title: Urban vs. extra-urban environments: scales of variation of intertidal benthic assemblages in north Portugal.
abstract: Littoral areas are subject to severe and increasing pressures resulting from human activities occurring along or next to the coast. In this study, patterns of variability in the structure of rocky intertidal benthic assemblages and in the abundance of individual taxa were compared between locations close to the coastal cities of Porto and Vila Nova de Gaia (north Portugal) and reference locations far from it in much less urbanized conditions over a temporal scale of fourteen months and multiple spatial scales. Present findings indicated that assemblages were more heterogeneously distributed in the urban than in the extra-urban condition. The total number of taxa and several individual taxa displayed, in general, this same pattern of variability. This could be interpreted as the beginning of a habitat deterioration process with largely unpredictable consequences. The adopted sampling design supports the need for simultaneously including a range of temporal and spatial scales when evaluating responses of coastal marine biodiversity to anthropogenic disturbances.
authors.affiliation: Estação Litoral da Aguda, Rua Alfredo Dias, Praia da Aguda, 4410-475 Arcozelo/VNG, Portugal; CIMAR/CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal. Electronic address: zpoliveira@gmail.com.
authors.forename: J P
authors.initials: JP
authors.lastname: Oliveira
authors.affiliation: CIMAR/CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal; Department of Biology, Faculty of Sciences, University of Porto, Rua do Campo Alegre s/n, 4169-007 Porto, Portugal.
authors.forename: I
authors.initials: I
authors.lastname: Sousa-Pinto
authors.affiliation: Estação Litoral da Aguda, Rua Alfredo Dias, Praia da Aguda, 4410-475 Arcozelo/VNG, Portugal; CIMAR/CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal; ICBAS - Institute of Biomedical Sciences Abel Salazar, Rua Jorge Viterbo de Ferreira 228, 4050-313 Porto, Portugal.
authors.forename: G M
authors.initials: GM
authors.lastname: Weber
authors.affiliation: CIMAR/CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal.
authors.forename: I
authors.initials: I
authors.lastname: Bertocci
mesh_terms: D059001:Aquatic Organisms / Q000502:physiology*; D044822:Biodiversity; D017753:Ecosystem; D004784:Environmental Monitoring; D011174:Portugal; D012623:Seawater; D014507:Urbanization
keywords: Benthic ecology; Beta diversity; Hierarchical sampling; Portugal; Rocky intertidal; Spatial and temporal heterogeneity; Urbanization