Papers by Nuno Vaz Álvaro
Universidade dos A p e s , Dept. de Biologia, PT-9500 Ponla Delgada (&ores), Portugal. 'Esco~a Su... more Universidade dos A p e s , Dept. de Biologia, PT-9500 Ponla Delgada (&ores), Portugal. 'Esco~a Superior de Tecnologia da SaGde, PT-4000 Poito. Partugal. Neste trabarho estudou-se prirnacialmente os valores craniomdtricos do coelho selvagem Oryctolagw cunicuhs L., 1758, da Ilha Terceirn, seguindo-se o estudo da sua densidade e dinlmica populacional. Cornpararam-se estatisticamente os resultados obtidos da amostragem desta Ilha corn os obtidos nas amostragens de outms tRs Ilhas do Grupo Central-S. Jorge, Pico e Faial.
International Symposium FloraMac2012. Colegio dos Jesuitas, Funchal, Madeira, 5-8 de Setembro.
International Symposium FloraMac2012. Colegio dos Jesuitas, Funchal, Madeira, 5-8 de Setembro.
Chemosphere, Mar 1, 2020
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
International Meeting on Marine Resources 2010. Peniche, Portugal, 16-17 de Novembro
International Symposium FloraMac 2010. Ponta Delgada, Açores, 23-25 de Setembro de 2010
34th European Marine Biology Symposium. Ponta Delgada, Açores, 13-17 de Setembro de 1999
Estuarine Coastal and Shelf Science, Feb 1, 2013
During summer 2008 and spring 2009, surface oceanographic surveys were carried out around three i... more During summer 2008 and spring 2009, surface oceanographic surveys were carried out around three islands of the Azores archipelago (Terceira, São Miguel and Santa Maria) to assess the phytoplankton distribution and associated physico-chemical processes. The Azores archipelago is a major feature in the biogeochemical North Atlantic Subtropical Gyre (NAST) province although its influence on the productivity of the surrounding ocean is poorly known. Surface phytoplankton was studied by microscopy and HPLC (High Precision Liquid Chromatography). The mean values for biomass proxy Chlorophyll a (Chla) ranged from 0.04 to 0.55 mg L À1 (Chla maximum ¼ 0.86 mg L À1) and coccolithophores were the most abundant group, followed by small flagellates, Cyanobacteria, diatoms and dinoflagellates being the least abundant group. The distribution of phytoplankton and coccolithophore species in particular presented seasonal differences and was consistent with the nearshore influence of warm subtropical waters from the south Azores current and colder subpolar waters from the north. The satellite-derived circulation patterns showed southward cold water intrusions off Terceira and northward warm water intrusions off Santa Maria. The warmer waters signal was confirmed by the subtropical coccolithophore assemblage, being Discosphaera tubifera a constant presence under these conditions. The regions of enhanced biomass, either resulting from northern cooler waters or from island induced processes, were characterized by the presence of Emiliania huxleyi. Diatoms and dinoflagellates indicated coastal and regional processes of nutrient enrichment and areas of physical stability, respectively.
Marine Pollution Bulletin, 2017
Differences in the structure and functioning of intensively urbanized vs. less human-affected sys... more Differences in the structure and functioning of intensively urbanized vs. less human-affected systems are reported, but such evidence is available for a much larger extent in terrestrial than in marine systems. We examined the hypotheses that (i) urbanization was associated to different patterns of variation of intertidal assemblages between urban and extra-urban environments; (ii) such patterns were consistent across mainland and insular systems, spatial scales from 10s cm to 100s km, and a three months period. Several trends emerged: (i) a more homogeneous distribution of most algal groups in the urban compared to the extra-urban condition and the opposite pattern of most invertebrates; (ii) smaller/larger variances of most organisms where these were, respectively, less/more abundant; (iii) largest variability of most response variables at small scale; (iv) no facilitation of invasive species by urbanization and larger cover of canopy-forming algae in the insular extra-urban condition. Present findings confirm the acknowledged notion that future management strategies will require to include representative assemblages and their relevant scales of variation associated to urbanization gradients on both the mainland and the islands.
Aquatic Invasions, 2019
Human activities are contributing to the homogenization of the world's biota by transporting thou... more Human activities are contributing to the homogenization of the world's biota by transporting thousands of species to areas outside their native range. Some of these species can lead to profound changes in the structure and function of natural ecosystems in areas where they are introduced, with dramatic economic and ecological impacts. The red alga Asparagopsis armata is considered an invasive species in Europe, but can be particularly abundant in the Azores (NE Atlantic), where there is virtually no information on its ecology. Here, we investigate the patterns of spatial distribution and impacts of A. armata in the Azores, as a first step to understand its potential spread. Adopting a hierarchical design, we surveyed the distribution of A. armata, and associated assemblages, at a range of spatial scales (from islands (10s of km apart), locations (kms apart), sites (10s of m apart) to quadrats (m apart)). Results showed that the abundance of A. armata varied significantly among locations and that there was substantial variability in its abundance among islands, locations and quadrats and little variability among sites. At the scale of locations, the abundance of A. armata did not correlate with any of our predictor variables (sea urchin density, Latitude, Longitude and sea temperature). However, at the quadrat scale, there was a significant and negative correlation between the abundance of A. armata and diversity of associated macrophytes, as well as, with the abundance of the conspecific A. taxiformis and the abundance of most of the remainder macroalgal groups. The potential role of biotic and abiotic factors in generating the observed patterns is discussed. This study further highlights the suitability of the analytical tools used here to examine patterns of distribution over a range of spatial scales and its applicability in the field of aquatic invasions.
The establishment and management of Marine Protected Areas (MPAs) require information on the mari... more The establishment and management of Marine Protected Areas (MPAs) require information on the marine benthic habitats and associated biota. MPAs in the Azores have been mostly established with poor knowledge of the sea bottom substrate and the associated biological communities. This lack of information may create managing difficulties. This is particularly true for Vila Franca do Campo Islet, the published studies being exclusively on the biota and merely descriptive. In the present study a characterization of the Islet subtidal biota is provided, complemented with information on the Islet biotope. No significant differences were found between the Islet and the Island nearby. The new biotope is characteristic of vertical seawalls and is likely to be present in other locations throughout the archipelago.
42nd European Marine Biology Symposium. Kiel, Alemanha, 27-31 de Agosto de 2007
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Papers by Nuno Vaz Álvaro