The kelp beds of the Formigas Bank (NE Atlantic, Azores): predictive distribution modeling based on terrain variables
Pires de Carvalho, E.A. (2011). The kelp beds of the Formigas Bank (NE Atlantic, Azores): predictive distribution modeling based on terrain variables. MSc Thesis. University of the Azores: Punta Delgada. 18 pp.
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Available in | Author |
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Document type: Dissertation
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Keywords |
Distribution Flora > Weeds > Marine organisms > Seaweeds > Kelps ANE, Azores [Marine Regions] Marine/Coastal |
Author keywords |
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Abstract |
The Formigas Bank is a marine protected area located in the easternmost part of the Azores archipelago (northeast Atlantic). The seamount summit holds the sublittoral biotopes with the highest plant biomass recorded in the region, namely formed by dense Cystoseira and Laminaria beds. Phylariopsis specimens were first recorded for the Azores. A general biotope overview is presented for the deep infralittoral and circallittoral grounds of Bank based upon remote video surveys. The occurrences of Laminaria ochroleuca beds, a northern-most case of deep kelp and an exceptional occurrence in the Azores context, are then used to fit a predictive statistical model of local kelp distribution based on high resolution topographical covariates. A MAXENT model is obtained that shows high predictive success and identifies suitable habitat concentrated in a depth range of 50m to 80m, mostly west-facing slopes and flat surfaces. As a result, certain areas of the bank (Intermediate Reef and the western Dollabarat reef) are identified as the most suitable locales for the target species. In absence of detailed oceanographic models, terrain variables are shown to provide good covariates for modelling of kelp distribution. |
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