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Universitat de Girona. Departament d’Informà tica i Matemà tica Aplicada | |
Guerreiro, Catarina
Cachão, Mário De Stigter, H. Oliveira, A. Rodrigues, A. |
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Submarine canyons are deep and steep incisions on the continental margins. The physical forcingmechanisms linked with these marine systems, such as the enhancement of upwelling and bottomsediment resuspension, are expected to provide a nutrient source that will increase phytoplanktondensity (Hickey, 1995, Kampf,2006).Coccolithophores are the predominant phytoplanktonic group within the calcareousnannoplankton and their sensitivity to a variety of surface water environmental parameters makesthem important markers of oceanographic processes and proxies of sea surface water masses andtemperatures, productivity and past climate changes (e.g. Ziveri et al., 2004; Silva et al., 2008).In the present work we propose to test compositional analysis (Buccianti & Esposito, 2004;Pawlowsky-Glahn & Egozcue, 2006) as a tool to: a) achieve a clearer distinction betweenopportunistic coastal-neritic species (r-strategists) and typical oceanic species (k-strategists) in thecentral Portuguese margin, and b) to identify a coccolith assemblage that might reflect favorableenvironmental conditions found in the vicinity of the canyon that promotes the productivity ofcalcareous nannoplankton. Our main difficulty will be in distinguishing the ecological signal fromthe effects of other environmental factors mentioned before (i.e. advection, dissolution, bottomresuspension). One way to infer the species’ ecological inter-relationships is by determining speciesrelative percentages. The main concern is how the closure problem and the inconsistency ofpercentage determinations will affect our results. Compositional analysis was designed to providemore reliable and thus representative results, since the inference made on the coccolith assemblagefeatures from which the data are drawn is correctly performed from a theoretical point of view(Buccianti & Esposito, 2004). Here, we present the first insights from applying compositional dataanalysis to coccolith assemblages from 85 surface sediment samples collected from the centralPortuguese margin | |
http://hdl.handle.net/2072/273435 | |
eng | |
Universitat de Girona. Departament d’Informà tica i Matemà tica Aplicada | |
Tots els drets reservats | |
EstadÃstica matemà tica -- Congressos
Mathematical statistics -- Congresses Probabilitats -- Congressos Probabilities -- Congresses |
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Compositional Data Analysis as a Potential Tool to Study the (Paleo)ecology of Calcareous Nannoplankton from the Central Portuguese Submarine Canyons(W off Portugal) | |
info:eu-repo/semantics/conferenceObject | |
Recercat |