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Ecological relationships between phytoplankton communities and different spatia...
Cabecinha, Edna; Van den Brink, Paul J.; Cabral, João Alexandre; Cortes, Rui; Lourenço, Martinho; Pardal, Miguel ÂngeloPhytoplankton communities are structured by factors acting over temporal and spatial scales. Identifying which factors are driving spatial patterns in aquatic communities is the central aim of ecology. In this study, data sets of phytoplankton communities and nvironmental data of two Portuguese servoirs types (lowland ‘‘riverine reservoirs’’ and higher altitude ‘‘artificial lake reservoirs’’) were used to dete...
Multi-scale approach using phytoplankton as a first step towards the definition...
Cabecinha, Edna; Cortes, Rui; Cabral, João Alexandre; Ferreira, Teresa; Lourenço, Martinho; Pardal, Miguel ÂngeloThe growing need to analyse the present state of ecosystems and predict their rate of change has triggered a demand to explore species environment relationships for assessing alterations under anthropogenic influence. The Water Framework Directive (WFD) requires the definition of different types of water bodies which are of relevance when assessing their ecological status. The main aim of this study was to defi...
Testing the Stochastic Dynamic Methodology (StDM) as a management tool in a sha...
Silva-Santos, Pedro; Pardal, Miguel Ângelo; Lopes, Ricardo Jorge; Múrias, Tiago; Cabral, João AlexandreA long-term monitoring program has been carried out since the early 1990s in the Mondego estuary, on Portugal's west coast, which is presently under heavy human pressure. In this shallow warm-temperate estuary, a significant macroalgal proliferation has been observed, which is a clear sign of nutrient enrichment. As a result of competition with algae, the extension of the seagrass meadows (mainly Zostera noltii...
A Stochastic Dynamic Methodology (SDM) to the modelling of trophic interactions...
Silva-Santos, Pedro; Pardal, Miguel Ângelo; Lopes, Ricardo Jorge; Múrias, Tiago; Cabral, João AlexandreIn the face of global change, declines in environmental quality are of increasing concern, especially in shallow coastal areas, densely populated and commonly affected by nutrient enrichment. The warm temperate Mondego estuary (Western Portugal), in common with many other shallow estuarine areas, is exhibiting increased macroalgal growth due to nutrient enrichment. The increase of macroalgal biomass and possibl...
Competition for feeding in waders: a case study in an estuary of south temperat...
Santos, Tiago Múrias; Cabral, João Alexandre; Lopes, Ricardo Jorge; Pardal, Miguel; Marques, João Carlos; Goss-Custard, JohnThe loss of feeding areas may pose a threat to many wintering waders because increased competition arising from reduced foraging space may force birds either to emigrate or to die. This has been demonstrated to occur in northwest European estuaries, but virtually no studies have been performed in the estuaries of southern Europe, where the loss of supratidal habitats (salines and saltmarshes), rather than inter...
Life history, population dynamics and production of eastern mosquitofish, Gambu...
Cabral, João Alexandre; Marques, João CarlosThe introduced population of Gambusia holbrooki from the rice fields of the lower Mondego River Valley, Portugal, was studied for 15 months, relating their life cycle and population dynamics with its production, in order to assess the role of the species in the energy flow and secondary production in this type of agro-ecosystem. Two main annual cohorts (1995 and 1996 cohorts) were identified. The females outnum...
The impact of macroalgal blooms on the use of the intertidal area and feeding b...
Cabral, João Alexandre; Pardal, Miguel Â.; Lopes, Ricardo J.; Múrias, Tiago; Marques, João CarlosThe present paper examined the possible impact of macroalgal blooms, among other influential factors, on prey abundance and availability to waders, assessing the consequences for feeding behaviour and for the specific patterns of use of the intertidal areas by these birds when macroalgal mats become dense and contiguous covering large areas of the Mondego estuary (west Portugal). Three representative microhabit...
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