Southwestern Coast Of Portugal Research Articles

Consolidation of Soft Sandstones Used in Historical Constructions. Application to a Case Study

ABSTRACT The use of natural stone consolidators in historic buildings, when applicable, makes it possible to improve the internal cohesion of the stones and restore or improve the original mechanical properties that the material once had. This paper describes the in situ and lab tests on the characterization of a very porous natural sandstone used in the construction of a late 17th century Fort, located near Sines, on the south-western coast of Portugal, classified as a Property of Public Interest. Given its location, in a most aggressive environment, this construction has suffered severe degradation. A representative number of samples (stones) were taken from the somewhat degraded surrounding structures attached to the Fort. Part of these samples were subjected to a consolidation process using a commercial ethyl silicate and then submitted to physical and mechanical tests with the purpose of evaluating the consolidation action. The remaining (unconsolidated) part of the samples were subjected to the same characterization tests, for comparison. The work carried out showed the effectiveness of the consolidation treatment in reinforcing the mechanical strength of the sandstone.

Socio-economic, operational and technical characterisation of the harvesting of gooseneck barnacle (Pollicipes pollicipes) in SW Portugal: Insights towards fishery co-management

The present study characterised the socio-economic, operational and technical aspects of harvesting the gooseneck barnacle (Pollicipes pollicipes) along the southwestern coast of Portugal. For this purpose, face-to-face interviews were conducted with commercial harvesters of the two most representative fishery associations (covering 51% licensed harvesters) in the area of the Parque Natural do Sudoeste Alentejano e Costa Vicentina. Based on traditional ecological knowledge, this study confirmed the local importance, ancestral character and family traditions of this activity, which constitutes the exclusive occupation of nearly half of the interviewed harvesters and an important source for household incomes. In addition, data was also gathered on preferential fishing zones, harvesting effort and duration, daily catches and selling prices. The main concerns, problems and difficulties experienced in this activity relate to the excessive number of recreational harvesters, creating problems at the levels of exploitation, commercialisation, management and inspection. The study further confirms the rising interest and involvement of the commercial harvesters in enhancing the competences of the local fishery associations. In particular, local harvesters want to encourage the development of a co-management system comprising spatial-temporal measures to avoid conflicts of use over space and resources, as well as innovative marketing strategies to improve the recognition, value and traceability of the shellfish. Overall, the information gathered is most valuable for adopting an alternative approach based on the cooperation and co-responsibility at local and regional levels, involving the stakeholders in the proposal of management measures adapted to the specificities of this area, activity and resource.

Changes in trophic ecology of fish assemblages after no take Marine Protected Area designation in the southwestern coast of Portugal

Changes in fish assemblage structure caused by human activities, such as fishing, can alter trophic relations in fish assemblages. In this context, Marine Protected Areas (MPA) are efficient tools for habitat recovery and ideal environments for evaluating changes on the trophic structure resulting from human activities. The present work targeted fish assemblages from two no-take MPAs from the northern half of South Alentejo and Costa Vicentina Marine Park, established in 2011. Previous works reported positive effects on local fish assemblages after no-take MPA designation, and it is therefore important to further study its impact on local fish assemblages, especially concerning trophic interactions. Local fish assemblages were sampled (summer 2011, winter 2012, summer 2013 and winter 2013) using trammel nets. Diets were characterized and digestive tract contents of the 10 most abundant fish species were compared between the no take MPAs (treatment) and adjacent areas (controls), and changes evaluated as a function of time since protection. Results revealed significant differences between the diets of fish from protected and non protected areas, with crabs being the preferential prey in both protected and control areas but being more ingested outside the no-take areas. However, these differences were evident since the beginning of the study. Fish assemblages from the northern area presented significantly larger niche breadth and significantly increasing with time. This way, the main effects of no-take MPA implementation were directly visible on the niche breadth but did not directly impact the diet composition of the sampled fish assemblages, contributing however to reinforce the already naturally existent differences. This work provides important information regarding the effect of changes in the fish assemblage caused by MPA designation on the trophic ecology of fish.

Changes in fish assemblage structure after implementation of Marine Protected Areas in the south western coast of Portugal

Marine Protected Areas (MPAs) are increasingly being recommended as management tools for biodiversity conservation and fisheries. With the purpose of protecting the region's biodiversity and prevent the over exploitation of marine resources, in February 2011 the no-take MPAs of Ilha do Pessegueiro and Cabo Sardão were implemented within the “Parque Natural do Sudoeste Alentejano e Costa Vicentina “(PNSACV) Marine Park, south western coast of Portugal. As such, commercial and recreational fishing became prohibited in these areas. In order to evaluate the effects of these no-take MPAs, the structure of their fish assemblages and of adjacent control areas without fishing restrictions were studied between 2011 (immediately after implementation) and 2013 (two years after implementation). A total of 4 sampling campaigns were conducted (summer 2011, winter 2012, summer 2013 and winter 2013) using trammel nets and bottom trawl. Ichthyofaunal assemblages from the no-take MPAs (treatment) were compared with adjacent areas (controls) and changes evaluated as a function of time since protection. Results revealed significant increase in fish abundance after the implementation of the no-take MPAs. Furthermore, significant differences in the structure of fish assemblages (abundance and fish size) between protected and neighbouring areas were rapidly observed upon the implementation of the no-take MPAs. In addition, specimens of larger size occurred more frequently within Ilha do Pessegueiro no-take MPA in the last year of the study. Overall, despite the young age of these no-take MPAs, changes on the structure of their fish assemblages were already evident after only two years of protection, indicating that management measures such as MPA designation may play an important role to promote fisheries sustainable exploitation as well as to protect species with conservation interest.

Changes in the fish community structure after the implementation of Marine Protected Areas in the south western coast of Portugal

Event Abstract Back to Event Changes in the fish community structure after the implementation of Marine Protected Areas in the south western coast of Portugal Tadeu J. Pereira1, 2*, Joana Manique1, Bernardo Quintella1, 3, Nuno Castro1, Pedro R. Almeida2 and José L. Costa1, 3 1 MARE-ULisboa, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, Portugal 2 MARE - UEvora, Departamento de Biologia, Escola de Ciências e Tecnologia, Universidade de Évora, Évora, Portugal., Portugal 3 Departamento de Biologia Animal, Faculdade de Ciências da Universidade de Lisboa, Portugal Marine Protected Areas (MPAs) are increasingly being recommended as management tools for biodiversity conservation and fisheries. With the purpose of protecting the region’s biodiversity and prevent the over exploitation of marine resources, in February 2011 the MPAs of Ilha do Pessegueiro and Cabo Sardão were implemented in the “Parque Natural do Sudoeste Alentejano e Costa Vicentina “(PNSACV) Natural Park, south western coast of Portugal. In these areas, commercial and recreational fishing became prohibited. In order to evaluate the effects of these MPAs, the structure of its fish communities and of adjacent control areas without fishing restrictions were studied in 2011/12 (immediately after implementation) and 2013 (two years after implementation). A total of 4 sampling campaigns were conducted (summer 2011, winter 2012, summer 2013 and winter 2013) using bottom trawl and gillnets. Faunal communities from the MPAs (treatment) were compared with adjacent areas (controls) and changes evaluated with time. Results revealed significant changes on abundance, having this parameter a slight increase after the implementation of the MPAs. Also, significant differences were observed on the structure of the protected areas communities when compared with neighbouring areas where fishing was still allowed, even though the small amount of time elapsed. In addition, specimens of larger size occurred more frequently within Ilha do Pessegueiro MPA in the last year of the study. Despite the young age of these MPAs, changes on their fish communities’ structure are already visible after only 3 years of protection, showing that these management measures may promote sustainable exploitation of fishing resources as well as protect species with conservation interest, thus leading to a global biodiversity increase. Acknowledgements This study is part of project PROTECT (31-03-05-FEP-0012; www.protect.uevora.pt) co-funded by Programme PROMAR. Keywords: marine reserve, MPA effectiveness, Fishing prohibition, no take zone, PNSACV Marine Park Conference: XV European Congress of Ichthyology, Porto, Portugal, 7 Sep - 11 Sep, 2015. Presentation Type: Oral Presentation Topic: Ecology, Conservation and Invasive Species Citation: Pereira TJ, Manique J, Quintella B, Castro N, Almeida PR and Costa JL (2015). Changes in the fish community structure after the implementation of Marine Protected Areas in the south western coast of Portugal. Front. Mar. Sci. Conference Abstract: XV European Congress of Ichthyology. doi: 10.3389/conf.fmars.2015.03.00025 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 23 Oct 2015; Published Online: 04 Nov 2015. * Correspondence: Dr. Tadeu J Pereira, MARE-ULisboa, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, Lisbon, Portugal, tjpereira@fc.ul.pt Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Tadeu J Pereira Joana Manique Bernardo Quintella Nuno Castro Pedro R Almeida José L Costa Google Tadeu J Pereira Joana Manique Bernardo Quintella Nuno Castro Pedro R Almeida José L Costa Google Scholar Tadeu J Pereira Joana Manique Bernardo Quintella Nuno Castro Pedro R Almeida José L Costa PubMed Tadeu J Pereira Joana Manique Bernardo Quintella Nuno Castro Pedro R Almeida José L Costa Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Evaluation of stakeholder perspectives on the management of the stalked barnacles (Pollicipes pollicipes) resource in the Parque Natural do Sudoeste Alentejano e Costa Vicentina, Portugal

The stalked barnacle, Pollicipes pollicipes, is a shellfish resource which has been traditionally harvested by the coastal communities of the Iberian Peninsula. However, in recent years Pollicipes has attracted increased harvesting pressure due to its high market value. In a national park on the south-western coast of Portugal, legislation was formulated to address the overharvesting of this resource; however, its success has been limited due to lack of consensus among stakeholders. A Systems Approach Framework (SAF) was used to assess the socio-economic and cultural issues surrounding the harvest of Pollicipes. As part of this, interviews and a questionnaire survey were undertaken in the municipality of Vila do Bispo, in order to explore the perspectives of the shell fishers, local residents and restaurateurs. The majority of the stakeholders believed that the resource was overharvested and that their needs should be considered as part of the legislation formulation process. The stakeholders also agreed that the local market should be re-established and that the temporal closure period should be reconsidered. Stakeholder opinions differed with regard to the level of coastal management enforcement required, the licence distribution process and the restrictions implemented by national park authorities. It is concluded that using information such as that gathered from local stakeholders, it should be possible to effectively extend the SAF to simulate scenarios for future management options.

Shell strength and fishing damage to the smooth clam (Callista chione): simulating impacts caused by bivalve dredging

Abstract Vasconcelos, P., Morgado-André, A., Morgado-André, C., and Gaspar, M. B. 2011. Shell strength and fishing damage to the smooth clam (Callista chione): simulating impacts caused by bivalve dredging. – ICES Journal of Marine Science, 68: 32–42. The smooth clam Callista chione is exploited by a fleet of dredgers along the southwestern coast of Portugal and suffers from a high incidence of shell damage. The force required to break C. chione shells in relation to fishing impacts and dredge damage is quantified. Fishing trials and shell-strength measurements (compression and compaction experiments) were performed to determine whether shell damage was attributable to the direct impact of the dredge teeth or to sediment compaction. A three-dimensional model of C. chione was subjected to simulated force by the finite element method. Analyses of damage areas and breakage patterns revealed two groups of samples, one containing the samples from compression experiments and another with the samples from dredging and compaction experiments, suggesting that most shell damage was attributable to compaction within the sediment. Information is provided to help improve the design of bivalve dredges, by increasing both length and angle of the dredge teeth, which would reduce the compaction force and distribute it differentially within the sediment, forcing upward movement of the bivalves.

Spatial distribution of subtidal meiobenthos along estuarine gradients in two southern European estuaries (Portugal)

The spatial variation in abundance and composition of subtidal meiobenthos communities was studied in two Portuguese estuaries under distinct degrees of anthropogenic pressure. Samples were collected from 20 sampling stations along both estuarine gradients from freshwater (<0.5) to euhaline areas (>30). Of these stations 11 were located in the Mondego estuary, a system exposed to high anthropogenic stress, and 9 in the Mira estuary, a naturally stressed system located inside the Natural Park ‘Costa Vicentina’ (south-western coast of Portugal).Total meiobenthos density was higher in the Mira estuary and in both estuaries the community was dominated by nematodes. Among the twelve taxa identified in the Mira estuary, Harpacticoid copepods and Polychaeta were the second and the third most abundant groups respectively. In the Mondego estuary, Polychaeta was the second while Harpacticoid copepods was the third most abundant group in the thirteen total taxa recorded.Estuarine gradients of salinity, particles size and water nutrients were clearly detected in both estuaries and there was significant spatial heterogeneity in abundance and composition of the subtidal meiobenthos communities along these environmental gradients. Accordingly, three distinct sections were identified in both estuaries: (i) freshwater sections, where total density, and density of nematodes and Harpacticoid copepods reached minimum values; (ii) oligohaline and mesohaline sections, where the total density was low and diversity was poor; and (iii) polyhaline and euhaline sections, where both total density and diversity reached the highest values.The similar spatial distribution of meiobenthos assemblages in both estuaries suggests that natural stressors may be the major factors controlling the physicochemical conditions that determine meiobenthos community patterns. The mesoscale variability of subtidal meiobenthos density and composition within estuaries (in the order of kilometres) seems to be more important than the variability between estuaries (at the scale of hundreds of kilometres), a common feature in intertidal systems. From the management point of view, these results, based on higher taxa resolution, represent an obvious constraint to the applicability of ecological quality evaluation tools.

Age determination and growth rate of a Callista chione population from the southwestern coast of Portugal

AB Aquatic Biology Contact the journal Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections AB 5:97-106 (2009) - DOI: https://doi.org/10.3354/ab00119 Age determination and growth rate of a Callista chione population from the southwestern coast of Portugal Paula Moura, Miguel B. Gaspar*, Carlos C. Monteiro Instituto Nacional de Recursos Biológicos (INRB, I.P.) / IPIMAR, Avenida 5 de Outubro s/n, 8700-305 Olhão, Portugal *Corresponding author. Email: mbgaspar@cripsul.ipimar.pt ABSTRACT: The age and growth of the smooth clam Callista chione from the southwestern coast of Portugal were estimated during a 1 yr study period by using both the surface growth rings and internal shell microgrowth lines (by acetate peel method). The von Bertalanffy growth curves obtained by these 2 methods were, respectively: Lt = 91.9[1 – e–0.18 (t+0.22)] and Lt = 98.1[1 – e–0.15 (t+0.43)]. Based on these, the counting of surface growth rings is appropriate for a quick age estimation of individuals up to 10 yr old (~75 mm shell length, SL). For older specimens, analysis of the growth lines in the cross section of shells is recommended, because close to the shell border it becomes difficult to distinguish growth rings on the shell surface. Rapid shell growth occurred in spring and summer, whereas slow growth occurred during autumn and winter, with the deposition of an annual growth ring. The overall growth performance and the phi-prime index were used to compare growth parameters with data from literature about venerid bivalves. These parameters indicated that Callista spp. have a higher growth performance than other venerid bivalves and this is correlated with geographical latitude. The smooth clam achieves sexual maturation at 4 yr of age and reaches the minimum landing size (60 mm SL) after 5 yr. KEY WORDS: Callista chione · Smooth clam · Age · Growth rate · Growth performance · Surface rings · Acetate peel · Portugal Full text in pdf format PreviousCite this article as: Moura P, Gaspar MB, Monteiro CC (2009) Age determination and growth rate of a Callista chione population from the southwestern coast of Portugal. Aquat Biol 5:97-106. https://doi.org/10.3354/ab00119 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in AB Vol. 5, No. 1. Online publication date: February 24, 2009 Print ISSN: 1864-7782; Online ISSN: 1864-7790 Copyright © 2009 Inter-Research.

Gametogenic cycle of the smooth clam Callista chione on the south-western coast of Portugal

The gametogenic cycle of the smooth clam Callista chione off the Arrábida region was studied throughout a 17-month period (from January 2004 to May 2005) using standard histological techniques, mean oocyte diameters and a condition index. This species showed a synchronism between sexes both in terms of gametogenic development and spawning. The results indicated that sex-ratio was not significantly different from parity. In January 2004, the gametogenic cycle had already begun and ended in late October 2004. Three spawning peaks were detected: January–March, April–May and August–October. No resting period was observed and a new gametogenic cycle began in early November, immediately after the spawning period. The analysis of the oocyte diameter enabled predicting the main spawning periods, which appear to be largely governed by seawater temperature. The condition index evolved according to the reproductive cycle of the species, with the highest values being observed prior to the main spawning periods. The size at first maturity estimated for C. chione was 50.81 mm.

Uncertainty in predictions of oil spill trajectories in a coastal zone

A method is introduced to determine the uncertainties in the predictions of oil spill trajectories using a classic oil spill model. The method considers the output of the oil spill model as a function of random variables, which are the input parameters, and calculates the standard deviation of the output results which provides a measure of the uncertainty of the model as a result of the uncertainties of the input parameters. In addition to a single trajectory that is calculated by the oil spill model using the mean values of the parameters, a band of trajectories can be defined when various simulations are done taking into account the uncertainties of the input parameters. This band of trajectories defines envelopes of the trajectories that are likely to be followed by the spill given the uncertainties of the input. The method was applied to an oil spill that occurred in 1989 near Sines in the southwestern coast of Portugal. This model represented well the distinction between a wind driven part that remained offshore, and a tide driven part that went ashore. For both parts, the method defined two trajectory envelopes, one calculated exclusively with the wind fields, and the other using wind and tidal currents. In both cases reasonable approximation to the observed results was obtained. The envelope of likely trajectories that is obtained with the uncertainty modelling proved to give a better interpretation of the trajectories that were simulated by the oil spill model.

Coastal evolution and Holocene ostracods in Melides lagoon (SW Portugal)

A multidisciplinary study covering sedimentology (texture, carbonate and organic matter content, clay mineralogy), geochemistry (major, minor and trace elements, isotopes), palaeoecolgy (ostracods) and isotopic dating ( 14C) has been carried out on two long cores (MB-40.0 m and MIGM-34.0 m) retrieved from the barrier and the alluvial plain margining the Melides lagoon (south-western coast of Portugal). The interpretation of the whole data set allowed the establishment of an evolutionary model for this lowland since the Late Glacial. This model includes four stages. It starts with a fluvial terrestrial environment, replaced by an estuarine to fully marine one (circa 9500 cal BP), due to the rapid rise in sea level recorded during the first phase of the Holocene transgression. The deceleration of sea level rise favoured the emplacement of a sandy barrier (circa 5900 cal BP) that promoted the differentiation of a coastal lagoon which has been progressively filled with fluvial sediments. The ostracod fauna in both locations includes 38 species of littoral to sublittoral/phytal marine forms (mainly Urocythereis britannica, Carinocythereis whitei, Loxoconcha rhomboidea, Pontocythere elongata, Semicytherura sella, Semicytherura acuta, Basslerites cf. berchoni, Hiltermannicythere emaciata) and brackish water forms ( Cyprideis torosa, Loxoconcha elliptica), which clearly characterize the signature of both the marine and lagoonal episodes, respectively.

REPRODUCTIVE PATTERNS OF POLLICIPES POLLICIPES (CIRRIPEDIA: SCALPELLOMORPHA) ON THE SOUTHWESTERN COAST OF PORTUGAL

The brooding period of Pollicipes pollicipes on the southwestern coast of Portugal in 1991 began in March and extended to October, and was more intense from April-September. Brooding activity in small animals (12.5-15 mm, rostrocarinal distance, RC) was significantly less than in large animals (RC > 15 mm). Brooding activity patterns of this species were considered to be similar at different tidal levels and subtidally. Crowded animals brooded less than uncrowded animals, but results could have been confounded by the fact that only one site was considered. Individuals apparently produce asynchronous broods. Estimates of the annual number of broods varied between 1 (crowded animals), 1 or 2 (small, uncrowded animals), and 4 (large, uncrowded animals). Small animals (mean RC = 15.4 mm; 16,229 eggs) produced about half the number of eggs of large animals (mean RC = 19.6 mm; 34,172 eggs). Fecundity was considered to be a function of size (RC) (after logarithmic transformation; r2 = 0.62). A variable number of eggs was produced by animals of the same size; animals with an RC from 23-25 mm ranging from 30,000-130,000 eggs per brood. Fecundity patterns were considered similar in relation to tidal level, crowding, and time in the reproductive season.

Direct evidence of meddy formation off the southwestern coast of Portugal

The formation of a Mediterranean Water eddy, or meddy, was observed directly for the first time off the southwestern coast of Portugal near Cape St. Vincent. The formation event is revealed in the 30-day trajectory of a RAFOS float deployed in the lower core of the Mediterranean Undercurrent in the Gulf of Cadiz. For the first several days after deployment, this float was advected westward in the Undercurrent at a speed of about 0.4 m s −1, generally paralleling the topography. Just after passing Cape St. Vincent, where the coast turns abruptly northward, the float began looping anticyclonically, indicating that it had become trapped in the core of a new meddy. The meddy translated first westward, then southwestward along the southern flank of Gorringe Bank. The float rotated around the meddy center with azimuthal speeds of 0.20–0.25 m s −1 at a radius of about 10 km. The rotation period was on the order of three days, and the average translation speed of the meddy over 25 days was 0.08 m s -1. Observations of this and four additional 30-day trajectories indicate (1) persistent westward flow of the Undercurrent along the south coast of Portugal, (2) a tendency for the lower core of the Undercurrent to separate from the continental boundary after passing Cape St. Vincent, and (3) evidence of anticyclonic looping west of Cape St. Vincent. These preliminary results confirm the speculation that the region off Cape St. Vincent is one site of meddy generation.