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- EUNIS habitat's thresholds for the Western coast of the Iberian Peninsula — A Portuguese case studyPublication . Monteiro, Pedro; Bentes, L.; Oliveira, Frederico; Afonso, Carlos; Rangel, Mafalda; Gonçalves, J. M. S.The European Nature Information System (EUNIS) has been implemented for the establishment of a marine European habitats inventory. Its hierarchical classification is defined and relies on environmental variables which primarily constrain biological communities (e.g. substrate types, sea energy level, depth and light penetration). The EUNIS habitat classification scheme relies on thresholds (e.g. fraction of light and energy) which are based on expert judgment or on the empirical analysis of the above environmental data. The present paper proposes to establish and validate an appropriate threshold for energy classes (high, moderate and low) and for subtidal biological zonation (infralittoral and circalittoral) suitable for EUNIS habitat classification of the Western Iberian coast. Kineticwave-induced energy and the fraction of photosynthetically available light exerted on the marine bottom were respectively assigned to the presence of kelp (Saccorhiza polyschides, Laminaria hyperborea and Laminaria ochroleuca) and seaweed species in general. Both data were statistically described, ordered fromthe largest to the smallest and percentile analyseswere independently performed. The threshold between infralittoral and circalittoral was based on the first quartile while the ‘moderate energy’ class was established between the 12.5 and 87.5 percentiles. To avoid data dependence on sampling locations and assess the confidence interval a bootstrap technique was applied. According to this analysis,more than 75% of seaweeds are present at locations where more than 3.65% of the surface light reaches the sea bottom. The range of energy levels estimated using S. polyschides data, indicate that on the IberianWest coast the ‘moderate energy’ areas are between 0.00303 and 0.04385 N/m2 of wave-induced energy. The lack of agreement between different studies in different regions of Europe suggests the need for more standardization in the future. However, the obtained thresholds in the present study will be very useful in the near future to implement and establish the Iberian EUNIS habitats inventory.
- Deployment characterization of a floatable tidal energy converter on a tidal channel, Ria Formosa, PortugalPublication . Pacheco, André; G-Gorbeña, Eduardo; Plomaritis, Haris; Garel, Erwan; Gonçalves, J. M. S.; Bentes, L.; Monteiro, P.; Afonso, Carlos; Oliveira, Frederico; Soares, C.; Zabel, F.; Sequeira, ClaudiaThis paper presents the results of a pilot experiment with an existing tidal energy converter (TEC), Evopod 1 kW floatable prototype, in a real test case scenario (Faro Channel, Ria Formosa, Portugal). A baseline marine geophysical, hydrodynamic and ecological study based on the experience collected on the test site is presented. The collected data was used to validate a hydro-morphodynamic model, allowing the selection of the installation area based on both operational and environmental constraints. Operational results related to the description of power generation capacity, energy capture area and proportion of energy flux are presented and discussed, including the failures occurring during the experimental setup. The data is now available to the scientific community and to TEC industry developers, enhancing the operational knowledge of TEC technology concerning efficiency, environmental effects, and interactions (i.e. device/environment). The results can be used by developers on the licensing process, on overcoming the commercial deployment barriers, on offering extra assurance and confidence to investors, who traditionally have seen environmental concerns as a barrier, and on providing the foundations whereupon similar deployment areas can be considered around the world for marine tidal energy extraction.