 figures, 15 tables

  9. Estuary Data Mapper: A virtual portal to coastal data informing environmental management decisions

    Science.gov (United States)

    The Estuary Data Mapper (EDM) is a free, interactive graphical application under development at the US EPA that allows environmental researchers and managers to quickly and easily retrieve, view and save subsets of online US coastal estuary-related data. Accessible data include ...

  10. Residual estuarine circulation in the Mandovi, a monsoonal estuary: A three-dimensional model study

    Science.gov (United States)

    Vijith, V.; Shetye, S. R.; Baetens, K.; Luyten, P.; Michael, G. S.

    2016-05-01

    Observations in the Mandovi estuary, located on the central west coast of India, have shown that the salinity field in this estuary is remarkably time-dependent and passes through all possible states of stratification (riverine, highly-stratified, partially-mixed and well-mixed) during a year as the runoff into the estuary varies from high values (∼1000 m3 s-1) in the wet season to negligible values (∼1 m3 s-1) at end of the dry season. The time-dependence is forced by the Indian Summer Monsoon (ISM) and hence the estuary is referred to as a monsoonal estuary. In this paper, we use a three-dimensional, open source, hydrodynamic, numerical model to reproduce the observed annual salinity field in the Mandovi. We then analyse the model results to define characteristics of residual estuarine circulation in the Mandovi. Our motivation to study this aspect of the Mandovi's dynamics is derived from the following three considerations. First, residual circulation is important to long-term evolution of an estuary; second, we need to understand how this circulation responds to strongly time-dependent runoff forcing experienced by a monsoonal estuary; and third, Mandovi is among the best studied estuaries that come under the influence of ISM, and has observations that can be used to validate the model. Our analysis shows that the residual estuarine circulation in the Mandovi shows four distinct phases during a year: a river like flow that is oriented downstream throughout the estuary; a salt-wedge type circulation, with flow into the estuary near the bottom and out of the estuary near the surface restricted close to the mouth of the estuary; circulation associated with a partially-mixed estuary; and, the circulation associated with a well-mixed estuary. Dimensional analysis of the field of residual circulation helped us to establish the link between strength of residual circulation at a location and magnitude of river runoff and rate of mixing at the location. We then

  11. Distribution and sources of aliphatic hydrocarbons and fatty acids in surface sediments of a tropical estuary south west coast of India (Cochin estuary)

    Digital Repository Service at National Institute of Oceanography (India)

    Gireeshkumar, T.R.; Deepulal, P.M.; Chandramohanakumar, N.

    Surface sediments samples from the Cochin estuary were measured for elemental, stable isotopic and molecular biomarkers (aliphatic hydrocarbons and fatty acids) to study the sources and distribution of sedimentary organic matter. Concentrations...

  12. Dissolved organic matter (DOM) export to a temperate estuary: Seasonal variations and implications of land use

    DEFF Research Database (Denmark)

    Stedmon, C. A.; Markager, S.; Søndergaard, M.;

    2006-01-01

    Inputs of dissolved carbon, nitrogen, and phosphorus were assessed for an estuary and its catchment (Horsens, Denmark). Seasonal patterns in the concentrations of DOM in the freshwater supply to the estuary differed depending on the soil and drainage characteristics of the area. In streams draining......, and the percentage of catchment area used for agriculture. Colored DOM (CDOM) loading measurements were found to be a good predictor of dissolved organic carbon (DOC) loading across the different subcatchments, offering a rapid and inexpensive alternative of operationally monitoring DOC export. For...... all the dissolved nutrient inputs to the estuary, dissolved inorganic nitrogen (DIN) and dissolved organic phosphorus dominated the loadings. Although 81% of the nitrogen annually supplied to the estuary was DIN, 83% of the nitrogen exported from the estuary was dissolved organic nitrogen (DON...

  13. Ambiguities in the classification of Cochin Estuary, West Coast of India

    Directory of Open Access Journals (Sweden)

    A. Shivaprasad

    2013-03-01

    Full Text Available Cochin Estuary is a unique complex system along Indian coastline with a widespread area at the upstream. The fluctuations in salinity are of extreme kind ranging from entirely riverine to entirely saline. The high runoff months are characterized by monsoonal spells causing intense flushing. During the peak dry period, the runoff is less but steady providing a stable environment. River runoff is controlled by short term variations rather than long term variations. Using large comprehensive data sets, an attempt is made to evaluate several classification schemes for the estuary. The existing methods proved to be insufficient to represent the real salient features of this typical estuary. Arguments are also presented to illustrate the confusion in the names by which the estuary is commonly known. Therefore, a new nomenclature is proposed as "Cochin Monsoonal Estuarine Bay" embodying the physiographic, hydrographic and biological features of the estuary.

  14. Sedimentary fabrics of the macrotidal, mud-dominated, inner estuary to fluvio-tidal transition zone, Petitcodiac River estuary, New Brunswick, Canada

    Science.gov (United States)

    Shchepetkina, Alina; Gingras, Murray K.; Zonneveld, John-Paul; Pemberton, S. George

    2016-03-01

    The study provides a detailed description of mud-dominated sedimentary fabrics and their application for the rock record within the inner estuary to the fluvial zone of the Petitcodiac River estuary, New Brunswick, Canada. Sedimentological characteristics and facies distributions of the clay- and silt-rich deposits are reported. The inner estuary is characterized by thick accumulations of interbedded silt and silty clay on intertidal banks that flank the tidally influenced channel. The most common sedimentary structures observed are parallel and wavy lamination, small-scale soft-sediment deformation with microfaults, and clay and silt current ripples. The tidal channel contains sandy silt and clayey silt with planar lamination, massive and convolute bedding. The fluvio-tidal transition zone is represented by interbedded trough cross-stratified sand and gravel beds with planar laminated to massive silty mud. The riverine, non-tidal reach of the estuary is characterized by massive, planar tabular and trough cross-stratified gravel-bed deposits. The absence of bioturbation within the inner estuary to the fluvio-tidal transition zone can be explained by the following factors: low water salinities (0-5 ppt), amplified tide and current speeds, and high concentrations of flocculated material in the water body. Notably, downstream in the middle and outer estuary, bioturbation is seasonally pervasive: in those locales the sedimentary conditions are similar, but salinity is higher. In this study, the sedimentological (i.e., grain size, bedding characters, sedimentary structures) differences between the tidal estuary and the fluvial setting are substantial, and those changes occur over only a few hundred meters. This suggests that the widely used concept of an extensive fluvio-tidal transition zone and its depositional character may not be a geographically significant component of fluvial or estuary deposits, which can go unnoticed in the study of the ancient rocks.

  15. Feeding preferences of estuarine mysids Neomysis integer and Rhopalophthalmus tartessicus in a temperate estuary (Guadalquivir Estuary, SW Spain)

    OpenAIRE

    Vilas, C.; Drake, P.; Fockedey, N.

    2008-01-01

    Mysid shrimps are an important component of estuarine food webs because they play a key role in energy transfer as intermediate prey. We investigated the seasonal, tidal and depth specific variation in the diet of the estuarine mysids Neomysis integer and Rhopalophthalmus tartessicus and explored its implications for the planktonic community structure of a temperate estuary (Guadalquivir Estuary, SW Spain). Neomysis integer is an opportunistic omnivore feeding mainly on mesozooplankton and on...

  16. Lattice Boltzmann Hydrodynamic and Transport Modeling of Everglades Mangrove Estuaries

    Science.gov (United States)

    Sukop, M. C.; Engel, V.

    2010-12-01

    Lattice Boltzmann methods are being developed and applied to simulate groundwater and surface water flows, and heat, solute, and particle transport. Their ability to solve Navier-Stokes, St. Venant, or Darcy equations with closely coupled solute transport and density-dependent flow effects in geometrically complex domains is attractive for inverse modeling of tracer release data and forward modeling of carbon transport in mangrove estuaries under various future conditions. Key physical processes to be simulated include tidal cycles, storm surge, sea level change, variable upstream stage, subsurface groundwater inputs, and precipitation/recharge and their effects on estuary salinity and carbon transport in the estuaries and groundwater beneath the mangroves. Carbon sources and storage in the aquifer and exchanges at the mangrove-estuary interface and carbon transformations in the water column also need to be simulated. Everglades tidal mangrove estuaries are characterized by relatively high velocity (approaching 1 m s-1) tidal flows. The channels are generally less than 2 m in depth. Tidal fluctuations approach 2 m leading to significant areas of periodic inundation and emergence of oyster beds, shell beaches, mangrove root masses, and sandy beaches. Initial models are two-dimensional, although a three-dimensional model explicitly incorporating bathymetry, density-dependent flow, and wind-driven circulation could be developed. Preliminary work highlights some of the abilities of early models. A satellite image of a 64-km2 area surrounding a CO2 flux tower is used to provide the model geometry. Model resolution is 15 m per grid node. A sinusoidal tidal stage variation and constant, high salinity are applied to the Gulf side of the model while a constant stage (corresponding to mean tide), zero salinity boundary is applied on the inland side. The Navier-Stokes equations coupled with the advection-diffusion equation are solved in the open channels. The mangrove areas

  17. Morphodynamic evolution of the Xiaoqing River mouth:a Huanghe River-derived mixed energy estuary

    Institute of Scientific and Technical Information of China (English)

    HUANG Haijun; LIU Yanxia; QIU Zhongfeng

    2012-01-01

    In an estuary,tidal,wave and other marine powers interact with the coast in different ways and affect estuary morphology as well as its evolution.In the Huanghe(Yellow)River estuaries and nearby delta,there are many small sediment-affected estuaries with a unique morphology,such as the Xiaoqing River estuary.In this study,we investigated the special evolution and genetic mechanism of the Xiaoqing River estuary by analyzing graphic and image data with a numerical simulation method.The results show that NE and NE-E tide waves are the main driving force for sandbar formation.Sediment shoals have originated from huge amounts of sediment from the Huanghe River,with consequent deposition at the Xiaoqing River mouth.The lateral suspended sediments beyond the river mouth move landward.Siltation takes place on the northern shoreline near the river mouth whereas erosion occurs in the south.The deposits come mainly from scouring of the shallow seabed on the northern side of the estuary.Storm surges speed up deposition in the estuary.Development of the sediment shoals has occurred in two steps involving the processes of growth and further southward extension.Although the southward shift increases the river curvature and length,the general eastward orientation of the estuary is unlikely to change.Processes on the adjacent shorelines do not affect the development of the sediment shoals.The study presents a morphodynamic evolutionary model for the Xiaoqing River estuary,with a long-term series cycle,within which a relatively short cycle occurs.

  18. Heavy Metals (Cd, Cu, Cr, Pb and Zn) in Meretrix meretrix Roding, Water and Sediments from Estuaries in Sabah, North Borneo

    Science.gov (United States)

    Abdullah, Mohd. Harun; Sidi, Jovita; Aris, Ahmad Zaharin

    2007-01-01

    Concentrations of heavy metals (Cd, Cu, Cr, Pb and Zn) in tissues of Meretrix meretrix Roding (M. meretrix R.), water and sediments from two estuaries were determined. One estuary is located in an urban area of Kota Kinabalu (Likas estuary) and the other in a rural district of Kota Belud (Kota Belud estuary), where both are in Sabah, North of…

  19. The main phosphorous sources in the Changjiang estuary

    Institute of Scientific and Technical Information of China (English)

    YANG Dongfang; WANG Fan; MIAO Zhenqing; CHEN Yongli; TONG Yuanzheng

    2008-01-01

    Analysis using historical data on the phosphate sources in Changjiang (Yangtze River) estuary show that phosphate was supplied equally from the east, south, west and north of the estuary. These sources include the Changjiang River, the Taiwan Warm Current (TWC), a cyclone-type eddy, and the 32°N Upwelling, supplying different phosphates in different times, ways and intensities. The magnitude of their supplying phosphate concentration was related with the size in the order of the Changjiang River < the TWC < the 32°N Upwelling < the cyclone-type eddy, and the duration of the supplying was: the Changjiang River the TWC the cyclone-type eddy the 32°N Upwelling. The four sources supplied a great deal of phosphate so that the phosphate concentration in the estuary was kept above 0.2 μmol/L in previous years, satisfying the phytoplankton growth. The horizontal and vertical distribution of the phosphate concentration showed that near shallow marine areas at 122°E/31°N, the TWC in low nutrient concentration became an upwelling through sea bottom and brought up nutrients from sea bottom to marine surface. In addition, horizontal distribution of phosphate concentration was consistent with that of algae: Rhizosolenia robusta, Rhizosolenia calcaravis and Skeletonema, which showed that no matter during high water or low water of Changjiang River, these species brought by the TWC became predominant species. Therefore, the authors believe that the TWC flowed from south to north along the coast and played a role in deflecting the Changjiang River flow from the southern side.

  20. Phosphorous speciation in surface sediments of the Cochin estuary.

    Science.gov (United States)

    Gireeshkumar, T R; Deepulal, P M; Chandramohanakumar, N

    2013-03-01

    Sequential chemical extraction using chelating agents were used to study the P dynamics and its bioavailability along the surface sediments of the Cochin estuary (southwest coast of India). Sediments were analyzed for major P species (iron bound P, calcium bound P, acid soluble organic P, alkali soluble organic P and residual organic P), Fe, Ca, total carbon, organic carbon, total nitrogen and total sulfur contents. An abrupt increase in the concentration of dissolved inorganic P with increasing salinity was observed in the study region. Iron-bound P exhibited a distinct seasonal pattern with maximum values in the monsoon season when fresh water condition was prevailed in the estuary. As salinity increased, the percentage of iron-bound P decreased, while that of calcium-bound P and total sedimentary sulfur increased. C/P and N/P ratios were low which indicate that large amounts of organic matter enriched with P tend to accumulate in surface sediments. The high organic P contribution in the sedimentary P pool may indicate high organic matter load with incomplete mineralization, as well as comparatively greater percentage of humic substance and resistant organic compounds. Principal component analysis is employed to find the possible processes influencing the speciation of P in the study region and indicate the following processes: (1) the spatial and seasonal variations of calcium bound P and acid soluble organic P was mainly controlled by sediment texture and organic carbon content, (2) sediment redox conditions control the distribution of iron bound P and (3) the terrigenous input of organic P is a significant processes controlling total P content in surface sediments. The bioavailable P was very high in the surface sediments which on an average accounts for 59 % in the pre-monsoon, 65 % in the monsoon and 53 % in the post-monsoon seasons. The surface sediments act as a potential internal source of P in the Cochin estuary. PMID:22843296

  1. Occurrence of Anaerobic Ammonium Oxidation in the Yangtze Estuary

    Science.gov (United States)

    Hou, L.

    2013-12-01

    Over the past several decades, a large quantity of reactive nitrogen has been transported into the Yangtze estuarine and coastal water, due to intense human activities in the Yangtze River Basin. At present, it annually receives a high load of anthropogenic inorganic nitrogen (about 1.1 × 1011 mol N) from increased agricultural activities, fish farming, and domestic and industrial wastewater discharge in the Yangtze River Basin, consequently leading to severe eutrophication and frequent occurrences of harmful algal blooms in the estuary and adjacent coastal areas. Hence, the microbial nitrogen transformations are of major concern in the Yangtze Estuary. Anaerobic ammonium oxidation (anammox) has been reported to play a significant role in the removal of reactive nitrogen in aquatic ecosystems. In this study, the occurrences of anammox bacteria and associated activity in the Yangtze Estuary were evidenced with molecular and isotope-tracing techniques. It is observed that the anammox bacteria at the study area mainly consisted of Candidatus Scalindua, Brocadia, Kuenenia. Salinity was found to be a key environmental factor controlling distribution and diversity of the anammox bacterial community at the estuarine ecosystem. Also, temperature and organic carbon had significant influences on anammox bacterial biodiversity. Q-PCR assays of anammox bacteria indicated that their abundance had a range of 2.63 ×106 - 9.48 ×107 copies g-1 dry sediment, with high spatiotemporal heterogeneity. The potential anammox activities measured in the present work varied between 0.94 - 6.61nmol N g-1 dry sediment h-1, which were related to temperature, nitrite and anammox bacterial abundance. On the basis of the 15N tracing experiments, the anammox process was estimated to contribute 6.6 - 12.9 % to the total nitrogen loss whereas the remainder was attributed to denitrification.

  2. Environmental monitoring of the Zhujiang Estuary and its coastal waters

    Institute of Scientific and Technical Information of China (English)

    J. C. Chen(陈介中); L. Dong; L. A. Wong; G. W. Heinke

    2002-01-01

    The Zhujiang (Pearl River ) Estuary is a complex water system whose catchments basin coveers a very large part of southern China. The large quantity of fresh water carried by the river system flows into the northern coast of the South China Sea through its eight inlets. The Zhujiang River Delta has experienced the fastest economic growth in China during the past two decades. Rapid population expansion and increased industrial development coupled with insufficient waste management turned the Zhujiang Estuary into waste disposal channels just before entering the coastal waters. The water quality of the estuaries and the coastal oceans has become polluted. Dttfing the past two years, an intensive study and monitoring efforts of the pollutions of these waters have been made. A systematic and integrated monitoring task including shore-based measurements, shipboard in-situ measurements, and satellite and radar remote sensing surveys has been completed. Conprehensive collection of physical,chemical and biological parameters has been accomplished and a database has been established. Unlike the previous large scale-monitoring task in which the various pollutant concentrations were the objective,the present study aims to understand the process of the pollution from their initial disposal to their final states. The understanding of the processes makes it possible to evaluate the severity of the pollution with respect to the sustainability. Also the objective is to incorporate these processes into the mathematical models from which a predictive capability of the pollution situation can be realized. The present presentation will describe the planning, methodology and the results of this effort.

  3. Oil spill trajectory analysis for the Calcasieu Estuary

    International Nuclear Information System (INIS)

    A three-dimensional hydrodynamic model (H3D) was used to determine how oil spills might travel and spread within the Calcasieu River Estuary which has heavy oil traffic. The Calcasieu River is located in the southwest corner of the State of Louisiana and houses valuable wetlands that provide both commercial and recreational fishing and wildlife value to the area. These wetlands also filter water and protect Louisiana's coast areas from hurricane storm surges. An oil spill would damage areas of marshes that would have devastating effects on the entire ecological system within the estuary. A Trajectory Analysis Planner (TAP) H3D computer model is under development by the Hazardous Materials Response Division of the National Oceanic and Atmospheric Administration (NOAA). TAP is a statistical planning tool that randomly samples historical hydrodynamic, hydrology and climatological data, to build up a database with biological and cleanup resource information. TAP can be used to predict which sites within the estuarine system will be most susceptible to oil spills of varying magnitudes, materials and locations. TAP can also estimate the time available for mitigation and remedial actions before the spill can impact the site. Hydrodynamics in the Calcasieu estuary is a combination of processes such as saltwater intrusion and response to water level fluctuations at an open boundary, as well as lake dynamics. H3D provides the three components of velocity, plus scalar quantities such as water levels, temperature and salinity distribution on a Cartesian three-dimensional grid. TAP was tested for spills of kerosene, non-weathering oil, crude oil, and gasoline and was able to perform reliable spill trajectory analysis. 12 refs., 9 figs

  4. Aggregate Settling Velocities in San Francisco Estuary Margins

    Science.gov (United States)

    Allen, R. M.; Stacey, M. T.; Variano, E. A.

    2015-12-01

    One way that humans impact aquatic ecosystems is by adding nutrients and contaminants, which can propagate up the food web and cause blooms and die-offs, respectively. Often, these chemicals are attached to fine sediments, and thus where sediments go, so do these anthropogenic influences. Vertical motion of sediments is important for sinking and burial, and also for indirect effects on horizontal transport. The dynamics of sinking sediment (often in aggregates) are complex, thus we need field data to test and validate existing models. San Francisco Bay is well studied and is often used as a test case for new measurement and model techniques (Barnard et al. 2013). Settling velocities for aggregates vary between 4*10-5 to 1.6*10-2 m/s along the estuary backbone (Manning and Schoellhamer 2013). Model results from South San Francisco Bay shoals suggest two populations of settling particles, one fast (ws of 9 to 5.8*10-4 m/s) and one slow (ws of < 1*10-7 to 1.4*10-5 m/s) (Brand et al. 2015). While the open waters of San Francisco Bay and other estuaries are well studied and modeled, sediment and contaminants often originate from the margin regions, and the margins remain poorly characterized. We conducted a 24 hour field experiment in a channel slough of South San Francisco Bay, and measured settling velocity, turbulence and flow, and suspended sediment concentration. At this margin location, we found average settling velocities of 4-5*10-5 m/s, and saw settling velocities decrease with decreasing suspended sediment concentration. These results are consistent with, though at the low end of, those seen along the estuary center, and they suggest that the two population model that has been successful along the shoals may also apply in the margins.

  5. Oil spill response planning on the Columbia river estuary

    International Nuclear Information System (INIS)

    The Columbia River Estuary lies along the Washington-Oregon state boundary on the west coast of the United States. The entire area is environmentally very sensitive with numerous large, shallow bays, exposed mud flats, wetland areas, and central channels having maximum currents of three to four knots. These features make the area very difficult to protect from an oil spill. Spill response is further complicated because of the many different state, federal, and local jurisdictions with mandated responsibilities in oil spill response and environmental protection. Under the leadership of the US Coast Guard Marine Safety Office in Portland, Oregon, a steering group was established to guide the development of a response plan for the Columbia River Estuary. A concerted effort was made to include representatives from response organizations, natural resource agencies, and resource users from federal, state, and local governments, and commercial sectors in the planning process. The first draft of an operational response plan was completed the summer of 1992 through a combination of technical workshops, field trips, and small working groups meeting with local communities. The Columbia River Estuary Response Plan prioritizes areas to protect; identifies specific response strategies for protecting these areas; and outlines the Iogistics needed to implement these strategies, including equipment needs, the location of staging areas, and the identification of pre-designed command posts. The local spill response cooperative and oil transportation industry are using the plan to coordinate the purchase of response equipment and the staging of this equipment at numerous locations along the river. The key to success is ensuring that all the groups responding to an event participate in the planning process together. This process has worked well and will serve as a model for response planning for other areas along the Columbia River and coastal areas of Washington and Oregon

  6. An Experimental Study on Major Element Release from the Sediments in the Changjiang (Yangtze River) Estuary

    Institute of Scientific and Technical Information of China (English)

    GUO Yanwei; YANG Shouye

    2015-01-01

    With the enhanced warming and acidification of global ocean, whether and to what extent the naturally-weathered fluvial sediment into the sea can release elements and thus influence the geochemical process and ecosystem of global ocean remain to be resolved. In this contribution, an experimental study was carried out to examine the release rates of major elements (Ca, K, Mg and Al) from the surface sediments in the Changjiang (Yangtze River) Estuary under the pH values of 4.0, 6.0 and 7.0. The two studied sediments consist primarily of quartz, plagioclase, calcite and clay minerals, with the BET (Brunauer, Emmett and Teller) surface areas of 61.7m2g-1 and 23.1m2g-1. Major elements of Ca, K, Mg and Al show different release rates under different solution pH values. With the decreasing solution pH, the release rates of Ca and K increase obviously, while the release rates of Mg and Al increase with the initial solution pH varying from 6.0 to 7.0. The different release rates of these elements are closely related to the original mineral composition of the sediments and the reaction kinetics. Based on the experimental observation, quartz and clay minerals that have low dissolution rates may dominate the major element release to the aqueous phase. This study reveals that the en-hancing ocean acidification could cause considerable release of major elements from natural terrigenous sediments into the ambient marine environment, which has to be considered carefully in the future study on global change.

  7. Influence of habitat structure and mouth dynamics on avifauna of intermittently-open estuaries: A study of four small South African estuaries

    Science.gov (United States)

    Terörde, Anja I.; Turpie, Jane K.

    2013-07-01

    Habitat composition was a major factor in determining waterbird species composition and abundance, particularly the area of floodplain and vegetated channel in four intermittently open estuaries (IOEs) in the warm-temperate coastal biogeographical region of South Africa. Average bird densities on the four estuaries varied from 0.5 to 4.2 birds per hectare, and community composition differed significantly between estuaries. However, the considerable variation in abundance of macrophytes did not have a detectable effect on waterbirds. Under closed mouth conditions, piscivorous birds dominated the avifauna. Each estuary's avifauna responded differently in terms of changes in feeding guild composition when the mouth opened. Bird abundance changed immediately after breaching, but not consistently. Diversity was significantly higher under open-mouth conditions for three of the four estuaries, and species composition was significantly different from that under closed-mouth conditions at all four estuaries. Changes in mouth dynamics as a result of climate change, water abstraction and artificial breaching could lead to significant changes in estuarine fauna.

  8. Turbine airfoil with ambient cooling system

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, Jr, Christian X.; Marra, John J.; Marsh, Jan H.

    2016-06-07

    A turbine airfoil usable in a turbine engine and having at least one ambient air cooling system is disclosed. At least a portion of the cooling system may include one or more cooling channels configured to receive ambient air at about atmospheric pressure. The ambient air cooling system may have a tip static pressure to ambient pressure ratio of at least 0.5, and in at least one embodiment, may include a tip static pressure to ambient pressure ratio of between about 0.5 and about 3.0. The cooling system may also be configured such that an under root slot chamber in the root is large to minimize supply air velocity. One or more cooling channels of the ambient air cooling system may terminate at an outlet at the tip such that the outlet is aligned with inner surfaces forming the at least one cooling channel in the airfoil to facilitate high mass flow.

  9. Evolución de la sociabilidad en Hymenoptera: Rasgos conductuales vinculados a niveles sociales y precursores de sociabilidad en especies solitarias Evolution of sociality in Hymenoptera: Behavioural traits linked to social levels and precursors of sociality in solitary species

    Directory of Open Access Journals (Sweden)

    LUIS FLORES-PRADO

    2012-09-01

    Full Text Available En Hymenoptera, los niveles de sociabilidad han sido asociados a rasgos conductuales, tales como los comportamientos de nidificación y agonísticos, y la capacidad de reconocimiento entre conespecíficos. El reconocimiento de compañeros de nido es un fenómeno de amplia difusión entre especies eusociales, y puede ser inferido por el resultado de las interacciones agonísticas entre hembras; estas son más tolerantes hacia compañeras de nido que hacia no compañeras de nido. Contrariamente, en la mayor parte de las especies solitarias las hembras son agresivas hacia otras hembras conespecíficas. En especies eusociales, la descendencia inmadura es alimentada directamente por la madre, o por obreras; así, el contacto frecuente entre progenie y hembras adultas puede contribuir a entender el reconocimiento social. En el extremo opuesto, las especies solitarias construyen nidos que no permiten interacciones entre adultos e inmaduros. A pesar de esto, estudios recientes sugieren que el aprendizaje del fenotipo propio podría explicar la capacidad de reconocimiento y, tal vez, corresponde al punto de partida en el desarrollo y evolución de la sociabilidad. La subfamilia Xylocopinae (Apidae ha emergido como un valioso modelo para estudiar la evolución de la sociabilidad pues contiene especies que presentan un amplio rango de sociabilidad. En particular, la tribu Manueliini representa un taxón interesante desde el punto de vista de la evolución de la sociabilidad en Xylocopinae pues ha sido propuesto como el grupo hermano de todos los demás Xylocopinae, es un taxón relicto que retiene rasgos morfológicos ancestrales, contiene solo especies fundamentalmente solitarias (aunque en una de estas se ha demostrado recientemente reconocimiento de compañeras de nido y de parientes y algunas especies exhiben rasgos conductuales precursores de vida social. En este trabajo se revisa en Hymenoptera los grados de sociabilidad asociados con rasgos

  10. Nutrient transport to the Swan-Canning Estuary, Western Australia

    Science.gov (United States)

    Peters, Norman E.; Donohue, Robert

    2001-09-01

    Catchment nutrient availability in Western Australia is primarily controlled by the disposal of animal waste and the type and rate of fertilizer application, particularly on the relatively narrow (25 km wide), sandy coastal plain. Nitrogen (N) and phosphorus (P) concentrations and fluxes during the wet season of 15 tributaries, including four urban drains to the Swan-Canning Estuary, were evaluated from 1986 to 1992 and additionally concentrations only were evaluated throughout the year from 1993 to 1996. Concentrations of filtered reactive P (FRP) and total P (TP) were generally low, with the volume-weighted means for all sites being 0·06 mg l-1 and 0·12 mg l-1 respectively. The urban drains had higher TP concentrations (volume-weighted mean of 0·21 mg l-1) than the streams (0·12 mg l-1), with the high concentrations associated with particulate matter. Total inorganic N (TIN, NH4N plus NO3N) and total N (TN), which is of interest to eutrophic status of the N-limited estuary, were likewise low, compared with other developed areas having a similar climate. Both TIN and TN were higher in the urban drains (0·76 mg l-1 and 1·5 mg l-1 respectively) than the streams (0·31 mg l-1 and 1·2 mg l-1 respectively). The Avon River, which drains 98·5% of the 121 000 km2 catchment area, contributes most of the N (0·03 kg ha-1 year-1 or 65%) and a high percentage of the P (superphosphate and has the highest FRP (0·51 mg lestuary. The coastal plain is also undergoing urbanization, particularly in areas adjacent to the estuary. Nutrients are subsequently available for transport during the onset of seasonal wet weather. Perennial baseflow from urban areas is an important source of nutrients. Water yield from the urban areas was high, being as much as 50% of annual rainfall. The timing of the nutrients delivered by the tributaries may be an important control on estuarine ecology

  11. The Mattole River Estuary: Restoration Efforts in a Dynamic System

    Science.gov (United States)

    Barber, D.; Liquori, M.

    2010-12-01

    Despite extensive scientific advancement integrating our understanding of hydrology, geomorphology, and ecology in recent decades, the application of restoration in the field has been slow to evolve. This presentation will highlight 20 years of restoration practices in the Mattole River Estuary and how these practices have informed our understanding of this complex system. The Mattole River Watershed is a 304 square-mile basin located near the Mendocino Triple Junction in a remote region of California known as the “The Lost Coast” for its rugged mountains and undeveloped coastline. In addition to numerous species of fish, mammals, and over 250 bird species, the Mattole Watershed is home to three Federally-listed Threatened salmonids: California Coastal Chinook salmon, Southern Oregon/Northern California Coasts coho salmon, and Northern California steelhead trout. The 64 mile-long river meets the Pacific Ocean at the northern end of the 64,000 acre King Range National Conservation Area (KRNCA), managed by the Bureau of Land Management (BLM). The watershed is dynamic, with some of the nation’s highest annual rainfall (mean = 158 cm/yr), naturally occurring steep slopes, erosive sedimentary geology, and frequent earthquakes. All of these factors have amplified the negative effects of extensive logging and associated road building between 1945 and 1970, which left a legacy of increased sediment loads and high water temperatures that have yet to recover to pre-disturbance levels, severely impairing riparian and aquatic habitats. Prior to major land disturbances, the Mattole estuary/lagoon was notable for its deep, thermally-stratified pools and numerous functioning north and south bank slough channels that flushed sediments from the river and received marine water. As flows decline in late spring, a sandbar closes off surface flow from the river to the Pacific Ocean, forming a lagoon, which persists until flows increase in the fall. Today, the estuary is poor

  12. The Salt fluxes in a tidally-energetic estuary

    OpenAIRE

    Simpson, J H; Vennell, R.; A. J. Souza

    2001-01-01

    Time series measurements of velocity and salinity have been used to examine the salt flux components in the tidally-energetic regime of the Conwy Estuary in North Wales. The instantaneous volume transport, up to 400 m3 s−1, was deduced from a current meter located in mid-channel using a frictional model with a correction for the observed mean velocity shear. Transport estimates obtained in this way have been compared with independent measurements of integrated cross-section transport using a ...

  13. Hydrodynamics and Water Quality: Modeling Rivers, Lakes, and Estuaries

    Science.gov (United States)

    Opdyke, Daniel

    2008-09-01

    The modeling of lakes, rivers, and estuaries is a fascinating subject that combines interesting facets of mathematics, statistics, physics, chemistry, and biology. Because of the complexity of natural systems, such modeling is always an approximation of the real world-and sometimes not a very good one. It is for this reason that modeling is not just science but also art. It is also for this reason that there are few good texts offering practical advice on modeling. Hydrodynamics and Water Quality makes a valiant attempt but is only partially successful because of the book's narrow focus on one family of models and an inconsistent presentation.

  14. The herbicide Glyphosate affects nitrification in the Elbe estuary, Germany

    Science.gov (United States)

    Sanders, Tina; Lassen, Stephan

    2015-04-01

    The Elbe River is one of the biggest European rivers discharging into the North Sea. It also transports high amounts of nutrients and pollutants like pesticides. Important source regions of both nutrients and pollutants are located within the river catchment, which is dominated by agricultural land-use. From these agricultural soils, pesticides can be carried via the river and estuary into the North Sea. Glyphosate (N-(phosphonomethyl) glycine) is the most commonly used herbicide worldwide and mainly used to regulate unwanted plant growth and for the expedition of crop ripening. In Germany, ~ 6000 tons of glyphosate are applied yearly in agriculture and private use. Glyphosate is degradable by microorganisms and has a half-life in water of 35 to 60 days. This herbicide specifically inhibits 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), an enzyme that catalyzes the biosynthesis of essential aromatic amino acids in plants, fungi, and bacteria. Nitrifying bacteria, which play an important role in the internal nitrogen cycling in the Elbe estuary, also possess this enzyme. The aim of our study was to quantify the concentration of glyphosate in water and sediment samples of the Elbe to get an overview about relevant environmental levels and to assess the impact of glyphosate on inhibition of nitrifying activities. To quantify the effect of glyphosate on nitrification activity, natural samples as well as pure cultures of Nitrosomonas europea (strain Nm50) were incubated with different concentrations of glyphosate over a period of some weeks. The nitrifying activity was determined according to changes of the nitrite and nitrate concentration as well as the cell number. Glyphosate was detectable in water and sediment samples in the Elbe estuary with up to 5 ppb mainly in the Port of Hamburg region. In both incubation experiments an inhibiting effect of glyphosate on nitrification could be shown. The incubated natural water sample was affected by a glyphosate

  15. Det ambientes fænomenologi

    DEFF Research Database (Denmark)

    Walther-Hansen, Mads

    2014-01-01

    Det ambiente: sansning, medialisering, omgivelse er et aktuelt og ambitiøst værk. Bogen skildrer hvordan ambiente fænomener har fået en stigende betydning i den moderne verden, og redegør for måden hvorpå det ambiente virker ind på hele vores oplevelseskultur. Det er en levende, uprætentiøs og fr...

  16. Predicateμ-Calculus for Mobile Ambients

    Institute of Scientific and Technical Information of China (English)

    Hui-Min Lin

    2005-01-01

    Ambient logics have been proposed to describe properties for mobile agents which may evolve over time as well as space. This paper takes a predicate-based approach to extending an ambient logic with recursion, yielding a predicate t-calculus in which fixpoint formulas are formed using predicate variables. An algorithm is developed for model checking finite-control mobile ambients against formulas of the logic, providing the first decidability result for model checking a spatial logic with recursion.

  17. Ambient air pollution and the fetus

    OpenAIRE

    Kadriye Yurdakök

    2013-01-01

    There is a growing evidence on the hazards of ambient air pollution on fetal development. Several review articles have been published on the adverse fetal outcomes including low birth weight, preterm birth, small-for-gestational age, and congenital anomalies. Recent studies have linked ambient air pollution to gestational hypertension, and preeclampsia which may be related to the detrimental effect of ambient air pollution on placental growth and function. Short-term and long-term exposure to...

  18. Ambient noise near the sea-route

    Institute of Scientific and Technical Information of China (English)

    HE Li; LI ZhengLin; PENG ZhaoHui

    2009-01-01

    Ambient noise data measured in an experiment conducted in shallow water near a sea-route were analyzed. It was observed that, at low frequency, the horizontal correlation has an obvious difference from that predicted by the classical ambient noise model. The theoretical analyses show that this phenomenon is caused by wind noise together with the discrete shipping noise nearby. An ambient noise model was proposed to include the effects caused by both the noise sources. Data measured at different times verify that the proposed model can be used to forecast the ambient noise field in shal-low water near the sea-route.

  19. Ambient noise near the sea-route

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Ambient noise data measured in an experiment conducted in shallow water near a sea-route were analyzed. It was observed that, at low frequency, the horizontal correlation has an obvious difference from that predicted by the classical ambient noise model. The theoretical analyses show that this phenomenon is caused by wind noise together with the discrete shipping noise nearby. An ambient noise model was proposed to include the effects caused by both the noise sources. Data measured at different times verify that the proposed model can be used to forecast the ambient noise field in shallow water near the sea-route.

  20. Development of an estuarine assessment scheme for the management of a highly urbanised catchment/estuary system, Sydney estuary, Australia.

    Science.gov (United States)

    Birch, G F; Gunns, T J; Chapman, D; Harrison, D

    2016-05-01

    As coastal populations increase, considerable pressures are exerted on estuarine environments. Recently, there has been a trend towards the development and use of estuarine assessment schemes as a decision support tool in the management of these environments. These schemes offer a method by which complex environmental data is converted into a readily understandable and communicable format for informed decision making and effective distribution of limited management resources. Reliability and effectiveness of these schemes are often limited due to a complex assessment framework, poor data management and use of ineffective environmental indicators. The current scheme aims to improve reliability in the reporting of estuarine condition by including a concise assessment framework, employing high-value indicators and, in a unique approach, employing fuzzy logic in indicator evaluation. Using Sydney estuary as a case study, each of the 15 sub-catchment/sub-estuary systems were assessed using the current scheme. Results identified that poor sediment quality was a significant issue in Blackwattle/Rozelle Bay, Iron Cove and Hen and Chicken Bay while poor water quality was of particular concern in Duck River, Homebush Bay and the Parramatta River. Overall results of the assessment scheme were used to prioritise the management of each sub-catchment/sub-estuary assessed with Blackwattle/Rozelle Bay, Homebush Bay, Iron Cove and Duck River considered to be in need of a high priority management response. A report card format, using letter grades, was employed to convey the results of the assessment in a readily understood manner to estuarine managers and members of the public. Letter grades also provide benchmarking and performance monitoring ability, allowing estuarine managers to set improvement targets and assesses the effectiveness of management strategies. The current assessment scheme provides an effective, integrated and consistent assessment of estuarine health and

  1. Residual fluxes of water and nutrient transport through the main inlet of a tropical estuary, Cochin estuary, West Coast, India.

    Science.gov (United States)

    Vinita, J; Lallu, K R; Revichandran, C; Muraleedharan, K R; Jineesh, V K; Shivaprasad, A

    2015-11-01

    Determining robust values for estuarine material fluxes has been a complex task and an interdisciplinary research challenge. With the advent of acoustic Doppler profilers (ADPs) having bottom-track capability and which provides three-dimensional current velocity profiles, more accurate estimation of cross-sectional fluxes is far accomplished in unsteady and bidirectional flow conditions of estuaries. This paper reports for the first time the discharge measurements conducted across Cochin inlet using ADP to examine the spring-neap variability in residual fluxes of water and nutrients during dry season. Cross-sectional current velocity profiles and salinity profiles were captured using ADP and conductivity temperature depth (CTD) instrumentation. Samples of surface and bottom water were also collected at 3-h intervals. The results indicated that there is a distinct transition from the neap to spring tides related to flow and salinity structure. The neap tide was partially mixed with large diurnal inequalities whereas the spring tide was well-mixed with symmetric tides. During ebb, an increase in the concentrations of nitrate, nitrite, phosphate, and silicate was noticed indicating upstream sources for their inputs. In contrast, elevated levels of ammonia were found in the estuary throughout the period of observation. There was net residual outflow during both tides, and the computed residual water fluxes of neap doubled that of spring. The strong ebb currents and the increased nutrient concentrations during ebb resulted in the export of all nutrients (except ammonia during spring) into the sea. The findings of this study highlight the consequences of anthropogenic interventions in the estuary and their effects on the fluxes of ecologically relevant substances. PMID:26446129

  2. Sedimentology and ichnology of the fluvial reach to inner estuary of the Ogeechee River estuary, Georgia, USA

    Science.gov (United States)

    Shchepetkina, Alina; Gingras, Murray K.; Pemberton, S. George

    2016-08-01

    Through the integration of sedimentological and ichnological observations, this paper explores the character of sediments deposited across the fluvio-tidal transition zone of the upper microtidal, mixed-energy, sand-dominated Ogeechee River estuary, Georgia, USA. A transect of tidally influenced to fluvial channel-bars and their facies variability is reported. Field and laboratory methods were employed, including observation of physical and biogenic sedimentary structures on the point-bar surfaces and in trenches, collection of grab samples, suction and box coring, grain size and total organic carbon analyses, optical microscopy, core logging, and daylight photography. The data presented in the paper can help in predicting facies changes across the fluvio-tidal transition of sand-dominated fluvio-tidal deposits in the rock record. The lower inner estuary is characterized by medium-fine and fine-medium sand with planar and trough cross-bedding, small-scale ripple lamination, tidal sedimentary structures (flaser and wavy bedding, herringbone cross-stratification), abundant organic debris, and mud rip-up clasts. Bioturbation of the intertidal point bars is low, but cryptobioturbation is locally observed. Upper inner estuary deposits comprise coarse-medium- and medium-coarse-grained sand, and are characterized by faint high-angle planar and trough cross-bedding. Organic debris, mud rip-up clasts, herringbone and current-ripple lamination are rarely observed. Bioturbation is absent to sparse. The fluvio-tidal transition is represented by very-coarse- to coarse-grained sand and granules. Physical sedimentary structures constitute massive, graded planar and trough cross-bedding with abundant plant detritus. Except for rare Siphonichnus- and Lockeia-like traces, bioturbation is absent. The fluvial setting is characterized by coarse-medium sand with unidirectional cross-bedding, current-ripple lamination, and rare organic-rich mud clasts. Bioturbation is absent. Inner

  3. The carbohydrates in relation to mineralogic and granulometric composition of surface sediments in the karst estuary (River Krka estuary, Yugoslavia)

    Science.gov (United States)

    Hadz̆ija, Olga; Jurac̆ić, Mladen; Luić, Marija; Tonković, Maja; Jeric̆ević, Biserka

    1985-11-01

    The investigation of mineral, granulometric and chemical composition of sediments of the River Krka estuary (Yugoslavia) were performed in order to elucidate the origin of the sediments and the pattern of sedimentation. Estuarine surface sediments were found to be fine-grained with a bimodal distribution. Environmental conditions in estuarine sediments favour conservation of the organic matter (anoxic conditions). The carbohydrates in the sediments were investigated to determine whether they are of terrigenous or authigenous origin. Glucose, galactose, mannose, xylose, rhamnose, glucosamine and glucuronic acid were detected in the sediments. Their mutual relationship indicates a preferentially terrigenous source of sedimented organic material in estuarine sediments.

  4. Identificación de rasgos morfológicos para una rápida diferenciación de sardina austral (Sprattus fuegensis y sardina común (Strangomera bentincki

    Directory of Open Access Journals (Sweden)

    Antonio Aranis

    2014-11-01

    Full Text Available La pesquería artesanal de cerco multiespecífica que opera en aguas interiores de Chiloé captura sardina común (Strangomera bentincki y sardina austral (Sprattus fuegensis al mismo tiempo y en la misma área. Debido a la gran similitud morfológica externa que presentan estas dos especies de peces óseos, la identificación específica en terreno es difícil, aún para observadores científicos experimentados. Por lo tanto, el objetivo de este trabajo es proponer cual o cuales rasgos morfométricos externos debiesen ser considerados para una rápida identificación de estas especies en terreno. Se analizaron 60 ejemplares de sardina común y 79 de sardina austral. Se identificaron los ejemplares a nivel de especie y se registraron las siguientes medidas: longitud total, longitud de la cabeza, preórbita, órbita y posórbita. Todas las medidas morfométricas fueron estandarizadas para evitar colinealidad. Las diferencias en las medidas morfométricas entre especies fueron probadas mediante métodos estadísticos multivariados que incluyen el análisis de componentes principales, análisis de varianza y covarianza (ANOVA y ANCOVA, análisis multivariado de covarianza (MANOVA y análisis lineal discriminante. La medida posórbita fue el rasgo morfométrico que presentó mayor diferenciación entre especies. Se concluye que la medida de posórbita es por sí sola un carácter morfométrico externo que permitiría una rápida identificación de estas especies en terreno. Los resultados de esta investigación pueden ser tomados como línea base para la generación de guías de campo que apoyen el trabajo de identificación de especies de los observadores científicos.

  5. Oxygen depletion off the Changjiang (Yangtze River)Estuary

    Institute of Scientific and Technical Information of China (English)

    LI; Daoji; (李道季); ZHANG; Jing; (张经); HUANG; Daji; (黄大吉); WU; Ying; (吴莹); LIANG; Jun; (梁俊)

    2002-01-01

    In a survey on the Yellow Sea and the East China Sea on August 20-30 of 1999, we found a hypoxic zone (<2 mg/L) of 13700 km2 with an average thickness of 20m at the bottom of the Changjiang (Yangtze River) Estuary, with an oxygen minimum value of 1 mg/L. The extension of the dissolved oxygen deficiency extended to the 100m isobath in a southeastward direction along the bottom of the continental shelf of the East China Sea. During the last two decades, the minimum dissolved oxygen values in the low oxygen region of the Changjiang Estuary have decreased from 2.85 mg/L to 1 mg/L. In the hypoxic zone, the apparent oxygen utilization (AOU) was 5.8 mg/L and the total oxygen depletion approximately 1.59×106 t. The strong halocline above the hypoxic zone, as a result of affluent water from the Changjiang, Taiwan Warm Current (TWC), and the high concentrations of particle organic carbon (POC) and nitrogen (PON) are the major factors causing the formation of the hypoxic zone. The POC: PON ratios and nutrient concentration distributions in the hypoxic zone suggest that the oxygen deficiency in the bottom water during the summer in the East China Sea off the Changjiang is the result of organic carbon production enhanced by nutrients from the Changjiang and fluvial organic matter input, followed by a shift in regeneration of nutrients in the East China Sea.

  6. Modeling Residual Circulation and Stratification in Oujiang River Estuary

    Institute of Scientific and Technical Information of China (English)

    LIN Wei-bo; WANG Yi-gang; RUAN Xiao-hong; XU Qun

    2012-01-01

    A 3D,time-dependent,baroclinic,hydrodynamic and salinity model was implemented and applied to the Oujiang River estuarine system in the East China Sea.The model was driven by the forcing of tidal elevations along the open boundaries and freshwater inflows from the Oujiang River.The bottom friction coefficient and vertical eddy viscosity were adjusted to complete model calibration and verification in simulations.It is demonstrated that the model is capable of reproducing observed temporal variability in the water surface elevation and longitudinal velocity,presenting skill coefficient higher than 0.82.This model was then used to investigate the influence of freshwater discharge on residual current and salinity intrusion under different freshwater inflow conditions in the Oujiang River estuary.The model results reveal that the river channel presents a two-layer structure with flood currents near the bottom and ebb currents at the top layer in the region of seawater influenced on north shore under high river flow condition.The river discharge is a major factor affecting the salinity stratification in the estuarine system.The water exchange is mainly driven by the tidal forcing at the estuary mouth,except under high river flow conditions when the freshwater extends its influence from the river's head to its mouth.

  7. The occurrence of selected human pharmaceutical compounds in UK estuaries.

    Science.gov (United States)

    Thomas, Kevin V; Hilton, Martin J

    2004-09-01

    This report describes a scoping study conducted in order to establish whether pharmaceutical compounds may be present in UK estuaries. Surface water samples collected from five UK estuaries were analysed for the presence of 14 pharmaceutical compounds selected from the priority lists of the UK Environment Agency and the Oslo and Paris Commission (OSPAR). The pharmaceutical compounds/metabolites clofibric acid, clotrimazole, dextropropoxyphene, diclofenac, ibuprofen, mefenamic acid, propranolol, tamoxifen and trimethoprim were detected at measurable concentrations in the samples collected. The concentrations of erythromycin, lofepramine, paracetamol, sulfamethoxazole and acetyl-sulfamethoxazole were all below the limits of detection of the methods used (between 4 and 20 ng l(-1)). The anti-fungal agent clotrimazole was the most frequently detected at a maximal concentration of 22 ng l(-1) and a median concentration of 7 ng l(-1). The analgesic compound ibuprofen was detected at a maximal concentration of approximately 930 ng l(-1) and a median concentration of 48 ng l(-1), whilst the other pharmaceutical compounds were detected between the limits of detection of the method used and 570 ng l(-1). PMID:15325211

  8. Mathematical simulation of sediment and radionuclide transport in estuaries

    International Nuclear Information System (INIS)

    The finite element model LFESCOT (Flow, Energy, Salinity, Sediment and Contaminant Transport Model) was synthesized under this study to simulate radionuclide transport in estuaries to obtain accurate radionuclide distributions which are affected by these factors: time variance, three-dimensional flow, temperature, salinity, and sediments. Because sediment transport and radionuclide adsorption/desorption depend strongly on sizes or types of sediments, FLESCOT simulates sediment and a sediment-sorbed radionuclide for the total of three sediment-size fractions (or sediment types) of both cohesive and noncohesive sediments. It also calculates changes of estuarine bed conditions, including bed elevation changes due to sediment erosion/deposition, and three-dimensional distributions of three bed sediment sizes and sediment-sorbed radionuclides within the bed. Although the model was synthesized for radionuclide transport, it is general enough to also handle other contaminants such as heavy metals, pesticides, or toxic chemicals. The model was checked for its capability for flow, water surface elevation change, salinity, sediment and radionuclide transport under various simple conditions first, confirming the general validity of the model's computational schemes. These tests also revealed that FLESCOT can use large aspect ratios of computational cells, which are necessary in handling long estuarine study areas. After these simple tests, FLESCOT was applied to the Hudson River estuary between Chelsea and the mouth of the river to examine how well the model can predict radionuclide transport through simulating tidally influenced three-dimensional flow, salinity, sediment and radionuclide movements with their interactions

  9. Trophic interactions of Platichthys flesus and Solea solea juveniles in the Lima estuary nursery (NW Portugal

    Directory of Open Access Journals (Sweden)

    Cláudia Mendes

    2015-12-01

    Full Text Available Trophic interactions play a key role in nursery habitats, and by affecting growth and condition of the juveniles, may control the quality of a given estuarine nursery. This study investigated the trophic ecology of flounder (Platichthys flesus and common sole (Solea solea juveniles in the Lima estuary nursery. Feeding location, main organic matter sources, and prey of the target species were assessed by carbon (δ13C and nitrogen (δ15N stable isotopes, as well as by stomach content analysis. The juveniles, macroinvertebrates, and sediment and water column samples were collected in August 2014 in the lower, middle and upper sections of the Lima estuary. The diet of 0+ flounder relied upon prey from the upper estuary (salinity >5, namely Chironomid larvae and Corophium spp. which showed the role of the upper estuary prey to the 0+ flounder diet and suggest the relative site fidelity of the young juveniles. In contrast, 1+ flounder juveniles had a diverse diet based on bivalves, polychaetes and crustaceans, and a variable stable isotope signature indicating they fed in different areas along the estuary. The 1+ sole juveniles also fed on polychaetes, crustaceans, and bivalves, but the stable isotope values suggested a dependence on the lower estuary (salinity >30 and marine food web sources. Such differential use of food may be understood as a strategic approach to reduce intra- and interspecific competition and thus ensuring the use of Lima estuary as nursery area for these two flatfish species.

  10. Numerical Model of Pollution Dispersion in the Gour Soozan Estuary – Bandar Abbas, Iran

    Directory of Open Access Journals (Sweden)

    Arefe Emami

    2013-01-01

    Full Text Available Pollution and the dispersion of pollutants are important issues in the environment of rivers and estuaries, being regarded as the major problems in utilizing the surface water globally. Environmentally speaking, the Gour Soozan Estuary suffers from a lot of problems. Arriving at a model for the dispersion of pollution and pollutant particles will therefore provide useful information for future studies in the field of environment and developmental activities in Bandar Abbas. Taking the available field data into account and using Delf3D numerical models, the present study has firstly contended with the hydrodynamic modeling of the estuary; and regarding the obtained hydrodynamic conditions, it has then conducted a two-dimensional modeling of pollution dispersion in the region. The results show that the dispersion of pollution in the cross-sectional area of the estuary has had a rising trend whose concentration gradient does not decline over time. With water flows advancing from the mouth of the estuary toward its end, the dispersion and transfer of pollutant particles will decrease due to the reduction in the range of tidal fluctuations. With releasing pollutant particles in the estuary momentarily, they will gradually leave the estuary through an oscillatory motion over time, being transported to the west of the Persian Gulf and endangering the environment in the west coasts of Bandar Abbas.

  11. A numerical study of local variations in tidal regime of Tagus estuary, Portugal.

    Directory of Open Access Journals (Sweden)

    João Miguel Dias

    Full Text Available Tidal dynamics of shallow estuaries and lagoons is a complex matter that has attracted the attention of a large number of researchers over the last few decades. The main purpose of the present work is to study the intricate tidal dynamics of the Tagus estuary, which states as the largest estuary of the Iberian Peninsula and one of the most important wetlands in Portugal and Europe. Tagus has large areas of low depth and a remarkable geomorphology, both determining the complex propagation of tidal waves along the estuary of unknown manner. A non-linear two-dimensional vertically integrated hydrodynamic model was considered to be adequate to simulate its hydrodynamics and an application developed from the SIMSYS2D model was applied to study the tidal propagation along the estuary. The implementation and calibration of this model revealed its accuracy to predict tidal properties along the entire system. Several model runs enabled the analysis of the local variations in tidal dynamics, through the interpretation of amplitude and phase patterns of the main tidal constituents, tidal asymmetry, tidal ellipses, form factor and tidal dissipation. Results show that Tagus estuary tidal dynamics is extremely dependent on an estuarine resonance mode for the semi-diurnal constituents that induce important tidal characteristics. Besides, the estuarine coastline features and topography determines the changes in tidal propagation along the estuary, which therefore result essentially from a balance between convergence/divergence and friction and advection effects, besides the resonance effects.

  12. Understanding the fate of iron in a modern temperate estuary: Leirarvogur, Iceland

    International Nuclear Information System (INIS)

    Highlights: → Fluvial Fe (aq) and Fe (total) concentrations drop upon mixing with seawater in estuaries. → The majority of Fe in estuaries is lost in the bay-head delta. → Our results suggest that the bay-head delta is a key location in Fe-mineral formation. → Isotopic variation in estuarine waters may play a role in the formation of Fe-minerals. - Abstract: Fluvial dissolved Fe concentrations decrease upon mixing with seawater, resulting in the formation of Fe-floccules. However, a clear understanding of the fate of these floccules has yet to be established. Assessing how tidal processes affect the formation of Fe-colloids in the Leirarvogur estuary, SW Iceland, is an important step in understanding the formation and potential deposition of estuarine Fe-rich minerals within this estuarine system. The Leirarvogur estuary drains predominately Fe-rich basalt, increasing the likelihood of detecting changes in Fe-phases. Fluvial waters and local lake waters that drain into the estuary were compared and the effects of seasonal changes were considered, in an attempt to understand how varying end-members and external factors play a role in Fe-rich mineral formation. Aqueous and colloidal Fe concentrations were found to be greater towards the head of the Leirarvogur estuary, suggesting that potential Fe-rich minerals and complexes are forming at sites of fluvial input. Increasing suspended colloidal Fe towards the estuary mouth suggests that Fe-colloids are readily transported seaward.

  13. Trace elements and radionuclides in the Connecticut River and Amazon River estuary

    International Nuclear Information System (INIS)

    The Connecticut River, its estuary, and the Amazon River estuary were studied to elucidate some of the processes which control river water chemistry and the flux of elements to the sea. The approach taken was to identify inputs to the Connecticut River and to investigate geochemical processes which modify the dissolved load. The form and quantity of nuclides which are in turn supplied to the estuary are altered by processes unique to that transition zone to the ocean. The Connecticut River estuary was sampled on a seasonal basis to investigate the role of the estuary in controlling the flux of elements to the sea. The knowledge gained from the Connecticut River study was applied to the quantitatively more significant Amazon River estuary. There a variety of samples were analyzed to understand the processes controlling the single greatest flux of elements to the Atlantic Ocean. The results indicate that estimates of the total flux of nuclides to the oceans can best be calculated based on groundwater inputs. Unless significant repositories for nuclides exist in the river-estuarine system, the groundwater flux of dissolved nuclides is that which will eventually be delivered to the ocean despite the reactions which were shown to occur in both rivers and estuaries. 153 references, 63 figures, 28 tables

  14. Accumulation of Phosphorus and Heavy Metals in the Swan-Canning Estuary, Western Australia

    Science.gov (United States)

    Gerritse, R. G.; Wallbrink, P. J.; Murray, A. S.

    1998-08-01

    Accumulation rates of P and of Zn, Cd, Pb and Cu were measured in sediment cores from the Swan-Canning Estuary in Western Australia. The main sources of P in sediments are catchments of the major tributaries Ellen Brook and Avon River. Since 1940, anthropogenic P has increased about five times in sediments of Ellen Brook and has almost trebled in sediments of the estuary. Records show that since 1940 dissolved inorganic P in the estuary has increased between two and three times. Though dissolved inorganic P appears to be conservatively mixed in the estuary, sediment inventories suggest that a significant part of the input of P is retained in the estuary. A combination of high concentrations of dissolved P in Ellen Brook and large fluxes of particulate matter from the Avon River could explain this. Concentrations of Zn, Cd, Pb and Cu in sediments have risen significantly since colonial settlement and, unlike P concentrations, have been dominated by inputs from sources near the estuary. Vertical distributions of metals in sediment cores from the estuary suggest that, historically, concentrations of Zn and Cd started increasing first, followed by Cu and then P and Pb.Acid extractable Pb, unlike Zn, Cd and Cu, in surface sediments is greater than expected from equilibration with the water column. This is attributed to the presence of particulate Pb-oxides from road runoff.

  15. Estimation of total suspended matter in the Zhujiang (Pearl)River estuary from Hyperion imagery

    Institute of Scientific and Technical Information of China (English)

    LIU Dazhao; FU Dongyang; XU Bing; SHEN Chunyan

    2012-01-01

    Although remote sensing data have been used to estimate total suspended matter (TSM) in coastal waters,it has limitations when applied to estuary waters in low spatial resolution situations.The spatial resolution of ocean color satellites such as SeaWiFS and MODIS is usually ~1 km,and therefore is not adequate for small,local-scale areas such as the Zhujiang (Pearl) River estuary.In contrast,30 m-resolution EO-1 Hyperion imagery has potential for studying TSM in localized areas.We measured the surface spectral radiance reflectance of the river estuary water in the visible and near infra-red spectral range.Sensitivity analysis indicated that the ratio of remote sensing reflectance at 813 nm (Rrs(813)) to reflectance at 559 nm (Rrs(559)) could be used to estimate TSM concentration,and a linear relationship was established between the ratio and in-situ TSM concentration.We applied the linear relationship to Hyperion imagery to map TSM concentration in the estuary.The Hyperion imagery provided sufficient spatial resolution to detect spatiotemporal changes in TSM concentrations in the estuary small estuary area.This study demonstrated the usefulness of Hyperion imagery for mapping the distribution of TSM in estuary waters.

  16. Carbon budgets for two Portuguese estuaries: implications for the management and conservation of coastal waters

    Directory of Open Access Journals (Sweden)

    Ana P. Oliveira

    2014-07-01

    The results presented illustrate that Tagus and Sado estuaries represent an important land/ocean boundary for carbon transformation and emission, and confirm the anthropogenic pressure that these estuaries are subject to. Carbon budgets vary markedly within and between these two estuaries reflecting the human pressure. Anthropogenic inputs, autochthonous carbon production and primary production are indicated as the main responsible for the carbon production within the estuaries. Both estuaries export carbon to the ocean and to the atmosphere. The inorganic carbon faction has a major role in the carbon budget, enriching the ocean in carbon dioxide, contributing this for the greenhouse effect. Our understanding of organic and inorganic carbon fluxes in Tagus and Sado estuaries is vital for an efficient protection and preservation of such ecosystems being helpful in limit human-caused damage and in restoring damaged estuarine/coastal ecosystems. In addition, the economic impact of the carbon fluxes to the atmosphere, estimated as €375,000 per year, creates the appropriate incentives to reduce emissions and shift them to higher-value uses. Suggesting, therefore, a coastal management re-oriented towards a more adaptive approach through the use of carbon market-based policies. This study is a contribution to the integration of coastal and global carbon cycles. However, additional efforts are required to fully merge other components subsystems, such as salt marshes, with these budgets. Moreover, a fully comprehension of the community metabolism in these estuaries will greatly improve this integration.

  17. Assessment of heavy metals bioavailability and toxicity toward Vibrio fischeri in sediment of the Huelva estuary.

    Science.gov (United States)

    Rosado, Daniel; Usero, José; Morillo, José

    2016-06-01

    Relationship between toxicity and bioavailable metals in sediments from the Huelva estuary and its littoral of influence was analyzed. Toxicity was assessed with Microtox(®) bioassay using a marine luminescent bacterium: Vibrio fischeri. Bioavailable metals were considered as both, acid extractable fraction of BCR procedure and the sum of exchangeable and bound to carbonates fractions of Tessier sequential extraction. A bioavailable metals index was calculated to integrate results in a single figure. Toxicity and bioavailable metals showed a similar pattern. Higher levels were found in the estuary than in the littoral (140 TU/g). In Huelva estuary, highest levels were found in the Tinto estuary (5725 TU/g), followed by the Odiel estuary (5100 TU/g) and the Padre Santo Canal (2500 TU/g). Results in this area were well over than those in nearby estuaries. Furthermore, they are similar to or even higher than those in other polluted sediments around the world. Bioavailable metal index showed a stronger correlation with acid extractable fraction of BCR (R(2) = 0.704) than that for the sum of exchangeable and bound to carbonates fractions of Tessier (R(2) = 0.661). These results suggest that bioavailable metals are an important source of sediment toxicity in the Huelva estuary and its littoral of influence, an area with one of the highest mortality risks of Spain. PMID:27002282

  18. Pollutant Flux Estimation in an Estuary Comparison between Model and Field Measurements

    Directory of Open Access Journals (Sweden)

    Yen-Chang Chen

    2014-08-01

    Full Text Available This study proposes a framework for estimating pollutant flux in an estuary. An efficient method is applied to estimate the flux of pollutants in an estuary. A gauging station network in the Danshui River estuary is established to measure the data of water quality and discharge based on the efficient method. A boat mounted with an acoustic Doppler profiler (ADP traverses the river along a preselected path that is normal to the streamflow to measure the velocities, water depths and water quality for calculating pollutant flux. To know the characteristics of the estuary and to provide the basis for the pollutant flux estimation model, data of complete tidal cycles is collected. The discharge estimation model applies the maximum velocity and water level to estimate mean velocity and cross-sectional area, respectively. Thus, the pollutant flux of the estuary can be easily computed as the product of the mean velocity, cross-sectional area and pollutant concentration. The good agreement between the observed and estimated pollutant flux of the Danshui River estuary shows that the pollutant measured by the conventional and the efficient methods are not fundamentally different. The proposed method is cost-effective and reliable. It can be used to estimate pollutant flux in an estuary accurately and efficiently.

  19. Evaluation of abiotic stresses of temperate estuaries by using resident zooplankton: A community vs. population approach

    Science.gov (United States)

    Paul, Sourav; Wooldridge, Tris; Perissinotto, Renzo

    2016-03-01

    By using permanently resident zooplankton, we assessed the ecological level (i.e. community and or population) that provides more in-depth indication of the stress related to salinity and temperature fluctuations in temperate estuaries. In the semi-arid warm temperate South Africa, the Gamtoos estuary experiences a full salinity gradient maintained by irregular but relatively frequent freshwater pulses, whereas the Kromme estuary is euhaline throughout its extent and receives only occasional freshwater inputs when the storage reservoir six km upstream overtops. Changes in the species evenness index of Pielou and the abundances of estuarine resident zooplankton species were modelled against salinity and temperature variations of respective estuaries. In the Gamtoos estuary, response of individual populations provided more in-depth information regarding zooplankton variability. However the most abundant resident zooplankton i.e. Acartia longipatella a copepod was not the best predictor of the salinity and temperature fluctuations. Conversely, the Kromme estuary study provided insights into the potential vulnerability of the resident estuarine zooplankton community to cold. Further, the population level study exposed responses of specific species against salinity changes. We discuss the pros and cons of designing ecological indicators of abiotic stress based on specific species, targeted to specific ecological level, and needs of considering the frequency and magnitude of fresh water inflow in an estuary. A suggestion is to use specific taxonomic group(s) (e.g. Copepods) to better understand the abiotic stress factors of specific set of estuaries (e.g. freshwater rich/starved) until a 'one size fits all' indicator is found for temperate estuaries.

  20. Food web analysis in two permanently open temperate estuaries: consequences of saltmarsh loss?

    Science.gov (United States)

    Svensson, Carl J; Hyndes, Glenn A; Lavery, Paul S

    2007-09-01

    Saltmarsh vegetation, seston and microphytobenthos are all conspicuous components of most temperate estuaries and they potentially contribute to the estuarine food chain. Yet their relative contributions are unclear, as is the significance of saltmarsh losses through natural and human-induced impacts. This study aimed to quantitatively determine the contribution of various types of primary producers to detritus in the Walpole-Nornalup Estuary and Leschenault Inlet, two permanently open estuaries in SW Australia, and, estimate the flow of different types of detritus to higher trophic levels, using carbon ((13)C) and nitrogen ((15)N) stable isotopes as tracers. Results of the mixing model indicated that seston, microphytobenthos and to some extent seagrass and fringing saltmarsh were the main contributors to the detrital pool in both estuaries. However, the relative contribution of different primary producers varied both within and between estuaries. The contribution of saltmarsh was higher at sites close to rivers and dense fringing vegetation, while seston, microphytobenthos and seagrass dominated the detrital material at other sites. Benthic harpacticoid copepods were shown to feed on detritus though they appeared to actively select for different components of the detritus depending on site and estuary. Isotopic signatures of other consumers indicated that fish and invertebrates derived nutrients from MPB and detritus, either directly as food or indirectly through feeding on invertebrates. The overall contribution of saltmarsh to detritus was lower in Leschenault Inlet than in Walpole-Nornalup Estuary, possibly as a result of increased clearing of fringing vegetation around Leschenault Inlet. This pattern was however not reflected in harpacticoid food. Therefore, although losses of fringing saltmarsh around estuaries have the potential to significantly affect estuarine food webs, the significance of such losses will be site- and estuary-dependent. PMID:17382379

  1. Spatial Analysis of BioAmbients

    DEFF Research Database (Denmark)

    Nielson, Hanne Riis; Nielson, Flemming; Pilegaard, Henrik

    Programming language technology can contribute to the development and understanding of Systems Biology by providing formal calculi for specifying and analysing the dynamic behaviour of biological systems. Our focus is on BioAmbients, a variation of the ambient calculi developed for modelling...

  2. Control Flow Analysis for BioAmbients

    DEFF Research Database (Denmark)

    Nielson, Flemming; Nielson, Hanne Riis; Priami, C.; Rosa, D. Schuch da

    2007-01-01

    This paper presents a static analysis for investigating properties of biological systems specified in BioAmbients. We exploit the control flow analysis to decode the bindings of variables induced by communications and to build a relation of the ambients that can interact with each other. We...

  3. Context Dependent Analysis of BioAmbients

    DEFF Research Database (Denmark)

    Pilegaard, Henrik; Nielson, Flemming; Nielson, Hanne Riis

    2006-01-01

    BioAmbients is a derivative of mobile ambients that has shown promise of describing interesting features of the behaviour of biological systems. The technical contribution of this paper is to extend the Flow Logic approach to static analysis with a couple of new techniques in order to give precise...

  4. Ambient air pollution and low birthweight

    DEFF Research Database (Denmark)

    Pedersen, Marie; Giorgis-Allemand, Lise; Bernard, Claire;

    2013-01-01

    BACKGROUND: Ambient air pollution has been associated with restricted fetal growth, which is linked with adverse respiratory health in childhood. We assessed the effect of maternal exposure to low concentrations of ambient air pollution on birthweight. METHODS: We pooled data from 14 population...

  5. INTERPOLATING VANCOUVER'S DAILY AMBIENT PM 10 FIELD

    Science.gov (United States)

    In this article we develop a spatial predictive distribution for the ambient space- time response field of daily ambient PM10 in Vancouver, Canada. Observed responses have a consistent temporal pattern from one monitoring site to the next. We exploit this feature of the field b...

  6. Hybrid Logical Analyses of the Ambient Calculus

    DEFF Research Database (Denmark)

    Bolander, Thomas; Hansen, Rene Rydhof

    2010-01-01

    In this paper, hybrid logic is used to formulate three control flow analyses for Mobile Ambients, a process calculus designed for modelling mobility. We show that hybrid logic is very well-suited to express the semantic structure of the ambient calculus and how features of hybrid logic can be...

  7. Minimal ambient nuclear C*-algebras

    OpenAIRE

    Suzuki, Yuhei

    2015-01-01

    We provide examples of ambient nuclear C*-algebras of non-nuclear C*-algebras with no proper intermediate C*-algebras. In particular this gives the first examples of minimal ambient nuclear C*-algebras of non-nuclear C*-algebras. For this purpose, we study generic Cantor systems of infinite free product groups.

  8. An evaluation of the bioavailability and aquatic toxicity attributed to ambient copper concentrations in surface waters from several parts of the world.

    Science.gov (United States)

    Van Genderen, Eric; Adams, William; Cardwell, Rick; van Sprang, Patrick; Arnold, Ray; Santore, Robert; Rodriguez, Patricio

    2008-10-01

    Ambient concentrations of metals in surface waters have become an important consideration when establishing water quality criteria and conducting risk assessments. This study sought to estimate amounts of copper that may be released into fresh and estuarine waters considering ambient concentrations, toxicity thresholds, and bioavailability. Cumulative distribution functions of ambient copper concentrations were compared statistically for individual sites within 14 surface waters of North America and Europe to identify differences among mean distribution variables (e.g., slopes, intercepts, and inflection points). Results illustrated that the majority of distributions among sites differed significantly. These differences illustrate the variability in ambient copper concentrations in surface waters due to geographic location, regional geology, and anthropogenic influence. Additionally, surface water quality data were used for streams and lakes in Chile, Europe, and North America (including 1 saltwater estuary) to estimate bioavailable copper concentrations in ambient surface waters (based on predictions using biotic ligand models). The amount of dissolved metal that could be added to surface waters without exceeding toxicity thresholds was calculated by subtracting ambient surface water concentrations from chronic (reproduction) no-observable-effect concentrations (NOEC) for Daphnia magna using the freshwater data and 48-h median-effect (normal shell development) concentrations (EC50) for Mytilus edulis using that for saltwater. Because ambient dissolved copper concentrations were, on average, only a small fraction (18%) of predicted effects threshold, an average of 14 +/- 17 microg/L (+/-SD) of copper could be added before exceeding the D. magna chronic NOEC or the M. edulis EC50. However, several sites were identified as having ambient copper concentrations in excess of these toxicity thresholds. The risks posed by copper to sensitive indicator species in surface

  9. Linking biogeochemistry to hydro-geometrical variability in tidal estuaries: a generic modeling approach

    Science.gov (United States)

    Volta, Chiara; Gildas Laruelle, Goulven; Arndt, Sandra; Regnier, Pierre

    2016-03-01

    This study applies the Carbon-Generic Estuary Model (C-GEM) modeling platform to simulate the estuarine biogeochemical dynamics - in particular the air-water CO2 exchange - in three idealized tidal estuaries characterized by increasing riverine influence, from a so-called "marine estuary" to a "riverine estuary". An intermediate case called "mixed estuary" is also considered. C-GEM uses a generic biogeochemical reaction network and a unique set of model parameters extracted from a comprehensive literature survey to perform steady-state simulations representing average conditions for temperate estuaries worldwide. Climate and boundary conditions are extracted from published global databases (e.g., World Ocean Atlas, GLORICH) and catchment model outputs (GlobalNEWS2). The whole-system biogeochemical indicators net ecosystem metabolism (NEM), C and N filtering capacities (FCTC and FCTN, respectively) and CO2 gas exchanges (FCO2) are calculated across the three idealized systems and are related to their main hydrodynamic and transport characteristics. A sensitivity analysis, which propagates the parameter uncertainties, is also carried out, followed by projections of changes in the biogeochemical indicators for the year 2050. Results show that the average C filtering capacities for baseline conditions are 40, 30 and 22 % for the marine, mixed and riverine estuary, respectively, while N filtering capacities, calculated in a similar fashion, range from 22 % for the marine estuary to 18 and 15 % for the mixed and the riverine estuaries. Sensitivity analysis performed by varying the rate constants for aerobic degradation, denitrification and nitrification over the range of values reported in the literature significantly widens these ranges for both C and N. Simulations for the year 2050 suggest that all estuaries will remain largely heterotrophic, although a slight improvement of the estuarine trophic status is predicted. In addition, our results suggest that, while the

  10. Carbon budgets for two Portuguese estuaries: implications for the management and conservation of coastal waters

    OpenAIRE

    Oliveira, Ana P

    2014-01-01

    Abstract: Carbon budgets vary markedly within and between Tagus and Sado estuaries reflecting the human pressure. These estuaries seem to generate carbon within a total of 0.13 MtC yr-1 for Tagus and 0.02 MtC yr-1 for Sado. Anthropogenic inputs, autochthonous carbon production and primary production are indicated as the main responsible for the carbon production within the estuaries. Carbon exported to the ocean and to the atmosphere by both estuarine systems is higher during the non-producti...

  11. Greenhouse gas (N2O) emission from Portuguese estuaries

    OpenAIRE

    Célia Gonçalves

    2014-01-01

    Abstract: The contribution of nitrous oxide (N2O) emissions to the estuarine nitrogen (N) balance are investigated for Tagus (May 2006), Minho and Lima estuaries (September 2006). N load to Tagus (3.48 Mg N yr-1) and Minho (3.25 Mg N yr-1) are similar in both estuaries but higher then Lima (0.34 Mg N yr-1), being well related to freshwater inflow. Estuaries act as sink of N. In Tagus and Minho most of the N is removed within the system (67% to 70%), while in Lima this value falls to 38.6 %. A...

  12. Modelling nitrogen and phosphorus cycles and dissolved oxygen in the Zhujiang Estuary Ⅱ. Model results

    Institute of Scientific and Technical Information of China (English)

    Guan Weibing; Wong Lai-Ah; Xu Dongfeng

    2001-01-01

    In the present study, the ecosystem-based water quality model was applied to the Pearl River (Zhujiang) Estuary. The model results successfully represent the distribution trend of nutrients and dissolved oxygen both in the horizontal and vertical planes during the flood season, and it shows that the model has taken into consideration the key part of the dynamical, chemical and biological processes existing in the Zhujiang Estuary. The further studies illustrate that nitrogen is in plenty while phosphorus and light limit the phytoplankton biomass in the Zhujiang Estuary during the flood season.

  13. Modeling 226Ra behaviour in a Spanish estuary affected by the phosphate industry

    International Nuclear Information System (INIS)

    The behaviour of 226Ra in a system like this estuary is complex since radionuclides are affected by tidal actions and interactions with sediments through adsorption/desorption reactions and erosion/deposition processes. A numerical 2D depth-averaged model of the estuary has been developed, including processes mentioned above. It has been applied to reproduce experimental data measured after a release from the industrial complex in the Odiel River and after an accidental release in the Tinto River from the gypsum piles. The model has also been applied to simulate the self-cleaning process observed in the estuary after the direct releases from the fertilizer complex were stopped

  14. A Numerical Study of Local Variations in Tidal Regime of Tagus Estuary, Portugal

    OpenAIRE

    Dias, João Miguel; Valentim, Juliana Marques; Sousa, Magda Catarina

    2013-01-01

    Tidal dynamics of shallow estuaries and lagoons is a complex matter that has attracted the attention of a large number of researchers over the last few decades. The main purpose of the present work is to study the intricate tidal dynamics of the Tagus estuary, which states as the largest estuary of the Iberian Peninsula and one of the most important wetlands in Portugal and Europe. Tagus has large areas of low depth and a remarkable geomorphology, both determining the complex propagation of t...

  15. Food web dynamics in a temperate temporarily open/closed estuary (South Africa)

    Science.gov (United States)

    Froneman, P. W.

    2004-01-01

    Size fractionated chlorophyll- a (chl- a), primary production and zooplankton (mesozooplankton (200-2000 μm) and microheterotrophs (freshwater inflow into the estuary. The inflow of freshwater into the estuary also coincided with a shift in the size structure of the phytoplankton community with large cells (>5 μm) dominating total chl- a and production. During periods of reduced freshwater inflow into the estuary, total chl- a and production were dominated by small (preferred food particle size between the microheterotrophs and mesozooplankton.

  16. Ordenamento jurídico ambiental

    OpenAIRE

    Costa, Paulo Manuel

    2014-01-01

    Neste artigo iremos fazer uma breve análise das normas jurídicas mais importantes para a protecção do ambiente. Para isso, começaremos por conhecer as principais normas sobre o ambiente que constam da Constituição Portuguesa e que constituem a denominada «Constituição do ambiente». Depois iremos ver um pouco mais em pormenor a Lei de Bases da Política do Ambiente, a qual enuncia os princípios, as medidas e as políticas orientadoras da protecção jurídica do ambiente. Por fim, iremos examinar o...

  17. Trace metal partitioning over a tidal cycle in an estuary affected by acid mine drainage (Tinto estuary, SW Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Hierro, A. [Department of Physics, Universitat Autònoma de Barcelona, 08193 Bellaterra (Spain); Department of Applied Physics, Facultad de Ciencias Experimentales, University of Huelva, Campus de El Carmen, Campus de Excelencia Internacional del Mar CEIMAR, 21071 Huelva (Spain); Olías, M., E-mail: manuel.olias@dgyp.uhu.es [Department of Geodynamics and Paleontology, Facultad de Ciencias Experimentales, University of Huelva, Campus de El Carmen, Campus de Excelencia Internacional del Mar CEIMAR, 21071 Huelva (Spain); Cánovas, C.R. [Department of Geodynamics and Paleontology, Facultad de Ciencias Experimentales, University of Huelva, Campus de El Carmen, Campus de Excelencia Internacional del Mar CEIMAR, 21071 Huelva (Spain); Martín, J.E.; Bolivar, J.P. [Department of Applied Physics, Facultad de Ciencias Experimentales, University of Huelva, Campus de El Carmen, Campus de Excelencia Internacional del Mar CEIMAR, 21071 Huelva (Spain)

    2014-11-01

    The Tinto River estuary is highly polluted with the acid lixiviates from old sulphide mines. In this work the behaviour of dissolved and particulate trace metals under strong chemical gradients during a tidal cycle is studied. The pH values range from 4.4 with low tide to 6.9 with high tide. Precipitation of Fe and Al is intense during rising tides and As and Pb are almost exclusively found in the particulate matter (PM). Sorption processes are very important in controlling the mobility (and hence bioavailability) of some metals and particularly affect Cu below pH 6. Above pH ∼ 6 Cu is desorbed, probably by the formation of Cu(I)–chloride complexes. Although less pronounced than Cu, also Zn desorption above pH 6.5 seems to occur. Mn and Co are affected by sorption processes at pH higher than ca. 6. Cd behaves conservatively and Ni is slightly affected by sorption processes. - Highlights: • The Tinto estuary shows strong pH gradients and high trace elements concentrations. • PM has a hysteretic relationship with tides and high contents of Fe, Al, As and Pb. • Co and Mn are controlled by river and sea water mixing and sorption processes. • Sorption processes strongly affect Cu below pH 6, above this value Cu is desorpted. • Cadmium behaves conservatively along the pH range studied (4.4–6.9)

  18. Trace metal partitioning over a tidal cycle in an estuary affected by acid mine drainage (Tinto estuary, SW Spain)

    International Nuclear Information System (INIS)

    The Tinto River estuary is highly polluted with the acid lixiviates from old sulphide mines. In this work the behaviour of dissolved and particulate trace metals under strong chemical gradients during a tidal cycle is studied. The pH values range from 4.4 with low tide to 6.9 with high tide. Precipitation of Fe and Al is intense during rising tides and As and Pb are almost exclusively found in the particulate matter (PM). Sorption processes are very important in controlling the mobility (and hence bioavailability) of some metals and particularly affect Cu below pH 6. Above pH ∼ 6 Cu is desorbed, probably by the formation of Cu(I)–chloride complexes. Although less pronounced than Cu, also Zn desorption above pH 6.5 seems to occur. Mn and Co are affected by sorption processes at pH higher than ca. 6. Cd behaves conservatively and Ni is slightly affected by sorption processes. - Highlights: • The Tinto estuary shows strong pH gradients and high trace elements concentrations. • PM has a hysteretic relationship with tides and high contents of Fe, Al, As and Pb. • Co and Mn are controlled by river and sea water mixing and sorption processes. • Sorption processes strongly affect Cu below pH 6, above this value Cu is desorpted. • Cadmium behaves conservatively along the pH range studied (4.4–6.9)

  19. EL RACISMO AMBIENTAL EN CHILE

    Directory of Open Access Journals (Sweden)

    MATÍAS MEZA-LOPEHANDÍA

    2011-06-01

    Full Text Available El problema de la desigualdad en Chile ha sido abordado desde diferentes puntos de vista como la cuestión de la distribución de la riqueza o el acceso a los derechos sociales. Es este trabajo se observa el mismo problema pero desde la perspectiva recientemente esbozada por los movimientos sociales: la del racismo ambiental o la desigual distribución de los deshechos del desarrollo y el consumo. De esta manera se revisan sucintamente los principales conflictos que han surgido en el último tiempo a lo largo del país entre empresas públicas y privadas y comunidades locales y originarias. Así mismo se examinan las formas de organización que estas últimas han asumido y el estado actual de articulación entre ellas. De la revisión de la situación se concluye que estamos ante el surgimiento de un actor de nuevo tipo, que surge de las contradicciones del Chile neoliberal y que se diferencia del movimiento ecologista por vincular sus reivindicaciones a la defensa del territorio y al derecho a la autodeterminación de los pueblos.

  20. Distribution, provenance and early diagenesis of major and trace metals in sediment cores from the Mandovi estuary, western India

    Science.gov (United States)

    Prajith, A.; Rao, V. Purnachandra; Chakraborty, P.

    2016-03-01

    Major elements and trace metals were analyzed in four sediment cores recovered along a transect in the Mandovi estuary for their distribution, provenance and early diagenesis. The sediments were clayey silts in cores from the upper/lower estuary and sand-dominated in cores from the middle estuary/bay. Organic carbon (OC) content varied from 0.5 to 4%, with higher values in fine-grained sediments. The mean Fe and Mn contents of sediments from the upper/middle estuary were 3-5 times and 8-13 times, respectively higher than the reference sediment (RS) from the same estuary. The mean Fe and Mn contents of sediments from the lower estuary/bay were close to the RS. Strong inter-metal correlation among Ti, V, Cr and Zr in all the cores indicated their contribution from a common source, probably the laterites from hinterland. Trace metals were more enriched in fine-grained sediments than in sand-dominated sediments. Early diagenetic control on the redistribution of metal is evident in core sediments from the middle estuary to Bay. The distribution of Mo, U and Pb followed that of Fe and Mn in the upper estuary and OC in the lower estuary/bay. Our results indicated strong anthropogenic contribution of metals from ore deposits in the upper/middle estuary. The Mn and Cr contents of sediment in the upper/middle estuary and Fe in the middle estuary were highly enriched suggestive of 'significant pollution signal'. More trace metals from the middle estuary were moderately enriched. Speciation studies showed Mn and Pb occurred abundantly in non-residual phases. High Mn content and its high percentage in exchangeable and reductive phases indicate that it was susceptible to be mobilized. However, Fe, Cu and Ni occurred abundantly in residual phases and less percentage of them were expected to be bio-available.

  1. Plutonium and cesium radionuclides in the Hudson River estuary. Annual technical progress report, December 1, 1976--November 30, 1977

    International Nuclear Information System (INIS)

    We have obtained a large set of sediment cores from the Hudson estuary through much of the ambient salinity range. A number of core sections and samples of suspended particles have been analyzed for 137Cs, 134Cs and 60Co by direct gamma counting, and 239Pu, 240Pu, and 238Pu by alpha spectrometry. The distribution of both 137Cs and 239Pu, 240Pu indicates rapid accumulation in marginal cover areas, and especially in the harbor region adjacent to New York City. The distributions of both 137Cs and 239Pu, 240Pu are similar in surface sediments and with depth in cores, but there are deviations from the fallout ratio due to addition of reactor 137Cs and loss of 137Cs from the particle phases at higher salinities. Measureable amounts of reactor-derived 134Cs and 60Co are found in nearly all sediment samples containing appreciable 137Cs, between 15 km upstream of Indian Point and the downstream extent of our sampling, 70 km south of the reactor. Accumulations of 239Pu, 240Pu in New York harbor sediments are more than an order of magnitude greater than the fallout delivery rate. The most likely explanation is accumulation of fine particles in the harbor which have been transported from upstream areas of the Hudson. Our evidence so far indicates that Indian Point is probably not a significant source of 239Pu, 240Pu or 238Pu compared with the fallout burden of these nuclides already in the sediments

  2. Plutonium and cesium radionuclides in the Hudson River Estuary. Annual technical progress report, December 1, 1974--November 30, 1975

    International Nuclear Information System (INIS)

    We have obtained a large set of gravity cores from the Hudson Estuary through much of the ambient salinity range. A number of core sections have been analyzed for 137Cs, 134Cs, 60Co, and 40K by direct gamma counting, and for 239,240Pu by alpha-spectrometry. The distribution of both 137Cs and 239,240Pu indicates rapid accumulation in marginal cove areas and in the harbor region adjacent to New York City. The distribution of both 137Cs and 239,240Pu in the sediments is quite similar in surface sediments, and the trends with depth in cores are also similar. The ratio of sediment 239,240Pu to 137Cs throughout the sampled salinity range (0-20 0/00) approximates that in fallout, except near the nuclear reactor at Indian Point where releases of 137Cs result in a ratio lower (0.004 to 0.008) than typical of fallout (0.015). Measurement amounts of reactor-derived 134Cs, 60Co, and 54Mn are found in nearly all of the samples containing appreciable 137Cs. These samples were between 15 km upstream of Indian Point reactor site and the downstream extent of our sampling, 70 km south of the reactor

  3. Tides in the Mandovi and Zuari estuaries, Goa, west coast of India

    Indian Academy of Sciences (India)

    D Sundar; S R Shetye

    2005-10-01

    Mandovi and Zuari are two estuaries located in Goa,west coast of India.Variation of water level in the estuaries was monitored for a month at 13 locations using tide-poles during March –April 2003.Analysis of this data has provided for the first time,characteristics of how tidal constituents vary in the narrow and shallow estuaries,typical of those found along the west coast of India.At a distance of 45 km from the mouth the tidal range increased in both estuaries by approximately 20%.The tidal range at the upstream end of the two channels at the stations dropped sharply because of the increase in elevation of the channels.

  4. Study of age and growth of Indian sand whiting, sillago sihama (Forsskal) from Zuari estuary, Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Shamsan, E.F.; Ansari, Z.A

    Present study consists age and growth of Sillago sihama. Total 1465 fish were collected from Zuari estuary during January 2004-April 2005 as a part of the above study. To evaluate the age at corresponding length, length frequency distribution (LFD...

  5. Influence of river discharge on plankton metabolic rates in the tropical monsoon driven Godavari estuary, India

    Digital Repository Service at National Institute of Oceanography (India)

    Sarma, V.V.S.S.; Gupta, S.N.M.; Babu, P.V.R.; Acharyya, T.; Harikrishnachari, N.; Vishnuvardhan, K.; Rao, N.S.; Reddy, N.P.C.; Sarma, V.V.; Sadhuram, Y.; Murty, T.V.R.; Kumar, M.D.

    2008) at a fixed location (Yanam) in the Godavari estuary, India. River discharge was at its peak during July to September with a sharp decrease in the middle of December and complete cessation thereafter. Significant amount of dissolved inorganic...

  6. Sediment Data from Great Bay Estuary, New Hampshire (ARMSTRONG74 shapefile)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The sediment data presented in this data layer were from a geochemical study sited in Great Bay Estuary, New Hampshire. The analog data were originally converted...

  7. Characteristics of Sediments in the James River Estuary, Virginia, 1968 (NODC Accession 7001081)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This report presents data on the physical and chemical characteristics of bottom sediments in the James River estuary, Virgina. The data were generated as part of a...

  8. Diel-Cycling Hypoxia in Northern Gulf of Mexico Estuaries: Impacts and Protection of Aquatic Life

    Science.gov (United States)

    Eutrophication of coastal ecosystems is a longstanding environmental concern, exacerbated by population growth and associated nutrient pollution, and ultimately resulting in increased incidence of hypoxia. Shallow and highly productive estuaries and embayments are particularly su...

  9. Modeling transportation of suspended solids in Zhujiang River estuary, South China

    Institute of Scientific and Technical Information of China (English)

    CHEN Xiaohong; CHEN Yongqin; LAI Guoyou

    2005-01-01

    A three-dimensional transportation model for suspended solids (SS) in Zhujiang (Pearl) River estuary, South China, was developed by coupling with a three-dimensional hydrodynamic model. The model was validated using hourly measured data of sediment contents during 25-26, July 1999. The results showed that modeled contents matched well with measured ones and that the modeled top layer distribution agreed with the remotely sensed image of suspended solids in summer. The modeled results showed clearly the layers of suspended solids in depth, with larger sediment contents in lower layers though in the interface between salt water and freshwater the lowest contents appeared in middle layer. In overall, the suspended solids inflow from 8 rivers, transport southwestward, and carried by strong coastal flow in Zhujiang River estuary. Contours of sediment contents in the estuary spread further to the open sea during ebb tide rather than flood tide which reflects that the suspended solids in the estuary are land sourced.

  10. Freshwater flushing time scales of the Vashishti Estuary, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    DineshKumar, P.K.; Sarma, R.V.; Zingde, M.D.

    method indicated that the load retained in the estuary after infinite number of tidal cycles was 44 to 54 times the load introduced per tidal cycles during premonsoon and 47 to 61 times during postmonsoon periods. Calculations on longitudinal diffusion...

  11. CREEK Project's Oyster Biomass Database for Eight Creeks in the North Inlet Estuary, South Carolina

    Data.gov (United States)

    Baruch Institute for Marine and Coastal Sciences, Univ of South Carolina — A group of eight tidal creeks dominated by oysters, Crassostrea virginica, in North Inlet Estuary, South Carolina, USA were studied using a replicated BACI (Before...

  12. Drought-induced variability in dissolved organic matter composition in a marsh-dominated estuary

    Science.gov (United States)

    Medeiros, Patricia M.; Seidel, Michael; Dittmar, Thorsten; Whitman, William B.; Moran, Mary Ann

    2015-08-01

    The composition of dissolved organic matter (DOM) in an estuary characterized by extensive salt marsh vegetation was investigated at the molecular level using ultrahigh-resolution mass spectrometry and stable carbon isotope analyses. Samples from multiple seasons covered different hydrological regimes, including anomalously low-discharge conditions. The untargeted approach used allowed for identifying the DOM molecular signatures associated with different DOM sources in the estuary. DOM composition was strongly modulated by river discharge at monthly scales, with high river flow leading to significant increases in the terrigenous signature of the DOM throughout the estuary. During a severe/exceptional drought, estuarine DOM was imprinted with a distinct signature of marsh-derived compounds. The frequency of occurrence of anomalously low-discharge conditions seems to have increased over the last decades. If predictions of anthropogenically driven changes in hydroclimate are confirmed, they will likely be accompanied by changes in DOM composition in estuaries at multidecadal time scales.

  13. National Status and Trends: Bioeffects Assessment Program, St Lucie Estuary Summary Database (2001-2004)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The foundation of this study was based on a sediment quality triad (SQT) approach with a probabilistic sampling design, which characterized the estuary in terms of...

  14. Fin Fish Biodiversity Of A Tropical Sal Estuary, Goa, West Coast Of India

    Directory of Open Access Journals (Sweden)

    Nandadeep U. Fal Dessai

    2013-09-01

    Full Text Available Sal estuary represents rich biodiversity because of the heavy rains during the south west monsoon and lack of any industrial development along the banks of the river. Attempt was made to survey the fin fish biodiversity along the estuary to fulfill the lack of adequate information regarding estuarine fisheries. Hydrological parameters were analysed during the study period and found to be highly influencing. Fishes were caught near shore by using gill nets and cast nets. About 35 fin fishes were recorded belonging to 28 families. The distribution varies according to the environmental conditions. Some of the important fin fishes found in this estuary are Mugil cephalus, Gerres filamentosus, Sillago sihama, Etroplus suratensis, Arius arius, Lutjanus argentimaculatus, Acanthopagrus berda and Lobotes surinamensis. Some of the fresh water species are also observed in the Sal river. In future, Industrialization along the bank of the estuary may threaten the species diversity and need necessary laws for conservation of biodiversity

  15. Drivers of Variability of Diel-Cycling and Episodic Hypoxia In Northern Gulf of Mexico Estuaries

    Science.gov (United States)

    Eutrophication of coastal ecosystems is a longstanding environmental concern, exacerbated by population growth and associated nutrient pollution, and ultimately resulting in increased incidence of hypoxia. Shallow and highly productive estuaries and embayments are particularly su...

  16. Temporal and Spatial Dynamics of Diel-Cycling Hypoxia in Four Northern Gulf of Mexico Estuaries

    Science.gov (United States)

    Eutrophication of coastal ecosystems has accelerated in recent decades due to population growth and associated nutrient pollution, resulting in increased incidence of hypoxia. Shallow and highly productive estuaries and embayments are particularly susceptible to diel-cycling hypo...

  17. Tidal circulation and salinity distribution in the Mandovi and Zuari estuaries: Case study

    Digital Repository Service at National Institute of Oceanography (India)

    Manoj, N.T.; Unnikrishnan, A.S.

    was to study the intraseasonal variations of salinity during the breaks in the southwest monsoon. A hybrid network numerical model was used for the present study to simulate the tidal circulation and the salinity distribution in these estuaries. The model...

  18. 2009 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Snohomish River Estuary

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. (WS) co-acquired Light Detection and Ranging (LiDAR) data and Truecolor Orthophotographs of the Snohomish River Estuary, WA on July 20...

  19. Physical aspects of estuarine pollution - A case study in Amba river estuary

    Digital Repository Service at National Institute of Oceanography (India)

    DineshKumar, P.K.; Josanto, V.; Sarma, R.V.; Zingde, M.D.

    Tide dominated Amba river estuary was studied to evaluate it's physical characteristics with a point on application to locate a suitable release point of industrial effluents. It is important to site the outfall in a manner ensuring that the water...

  20. Speciation and behaviour of Cd, Pb and Cu in Zuari Estuary, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    George, M.D.

    Dissolved labile and nonlabile forms of Cd, Pb and Cu in Zuari Estuary, Goa, India measured for a period of 14 months showed lowest concentrations during the SW monsoon (June-September) while maximum concentrations were observed during...

  1. An analysis of MODIS algorithms for surface salinity and dissolved organic carbon in northwest Florida estuaries

    Science.gov (United States)

    Synoptic and frequent monitoring of water quality parameters from satellite is useful for determining the health of aquatic ecosystems and development of effective management strategies. Northwest Florida estuaries are classified as optically-complex, or waters influenced by chlo...

  2. PARASITIC AND SYMBIONIC FAUNA IN OYSTERS (CRASSOSTREA VIRGINICA) COLLECTED FROM THE CALOOSAHATCHEE RIVER AND ESTUARY, FLORIDA

    Science.gov (United States)

    Studies of oysters, Crassostrea virginica, collected from ten sites in the Caloosahatchee River and Estuary, Florida, revealed a varied parasite and symbiotic fauna that have never been reported from this area. Organisms observed included ovacystis virus infecting gametes...

  3. Observed mixed standing-wave signatures in Cochin Estuary on the southwest coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    DineshKumar, P.K.; Srinivas, K.; Muraleedharan, K.R.; Thottam, T.J.

    Study of the characteristics of currents and water-level variations in the Cochin estuary reveals, for the first time, unique signatures of mixed standing-waves in the southern region. Analysis of the simultaneous water-level data generated...

  4. Seasonal variability in penaeid prawn larval abundance in the Mandovi and Zuari estuaries, Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Goswami, S.C.; Goswami, U.

    Seasonal variations in the occurrence and abundance of penaeid prawn larvae in the Mandovi and Zuari estuaries of Goa, India were studied. Larvae and postlarvae of commercially important species viz. Metapenaeus dobsoni (Miers), M. affinis (H. Milne...

  5. An autonomous underwater vehicle "Maya", for monitoring coastal waters, estuaries, rivers and dams

    Digital Repository Service at National Institute of Oceanography (India)

    Mascarenhas, A.A.M.Q.; Navelkar, G.S.; Madhan, R.; Dabholkar, N.A.; Prabhudesai, S.P.; Maurya, P.K.; Desa, E.; Afzulpurkar, S.; Suresh, T.; Matondkar, S.G.P.; Mahalunkar, A.

    This article demonstrates the use of Maya, Autonomous Underwater Vehicle (AUV) for monitoring coastal waters, estuaries, rivers and dams. Maya is a mono hull structure with detachable nose and tail cones. The nose cone is mission specific...

  6. Predicting submerged aquatic vegetation cover and occurrence in a Lake Superior estuary

    Science.gov (United States)

    Submerged aquatic vegetation (SAV) provides the biophysical basis for multiple ecosystem services in Great Lakes estuaries. Understanding sources of variation in SAV is necessary for sustainable management of SAV habitat. From data collected in 2011 using hydroacoustic survey met...

  7. Studies on organic carbon, nitrogen and phosphorous in the sediments of Mandovi Estuary, Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Nasnolkar, C.M.; Shirodkar, P.V.; Singbal, S.Y.S.

    Sediment organic carbon, total nitrogen, total phosphorous and hydrography of the overlying waters of the estuarine region in Mandovi Estuary, Goa, India have been studied. The relationship of carbon and nutrients with sediment characteristics...

  8. San Francisco Estuary Midwinter Waterfowl Survey: 2012 Survey Results and Trend Analysis (1981-2012)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report provides results of the 2012 San Francisco Estuary Midwinter Waterfowl Survey and presents an analysis of trends in waterfowl counts from 1981-2012. The...

  9. Seawater intrusion and behaviour of dissolved boron, fluoride, calcium, magnesium and nutrients in Vashisti Estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Zingde, M.D.; Ram, A.; Sharma, P.; Abidi, S.A.H.

    Behaviour of dissolved B, F, Ca, Mg and nutrients in partially stratified estuary of Vashiti River, Karnataka, India has been studied under stable conditions of riverine flow. The dominance of Mg over Ca concentration in river water resulted...

  10. Heterotrophic utilization of extracellular products of phytoplankton in a tropical estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Gomes, H.; Pant, A; Goes, J.I.; Parulekar, A

    Bacterial uptake of algal exudates has been estimated in a tropical estuary, Dona Paula, Goa, India, where the seasonal fluctuations in hydrographic and nutrient parameters as well as dissolved organic matter concentrations and phytoplankton species...

  11. Ambient Intelligence: Next Generation Technology

    Directory of Open Access Journals (Sweden)

    Anand Chandrasekhar,

    2011-06-01

    Full Text Available Configuration of the computing and communications systems found at home and in the workplace is a complex system design that currently requires the attention of the user. Recently, researchers have begun to explore computers that would autonomously configure their functionality based on observations of who or what is surrounding them. By determining their context, using input from sensor systems distributed throughout the environment, computing devices could personalize themselves to their current user, adapt their behaviouraccording to their location, or interact to their surroundings. This field of intelligence is called Ambient Intelligence (AmI. There has been increasing interest in building networks with AmI, which incorporates the user-centricity and context awareness, or in short AmI is a new information paradigm where people are empowered through a digital environment that is “aware” of their presence, context and is sensitive, adaptive, responsive to their needs and requests. Users’ environments are going to be disseminated of intelligentadaptive devices and sensors that will coordinate each other to help users in their activities with the help of AmI concepts and designs. This paper introduces the concept of AMI, explains the need for such an intelligence and also waves light over the different innovations done in this promising field of science and technology. This paper also addresses the topic of providing context aware services in smart environments. We review recent works in smart environments, and further defines and debates essential aspects concerning context-aware service supply. Future challenges for the research in context-aware smart environments are also discussed.

  12. THE CHARACTERISTIC OF MARINE ENVIRONMENT IN LINGDINGYANG ESTUARY

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Hydrologic features, load of main pollutants and current condition of water quality in Lingdingyang Estu ary are discussed by references and monitoring data. Affected by topography, runoff and tide, its dynamic condition is very complicated. Different water areas have different hydrologic features. The topography under the water of Lingdingyang Estuary is higher in the northwest than that in the southeast. The shoal alternates with the deep trough with in the bay. The distribution of the salinity and the contents of the mud and the main pollutants tally with the topography tendency. Change in water quality goes through four stages. Current condition of water quality is fairly good. Inorganic nitrogen is the primary pollutant, and then phosphorus. Rich in nutrition of nitrogen and phosphorus become a more and more prominent problem.

  13. Guidelines for determining inputs of inorganic contaminants into estuaries

    International Nuclear Information System (INIS)

    This publication describes sampling and sample preparation procedures suitable to obtain unpolluted samples for the purpose of determining river inputs of inorganic pollutants into estuaries. Emphasis is placed on heavy metal pollutants but procedures are suitable, with appropriate modifications for other inorganic pollutants. For example, the collection of samples for mercury may require modifications of handling procedures. River water samples are collected at the most down-river point where no estuarine influences effect results. Samples are collected using a peristaltic pump and separated into aqueous and particulate phases for pollutant analysis. As is the case of all trace pollutant analyses, meticulous care is required to prevent pollution of the sample and in addition to the precautions described in this method, great personal attention is required to minimize sample handling, pollution by smoke, hands, hair, dust, talc from gloves, etc., and to avoid all contact of the samples and reagents with skin and metallic objects. 1 ref., 3 figs, 1 tab

  14. Hydrodynamic and Salinity Intrusion Model in Selangor River Estuary

    Science.gov (United States)

    Haron, N. F.; Tahir, W.

    2016-07-01

    A multi-dimensional hydrodynamic and transport model has been used to develop the hydrodynamic and salinity intrusion model for Selangor River Estuary. Delft3D-FLOW was applied to the study area using a curvilinear, boundary fitted grid. External boundary forces included ocean water level, salinity, and stream flow. The hydrodynamic and salinity transport used for the simulation was calibrated and confirmed using data on November 2005 and from May to June 2014. A 13-day period for November 2005 data and a 6-day period of May to June 2014 data were chosen as the calibration and confirmation period because of the availability of data from the field-monitoring program conducted. From the calibration results, it shows that the model was well suited to predict the hydrodynamic and salinity intrusion characteristics of the study area.

  15. MUVA: a MUltimodal Visceral design Ambient device

    DEFF Research Database (Denmark)

    Kivac, Robert; Øllgaard Klem, Sune; Béneé Olsen, Sophus;

    2016-01-01

    This paper presents MUVA (MUltimodal Visceral design Ambient device), a prototype for a storytelling light- and sound-based ambient device. The aim of this device is to encourage social interaction and expand the emotional closeness in families with children where at least one parent has irregular...... work schedule. MUVA differs from the other ambient devices, because it is targeted to children, and it adopts a visceral design approach in order to be appealing to its users. It is a raindrop-shaped lamp, which features audio playing, while its light color is affected by the audio playing. MUVA can...

  16. Economía y medio ambiente

    OpenAIRE

    Ciro Alfonso Serna Mendoza

    2010-01-01

    En ciertos escenarios académicos, políticos, sociales y ambientales se declara que el modelo económico dominante o los conceptos que lo integran son responsables de que el bienestar económico implique malestar ecológico.Al partir de este supuesto, una forma de comprender las causas y de contribuir a la solución de la problemática ambiental es develar en qué consisten, en qué términos plantean la relación ombre-medio ambiente, las propuestas que incluyen la dimensión ambiental en el campo de l...

  17. Ecología y ambiente

    OpenAIRE

    Malacalza, Leonardo

    2013-01-01

    Ecología y Ambiente es un libro que hemos escrito para quienes comienzan estudios universitarios y también para todos los que estén interesados en iniciarse en temas del medio ambiente. Los contenidos del libro están divididos en dos partes; en la primera estudiamos temas básicos de biología y los fundamentos de la teoría ecológica; en la segunda se describen y analizan algunos grandes temas directamente relacionados con el medio ambiente en que vivimos. Sobre tales temas hemos invitado a ...

  18. Rare earth element analysis indicates micropollutants in an urban estuary

    Science.gov (United States)

    Mohajerin, T. J.; Johannesson, K. H.; Kolker, A.; Burdige, D. J.; Chevis, D.

    2011-12-01

    Rare earth element analysis of Bayou Bienvenue waters shows anomalously high gadolinium, Gd, concentrations relative to its nearest neighbors in the REE series, europium and terbium. The anomalously high Gd concentrations indicate anthropogenic input from waste-water treatment plants in the area as anthropogenic Gd input can be traced back to its use as a contrast agent in magnetic resonance imaging in hospitals. Others have shown that anomalously high levels of Gd in natural waters are likely to be associated with other micropollutants that also occur in hospital effluent and that are not removed in the wastewater treatment process, including pharmaceuticals in the form of steroids, antihistamines, and antibiotics. Estuaries serve as many important ecological roles and have been shown to act as a filter for pollutants. To better understand the transport, biogeochemical cycling, and ultimate fate of trace elements in estuaries, I collected surface water samples from Bayou Bienvenue, a wetland triangle that covers an area of 427 acres directly adjacent to New Orleans, Louisiana. Water samples from Bayou Bienvenue were collected along the salinity gradient and subsequently filtered through progressively smaller pore-size filters. The resulting fractions were analyzed for trace element concentions, including the REEs, by magnetic sector ICP-MS. The attached figure shows the Gd anomaly present in the particulate (>0.45μm) fraction. Upper continental crust (UCC)-normalized plots of colloidal REEs (0.02μm - 0.45μm) fraction is lacking this anomaly indicating anthropogenic Gd is found chiefly in the particulate fraction in Bayou Bienvenue. No clear relationship between Gd concentration and salinity was apparent.

  19. Sources, distribution and preservation of organic matter in a tropical estuary (Godavari, India)

    Digital Repository Service at National Institute of Oceanography (India)

    Krishna, M.S.; Naidu, S.A.; Subbaiah, Ch.V.; Gawade, L.; Sarma, V.V.S.S.; Reddy, N.P.C.

    , not well understood due to complex interactions between various physical, chemical and biological processes that govern the 3    composition, distribution and processing of OM in estuaries (Deegan et al. 1985; Sharp et al. 1986; Hobbie 2000). Sources... the proportional contribution from each source, and (ii) to identify the controlling mechanism for distribution and preservation of OM in sediments of the Godavari estuary. We hypothesize that there are several physical and biological processes controlling...

  20. Reproductive biology of Sciades herzbergii (Siluriformes: Ariidae) in a tropical estuary in Brazil

    OpenAIRE

    Queiroga, Fernando R.; Jéssica E. Golzio; Raphaela B. dos Santos; Tayná O. Martins; Ana Lúcia Vendel

    2012-01-01

    The present study investigated the reproductive biology of Sciades herzbergii in the Paraíba do Norte River Estuary, Brazil. We aimed to characterize the reproduction of the species with respect to sex ratio, spawning season, condition factor and length at first maturity. Specimens were captured between August 2009 and July 2010 in a stretch of the main channel of the estuary. In the laboratory, they were measured, weighed and macroscopically classified with regard to sex and gonad developmen...

  1. Estimating minimum environmental flow requirements for well-mixed estuaries in Spain

    Science.gov (United States)

    Peñas, Francisco J.; Juanes, José A.; Galván, Cristina; Medina, Raúl; Castanedo, Sonia; Álvarez, César; Bárcena, Javier F.

    2013-12-01

    Following the principles of the European Water Framework Directive, the current Spanish water management legislation requires the definition of the environmental flow regimes for all water bodies, including estuaries. The scientific community has tried to answer the question of how much freshwater an estuary needs since the mid-1970s, resulting in the development of several methodologies and approaches in different parts of the world. However the ability to reproduce most of these approaches is difficult due to the scarcity of required data and also to the differences between the studied estuaries. In this paper, we present a methodology to calculate environmental flow regimes in well-mixed estuaries based on the numerical modelling of salinity and which takes into account the seasonal climatic and hydrologic pattern of the catchment. The approach follows three sequential steps: 1) Definition of reference conditions based on the unaltered salinity patterns and zoning of the estuary, 2) definition of salinity thresholds and 3) calculation of the minimum flows required to satisfy these thresholds. The application of the methodology to five estuaries on the northern coast of Spain has highlighted the importance of considering the hydrological variability and the division of the estuary into homogeneous zones. Moreover, the studies carried out demonstrate the ineffectiveness of river specific methodologies when used to define environmental flow regimes in several estuaries and periods, and the need to apply specific methodologies. The methodology is based on the principles defined by other already tested approaches, but its greatest advantage lies in the ability to be applied to large scales, when physical and biological data is scarce.

  2. Fin Fish Biodiversity Of A Tropical Sal Estuary, Goa, West Coast Of India

    OpenAIRE

    Nandadeep U. Fal Dessai

    2013-01-01

    Sal estuary represents rich biodiversity because of the heavy rains during the south west monsoon and lack of any industrial development along the banks of the river. Attempt was made to survey the fin fish biodiversity along the estuary to fulfill the lack of adequate information regarding estuarine fisheries. Hydrological parameters were analysed during the study period and found to be highly influencing. Fishes were caught near shore by using gill nets and cast nets. About 35 fin fishes we...

  3. Hydrographic and dissolved oxygen variability in a seasonal Pacific Northwest estuary

    Science.gov (United States)

    Sutherland, David A.; O'Neill, Molly A.

    2016-04-01

    Hypoxia is an issue of growing concern for coastal communities. In the California Current System, a prototypical eastern boundary current, attention has been focused on explaining the trend of increasing shelf hypoxia. Despite the regional focus on hypoxia in eastern boundary regions, relatively few studies have examined smaller estuarine systems. Here, we present results from an observational study in Coos Bay, a small estuary on the southern Oregon coast, subject to seasonal upwelling/downwelling winds, strong tides, and wide fluctuations in freshwater input. Coos Bay exhibits characteristics of a salt-wedge type estuary under high river discharge conditions (>150 m3 s-1), a well-mixed estuary under low discharge conditions (0-30 m3 s-1), and partially-mixed estuary during times of moderate discharge (30-150 m3 s-1). The observed vertical stratification and along-estuary salinity gradients correlate significantly with river discharge and tidal forcing. Despite a strong coupling with coastal waters where hypoxia has been present, we do not find evidence for pervasive hypoxia in Coos Bay. We find that upwelling on the shelf advects low dissolved oxygen water into the estuary on synoptic timescales. Early in the upwelling season (April and May), dissolved oxygen minima are found at the estuary mouth, while later in the summer (September), dissolved oxygen minima are found at the riverine end, presumably due to decreased discharge and increased productivity. However, in a given year, the overall strength of the upwelling season is not a good predictor of low dissolved oxygen levels in the estuary.

  4. Sediment abiotic patterns in current and newly created intertidal habitats from an impacted estuary

    OpenAIRE

    Beauchard, O.; Teuchies, J.; Jacobs, S; E. Struyf; Van der Spiet, T.; P. Meire

    2014-01-01

    The controlled reduced tide system (CRT) is a new technique for restoring tidal marshes and is being tested in the Schelde estuary (Belgium). Biogeochemical processes within a CRT were hypothesized to support and improve several estuarine functions such as sediment trapping and nutrient burial. In 2006, the first pilot CRT was implemented in the freshwater zone of the estuary. Fifteen sediment physicochemical descriptors were intensively monitored over 3 years in the newly created CRT and in ...

  5. Nitrification in the Schelde estuary: methodological aspects and factors influencing its activity

    OpenAIRE

    Bie, M.J.M. de; Starink, M.; Boschker, H.T.S.; Peene, J.J.; Laanbroek, H. J.

    2002-01-01

    We present a 15-month dataset on nitrification measurements in the Schelde estuary (Belgium and The Netherlands). Nitrification was estimated using the N-serve sensitive dark 14C-bicarbonate incorporation technique. A peak of nitrification activity was observed in the freshwater part of the estuary. Downstream from this peak, nitrification declined, probably because of ammonium limitation. A range of nitrification inhibitors was tested on both a Nitrosomonas europaea culture and estuarine sam...

  6. Environmental Settings and Harmful Algal Blooms in the Sea Area Adjacent to the Changjiang River Estuary

    OpenAIRE

    Zhou, Mingjiang

    2010-01-01

    The characteristics of the environmental settings of the sea area adjacent to the Changjiang River estuary include complex currents and water masses, the diluted water plume and its redirection, upwelling, front, and nutrients and their sources. The Changjiang River estuary characteristics also include the phytoplankton community, which can affect the growth, migration, assembling, resting and competition of algae to form red tides in this area.. The features of red tide events recorded in th...

  7. OCCURRENCE OF Charybdis hellerii (Milne Edwards, 1867 (CRUSTACEA, DECAPODA, PORTUNIDAE IN AN AMAZONIAN ESTUARY.

    Directory of Open Access Journals (Sweden)

    Alessandra Batista Bentes

    2013-12-01

    Full Text Available For the first time specimens of Charybdis hellerii (Milne Edwards 1867, an Indo Pacific specie, were caught in Amazon estuary, Bragança, Pará, North of Brazil. Palavras-chave: Crustacea, Charybdis hellerii , Amazonian Estuary. DOI: http://dx.doi.org/10.18561/2179-5746/biotaamazonia.v3n3p181-184

  8. Investigation on Water Pollution of Four Rivers in Coastal Wetland of Yellow River Estuary

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    [Objective] The study aimed at analysing water pollution of four rivers in coastal wetland of Yellow River estuary. [Method] Taking four seriously polluted rivers (Guangli River, Shenxian Ditch, Tiao River and Chao River) in coastal wetland of Yellow River estuary as study objects, water samples were collected from the four rivers in May (dry period), August (wet period) and November (normal period) in 2009 and 2010 respectively, then pollution indices like nutritive salts, COD, chlorophyll-a, petroleum, et...

  9. Overview of trace metal contamination in the Scheldt estuary and effect of regulatory measures

    OpenAIRE

    Baeyens, W.F.J.; Leermakers, M; De Gieter, M.; Nguyen, H.L.; Parmentier, K.; Panutrakul, S.; Elskens, M.

    2005-01-01

    Seasonally, dissolved and particulate metal concentrations in the Scheldt estuary were assessed over a period of 4 years (1995–1998). High quality data were obtained following stringent analytical protocols for each step: sampling, sample treatment, sample storage and analysis. Of the 5 trace metals, Ni showed the most conservative behaviour, while Cd and Cu were clearly transferred from the particulate to the dissolved phase in the middle estuary. A substantial part of the particulate metals...

  10. Influence of benthic macrofauna community shifts on ecosystem functioning in shallow estuaries

    OpenAIRE

    Kristensen, Erik; Delefosse, Matthieu; Quintana, Cintia O.; Flindt, Mogens R.; Valdemarsen, Thomas

    2014-01-01

    We aim at identifying how ecosystem functioning in shallow estuaries is affected by rapid shifts in benthic fauna communities. We use the shallow estuary, Odense Fjord, Denmark, as a case study to test our hypotheses that (1) shifts in benthic fauna composition and species functional traits affect biogeochemical cycling with cascading effects on the ecological functioning, which may (2) modulate primary productivity in the overlying water column with feedbacks to the benthic system. Odense Fj...

  11. Developing a coupled analytical model for analyzing salt intrusion in alluvial estuaries

    Science.gov (United States)

    Savenije, H.; CAI, H.; Gisen, J.

    2013-12-01

    A predictive assessment technique to estimate the salt intrusion length and longitudinal salinity distribution in estuaries is important for policy makers and managers to maintain a healthy estuarine environment. In this study, the salt intrusion model of Savenije (2005, 2012) is applied and coupled to an explicit solution for tidal dynamics developed by Cai and Savenije (2013). The objective of the coupling is to reduce the number of calibration parameters, which subsequently strengthens the reliability of the salt intrusion model. Moreover, the fully analytical treatment allows assessing the effect of model forcing (i.e., tide and river discharge) and geometry adjustments (e.g., by dredging) on system performance. The coupled model has been applied to a wide range of estuaries, and the result shows that the correspondence between analytical estimations and observations is very good. As a result, the coupled model is a useful tool for decision makers to obtain first order estimates of salt intrusion in estuaries based on a minimum of information required. References Savenije, H.H.G. (2005), Salinity and Tides in Alluvial Estuaries, Elsevier. Savenije, H.H.G. (2012), Salinity and Tides in Alluvial Estuaries, completely revised 2nd edition, www.salinityandtides.com. Cai, H., and H. H. G. Savenije (2013), Asymptotic behavior of tidal damping in alluvial estuaries, Journal of Geophysical Research, submitted.

  12. Pollution in the estuary of the Baracoa river, La Habana, Cuba

    Directory of Open Access Journals (Sweden)

    Regla Duthit Somoza

    2011-04-01

    Full Text Available The environmental quality of the Baracoa river estuary was studied from the physic (temperature and salinity, chemic variables (dissolved oxygen, oxygen biochemical demand (DBO, oxygen chemical demand (DQO, nitrogen cycle, inorganic phosphorus and total phosphorus and the microbiological variables (total and thermotolerant coliforms and faecal streptococci. The samplings were made on February 2006, May and October 2007. Spatial distribution of the physical and chemical parameters measured suggests that the estuary is dominated by the marine conditions. The salinity and temperature analyses show that in general the characteristics of the estuary could be influenced by the contribution of the river basin drainage. In general, the concentrations of the measured parameters in the Baracoa river estuary, strongly suggest that this area is under influence of human activities on the river basin, due to the low levels of dissolved oxygen and an oxygen average deficit of -1.6 mg/L. nthropogenic actions in this estuary are mainly related to the emission of domestic and farming rejects without suitable treatment. This is visibly associated with the observed values of the total coliforms concentrations as well as the concentration of faecal streptococci, that surpassed reference values from the Cuban norm for water quality, following on bad or doubtful quality levels pointing out negatively measurements made next to the communication channel the estuary and the El Doctor lagoon.

  13. Spatial distribution and risk assessment of heavy metals in sediments of Shuangtaizi estuary, China

    International Nuclear Information System (INIS)

    Highlights: • Five heavy metals are analyzed in the sediments from Shuangtaizi estuary. • Particle size of the sediment effects the concentration of heavy metals. • Pb, Cu, Zn and Hg pose low ecological risks in the Shuangtaizi estuary. • Heavy metal pollution in Shuangtaizi estuary is mainly dominated by Cd. - Abstract: In order to evaluate the spatial distribution and potential ecological risk of Pb, Cu, Zn, Cd, and Hg, the surface sediments were collected from 18 sites in the Shuangtaizi estuary. The concentrations of Pb, Cu, Zn, Cd, and Hg were analyzed by atomic absorption spectrophotometry and atomic fluorescence spectrometry after digestion. The particle sizes of the sediments were analyzed using a laser diffraction particle size analyzer. The results show that the heavy metal contents in the sediments are observed in the following order: Zn (18.25–126.75 mg/kg) > Pb (4.38–9.65 mg/kg) > Cu (1.80–17.68 mg/kg) > Cd (0.241–0.764 mg/kg) > Hg (0.007–0.021 mg/kg). In comparison with the concentrations of heavy metals in other regions, the concentrations of Pb, Cu, and Zn in the Shuangtaizi estuary are generally low, and the Cd concentrations are close to those reported in other regions. Both the potential ecological risk index and the geoaccumulation index reveal that the heavy metal pollution in Shuangtaizi estuary is mainly dominated by Cd

  14. A classification of U.S. estuaries based on physical and hydrologic attributes

    Science.gov (United States)

    Engle, V.D.; Kurtz, J.C.; Smith, L.M.; Chancy, C.; Bourgeois, P.

    2007-01-01

    A classification of U.S. estuaries is presented based on estuarine characteristics that have been identified as important for quantifying stressor-response relationships in coastal systems. Estuaries within a class have similar physical and hydrologic characteristics and would be expected to demonstrate similar biological responses to stressor loads from the adjacent watersheds. Nine classes of estuaries were identified by applying cluster analysis to a database for 138 U.S. estuarine drainage areas. The database included physical measures of estuarine areas, depth and volume, as well as hydrologic parameters (i.e., tide height, tidal prism volume, freshwater inflow rates, salinity, and temperature). The ability of an estuary to dilute or flush pollutants can be estimated using physical and hydrologic properties such as volume, bathymetry, freshwater inflow and tidal exchange rates which influence residence time and affect pollutant loading rates. Thus, physical and hydrologic characteristics can be used to estimate the susceptibility of estuaries to pollutant effects. This classification of estuaries can be used by natural resource managers to describe and inventory coastal systems, understand stressor impacts, predict which systems are most sensitive to stressors, and manage and protect coastal resources. ?? Springer Science+Business Media B.V. 2007.

  15. Metabarcoding of benthic eukaryote communities predicts the ecological condition of estuaries

    International Nuclear Information System (INIS)

    DNA-derived measurements of biological composition have the potential to produce data covering all of life, and provide a tantalizing proposition for researchers and managers. We used metabarcoding to compare benthic eukaryote composition from five estuaries of varying condition. In contrast to traditional studies, we found biotic richness was greatest in the most disturbed estuary, with this being due to the large volume of extraneous material (i.e. run-off from aquaculture, agriculture and other catchment activities) being deposited in the system. In addition, we found strong correlations between composition and a number of environmental variables, including nutrients, pH and turbidity. A wide range of taxa responded to these environmental gradients, providing new insights into their sensitivities to natural and anthropogenic stressors. Metabarcoding has the capacity to bolster current monitoring techniques, enabling the decisions regarding ecological condition to be based on a more holistic view of biodiversity. - Highlights: • We used metabarcoding to examine the benthic eukaryote composition of five estuaries. • Biotic richness (based on MOTUs) was greater in the most impacted estuary. • Similarities among estuaries reflected their environmental condition. • Composition was strongly correlated with nutrients, turbidity and pH. • Metabarcoding can provide fast, comprehensive and ecologically informative data. - Using metabarcoding we were able discriminate benthos from five estuaries, and identify those taxa which responded negatively and positivity to the key environmental stressors

  16. Potential Impacts and Management Implications of Climate Change on Tampa Bay Estuary Critical Coastal Habitats

    Science.gov (United States)

    Sherwood, Edward T.; Greening, Holly S.

    2014-02-01

    The Tampa Bay estuary is a unique and valued ecosystem that currently thrives between subtropical and temperate climates along Florida's west-central coast. The watershed is considered urbanized (42 % lands developed); however, a suite of critical coastal habitats still persists. Current management efforts are focused toward restoring the historic balance of these habitat types to a benchmark 1950s period. We have modeled the anticipated changes to a suite of habitats within the Tampa Bay estuary using the sea level affecting marshes model under various sea level rise (SLR) scenarios. Modeled changes to the distribution and coverage of mangrove habitats within the estuary are expected to dominate the overall proportions of future critical coastal habitats. Modeled losses in salt marsh, salt barren, and coastal freshwater wetlands by 2100 will significantly affect the progress achieved in "Restoring the Balance" of these habitat types over recent periods. Future land management and acquisition priorities within the Tampa Bay estuary should consider the impending effects of both continued urbanization within the watershed and climate change. This requires the recognition that: (1) the Tampa Bay estuary is trending towards a mangrove-dominated system; (2) the current management paradigm of "Restoring the Balance" may no longer provide realistic, attainable goals; (3) restoration that creates habitat mosaics will prove more resilient in the future; and (4) establishing subtidal and upslope "refugia" may be a future strategy in this urbanized estuary to allow sensitive habitat types (e.g., seagrass and salt barren) to persist under anticipated climate change and SLR impacts.

  17. 2011 NATA - Risks and Annual Ambient Concentrations

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset includes the modeled annual ambient concentrations and risks at the census tract level for the 2011 National Air Toxics Assessment. All concentrations...

  18. Economía y medio ambiente

    Directory of Open Access Journals (Sweden)

    Ciro Alfonso Serna Mendoza

    2010-12-01

    Full Text Available En ciertos escenarios académicos, políticos, sociales y ambientales se declara que el modelo económico dominante o los conceptos que lo integran son responsables de que el bienestar económico implique malestar ecológico.Al partir de este supuesto, una forma de comprender las causas y de contribuir a la solución de la problemática ambiental es develar en qué consisten, en qué términos plantean la relación ombre-medio ambiente, las propuestas que incluyen la dimensión ambiental en el campo de la economía. Y si, al igual que las teorías ambientales, acuden a la ética como factor adecuado para disminuir las externalidades negativas generadas en el ambiente por la actividad económica.

  19. Dynamics of the Acartia genus (Calanoida: Copepoda) in a temperate shallow estuary (the Mondego estuary) on the western coast of Portugal

    OpenAIRE

    Azeiterio, Ulisses Miranda; Maques, Sónia Cotrim; Viera, Luís Miguel Russo; Pastorinho, Manuel Ramiro Dias; Ré, Pedro Alfaia Barcia; Pereira, Mário Jorge; Morgado, Fernando Manuel Raposo

    2005-01-01

    The purpose of this work was to review the dynamics of the Acartia species in the Mondego estuary (a temperate North-Atlantic shallow estuary in Western Portugal) in a genus integrated perspective. The Acartia genus is represented in the system by the species Acartia clausi and Acartia tonsa; the samples were taken between July 1999 and June 2000, with 63 and 125 µm mesh size nets, and between January 2003 and January 2004, with a 335 µm mesh size net, in the downstream and upstream areas of ...

  20. Role of different salt marsh plants on metal retention in an urban estuary (Lima estuary, NW Portugal)

    Science.gov (United States)

    Almeida, C. M. R.; Mucha, Ana P.; Teresa Vasconcelos, M.

    2011-01-01

    The aim of the present work was to understand the role different salt marsh plants on metal distribution and retention in the Lima River estuary (NW Portugal), which to our knowledge have not been ascertained in this area yet. The knowledge of these differences is an important requirement for the development of appropriate management strategies, and is poorly described for Eurosiberian estuaries, like the one selected. In addition it is important to understand the difference among introduced and native salt marsh plants. In this work, metal levels (Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) were surveyed (by atomic absorption spectrometry) in sediments from sites vegetated with Juncus maritimus, Spartina patens, Phragmites australis and Triglochin striata (rhizo-sediments), in non-vegetated sediments and in the different tissues of the plants (roots, rhizomes and aerial shoots). In general, rhizo-sediments had higher metal concentrations than non-vegetated sediments, a feature that seems common to sediments colonized by salt marsh plants of different estuarine areas. All plants concentrated metals, at least Cd, Cu and Zn (and Pb for T. striata) in their belowground structures ([ M] belowground tissues/[ M] non-vegetated sediment > 1). However, when considered per unit of salt marsh area, the different selected plants played a different role on sediment metal distribution and retention. Triglochin striata retained a significant metal burden in it belowground structures (root plus rhizomes) acting like a possible phyto-stabilizer, whereas P. australis had an higher metal burden in aboveground tissues acting as a possible phyto-extractor. As for J. maritimus and S. patens, metal burden distribution between above and belowground structures depended on the metal, with J. maritimus retaining, for instance, much more Cd and Cu in the aboveground than in the belowground structures. Therefore, the presence of invasive and exotic plants in some areas of the salt marsh may

  1. ANÁLISE DA QUALIDADE AMBIENTAL URBANA

    OpenAIRE

    Cíntia Minaki; Margarete Cristiane de Costa Trindade Amorim

    2012-01-01

    Con el intenso proceso de urbanización en Brasil, la calidad del medio ambiente se presenta como un factor extremadamente importante para evaluar las condiciones que los espacios urbanos pueden ofrecer a la población. En este sentido, este trabajo tuvo como objetivo verificar algunos de los indicadores ambientales urbanos en Guararapes, situada en el noroeste de Sao Paulo, con el fin de evaluar su calidad ambiental, con el objetivo de contribuir a sus estrategias de desarrollo. Los indicadore...

  2. Studies on length-weight relationship of Gerres filamentosus Cuvier from the estuaries of the southern Karnataka coast

    OpenAIRE

    Udupa, K.S.; Averel, M.; Raghavendra, C.H.; Bevinahalli, V.; Reddy, A; Kumarswamy, A.R.

    2003-01-01

    Random samples of Gerres filamentosus Cuvier from the Netravathi-Gurpur, Mulky, Kallayanapura, Mabukala and Kundapura estuaries of the southern Karnataka Coast were collected in the years 2000, 2001 and 2002, and length-weight relationships for each estuary were derived using multiple linear regression technique with one dummy variable. Hence, combined or sex-wise length-weight relationships were obtained after testing for homogeneity and isometric growth condition of fishes for each estuary ...

  3. Autotrophic and heterotrophic food sources of copepods in the Scheldt estuary as traced by stable C and N isotopes

    OpenAIRE

    L. De Brabandere

    2005-01-01

    Estuaries draining densely populated watersheds experience significant anthropogenic pressure and sustain large autotrophic and heterotrophic production owing to an increased input of nutrients and organic matter. Polluted estuaries are often net heterotrophic systems. Our objective was to study the relative contributionof autotrophic and heterotrophic food webs in sustaining the high productivity of pelagic estuarine ecosystems along the estuarine gradient of the Scheldt estuary. We concentr...

  4. Polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in sediments from the Mersey Estuary, U.K.

    OpenAIRE

    Vane, C.H.; Harrison, I; Kim, A W

    2007-01-01

    Sediments from the Mersey Estuary were analysed for polycylic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). Total PAH concentrations ranged from 626 to 3766 μg/kg and total PCB concentrations ranged from 36 to 1409 μg/kg. These concentrations are intermediate in comparison to other U.K estuaries with similar histories of industrialisation and urbanisation. The distribution of individual PAHs were consistent throughout the Mersey Estuary, this together with molecular indic...

  5. Ambient ionization mass spectrometry: A tutorial

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Min-Zong; Cheng, Sy-Chi; Cho, Yi-Tzu [Department of Chemistry, National Sun Yat-Sen University, Kaohsiung, Taiwan (China); Shiea, Jentaie, E-mail: jetea@fac.nsysu.edu.tw [Department of Chemistry, National Sun Yat-Sen University, Kaohsiung, Taiwan (China); Cancer Center, Kaohsiung Medical University, Kaohsiung, Taiwan (China)

    2011-09-19

    Highlights: {yields} Ambient ionization technique allows the direct analysis of sample surfaces with little or no sample pretreatment. {yields} We sort ambient ionization techniques into three main analytical strategies, direct ionization, direct desorption/ionization, and two-step ionization. {yields} The underlying principles of operation, ionization processes, detecting mass ranges, sensitivity, and representative applications of these techniques are described and compared. - Abstract: Ambient ionization is a set of mass spectrometric ionization techniques performed under ambient conditions that allows the direct analysis of sample surfaces with little or no sample pretreatment. Using combinations of different types of sample introduction systems and ionization methods, several novel techniques have been developed over the last few years with many applications (e.g., food safety screening; detection of pharmaceuticals and drug abuse; monitoring of environmental pollutants; detection of explosives for antiterrorism and forensics; characterization of biological compounds for proteomics and metabolomics; molecular imaging analysis; and monitoring chemical and biochemical reactions). Electrospray ionization and atmospheric pressure chemical ionization are the two main ionization principles most commonly used in ambient ionization mass spectrometry. This tutorial paper provides a review of the publications related to ambient ionization techniques. We describe and compare the underlying principles of operation, ionization processes, detecting mass ranges, sensitivity, and representative applications of these techniques.

  6. Decadal morphological evolution of the Yangtze Estuary in response to river input changes and estuarine engineering projects

    Science.gov (United States)

    Luan, Hua Long; Ding, Ping Xing; Wang, Zheng Bing; Ge, Jian Zhong; Yang, Shi Lun

    2016-07-01

    The Yangtze Estuary in China has been intensively influenced by human activities including altered river and sediment discharges in its catchment and local engineering projects in the estuary over the past half century. River sediment discharge has significantly decreased since the 1980s because of upstream dam construction and water-soil conservation. We analyzed bathymetric data from the Yangtze Estuary between 1958 and 2010 and divided the entire estuary into two sections: inner estuary and mouth bar area. The deposition and erosion pattern exhibited strong temporal and spatial variations. The inner estuary and mouth bar area underwent different changes. The inner estuary was altered from sedimentation to erosion primarily at an intermediate depth (5-15 m) along with river sediment decline. In contrast, the mouth bar area showed continued accretion throughout the study period. The frequent river floods during the 1990s and simultaneously decreasing river sediment probably induced the peak erosion of the inner estuary in 1986-1997. We conclude that both sediment discharge and river flood events played important roles in the decadal morphological evolution of the Yangtze Estuary. Regarding the dredged sediment, the highest net accretion rate occurred in the North Passage where jetties and groins were constructed to regulate the navigation channel in 1997-2010. In this period, the jetties induced enhanced deposition at the East Hengsha Mudflat and the high accretion rate within the mouth bar area was maintained. The impacts of estuarine engineering projects on morphological change extended beyond their sites.

  7. Dissolved inorganic carbon dynamics and CO2 atmospheric exchanges in the inner and outer Scheldt estuary

    OpenAIRE

    Borges, A. V.; Frankignoulle, M.

    2002-01-01

    Since 1992, the Chemical Oceanography Unit of the University of Liège has carried out on a regular basis field cruises in the Scheldt inner estuary and the river plume (outer estuary), during which were measured: pH, total alkalinity, dissolved inorganic carbon, partial pressure of CO2 (pCO2), dissolved oxygen and atmospheric flux of CO2. In the inner Scheldt estuary, pCO2 values in the upper estuary can be as high as 9000 ppm that is about 25 times the value of atmospheric equilibrium (pres...

  8. LA JUSTICIA AMBIENTAL EN EL ORDENAMIENTO JURÍDICO AMBIENTAL CHILENO

    OpenAIRE

    Dominique Hervé Espejo; Sebastián Rebolledo

    2013-01-01

    El presente trabajo desarrolla la noción de justicia ambiental y sus elementos configurativos. En virtud de aquel marco se revisan dos instituciones jurídicas del ordenamiento jurídico ambiental chileno, con el objeto de evaluar si en las normas que las consagran se incorporan o reflejan dichos elementos. Los instrumentos jurídicos analizados son la participación ciudadana en el Sistema de Evaluación de Impacto Ambiental y la Evaluación Ambiental Estratégica.

  9. O meio ambiente no meio ambiente da TV brasileira: percursos histórico-discursivos

    OpenAIRE

    Gomes, Ana Ângela Farias; Pereira, Claudio Luiz

    2010-01-01

    Este trabalho propõe uma investigação das interrelações entre a temática ambiental e a produção televisiva brasileira. O objetivo é traçar um panorama histórico das produções que tratyam especificamente da questão ambiental, e perceber como o meio ambiente vem sendo tematizado pela televisão ao longo do tempo. Ao mesmo tempo, pereceber as correlações entre as transformações/significados que a temática ambiental vai passando e as operações dircursivas implicadas.

  10. Biotecnologia Ambiental. Aplicacions biotecnològiques a la millora del medi ambient

    OpenAIRE

    Blanch i Gisbert, Anicet

    2010-01-01

    La biotecnología ambiental comprende el conjunto de actividades tecnológicas que facilitan la comprensión y la gestión de los sistemas biológicos en el medio ambiente, con el fin de proveer productos y servicios. Actualmente, la gestión del medio ambiente y de sus recursos naturales no se comprende si no se realiza de manera sostenible. Los avances científicos y tecnológicos le están permitiendo a la biotecnología ambiental, el desarrollo de nuevas herramientas y aplicaciones con los que resp...

  11. Towards New Ambient Light Systems: a Close Look at Existing Encodings of Ambient Light Systems

    Directory of Open Access Journals (Sweden)

    Andrii Matviienko

    2015-10-01

    Full Text Available Ambient systems provide information in the periphery of a user’s attention. Their aim is to present information as unobtrusively as possible to avoid interrupting primary tasks (e.g. writing or reading. In recent years, light has been used to create ambient systems to display information. Examples of ambient light systems range from simple notification systems such as displaying messages or calendar event reminders, to more complex systems such as focusing on conveying information regarding health activity tracking. However, for ambient light systems, there is a broad design space that lacks guidelines on when to make use of light displays and how to design them. In this paper we provide a systematic overview of existing ambient light systems over four identified information classes derived from 72 existing ambient light systems. The most prominent encoding parameters among the surveyed ambient light systems are color, brightness, and their combination. By analyzing existing ambient light systems, we provide a first step towards developing guidelines for designing future ambient light systems.

  12. The Ostracoda (Crustacea) of the Tina Menor estuary (Cantabria, southern Bay of Biscay): Distribution and ecology

    Science.gov (United States)

    Martínez-García, Blanca; Pascual, Ana; Rodríguez-Lázaro, Julio; Martín-Rubio, Maite; Rofes, Juan

    2013-10-01

    Recent ostracods from the Tina Menor estuary (northern Spain, southern Bay of Biscay) have been analysed. Twenty-five species have been identified for the first time, 20 with living individuals during the sampling period. The most abundant species are Leptocythere castanea, Leptocythere porcellanea, Loxoconcha elliptica, Cytherois fischeri, and Hemicytherura hoskini, Leptocythere psammophila and Semicytherura aff. angulata. These species are grouped into four assemblages defining different environments: muddy inner estuary with euryhaline species (L. elliptica); middle estuary with silty sand flats and low marsh environments (L. castanea, L. porcellanea and C. fischeri); sandy outer estuary with marine characteristics (H. hoskini, S. aff. angulata, Leptocythere baltica and L. psammophila); and littoral to inner shelf environment (Caudites calceolatus, H. hoskini and Callistocythere murrayi). In the middle estuary, L. castanea also delimits sandy-silty low marshes, and L. porcellanea and C. fischeri the vegetated ecosystems. Multivariate analyses with the samples and species (cluster Q-type and detrended and canonical correspondence analysis) confirm that ostracod distribution in the Tina Menor estuary is controlled by sediment grain size and by the distance to the mouth of the estuary (associated to salinity). The geographical height in relation with mean tide levels (and therefore with emersion periods) also plays an important role in distribution. The results of this study confirm ostracod validity as tide-level markers due to the presence of C. fischeri below the MHWNT (mean high water neap tide), whereas L. castanea and L. porcellanea are present between the MHWNT and MHW (mean high water) levels. Ostracods can also indicate environmental changes due to human-influenced processes. Abundant individuals of L. elliptica in some areas of the middle estuary evidence discharges of lower-salinity water from a nearby fish farm. Ostracods from the marine shelf reach the

  13. Tidal wetland conservation and restoration for flood mitigation in estuaries and deltas: examples and global potential

    Science.gov (United States)

    Temmerman, Stijn; Smolders, Sven; Stark, Jeroen; meire, patrick

    2014-05-01

    Low-lying and densely populated deltas and estuaries are world widely exposed to flood risks caused by storm surges. On the one hand, global change is increasing these flood risks through accelerating sea level rise and increasing storm intensity, but on the other hand, local-scale human impacts on deltas and estuaries are in many cases even more increasing the vulnerability to floods. Here we address the degradation and reclamation of tidal wetlands (i.e. salt marshes in the temperate zone and mangroves in the tropical zone) as a major source for increasing vulnerability to flooding of estuaries and deltas. Firstly, we present examples of flood mitigation by tidal wetland conservation and restoration, and secondly we explore the potentials and limitations for global application of this approach of ecosystem-based flood defense (see Temmerman et al. 2013). First, we use the Scheldt estuary (SW Netherlands and Belgium) as an example where historic wetland reclamation has importantly contributed to increasing flood risks, and where tidal marsh restoration on the previously reclaimed land is nowadays brought into large-scale practice as an essential part of the flood defense system. Based on data and hydrodynamic modelling, we show that large-scale historic marsh reclamation has largely reduced the water storage capacity of the estuary and has reduced the friction to propagating flood waves, resulting in an important landward increase of tidal and storm surge levels. Hydrodynamic model scenarios demonstrate how tidal and storm surge propagation through the estuary are affected by tidal marsh properties, including the surface area, elevation, vegetation and position of marshes along the estuary. We show that nowadays tidal wetland creation on previously reclaimed land is applied as an essential part of the flood defense system along the Scheldt estuary. Secondly, a global analysis is presented of the potential application of tidal wetlands in flood mitigation in

  14. Estuaries of southwest England: Salinity, suspended particulate matter, loss-on-ignition and morphology

    Science.gov (United States)

    Uncles, R. J.; Stephens, J. A.; Harris, C.

    2015-09-01

    Analyses of consistently measured survey data and published hydrological data for the estuaries of southwest England show that: (1) freshwater runoff and estuary length are strongly related to catchment area; (2) salt intrusion length is always greater than 74% of the estuary length during low runoff, spring-tide summer conditions and, on average, is more than 90% - there is a statistically significant relationship between salt intrusion length and tidal range (increased intrusion) and freshwater runoff (decreased intrusion); (3) salinity stratification is strongly, positively correlated with the Simmons' Ratio - a measure of the relative balance of freshwater- and tidally-induced current speeds; (4) residence times are strongly correlated with tidal range and tidal length and somewhat less strongly correlated with tidal prism - longer estuaries with smaller tides have longer residence times than shorter estuaries with stronger tides; (5) maximum surface suspended particulate matter (SPM) concentrations vary from 2 to 20,000 mg l-1; (6) maximum surface SPM concentrations are strongly related both to tidal range and tidal length and less strongly correlated with tidal prism - long, strongly tidal estuaries have greater concentrations; (7) loss-on-ignition (LOI) of SPM is strongly related to SPM concentration - low concentrations (less than a few mg l-1) typically have LOI > 50% and high concentrations (greater than a few hundred mg l-1) typically have LOI ∼ 10%; (8) LOI of the freshwater SPM is greater than that in the area of maximum estuarine SPM concentration, so that SPM within the high-turbidity reaches of southwest estuaries is significantly different from that entering the estuaries in their freshwater inflows; (9) an observed scaling relationship between estuary tidal length and a prescribed function both of depth at the mouth and tidal range is similar to that given by theoretical work (Prandle, 2004; Prandle et al., 2006), as is an observed scaling

  15. Análisis intra e interpoblacional de rasgos craneanos no métricos en aborígenes pre-hispánicos del actual territorio de Córdoba

    Directory of Open Access Journals (Sweden)

    Fabra, Mariana

    2003-01-01

    Full Text Available Recientes investigaciones de la arqueología de sociedades agroalfareras de la actual provincia de Córdoba señalan que existió un proceso de diversificación e intensificación diferencial que terminó definiendo modalidades regionales en los estilos de vida de dichas comunidades. Desde esta perspectiva, los desarrollos llevados a cabo en las sierras y la llanura extraserrana de las zonas centro y sur de Córdoba, difieren en algunos aspectos de aquellos implementados en la zona norte y, a su vez, estos dos de aquellos de los grupos de Traslasierra y San Luis. En este estudio se investigó, a través de 32 rasgos craneanos no métricos, si esta diversificación cultural se correspondió con diferencias biológicas regionales. Varias técnicas de análisis utilizadas (cluster análisis, correlación de matrices, autocorrelación espacial y multi-response permutation procedure, no pudieron identificar un patrón geográfico de variación, sugiriendo que no existió tal diferenciación biológica regional. Por otra parte, al confrontarse la serie Córdoba con otras de Argentina y Chile, extraídas de la literatura (González-José et al., Hum. Biol. 73:333-348, 2001, se puso de manifiesto una neta diferenciación entre Córdoba y las restantes series. El cluster analysis, a su vez, evidenció que Córdoba presenta una mayor similitud con los grupos de Patagonia y Tierra del Fuego, que con los del noroeste y noreste de Argentina

  16. Polychaete richness and abundance enhanced in anthropogenically modified estuaries despite high concentrations of toxic contaminants.

    Directory of Open Access Journals (Sweden)

    Katherine A Dafforn

    Full Text Available Ecological communities are increasingly exposed to multiple chemical and physical stressors, but distinguishing anthropogenic impacts from other environmental drivers remains challenging. Rarely are multiple stressors investigated in replicated studies over large spatial scales (>1000 kms or supported with manipulations that are necessary to interpret ecological patterns. We measured the composition of sediment infaunal communities in relation to anthropogenic and natural stressors at multiple sites within seven estuaries. We observed increases in the richness and abundance of polychaete worms in heavily modified estuaries with severe metal contamination, but no changes in the diversity or abundance of other taxa. Estuaries in which toxic contaminants were elevated also showed evidence of organic enrichment. We hypothesised that the observed response of polychaetes was not a 'positive' response to toxic contamination or a reduction in biotic competition, but due to high levels of nutrients in heavily modified estuaries driving productivity in the water column and enriching the sediment over large spatial scales. We deployed defaunated field-collected sediments from the surveyed estuaries in a small scale experiment, but observed no effects of sediment characteristics (toxic or enriching. Furthermore, invertebrate recruitment instead reflected the low diversity and abundance observed during field surveys of this relatively 'pristine' estuary. This suggests that differences observed in the survey are not a direct consequence of sediment characteristics (even severe metal contamination but are related to parameters that covary with estuary modification such as enhanced productivity from nutrient inputs and the diversity of the local species pool. This has implications for the interpretation of diversity measures in large-scale monitoring studies in which the observed patterns may be strongly influenced by many factors that covary with anthropogenic

  17. Vulnerability Assessments in Support of the Climate Ready Estuaries Program: A Novel Approach Using Expert Judgment, Volume I: Results for the San Francisco Estuary Partnership (Final Report)

    Science.gov (United States)

    As part of the Climate Ready Estuaries (CRE) program, the Global Change Research Program (GCRP) in the National Center for Environmental Assessment, Office of Research and Development at the U.S. Environmental Protection Agency has prepared this draft report exploring a new metho...

  18. Remote Sensing Technologies for Estuary Research and Management (Invited)

    Science.gov (United States)

    Hestir, E. L.; Ustin, S.; Khanna, S.; Botha, E.; Santos, M. J.; Anstee, J.; Greenberg, J. A.

    2013-12-01

    Estuarine ecosystems and their biogeochemical processes are extremely vulnerable to climate and environmental changes, and are threatened by sea level rise and upstream activities such as land use/land cover and hydrological changes. Despite the recognized threat to estuaries, most aspects of how change will affect estuaries are not well understood due to the poorly resolved understanding of the complex physical, chemical and biological processes and their interactions in estuarine systems. New and innovative remote sensing technologies such as high spectral resolution optical and thermal imagers and lidar, microwave radiometers and radar imagers enable measurements of key environmental parameters needed to establish baseline conditions and improve modeling efforts. Radar's sensitivity to water provides information about water height and velocity, channel geometry and wetland inundation. Water surface temperature and salinity and can be measured from microwave radiometry, and when combined with radar-derived information can provide information about estuarine hydrodynamics. Optical and thermal hyperspectral imagers provide information about sediment, plant and water chemistry including chlorophyll, dissolved organic matter and mineralogical composition. Lidar can measure bathymetry, microtopography and emergent plant structure. Plant functional types, wetland community distributions, turbidity, suspended and deposited sediments, dissolved organic matter, water column chlorophyll and phytoplankton functional types may be estimated from these measurements. Innovative deployment of advanced remote sensing technologies on airborne and submersible un-piloted platforms provides temporally and spatially continuous measurement in temporally dynamic and spatially complex tidal systems. Through biophysically-based retrievals, these technologies provide direct measurement of physical, biological and biogeochemical conditions that can be used as models to understand estuarine

  19. Sticky stuff! Seasonal flocculation in a hypertidal estuary

    Science.gov (United States)

    Todd, David; Souza, Alejandro; Jago, Colin

    2013-04-01

    Suspended particular matter (SPM) is a highly variable and important aspect of estuarine systems. It determines turbidity; impacting water quality, generates benthic fluff, modifies biogeochemical exchanges, and constrains primary productivity. Further, SPM carries biogeochemical components (e.g. carbon, nitrogen), deciding the fates of anthropogenic system inputs. Outside of the non-cohesive fraction (sand), little is known of the properties of estuarine SPM (i.e. sizes, densities, settling velocities) and how these impact sedimentation as most SPM is in the form of flocs (aggregates of dead and living organic matter, cohesive inorganic matter, and water) that are easily ruptured and/or may aggregate during sampling. As such, we lack reliable information on parameters such as settling velocities, particularly since floc properties change over tidal (suspension/advection), lunar (spring-neap cycle), and seasonal (storm resuspension and biological production) time scales. Turbulence is an important mediator of floc characteristics; low turbulence promotes collisions and flocculation, while high levels cause shear-induced rupture, literally tearing flocs apart. Because of this, turbulence parameterisation is key to understanding the relationship between turbulence and particle size. The results of an extensive field campaign in the Dee Estuary (N.W. United Kingdom) are presented, investigating the fates of SPM. Using data from a combination of acoustics, optics, moored deployments and CTD stations particle characteristics varied across tidal, spring-neap, and seasonal time-scales. This was due to seasonal changes in both river input and levels of biological activity. During winter, turbulence-mediated flocculation and breakup dominated, with particles coming together under quiescent conditions, and breaking up during high turbulence conditions. By contrast, stronger, more shear-resistant flocs were present during summer with increased yield strength providing

  20. Fishes and fisheries in tropical estuaries: The last 10 years

    Science.gov (United States)

    Blaber, S. J. M.

    2013-12-01

    Since 2002 there has been an increase in knowledge of many aspects of the biology and ecology of tropical estuarine fishes, as well as significant changes to many estuarine fisheries. Analyses of literature databases (2002-2012) show that: of the c. 600 relevant papers, 52% are primarily related to ecology, 11% to conservation, 11% to anthropogenic and pollution effects on fishes, 9% to fisheries, 7% to aquaculture, 4% to study techniques, and 1% each to fish larvae, effects of fishing, taxonomy, climate change, evolution and genetics. In terms of geographic spread 17% are from North America, 15% from south Asia, 14% from the Caribbean, 13% from Australasia, 12% from Africa and 9% each from South America and SE Asia. Research papers came from 50 countries of which the dominant were USA (15%), India (12%), Australia (11%) and Brazil (7%). Increasing numbers of studies in West Africa, SE and South Asia and South America have increased basic knowledge of the ecology of estuarine fish faunas. Increases in understanding relate to: roles of salinity, turbidity and habitat diversity; connectivity between habitats; water flow; ecological drivers of spatial variability; scale dependent variation; thermal tolerances; movement patterns; food webs; larval adaptations; and the viability of areas heavily impacted by human activities. New reviews both challenge and support different aspects of the estuarine dependence paradigm - still perhaps one of the main research issues - and the protective function of estuaries and mangroves for juvenile fishes has received attention in relation to e.g. predation risks and fisheries. There have also been significant advances in the use of guilds and biodiversity models. Fishing pressures have continued unabated in most tropical estuaries and are summarised and management issues discussed. Understanding of the relationships between fisheries production and mangroves has advanced and significant differences have emerged between Indo