Absorption coefficient of particulate matter on the south-west coast of Europe: a contribution to the validation of the MERIS-Medium Resolution Imaging Spectrometer sensor

Dissolved oxygen (DO) is one of the most important environmental variables of water quality, especially for marine life. Consequently, oxygen is one of the Chemical Quality Elements required for the implementation of European Union Water Framework Directive. This study uses the example of the Ria Formosa, a meso-tidal lagoon on the south coast of Portugal to demonstrate how monitoring of water quality for coastal waters must be well designed to identify symptoms of episodic hypoxia. New data from the western end of the Ria Formosa were compared to values in a database of historical data and in the published literature to identify long-term trends. The dissolved oxygen concentration values in the database and in the literature were generally higher than those found in this study, where episodic hypoxia was observed during the summer. Analysis of the database showed that the discrepancy was probably related with the time and the sites where the samples had been collected, rather than a long-term trend. The most problematic situations were within the inner lagoon near the city of Faro, where episodic hypoxia (<2 mg dm3 DO) occurred regularly in the early morning. These results emphasise the need for a balanced sampling strategy for oxygen monitoring which includes all periods of the day and night, as well as a representative range of sites throughout the lagoon. Such a strategy would provide adequate data to apply management measures to reduce the risk of more persistent hypoxia that would impact on the ecological, important natural resource. economic and leisure uses of this important natural resource.

Atlantic Area Eunis Habitats. Adding new habitat types from European Atlantic coast to the EUNIS Habitat Classification

Marine protection has been emphasized through global and European conventions which highlighted the need for the establishment of special areas of conservation. Classification and habitat mapping have been developed to enhance the assessment of marine environment and improve spatial and strategic planning of human activities and to help on the implementation of ecosystem based management. European Nature information System (EUNIS) is a comprehensive habitat classification system to facilitate the harmonised description and collection of habitat and biotopes that has been developed by the European Environment Agency (EEA) in collaboration with experts from institutions throughout Europe.

DNA damage in two bivalve species: Mytilus galloprovincialis and Ruditapes decussatus from the South coast of Portugal

Dissertação de mest., Estudos Marinhos e Costeiros, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2009

The fishery for Norway lobster off the portuguese coast: a biological and economic assessment

Dissertação de mest., Aquacultura e Pescas, Faculdade de Ciências do Mar e Ambiente, Universidade do Algarve, 2009

Water framework directive implementation: intercalibration exercise for biological quality elements: a case study for the south coast of Portugal

This work summarises the Intercalibration Exercise (IE) required for the Common Implementation Strategy of the Water Framework Directive (WFD; 2000/60/EC) that was carried out in Portugal, and applied to a coastal region. The WFD aims to achieve good ec ological status for all waters in the European Community by 2015. The Ecological Status of a water body is determined us ing a range of Hydromorphological and Physico-Chemical Quality Elements as well Biological Quality Elements (BQE ). In coastal waters, the Biological Elements include Phytoplankton, Other Aquatic Flora and Benthic Inverteb rate Fauna. Good cooperation with the other Member States allowed the IE to proceed without a complete da ta set, and Portugal was ab le to intercalibrate and harmonise methods within the North Ea st Atlantic Geographica l Intercalibration Group for most of the BQE. The appropriate metrics and corre sponding methods were agreed under the framework of the RECITAL (Reference Conditions and Intercalibra tion) project, funded by the Port uguese Water Institu te, INAG. Some preliminary sampling was undertaken, but not su fficient to establish the Reference Conditions. The study area was a coastal lagoon in the southern part of Portugal. The focus was on the Phytoplankton Quality Element, but other BQE were also taken into account. Two sampli ng stations in Ria Formosa coastal lagoon were considered in this exercise: Ramalhete a nd Ponte. The metrics adopted by the Intercalibration Exercise groups were applied enabli ng the classification for the two sta tions of Good/High Status for the majority of the BQE parameters.

Spiny lobster fishery on the southwest coast of Portugal: conciliating fisheries and conservation

Dissertação de mest., Aquacultura e Pescas (Pescas), Faculdade de Ciências e Tecnologia, Univ. do Algarve, 2011

Potential of fisheries restocking off the Algarve coast using aquaculture produced marine fish

Tese de dout., Ciências do Mar, da Terra e do Ambiente (Ecologia Marinha), Faculdade de Ciências e Tecnologia, Univ. do Algarve, 2012

Towards a hydrodynamic operational model of the Algarve coast and St. Vincent Cape

This study attempts to implement a hydrodynamic operational model which can ultimately be used for projecting oil spill dispersal patterns and also sewage, pollution and can also be used in wave forecasting. A two layer nested model was created using MOHID Water, which is powerful ocean modelling software. The first layer (father) is used to impose the boundary conditions for the second layer (son). This was repeated for two different wind dominant regimes, Easterly and Westerly winds respectively. A qualitative comparison was done between measured tidal data and the tidal output. Sea surface temperature was also qualitatively compared with the model’s results. The results from both simulations were analysed and compared to historical literature. The comparison was done at the surface layer, 100 metre depth and at 800m depth. In the surface layer the first simulation generated an upwelling event near Cape St. Vincent and within the Algarve. The second simulation generated a non-upwelling event within which the surface was flow reversed and the warm water mass was along the Algarve coastline and evening turning clockwise around Cape St. Vincent. At the 100 metre depth for both simulations, velocity vortexes were observed near Cape St. Vincent travelling northerly and southerly at various instances. At 800metre depth a strong oceanic flow was observed moving north westerly along the continental shelf.

Bycatch and discards of commercial trawl fisheries in the south coast of Portugal

Bycatch and discards are a cause of great concern in commercial world fisheries, with important ecological, economic and conservation implications. With the recent inclusion of a discards ban (‘landing obligation’), in the reform of the EU CFP, these issues have gained a tremendous attention from the economic, scientific, political and social point of view. Demersal trawl fisheries off the southern coast of Portugal capture an extraordinary diversity of species and generate considerable amounts of bycatch and discards. Bycatch includes commercially valuable target-species and bycatch species with low or no commercial value, but the great majority consists of unmarketable species, that are discarded. Bony fishes are dominant in bycatch and discards and the most discarded are of low or no commercial value. The reasons for discarding are fundamentally economic in nature (lack of commercial value) for bycatch species, and legal and administrative (legal minimum landing size) for commercially important species. The study of the reproductive biology of Galeus melastomus, discarded by crustacean trawls, suggests that a minimum landing size should be established for this species, and explains the importance of such a study in the assessment and management of fisheries. The discovery of a new species of the ray Neoraja iberica n. sp. contributes to the knowledge of the local marine biodiversity in Portuguese waters and of the global marine biodiversity. The three cases of abnormal hermaphroditism recorded in Etmopterus spinax, are the first cases known to date of hermaphroditism in this species. There is a need to find solutions to the problem of bycatch and discards of trawl fisheries in the Algarve coast. A combination of technical, regulatory and economic measures to minimize bycatch and reduce discards, before implementing a ‘landing obligation’, is thought to be the best approach to apply in the southern Portuguese multispecies trawl fisheries.

Spatial and temporal variation of commercially important bivalve species in the Algarve coast, Portugal

Dissertação de mestrado, Biologia Marinha, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2015

DNA extraction and RAPD markers to assess the genetic similarity among Gelidium sesquipedale (Rhodophyta) populations

A simple method developed for genomic DNA isolation from fungus was tested on the red alga, Gelidium sesquipedale (Clem.) Born et Thur., which is commercially exploited for its high sulfated polysaccharide (agar) content. This method is faster, cheaper, and less toxic than conventional phenol/chloroform methods. Random amplified polymorphic DNA (RAPD) amplifications were performed successfully without the necessity of purifying the DNA. RAPD markers were used to investigate the genetic similarity among three natural populations of G. sesquipedale from southern Portugal. Bulked-genomic DNA samples of 15 different individuals were made in each population. These can be conceived of as a sample of the population DNA. Of the 62 primers screened, 41 produced bands and 22 revealed polymorphisms. Genetic similarities among populations were high. Populations that are further away from each other have the lowest similarity coefficients, whereas the intermediate Ingrina population, located on the south coast, showed higher genetic similarity with the Odeceixe population located on the southwest coast, than with the Sao Rafael southern population. This suggests a higher genetic flow between Odeceixe and Ingrina or the result may be a founder effect in the sense that the species has propagated from the east coast to the south coast of Portugal. We conclude that the use of this isolation method with RAPD analysis is appropriate to characterize the genetic variability of this commercial species along its geographical distribution. Large sample sizes can be screened at a relatively low cost. Finding genetic markers for commercial populations of C. sesquipedale may be of industrial interest.

Marine photosynthetic organisms from the Portuguese coast as sources of antitumoural compounds

Dissertação de Mestrado, Ciências Biomédicas, Departamento de Ciências Biomédicas e Medicina, Universidade do Algarve, 2016

Age and growth, mortality and reproduction of the striped sea bream, Lithognathus mormyrus Linnaeus 1758, from the south coast of Portugal (Algarve)

The striped sea bream, Lithognathus mormyrus, used for this population dynamics study were obtained from longline catches and market sampling in the Algarve (south Portugal). The macroscopic analysis of the gonads and the gonad somatic index showed that the south Portuguese population of L. mormyrus spawns mainly between late spring and summer (June to August). The length at first maturity was similar for males and females and the value for both sexes combined was estimated to be 16.08 cm, corresponding to an age between 1 and 2 years. Fish age classes (0 to 13) were determined by reading growth rings on whole otoliths. Age determination was validated by marginal increment analysis. The estimated parameters of the von Bertalanffy growth equation were L infinity = 35.30 cm, K = 0.264 and t(0) = -0.809. Mortality rates were calculated for fish captured with longlines, and the estimated parameters were M = 0.356, Z = 0.622 and F = 0.266. From an Algarve fishery management perspective, these results suggest the need for an increase in the minimum landing size (from 15 to 17 cm), which should be beneficial for the sustainability and conservation of this species. The results also showed that fishing with longlines off the Algarve coast may allow for a sustainable use of the resource.

Diet of the blue marlin, Makaira nigricans, off the south coast of Portugal

The blue marlin, Makaira nigricans (Istiophoridae), is a large, top predator with a worldwide distribution whose feeding ecology is still unknown in the northeast Atlantic. The stomach contents of 24 Atlantic blue marlin, caught by the Big Game fishing fleet (between 2007 and 2010) off the south coast of Portugal, were studied. All marlin fed exclusively on pelagic fish, with a total of 180 prey items recorded, belonging to 6 identified species. The most important family in the blue marlin diet was Scombridae, representing 70% of the total prey items. Among the Scombridae, the chub mackerel, Scomber colias, was the most important prey species (47.9% by weight, 51.1% by number, 58.3% by frequency of occurrence). The length of prey found in the stomachs ranged from 136 to 727 mm in length, and a significant positive correlation was found between prey and blue marlin size. Our results suggest that in this geographical area (NE Atlantic) marlin feed on a small spectrum of species, with a preference for foraging on seamounts.

Reproductive aspects of the undulate ray, Raja undulata, from the south coast of Portugal

The maturity of the undulate ray, Raja undulata, one of the most important by-catch elasmobranch species captured in south Portugal, was studied for the first time. Females ranged in total length (TL) from 19.4 to 88.2 cm and males from 23.0 to 83.2 cm. The gonadosomatic index for females was higher during the winter, meaning that this species reproduces during this season. Females matured at significantly larger sizes and older ages than males, with 50% of the females mature at 76.2 cm TL at an age of 8.98 years while 50% maturity for males was achieved at 73.6 cm TL and 7.66 years. Females were mature at 86.3% of the maximum observed size and 69.1% of the maximum observed age while males matured at 88.5% of the maximum observed size and 63.8% of the maximum observed age, making this a very late maturing species, with important consequences in terms of fisheries management and conservation. (c) 2006 Elsevier B.V. All rights reserved.