DOP - Dissertações de Mestrado / Master Thesis
Permanent URI for this collection
Dissertação de Mestrado. Nível intermédio de uma dissertação (4 ou 5 anos de estudo). Contempla também dissertações do período pré-Bolonha para graus académicos que agora são reconhecidos como grau de mestre.
(Aceite; Publicado; Actualizado).
Browse
Browsing DOP - Dissertações de Mestrado / Master Thesis by advisor "Gomes, Telmo Alexandre Fernandes Morato"
Now showing 1 - 2 of 2
Results Per Page
Sort Options
- Deep-Sea ecosystem model of the Condor seamountPublication . Sousa, Janaína Bon; Gomes, Telmo Alexandre Fernandes MoratoSeamounts play an important role in the status of food webs and biodiversity in the open ocean. These habitats are now subject to an intensive exploitation and it is urgent to apply an ecosystem perspective towards the development of sustainable fisheries. Ecosystem models offer scope to understand the interactions between fisheries, exploited species and the ecosystem that supports them, enabling impact assessments of human activities on the marine environment. This study describes the construction and input data of an Ecopath with Ecosim model for the Condor seamount ecosystem, located in the Azorean archipelago (NE Atlantic). The model comprises 23 functional groups, including plankton, invertebrates, fishes, marine mammals and seabirds. The fisheries component consists on the regional fleet, with an emphasis on demersal fisheries. This model can serve as a basis for future Ecosim and Ecospace simulations of the effect of fishing on Condor seamount or on other seamounts around the Azorean islands.
- Habitat predictive modelling of demersal fish species in the AzoresPublication . Parra, Hugo Alexandre Esteves; Gomes, Telmo Alexandre Fernandes Morato; Menezes, Gui Manuel Machado; Tempera, FernandoSpecies distribution modelling of the marine environment has been extensively used to assess species–environment relationships to predict fish spatial distributions accurately. In this study we explored the application of two distinct modelling techniques, maximum entropy model (MaxEnt) and generalized linear models (GLMs) for predicting the potential distribution in the Azores economic exclusive zone (EEZ) of four economically important demersal fish species: blackbelly rosefish, Helicolenus dactylopterus dactylopterus, forkbeard, Phycis phycis, wreckfish, Polyprion americanus and offshore rockfish, Pontinus kuhlii. Models were constructed based on 13 years of fish presence/absence data derived from bottom longline surveys performed in the study area combined with high resolution (300 m) topographic and biogeochemical habitat seafloor variables. The most important predictors were depth and slope followed by sediment type, oxygen saturation and salinity, with relative contributions being similar among species. GLMs provided ‘outstanding’ model predictions (AUC>0.9) for two of the four fish species while MaxEnt provided ‘excellent’ model predictions (AUC=0.8–0.9) for three of four species. The level of agreement between observed and predicted presence/absence sites for both modelling techniques was ‘moderate’ (K=0.4–0.6) for three of the four species with P. americanus models presenting the lowest level of agreement (K<0.1). For the scope of this study, both modelling approaches presented here were determined to produce viable presence/absence maps which represent a snap–shot of the potential distributions of the investigated species. This information provides a better description of demersal fish spatial ecology and can be of a great deal of interest for future fisheries management and conservation planning.