8,903 research outputs found
Linking fish-based biological indicators with hydrological dynamics in a Mediterranean river: Relevance for environmental flow regimes
The relationship between flow dynamics and biological communities becomes especially relevant in Mediterranean rivers. Given their natural variability and growing anthropogenic pressures, their low sections are subjected to multiple impacts. The definition of ecohydrological relationships in Mediterranean rivers may constitute a useful management tool. Historically, fishes were the first group used to assess community-level ecological quality, and different indices and metrics have been proposed. However, up to date many of these indicators have showed to be insensitive to flow regime changes or hydrological alteration. There is therefore a need to deepen into the ecohydrological relationships between such indicators and flow regimes in Mediterranean (and other) rivers. This study presents an analysis of the relationship between interannual flow regimes in the lower section of the Ebro River, defined using a set of daily and hourly hydrological indices, and ecological quality based on fish community, assessed through indices designed to fulfill the Water Framework Directive (WFD) in Europe: the Indices of Biotic Integrity in Catalan rivers (IBICAT2010 and IBICAT2b) and the new European Fish Index (EFI+). In order to identify spatiotemporal patterns, hydrological indices were computed using time periods of different amplitude and ecological quality was obtained in different transects along the river section, even within the same water units or ‘water masses’ (subdivisions of surface waters to fulfill the WFD in Spain). Our results showed that IBICAT2010 was the most correlated with hydrological indices, followed by IBICAT2b and EFI+. The latter showed an almost null correlation with hydrological indices, which may be due to issues associated with the sampling technique, the definition of transects and because it does not uses stream typologies. Correlations among some hydrological and biological indices were observed, with temporal and spatial patterns. On one hand, daily hydrological indices showed relationship with ecological quality when they were computed using between 9 and 36 months of flow records (previous to the sampling date) whereas subdaily indices responded better to periods between 3 and 9 months of records. On the other hand, some sampling transects showed clearer relationships than others, even within the same water mass, which suggests an influence of hydromorphological variability on the obtained ecological quality scores.info:eu-repo/semantics/acceptedVersio
Aguas residuales y plantas acu?ticas "Berros". Un estudio de construcci?n de conceptos en el aula con estudiantes del grado cuarto y quinto de la instituci?n educativa Normal Superior Fabio Lozano Torrijos de Falan, Tolima
79 P?ginasRecurso Electr?nicoAguas Residuales y Plantas Acu?ticas ?Berros? es resultado del trabajo liderado desde el Proyecto Construcci?n conceptual en el aula de clases dentro del proyecto Aula Viva del programa de Licenciatura para la Educaci?n B?sica en Ciencias Naturales y Educaci?n Ambiental de la Universidad del Tolima.
La investigaci?n es un aporte a la construcci?n conceptual en la escuela, a trav?sde la realizaci?n de las estrategias pedag?gicas y did?cticas, se construyen losconceptos de manera colaborativa o individual. El trabajo investigativo buscadar respuesta al siguiente interrogante: ?C?mo reconocer el concepto de plantas acu?ticas especialmente los berros y su utilizaci?n en la descontaminaci?n de aguas residuales con los estudiantes del grado cuarto y quinto de la sede santa filomena de la I.E. Normal superior de Falan ? Tolima?
El trabajo responde a la investigaci?n de tipo formativo, centrada en el estudiantey el docente; la aprehensi?n de conceptos surge de la experimentaci?n a trav?s delas siguientes etapas: ?Las plantas acu?ticas una maravilla en el agua? resultado deuna salida pedag?gica al medio en el que viven; una segunda etapa ?El berro m?gico ?oportunidad de caracterizar, analizar, experimentar y generar conceptos con las plantas y ?El triunfo acu?tico digital? en el que se incorporan las TIC al aulade clase mediante la construcci?n de una catilla digital.
El territorio de observaci?n fue en la Sede Santa Filomena de la Instituci?n Educativa Normal Superior Fabio Lozano Torrijos del municipio de Falan Tolima, con 12 estudiantes del grado cuarto y quinto de b?sica primaria, en edades que oscilan entre los 8 a 12 a?os, durante el a?o 2013.ABSTRACT. The paper residual waters and aquatic plants ?CRESS? is a partial result of the research liderated from the Project conceptual construction in the classroom in the Project living classroom in the program of Degree in Basic Education with emphasis in Natural Sciences of the Tolima?s University.
The research is a contribution at the conceptual construction in the school through pedagogical and didactic strategies; the concepts are building in a collaborative and individual way. The research searches to answer the following question: How can we recognize the aquatic plants concept specially the Cress and its uses in the residual waters decontamination with the students of fourth and fifth grade in Santa Filomena?s School in the I. E. Normal Superior in Falan Tolima?
The paper answers at formative research; it is centered in the student and the teacher; the conceptual apprehension are originated from the experimentation through the following steps: ?The aquatic plants a wonder in the water? that is the result of a field trip at the environment; a second step ?The magic cress? that is an opportunity for characterize, analyze, experiment and generate concepts with the water and ?The aquatic digital triumph? where we incorporated the I.C.T at the classroom through the building of a digital magazine.
The observation territory was the Santa Filomena School in the I. E. Normal Superior Fabio Lozano Torrijos in de Falan Tolima, It has 12 students in fourth to fifth grade, their ages are from 8 to 12 years old, It was in the year 2013.INTRODUCCI?N 12
1. LA AVENTURA DEL CONOCIMIENTO 15
1.1 FORMULACI?N DEL PROBLEMA 15
1.2 OBJETIVOS 16
1.2.1 Objetivos Generales 16
1.2.2 Objetivos Espec?ficos 16
1.3JUSTIFICACI?N 17
2. LA ESTRATEGIA DEL SABER 19
2.1. TIPO DE INVESTIGACI?N 19
2.2. T?CNICAS PARA LA RECOLECCI?N DE INFORMACI?N 21
2.3. POBLACION Y MUESTRA 24
2.4. ETAPAS DE LA INVESTIGACI?N 27
2.4.1. Las plantas acu?ticas una maravilla 27
2.4.2. El berro m?gico 27
2.4.3. El triunfo acu?tico digital 28
3. CONSTRUCCI?N CONCEPTUAL EN EL AULA DE CLASES 29
3.1. VISI?N LEGAL SOBRE LOS PROCESOS EDUCATIVOS 29
3.2. APROXIMACI?N PSICOL?GICA 31
3.3. PROCESO DE APRENDIZAJE 33
3.4. LUGAR PARA APREHENDER 39
3.5. TIC PARA LA EDUCACI?N 43
3.6. AMBIENTE Y NATURALEZA 49
4. PUERTAS ABIERTAS AL APRENDIZAJE 51
5. CONCLUSIONES 66
RECOMENDACIONES 67
REFERENCIAS BIBLIOGR?FICAS 6
Bilayer infiltration system combines benefits from both coarse and fine sands promoting nutrient accumulation in sediments and increasing removal rates
Infiltration systems are treatment technologies based on water percolation through porous media where biogeochemical processes take place. Grain size distribution (GSD) acts as a driver of these processes and their rates and influences nutrient accumulation in sediments. Coarse sands inhibit anaerobic reactions such as denitrification and could constrain nutrient accumulation in sediments due to smaller specific surface area. Alternatively, fine sands provide higher nutrient accumulation but need a larger area available to treat the same volume of water; furthermore, they are more susceptible to bioclogging. Combining both sand sizes in a bilayer system would allow infiltrating a greater volume of water and the occurrence of aerobic/anaerobic processes. We studied the performance of a bilayer coarse-fine system compared to a monolayer fine one - by triplicate - in an outdoor infiltration experiment to close the C-N-P cycles simultaneously in terms of mass balances. Our results confirm that the bilayer coarse-fine GSD promotes nutrient removal by physical adsorption and biological assimilation in sediments, and further it enhances biogeochemical process rates (2-fold higher than the monolayer system). Overall, the bilayer coarse-fine system allows treating a larger volume of water per surface unit achieving similar removal efficiencies as the fine system. This document is the unedited Author’s version of a Submitted Work that was subsequently accepted for publication in Environmental science and technology
FUSE Observations of the Magellanic Bridge Gas toward Two Early-Type Stars: Molecules, Physical Conditions, and Relative Abundance
We discuss FUSE observations of two early-type stars, DI1388 and DGIK975, in
the low density and low metallicity gas of Magellanic Bridge (MB). Toward
DI1388, the FUSE observations show molecular hydrogen, O VI, and numerous other
atomic or ionic transitions in absorption, implying the presence of multiple
gas phases in a complex arrangement. The relative abundance pattern in the MB
is attributed to varying degrees of depletion onto dust similar to that of halo
clouds. The N/O ratio is near solar, much higher than N/O in damped Ly-alpha
systems, implying subsequent stellar processing to explain the origin of
nitrogen in the MB. The diffuse molecular cloud in this direction has a low
column density and low molecular fraction. H2 is observed in both the
Magellanic Stream and the MB, yet massive stars form only in the MB, implying
significantly different physical processes between them. In the MB some of the
H2 could have been pulled out from the SMC via tidal interaction, but some also
could have formed in situ in dense clouds where star formation might have taken
place. Toward DGIK975, the presence of neutral, weakly and highly ionized
species suggest that this sight line has also several complex gas phases. The
highly ionized species of O VI, C IV, and Si IV toward both stars have very
broad features, indicating that multiple components of hot gas at different
velocities are present. Several sources (a combination of turbulent mixing
layer, conductive heating, and cooling flows) may be contributing to the
production of the highly ionized gas in the MB. Finally, this study has
confirmed previous results that the high-velocity cloud HVC 291.5-41.2+80 is
mainly ionized composed of weakly and highly ions. The high ion ratios are
consistent with a radiatively cooling gas in a fountain flow model.Comment: Accepted for publication in the ApJ (October 10, 2002). Added
reference (Gibson et al. 2000
Occupational Risk Prevention in the Management of Companies in the Electricity Sector. The case of Galicia (Spain)
30-34The present work aims at analysing the awareness and prevention in the management system of companies in the electricity sector, in order to detect the main shortcomings, seeking to improve in terms of occupational risk prevention. After collecting and analyzing a sample of 180 surveys, numerous shortcomings have been detected in the sector of electrical and telecommunications installations in Galicia (Spain), including the lack of established goals and objectives in preventive matters or the absence of the use of preventive modalities
A teachers’ orientation approach to understand the university teacher-student relationship
This research intends to advance the understanding of the university teacher-student relationship in the context of teachers’ market orientation with the aim to improve students’ performance. Thus, the study is articulated on three axes: the students’ performance approach, the relationship among diverse aspects of teachers, and, fi nally, the effect of these aspects on students’ performance. The results gained from a sample of 45 teachers and 932 students show that teachers’ student orientation infl uences perceived learning and student satisfaction. Other interesting results are also attained that lead to certain conclusions and implications.Este estudio pretende avanzar en la comprensión de la relación entre el profesor y el estudiante universitario con el objetivo de mejorar el rendimiento de los estudiantes. Se articula sobre tres ejes: el enfoque de rendimiento del estudiante, la relación entre diversos aspectos del profesor y, fi nalmente, el efecto de estos aspectos sobre el rendimiento del estudiante. Los resultados obtenidos de una muestra de 45 profesores y 932 estudiantes muestran que la orientación al estudiante por parte del profesor afecta al aprendizaje percibido y a la satisfacción del estudiante. Se alcanzan otros interesantes resultados que permiten establecer ciertas conclusiones e implicaciones
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