Study of the impact of the discharges of the Vila-Viçosa small hydroelectric development (Portugal) on the water quality and on the fish communities of the Ardena river

A study of the Vila-Viçosa small hydroelectric development, situated on the Ardena river (hydrographical basin of the river Douro, Portugal) was carried out for one year, with the purpose of evaluating the existence of differences in the fish communities found downstream and upstream of the development. A characterization of the system was made, bearing in mind morphological, hydrological and physical and chemical characteristics and studying the structure and dynamics of the fish communities. With the collected data on physical and chemical parameters a study of its space-time variation was made. Moreover, with the data relative to the fish communities a study of the space-time variation of some parameters was carried out. After the analysis of the data, it is possible to conclude that the Ardena river is a lotic system with water of good quality and that the functioning of the hydroelectric plant does not produce variations of the values of the parameters measured. The results obtained for the space-time variation of the fish community reveal some alterations in its distribution.Durante un año se ha estudiado la minicentral hidroeléctrica de Vila Viçosa en el río Ardena (cuenca del Duero, Portugal), con el objetivo de evaluar la existencia de diferencias en las comunidades de peces situadas abajo y arriba de la minicentral hidroeléctrica, caracterizando el sistema desde el punto de vista morfológico, hidrológico y físico-químico y estudiando la estructura y dinámica de las comunidades de peces. Con los datos relativos a los parámetros físico-químicos y los peces se ha hecho el estudio de la variación espacio-temporal. Además con los datos de los peces se ha estudiado la variación espacial y temporal de algunos parámetros. Después de analizados los datos, se puede decir que el río Ardena es un sistema lotico con agua de buena calidad y que el funcionamiento de la minicentral no provoca alteraciones de los valores encontrados. Los resultados de la variación espacial y temporal de la comunidad de peces reflejan alteraciones en su distribución

Personal exposure to particle concentration in a busy street

info:eu-repo/semantics/publishedVersio

Impact evaluation of the Vila Viçosa small hydroelectric power plant (Portugal) on the water quality and on the dynamics of the benthic macroinvertebrate communities of the Ardena river

Over a two-year period a study of the Vila Viçosa small hydroelectric development, located on the Ardena river (hydrographical basin of the Douro river, Portugal), was conducted, with the objective of evaluating the impact of its operation on the water quality and on the dynamics of the benthic macroinvertebrate community. A morphological, hydrologic and physico-chemical characterization of the system was done, an analysis of the benthic macroinvertebrate communities looking into their structure and dynamics, as well as ecological and physiological characteristics. With the physical and chemical data, a study of its spatial and temporal variation was performed. With the data related to the macroinvertebrate communities, an analysis of the spatial variation of some indexes and metrics and of the (non) similarity between the samples collected were done, bearing in mind the composition of the communities, through different techniques of multivariate analysis. After the analysis of the data, it is possible to say that the Ardena River is a lothic system, with good water quality, in which the working of the small hydroelectric power plant causes alterations on the macroinvertebrate community, due to the alteration of the "natural" hydrologic regime. The impact on the macroinvertebrate communities is lower upstream of the plant, where the flow is minimal throughout the whole year leading to a change in the structure of the community. Downstream of the plant, where the flow is extremely variable, there is an impoverishment of the communities, leading to the displacement of substrate and organisms.Durante dos años se ha estudiado la minicentral hidroeléctrica de Vila Viçosa en el río Ardena (cuenca del Duero, Portugal), con el objetivo de evaluar el impacto de su funcionamiento en la calidad del agua y en la dinámica de la comunidad de macroinvertebrados bentónicos, haciendo la caracterización del sistema desde el punto de vista morfológico, hidrológico y físico-químico y estudiando las comunidades de macroinvertebrados bentónicos, atendiendo a aspectos relacionados con su estructura, dinámica y características ecológicas y fisiológicas. Con los datos relativos a los parámetros físico-químicos se ha hecho el estudio de la variación espacio temporal; y con los datos relativos a la comunidad de macroinvertebrados, se ha hecho el estudio de la variación espacial de algunos índices y medidas y de la (dis)similaridad entre las muestras recogidas, teniendo en cuenta su composición, a través de diferentes técnicas de análisis multivariante. Después de analizados los datos, se puede decir que el río Ardena es un sistema lotico con agua de buena calidad y que el funcionamiento de la minicentral hidroeléctrica provoca modificaciones en la comunidad de macroinvertebrados bentónicos, resultado de las alteraciones de caudales. El impacto en las comunidades de macroinvertebrados es menor aguas arriba de las minicentrales, donde el caudal es mínimo todo el año provocando una modificación en la estructura de las comunidades. Aguas abajo de las minicentrales, donde el caudal es muy variable, hay un empobrecimiento de las comunidades, provocando el desplazamiento del substrato y de los organismos

Mini-garfagem: um novo metodo para a enxertia do mogno sul-americano (Swietenia macrophylla King).

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Uso de efluentes da carcinicultura de águas interiores na irrigação de arroz e melão.

bitstream/item/35386/1/Bd-028.pd

Out-of-phase oscillation between superfluid and thermal components for a trapped Bose condensate under oscillatory excitation

The vortex nucleation and the emergence of quantum turbulence induced by oscillating magnetic fields, introduced by Henn E A L, et al. 2009 (Phys. Rev. A 79, 043619) and Henn E A L, et al. 2009 (Phys. Rev. Lett. 103, 045301), left a few open questions concerning the basic mechanisms causing those interesting phenomena. Here, we report the experimental observation of the slosh dynamics of a magnetically trapped $^{87}$Rb Bose-Einstein condensate (BEC) under the influence of a time-varying magnetic field. We observed a clear relative displacement in between the condensed and the thermal fraction center-of-mass. We have identified this relative counter move as an out-of-phase oscillation mode, which is able to produce ripples on the condensed/thermal fractions interface. The out-of-phase mode can be included as a possible mechanism involved in the vortex nucleation and further evolution when excited by time dependent magnetic fields.Comment: 5 pages, 5 figures, 25 reference

Generalized coordinates on the phase space of Yang-Mills theory

We study the suitability of complex Wilson loop variables as (generalized) coordinates on the physical phase space of $SU(2)$-Yang-Mills theory. To this end, we construct a natural one-to-one map from the physical phase space of the Yang-Mills theory with compact gauge group $G$ to a subspace of the physical configuration space of the complex G^\C-Yang-Mills theory. Together with a recent result by Ashtekar and Lewandowski this implies that the complex Wilson loop variables form a complete set of generalized coordinates on the physical phase space of $SU(2)$-Yang-Mills theory. They also form a generalized canonical loop algebra. Implications for both general relativity and gauge theory are discussed.Comment: TeX, 11pp, revised version (minor clarifications added, Comment after (2.9) inserted); to appear in Class. Quant. Grav

Parasitofauna de Hoplias malabaricus Bloch, 1794 (Erythrinidae) do Estado do Amapá, Amazônia oriental, Norte do Brasil.

ENBRAPOA

Spectral optical monitoring of the double peaked emission line AGN Arp 102B: II. Variability of the broad line properties

We investigate a long-term (26 years, from 1987 to 2013) variability in the broad spectral line properties of the radio galaxy Arp 102B, an active galaxy with broad double-peaked emission lines. We use observations presented in Paper I (Shapovalova et al. 2013) in the period from 1987 to 2011, and a new set of observations performed in 2012--2013. To explore the BLR geometry, and clarify some contradictions about the nature of the BLR in Arp 102B we explore variations in the H$\alpha$ and H$\beta$ line parameters during the monitored period. We fit the broad lines with three broad Gaussian functions finding the positions and intensities of the blue and red peaks in H$\alpha$ and H$\beta$. Additionally we fit averaged line profiles with the disc model. We find that the broad line profiles are double-peaked and have not been changed significantly in shapes, beside an additional small peak that, from time to time can be seen in the blue part of the H$\alpha$ line. The positions of the blue and red peaks { have not changed significantly during the monitored period. The H$\beta$ line is broader than H$\alpha$ line in the monitored period. The disc model is able to reproduce the H$\beta$ and H$\alpha$ broad line profiles, however, observed variability in the line parameters are not in a good agreement with the emission disc hypothesis. It seems that the BLR of Arp 102B has a disc-like geometry, but the role of an outflow can also play an important role in observed variation of the broad line properties.Comment: 17 pages, Accepted for publication in A&