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- Environmental literacy in biodiversity terms at the end of the compulsory school: case study in Amadora, PortugalPublication . Nicolau, Paula Bacelar; Nicolau, Leonor Bacelar; Galamba, J. M. M.; Azeiteiro, UlissesThis study assessed the contribution of formal environmental education, of the Portuguese national curricula, to student’s knowledge of biodiversity and related subjects, at the end of compulsory school. We also investigated the contribution of Alternative Courses on Education and Training to student’s environmental literacy, in terms of their knowledge of biodiversity and related subjects. The results of this study suggest that the formal environmental education of the national curricula and the alternative curricula did not significantly affect the environmental literacy of students, in terms of their knowledge of biodiversity and related subjects. A number of implications for Curriculum development and instructional practice are presented, and recommendations for further research are provided.
- Bacterioplankton dynamics in the Mondego estuary (Portugal)Publication . Nicolau, Paula Bacelar; Nicolau, Leonor Bacelar; Marques, J. C.; Morgado, Fernando; Azeiteiro, UlissesIn 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.
- Tide-induced variations in the bacterial community, and in the physical and chemical properties of the water column of the Mondego estuaryPublication . Nicolau, Paula Bacelar; Marques, João C.; Morgado, Fernando; Pastorinho, Ramires; Nicolau, Leonor Bacelar; Azeiteiro, UlissesThe bacterioplankton is a key component of the structure and function of aquatic ecosystems. Yet, present understanding of the controls on microbial abundance and activity only highlights their complexity. In estuaries, the problem is further complicated by the high variability of environmental properties (salinity, temperature, pH, organic loading and other factors). The present study investigates the dynamics of three main metabolic groups of planktonic bacteria involved in the cycling of organic matter (aerobic heterotrophic bacteria, sulphate-reducing bacteria, and nitrate-reducing bacteria), over one tidal cycle in the estuary of the Mondego. The association of various physical, chemical and biological parameters with the composition of the bacterial community was assessed by multivariate analysis in order to identify key factors controlling the composition and tidal dynamics of the bacterial communities in the Mondego estuary. Principal component analysis (PCA) identified the sources of variability for the bacterial communities in the estuary, as being, on one hand, the different dynamics in the two stations under study (Foz and Pranto) and, on the other hand, the flood and ebb tide fluxes, by their effects in the environmental parameters.