Estimates of Particulate Organic Carbon Flowing from the Pelagic Environment to the Benthos through Sponge Assemblages

Despite the importance of trophic interactions between organisms, and the relationship between primary production and benthic diversity, there have been few studies that have quantified the carbon flow from pelagic to benthic environments as a result of the assemblage level activity of suspension-feeding organisms. In this study, we examine the feeding activity of seven common sponge species from the Taputeranga marine reserve on the south coast of Wellington in New Zealand. We analysed the diet composition, feeding efficiency, pumping rates, and the number of food particles (specifically picoplanktonic prokaryotic cells) retained by sponges. We used this information, combined with abundance estimates of the sponges and estimations of the total amount of food available to sponges in a known volume of water (89,821 m3), to estimate: (1) particulate organic carbon (POC) fluxes through sponges as a result of their suspension-feeding activities on picoplankton; and (2) the proportion of the available POC from picoplankton that sponges consume. The most POC acquired by the sponges was from non-photosynthetic bacterial cells (ranging from 0.09 to 4.69 g C d−1 with varying sponge percentage cover from 0.5 to 5%), followed by Prochlorococcus (0.07 to 3.47 g C d−1) and then Synechococcus (0.05 to 2.34 g C d−1) cells. Depending on sponge abundance, the amount of POC that sponges consumed as a proportion of the total POC available was 0.2–12.1% for Bac, 0.4–21.3% for Prochlo, and 0.3–15.8% for Synecho. The flux of POC for the whole sponge assemblage, based on the consumption of prokaryotic picoplankton, ranged from 0.07–3.50 g C m2 d−1. This study is the first to estimate the contribution of a sponge assemblage (rather than focusing on individual sponge species) to POC flow from three groups of picoplankton in a temperate rocky reef through the feeding activity of sponges and demonstrates the importance of sponges to energy flow in rocky reef environments

VIII Encuentro de Docentes e Investigadores en Historia del Diseño, la Arquitectura y la Ciudad

Acta de congresoLa conmemoración de los cien años de la Reforma Universitaria de 1918 se presentó como una ocasión propicia para debatir el rol de la historia, la teoría y la crítica en la formación y en la práctica profesional de diseñadores, arquitectos y urbanistas. En ese marco el VIII Encuentro de Docentes e Investigadores en Historia del Diseño, la Arquitectura y la Ciudad constituyó un espacio de intercambio y reflexión cuya realización ha sido posible gracias a la colaboración entre Facultades de Arquitectura, Urbanismo y Diseño de la Universidad Nacional y la Facultad de Arquitectura de la Universidad Católica de Córdoba, contando además con la activa participación de mayoría de las Facultades, Centros e Institutos de Historia de la Arquitectura del país y la región. Orientado en su convocatoria tanto a docentes como a estudiantes de Arquitectura y Diseño Industrial de todos los niveles de la FAUD-UNC promovió el debate de ideas a partir de experiencias concretas en instancias tales como mesas temáticas de carácter interdisciplinario, que adoptaron la modalidad de presentación de ponencias, entre otras actividades. En el ámbito de VIII Encuentro, desarrollado en la sede Ciudad Universitaria de Córdoba, se desplegaron numerosas posiciones sobre la enseñanza, la investigación y la formación en historia, teoría y crítica del diseño, la arquitectura y la ciudad; sumándose el aporte realizado a través de sus respectivas conferencias de Ana Clarisa Agüero, Bibiana Cicutti, Fernando Aliata y Alberto Petrina. El conjunto de ponencias que se publican en este Repositorio de la UNC son el resultado de dos intensas jornadas de exposiciones, cuyos contenidos han posibilitado actualizar viejos dilemas y promover nuevos debates. El evento recibió el apoyo de las autoridades de la FAUD-UNC, en especial de la Secretaría de Investigación y de la Biblioteca de nuestra casa, como así también de la Facultad de Arquitectura de la UCC; va para todos ellos un especial agradecimiento

New estimation of private returns to higher professional education and training

In this paper, a cost-benefit type of analysis is used to determine the rate of returns to education for the specific case of professional education and training (PET), differentiating for the two types of PET education offered in Switzerland. In contrast to the Mincer-type of analysis, the cost-benefits calculations allow to include the costs of education, direct and indirect, and the risk of unemployment. The net benefits of the PET program are estimated by calculating the discounted wages over the lifecycle, minus lost wages in case of unemployment, and the costs of education for individuals. These net benefits are then compared to those of individuals with upper secondary vocational education. The Swiss Labor Force Survey (SLFS) 1996-2009 is used in this analysis. The panel structure of the SLFS allows to calculate lower bounds of the wage gains, correcting thereby the endogeneity of the educational choice. The results show that, independent of the amount of financial support, individuals completing a PET have significant net-wage gains. (DIPF/Orig.

Are the elderly a threat to educational expenditures?

Empirical research has given cause to fear that the demographic ageing in industrialized countries is likely to exert a negative impact on educational spending. Although this line of research shows in many cases a negative correlation between the proportions of the elderly and educational expenditures, a causal link is difficult to prove. To further analyse this topic, this paper uses a unique and representative survey of Swiss voters of all age groups. Results show that elderly people have a clear tendency to be less willing to spend money on education. They rather prefer to spend public resources on health and social security than on education. Furthermore the paper shows that although the elderly are more conservative and in general less inclined to pay for expenditures in the public sector as a whole, there is still an age effect on the willingness to pay for education after controlling for these factors.Public finance Education finance Demographics Survey Switzerland

What happened to the PISA 2000 participants five years later?

The transition from school-to-work has been a burning issue in most countries for the last decades. So far research on this topic has not been conclusive, and it is still not clear whether transition problems are just individual, linked to the type of education followed at uppersecondary level or just a prolongation of problems arising from poor school performance during compulsory education. This paper uses a unique Swiss longitudinal data-set, which includes information on PISA 2000 scores and the pathways chosen after completing compulsory school. Descriptive results show that students in vocational training, who obtained lower PISA results, are signicantly more likely to be in an inadequate employment situation two years after nishing vocational training. Further analysis shows, however, that it is the type of vocational training followed at upper-secondary level that is decisive for the success in the transition. Nevertheless, individual PISA scores have an indirect impact on the transition results, as they are an important factor explaining which pupils are more likely to get into an intellectually demanding vocational training and which ones are not

PISA et la transition vers le marché du travail

Dieser Beitrag untersucht den Einfluss der PISA-Lesekompetenzen am Ende der obligatorischen Schulzeit auf einen erfolgreichen Arbeitsmarkteintritt. Die deskriptiven Ergebnisse zeigen, dass Jugendliche mit tiefen PISA-Messwerten ein signifikant erhöhtes Risiko aufweisen, zwei Jahre nach Berufsbildungsabschluss inadäquat beschaftigt zu sein. Weiter gehende Analysen verdeutlichen hingegen, dass es der Typ beruflicher Grundbildung ist, welcher for eine erfolgreiche Arbeitsmarkttransition entscheidend ist. Nichtsdestotrotz haben PISA-Scores einen indirekten Einfluss auf den Übergang ins Erwerbsleben, da sie ein wichtiger Erklarungsfaktor dafür sind, wer Zugang zu Berufsbildungsgängen mit hohen Anforderungen bekommt.Cette contribution examine l'influence des compétences de lecture PISA en fin de scolarité obligatoire sur la manière dont les jeunes négocient leur entrée sur le marché du travail. Les résultats descriptifi montrent que les jeunes qui ont de mauvais résultats PISA, présentent un risque nettement plus élevé de se retrouver deux ans après l'obtention du diplôme de formation professionnelle dans un emploi inadéquat. Une analyse plus approfondie montre cependant que la réussite est étroitement liée au type de formation professionnelle de base. Malgré cela, les résultats PISA ont une influence indirecte sur le passage à la vie professionnelle, dans la mesure où ils expliquent qui a accès aux parcours de formation professionnelle à exigences élevées

PISA and the Transition into the Labour Market

This paper uses unique Swiss longitudinal data that include information on Programme for International Student Assessment (PISA) 2000 scores and the pathways chosen after completing compulsory school. Descriptive results show that students in vocational training, who obtained lower PISA results, are significantly more likely to be in an inadequate employment situation 2 years after finishing vocational training. Further analysis shows, however, that it is the type of vocational training pursued at upper secondary level that is decisive for a successful transition. Nevertheless, individual PISA scores have an indirect impact on the transition results, as they are an important factor explaining which pupils are more likely to get into an intellectually demanding vocational training and which ones are not. Copyright 2009 The Authors. Journal compilation 2009 CEIS, Fondazione Giacomo Brodolini and Blackwell Publishing Ltd..