Although many tropical stream consumers have large effects on resource quantity and quality, little is known about the relative importance of consumption versus bioturbation. We quantified egestion rates of freshwater shrimps (Atya spp. and Xiphocaris elongata) and mayflies (Leptophlebiidae) in two forest streams within the Luquillo Experimental Forest, Puerto Rico. Consumer body size was a strong predictor of egestion rates, with mass‐specific egestion rates declining with body size and per‐individual egestion rates increasing with body size. We used these egestion rates, together with published rates of epilithon removal by consumers and epilithon accrual by particle deposition and periphytic growth (i.e., with and without consumer access), to estimate the importance of consumption and bioturbation after storm events and during base‐flow conditions. Our estimates suggest that direct consumption of epilithon can only account for a minor proportion (< 5%) of material removed following storm events, with most removal likely resulting from bioturbation. During base‐flow conditions, we found that consumers (largely shrimps) may be capable of consuming a significant proportion of the material that would otherwise accrue on benthic substrata, but this result was limited to one high‐elevation site. Our study suggests that bioturbation is the dominant process that redistributes and entrains fine particles after storm events, and that a variable fraction of deposited and accrued benthic material may be consumed during base‐flow conditions. Our results underscore the importance of tropical stream animals in altering the benthic environment through both consumption and bioturbation, and suggest that consumer‐mediated material cycling is likely to be context dependent.

The stable carbon isotopic variability and the contributions of autochthonous (sediment microbial biomass, phytoplankton, and periphyton) and allochthonous (soil microbial biomass) sources available to the detritivorous fish Prochilodus lineatus were investigated in three environments of the floodplain of the Upper Paraná River. The isotopic composition of carbon sources and fish varied significantly among the studied environments. The autochthonous resources, represented by the phytoplankton, were the most assimilated by the species, followed by periphyton and sediment microbial biomass. The species used the sources differently in each environment. This study suggests that the inherent characteristics of this area, as well as the size of the watershed, the dry season, anthropogenic actions, and phytoplankton productivity, favor the use of autochthonous resources by the species studied. Therefore, studies in the floodplain should employ an eco-hydrological approach that quantifies the magnitude of energy subsidies, as well as an access route to consumers, knowledge about the selectivity of detritivorous species and the effects of different land uses.

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Environmental issues have triggered a complex relationship between society and nature. The role of environmental education is crucial to relate society, environment, biodiversity and sustainability. Current paper analyzes the concept of environmental education and sustainable development by post-graduate students in Education in Science and Mathematics of a Brazilian university. Qualitative research was undertaken in July 2014 by content analysis of the questionnaires and interviews (Lüdke e André, 1986) on the environmental theme. Current analysis showed that environmental education is intensely studied in primary education, albeit in a conservationist mode due to the lack of initial and continuous formation. Several participating students underlined that they had never taught environmental education in the primary school since they never had any contact with the discipline in their undergraduate course, a gap in initial formation. Although formation is urgent, it is greatly impaired and barriers have to be overcome. It is the case of one´s own formation, difficulties in interdisciplinary inclusion and the need of public policies in environmental education in higher education. Environmental education is increasingly being taught in all teaching levels for environmental sustainability, while professionals have improved their upgrading to contribute towards the long process in changes for a better life quality.Keywords: Sustainability. Teaching. Teachers´ Formation. Curricula and Higher Education. A PRÁTICA E A VISÃO DE PÓS-GRADUANDOS EM ENSINO DE CIÊNCIAS SOBRE EDUCAÇÃO AMBIENTAL E DESENVOLVIMENTO SUSTENTÁVEL NUMA UNIVERSIDADE BRASILEIRA Resumo: As questões ambientais têm desencadeado uma relação complexa entre a sociedade e a natureza. Diante dessa realidade, é fundamental o papel da educação ambiental a fim de relacionar sociedade, ambiente, biodiversidade e sustentabilidade. Assim, este trabalho teve como objetivo analisar a visão de educação ambiental e do desenvolvimento sustentável pelos alunos do curso de Pós-Graduação em Educação para a Ciência e a Matemática de uma universidade brasileira. A pesquisa qualitativa foi realizada em julho de 2014, por meio da análise de conteúdo dos questionários e entrevista (Lüdke e André, 1986) acerca da temática ambiental. O estudo demonstrou que a educação ambiental é bastante trabalhada no ensino básico, no entanto, de maneira conservacionista, o que ocorre devido à ausência da formação, tanto inicial como continuada. Vários participantes destacaram que nunca havia trabalhado educação ambiental no ensino básico, simplesmente porque nunca tiveram contado com a disciplina na graduação, ou seja, ausência da formação inicial. Embora a formação seja uma necessidade iminente, ainda é barrada por muitos obstáculos que necessitam ser vencidos, como é o caso da própria formação, a dificuldade da inclusão interdisciplinar e a necessidade de políticas públicas da educação ambiental no ensino superior. Concluiu-se que a educação ambiental, vem ganhando espaços em todos os níveis de ensino em busca da sustentabilidade ambiental, os profissionais, têm buscado melhorar sua autoformação, para que possam contribuir nesse longo processo de mudanças para uma vida melhor.Palavras-chave: Sustentabilidade. Docência. Formação de Professores. Curriculo e Ensino Superior LA PRÁCTICA Y EL CONCEPTO DE POSTGRADO EN EDUCACIÓN PARA LAS CIENCIAS EN EDUCACIÓN AMBIENTAL Y DESARROLLO SOSTENIBLE EN UNA UNIVERSIDAD BRASILEÑAResumen: Los temas ambientales han provocado una compleja relación entre la sociedad y la naturaleza. Ante esta realidad, el papel de la educación ambiental es fundamental para relacionar la sociedad, el medio ambiente, la biodiversidad y la sostenibilidad. Este trabajo tuvo como objetivo analizar la visión de la educación ambiental y el desarrollo sostenible por los estudiantes del curso de Postgrado en Educación para las Ciencias y las Matemáticas de una universidad brasileña. El estudio cualitativo se llevó a cabo en julio de 2014, mediante el análisis del contenido de los cuestionarios y entrevistas (Lüdke y André, 1986) acerca de los temas ambientales. El estudio mostró que la educación ambiental está bien trabajada en la educación básica, sin embargo, de uma manera conservada, lo que se produce debido a la falta de formación, tanto inicial como continuada. Varios participantes resaltaron que nunca habían trabajado la educación ambiental en la enseñanza primaria, simplemente porque nunca tuvieron contacto com esa matéria durante el pregrado, es decir, ausencia de formación inicial. A pesar de que la formación es una necesidad inminente, esta sigue siendo excluida por muchos obstáculos que deben ser superados, como la propia formación, la dificultad de inserción interdisciplinar  y la necesidad de políticas públicas de educación ambiental en la educación superior. Se concluyó que la educación ambiental ha ido ganando espacios en todos los niveles de educación en la búsqueda de la sostenibilidad del medio ambiente, los profesionales han tratado de mejorar su auto-aprendizaje para que puedan contribuir a este largo proceso de cambio de una vida mejor.Palabras clave: Sostenibilidad. Docencia. Formación docente. Programas de estudios y Educación Superior

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