6 documents found, page 1 of 1
Functional resilience of PSII, vertical distribution and ecosystem-level estima...
Frankenbach, Silja; Azevedo, Andreina A.; Reis, Vanessa; Dias, Diana; Vaz, Leandro; Dias, João M.; Serôdio, JoãoMost studies on sediment-inhabiting microphytobenthos are based on the biomass present on the surface layers of intertidal flats. However, large amounts of microalgal biomass are known to exist below the surface. This study tested the role of subsurface microalgal biomass as a potential source of photosynthetically active cells for the biofilm on the surface. The resilience of buried cells was evaluated by expo...
Assessing the state of the lower level of the trophic web of a temperate lagoon...
Lopes, José Fortes; Vaz, Nuno; Vaz, Leandro; Ferreira, Juan A.; Dias, João MiguelThe main purpose of this study is to assess the state of the lower level of the trophic web of a temperate lagoon, the Ria de Aveiro (Portugal), in situations of light or nutrients limitation conditions, that may occur during extreme weather events (eventually associated to climate changes). The increase of the occurrence of extreme events (frequency, intensity and duration) is likely to globally intensify the ...
Impact of freshwater inflow on bacterial abundance and activity in the estuarin...
Santos, Luísa; Vaz, Leandro; Marcial Gomes, Newton C.; Vaz, Nuno; Dias, João Miguel; Cunha, Ângela; Almeida, AdelaideThe influence of freshwater flow on bacterial communities in the estuarine system Ria de Aveiro (Portugal) was investigated at two sites differently impacted by river inputs, representative of the marine and brackish water zones of the estuary. Sampling events were clustered based on hydrological features. The hydrodynamic was simulated with a Lagrangian model and related to microbiological parameters. Estuarin...
Development of an oil spill hazard scenarios database for risk assessment
Boer, Sérgio den; Azevedo, Alberto; Vaz, Leandro; Costa, Ricardo; Fortunato, André B.; Oliveira, Anabela; Tomás, Luís M.; Dias, João M.The occurrence of oil spills in coastal regions may have catastrophic consequences on the environment and severe socio-economic impacts. This work presents a new methodology to evaluate the risk associated with oil spills in coastal zones and estuaries, and illustrates its application in a coastal lagoon (Ria de Aveiro, Portugal). A ranked list of the hydrodynamic scenarios under which oil spills are most likel...
Sea level rise impact in residual circulation in Tagus estuary and Ria de Aveir...
Valentim, Juliana Marques; Vaz, Leandro; Vaz, Nuno; Silva, Helena; Duarte, Bernardo; Caçador, Isabel; Dias, João MiguelNowadays, there is a special concern about the possible impact of sea level rise in hydrodynamic patterns of coastal systems and its consequence in contingent ecosystems. In the present work, the effects of sea level rise in residual circulation are analyzed in two of the most important Portuguese coastal systems, Ria de Aveiro lagoon and Tagus estuary. The role of rivers inflow on residual circulation is also ...
Coastal wave regime influence on Ria de Aveiro inlet dynamics
Vaz, Leandro; Plecha, Sandra; Dias, João MiguelThe adjacent coastal zone of Ria de Aveiro lagoon is exposed to a highly energetic wave climate, with a yearly mean significant wave height of 2-2.5 m and wave periods of 9-11 s, corresponding to WNW to NNW swell. Consequently, it should be expected that the lagoon inlet hydrodynamic be dependent on the coupled forcing of tidal wave and wave regime. Thus, the main goal of this study is to assess the influence o...