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- Macroalgas das Berlengas e Costa de Prata: Do conhecimento à utilizaçãoPublication . Franco, João N.; Lemos, Marco F.L.; Neto, João M.A Costa de Prata, região litoral compreendida entre Esmoriz (Aveiro) e Torres Vedras (Lisboa), caracteriza-se, a norte, pelo domínio de praias de areia fina cortadas pelos maciços rochosos da Serra da Boa Viagem, da Nazaré e de São Martinho do Porto. Já a sul de Peniche, dominam os afloramentos rochosos, submareais e intermareais, que frequentemente emergem do mar em imponentes arribas que vincam o limite continental. É nesta zona que podemos encontrar o arquipélago das Berlengas, um território insular que se encontra ao abrigo de um regime especial de proteção, a Reserva Marinha das Berlengas, bem conhecido pela sua riqueza natural.
- Brain as a target organ of climate events: Environmental induced biochemical changes in three marine fish speciesPublication . Vieira, R.; Marques, S.M.; Neto, J.M.; Barría, P.; Marques, J.C.; Gonçalves, F.J.M.; Gonçalves, A.M.M.The present study aims to examine physiological and biochemical response of three commercial fish species (Dicentrarchus labrax; Platichthys flesus and Solea solea), over contrasting environmental dynamics: an extremely dry (2012) and flood (2014) years, in a shallow temperate southern European estuary, the Mondego Estuary (Portugal). Physiological and biochemical biomarkers were evaluated by a principal component analysis (PCA), which allowed to conclude that severe climatic events affected the set of fish species analyzed, revealing two distinct annual brain antioxidant responses. The drought episode affected the physiological state of the organisms, as well as increased brain antioxidant potential, strongly associated with fluctuations in environmental drivers (salinity and dissolved oxygen), however, ROS have not been effectively neutralized by antioxidant defence system causing lipid peroxidation. During flood episode was stated a general depletion of the antioxidant potential in the analyzed fish species, affected by interactions with chemical compounds, increased by a combination of high precipitation and associated runoff, probably, increasing nutrient and contaminant load at the Mondego estuary. Nevertheless, lipid peroxidation remained low, related to the action of non-enzymatic antioxidants, since that the studied fish species had optimal physiological status and high nutritive reserves. According to the present work we consider that brain enzymatic depletion may be organ-specific, looking to the greater vulnerability of brain's proteins to degradation compared to lipids. The role of enzymatic mobilization on fish brains is not extensively yet known, but our results suggest that brain seems to be metabolic sensitive to salinity and dissolved oxygen fluctuations. This is the first approach made to evaluate the physiological and biochemical responses of the brain of aquatic organisms’ to extreme climatic events and to establish reference values to determine the effects of extreme climate events to aquatic species.
- Effectiveness of two western Iberian Peninsula marine protected areas in reducing the risk of macroalgae invasionPublication . Blanco, A.; Neto, J.M.; Trancoso, J.; Lemos, M.F.L.; Olabarria, C.Marine ecosystems are facing major anthropogenic disturbances, including loss of biodiversity, eutrophication, and biological invasions. Thus, attention has raised on marine conservation actions to preserve habitat resilience and biodiversity. Marine Protected Areas (MPAs) play an essential role in marine conservation as they are usually designated to provide marine ecosystem resilience of native communities to human-induced impacts (including non-native introductions) while contributing with positive effects on other ecosystem services. The introduction of a new species in novel marine habitats has been attributed to biotic, abiotic, and anthropogenic factors. In the present study, the effects of native functional diversity, wave exposure were studied, and for the first time, marine protection was addressed concerning the invasion success of six macroalgae in two MPAs in the NW Iberian Peninsula. The correlation between the presence/absence of some native functional groups and the invasion success of some invasive species highlighted the importance of conserving native canopy-formers. Despite local differences, wave exposure did not affect invasion success. The protection provided by both MPAs was very limited to prevent the establishment and spread of the most abundant invasive macroalgae. Therefore, stricter management plans should be implemented to ensure native ecosystem resilience within the MPAs.
- The effects of the invasive seaweed asparagopsis armata on native rock pool communities: evidences from experimental exclusionPublication . Silva, Carla; Lemos, Marco F.L.; Gaspar, Rui; Gonçalves, Carlos; Neto, João M.Biological invasions represent a threat to ecosystems, through competition and habitat destruction, which may result in significant changes of the invaded community. Asparagopsis armata Harvey 1855 is a red macroalgae (Rodophyta) globally recognized as an invasive species. It is found from the intertidal to shallow subtidal areas, on rock or epiphytic, forming natural vegetation belts on exposed coasts. This study evaluated the variations on native intertidal seaweed and macroinvertebrate assemblages inhabiting rock pools with and without the presence of the invasive macroalgae A. armata. To achieve this, manipulation experiments on Atlantic (Portugal) rock pools were done. Three rock pools were maintained without A. armata by manual removal of macroalgae, and three others were not experimentally manipulated during the study period and A. armata was freely present. In this study the variations between different rock pools were assessed. Results showed different patterns in the macroalgae composition of assemblages but not for the macrobenthic communities. Ellisolandia elongata (J. Ellis & Solander) K.R. Hind & G.W. Saunders 2013 was the main algal species affected by the invasion of A. armata. Invaded pools tended to show less macroalgal species richness, showing a more constant and conservative structure, with lower variation of its taxonomic composition than the pools not containing A. armata, where the variability between samples was always higher. Despite the importance of the achieved results, further data based on observation of long-term series are needed, in order to further understand more severe effects of the invader A. armata on native macroalgal assemblage.
- Mapping invasive macroalgae in the Western Iberian Peninsula: a methodological guidePublication . Blanco, A.; Lemos, Marco F.L.; Pereira, Leonel; Gaspar, Rui; Mouga, Teresa; Neto, João M.; Troncoso, J. S.; Olabarria, Celia
- Spotting intruders: Species distribution models for managing invasive intertidal macroalgaePublication . Blanco, A.; Larrinaga, A.R.; Neto, J.M.; Troncoso, J.; Méndez, G.; Domínguez-Lapido, P.; Ovejero, A.; Pereira, L.; Mouga, T.; Gaspar, R.; Martínez, B.; Lemos, M.F.L.; Olabarria, C.Invasive macroalgae represent one of the major threats to marine biodiversity, ecosystem functioning and structure, as well as being important drivers of ecosystem services depletion. Many such species have become well established along the west coast of the Iberian Peninsula. However, the lack of information about the distribution of the invaders and the factors determining their occurrence make bioinvasions a difficult issue to manage. Such information is key to enabling the design and implementation of effective management plans. The present study aimed to map the current probability of presence of six invasive macroalgae: Grateloupia turuturu, Asparagopsis armata, Colpomenia peregrina, Sargassum muticum, Undaria pinnatifida, and Codium fragile ssp. fragile. For this purpose, an extensive field survey was carried out along the coast of the north-western Iberian Peninsula. Species distribution models (SDMs) were then used to map the presence probability of these invasive species throughout the study region on the basis of environmental and anthropogenic predictor variables. The southern Galician rias were identified as the main hotspots of macroalgal invasion, with a high probability of occurrence for most of the species considered. Conversely, the probability of presence on the Portuguese coast was generally low. Physico-chemical variables were the most important factors for predicting the distribution of invasive macroalgae contributing between 57.27 and 85.24% to the ensemble models. However, anthropogenic factors (including size of vessels, number of shipping lines, distance from ports, population density, etc.) considerably improved the estimates of the probability of occurrence for most of the target species. This study is one of the few to include anthropogenic factors in SDMs for invasive macroalgae. The findings suggest that management actions aimed at controlling these species should strengthen control and surveillance at ports, particularly in southern Galician rias. Early detection should be of main concern for risk assessment plans on the Portuguese coast.