Percorrer por autor "Brito, Ana C."
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- Anthropogenic, direct pressures on coastal wetlandsPublication . Newton, Alice; Icely, John; Cristina, Sónia; Perillo, Gerardo M. E.; Turner, R. Eugene; Ashan, Dewan; Cragg, Simon; Luo, Yongming; Tu, Chen; Li, Yuan; Zhang, Haibo; Ramesh, Ramachandran; Forbes, Donald L.; Solidoro, Cosimo; Béjaoui, Béchir; Gao, Shu; Pastres, Roberto; Kelsey, Heath; Taillie, Dylan; Nhan, Nguyen; Brito, Ana C.; de Lima, Ricardo; Kuenzer, ClaudiaCoastal wetlands, such as saltmarshes and mangroves that fringe transitional waters, deliver important ecosystem services that support human development. Coastal wetlands are complex social-ecological systems that occur at all latitudes, from polar regions to the tropics. This overview covers wetlands in five continents. The wetlands are of varying size, catchment size, human population and stages of economic development. Economic sectors and activities in and around the coastal wetlands and their catchments exert multiple, direct pressures.
- Assessing, quantifying and valuing the ecosystem services of coastal lagoonsPublication . Newton, Alice; Brito, Ana C.; Icely, John; Derolez, Valerie; Clara, Ines; Angus, Stewart; Schernewski, Gerald; Inacio, Miguel; Lillebo, Ana I.; Sousa, Ana I.; Bejaoui, Bechir; Solidoro, Cosimo; Tosic, Marko; Canedo-Arguelles, Miguel; Yamamuro, Masumi; Reizopoulou, Sofia; Tseng, Hsiao-Chun; Canu, Donata; Roselli, Leonilde; Maanan, Mohamed; Cristina, Sónia; Carolina Ruiz-Fernandez, Ana; de Lima, Ricardo F.; Kjerfve, Bjorn; Rubio-Cisneros, Nadia; Perez-Ruzafa, Angel; Marcos, Concepcion; Pastres, Roberto; Pranovi, Fabio; Snoussi, Maria; Turpie, Jane; Tuchkovenko, Yurii; Dyack, Brenda; Brookes, Justin; Povilanskas, Ramunas; Khokhlov, ValeriyThe natural conservation of coastal lagoons is important not only for their ecological importance, but also because of the valuable ecosystem services they provide for human welfare and wellbeing. Coastal lagoons are shallow semi-enclosed systems that support important habitats such as wetlands, mangroves, salt-marshes and seagrass meadows, as well as a rich biodiversity. Coastal lagoons are also complex social-ecological systems with ecosystem services that provide livelihoods, wellbeing and welfare to humans. This study assessed, quantified and valued the ecosystem services of 32 coastal lagoons. The main findings of the study are: (i) the definitions of ecosystem services are still not generally accepted; (ii) the quantification of ecosystem services is made in many different ways, using different units; (iii) the evaluation in monetary terms of some ecosystem service is problematic, often relying on non-monetary evaluation methods; (iv) when ecosystem services are valued in monetary terms, this may represent very different human benefits; and, (v) different aspects of climate change, including increasing temperature, sea-level rise and changes in rainfall patterns threaten the valuable ecosystem services of coastal lagoons.
- Integrating in situ and ocean color data to evaluate ecological quality under the water framework directivePublication . Brito, Ana C.; Garrido-Amador, Paloma; Gameiro, Carla; Nogueira, Marta; Calixto De Jesus Moita Garnel, Maria Teresa; Cabrita, Maria TeresaTheWater Framework Directive (WFD) aims at evaluating the ecological status of European coastal water bodies (CWBs). This is a rather complex task and first requires the use of long-term databases to assess the e ect of anthropogenic pressure on biological communities. An in situ dataset was assembled using concomitant biological, i.e., chlorophyll a (Chl a) and environmental data, covering the years from 1995 to 2014, to enable a comprehensive assessment of eutrophication in the Western Iberia Coast (WIC). Given the temporal gaps in the dataset, especially in terms of Chl a, satellite observations were used to complement it. Positive relationships between Chl a 90th percentile and nitrogen concentrations were obtained. The Land-Uses Simplified Index (LUSI), as a pressure indicator, showed no relationship with Chl a, except in Galicia, but it highlighted a higher continental pressure in the Portuguese CWBs in comparison with Galician waters. In general terms, the trophic index (TRIX) showed that none of the CWBs were in degraded conditions. Nevertheless, the relatively high TRIX and LUSI values obtained for the water body in front of Tagus estuary suggest that this area should be subject to continued monitoring. Results highlighted the usefulness of satellite data in water quality assessments and set the background levels for the implementation of operational monitoring based on satellite Chl a. In the future, low uncertainty and harmonized satellite products across countries should be provided. Moreover, the assessment of satellite-based eutrophication indicators should also include metrics on phytoplankton phenology and community structure.
- Spatial and temporal variations of Cockle (Cerastoderma spp.) populations in two portuguese estuarine systems with low directed fishing pressurePublication . Santos, Cátia; Cabral, Sara; Carvalho, Frederico; Sousa, António; Goulding, Thomas; Ramajal, João; Medeiros, João Paulo; Silva, Gilda; Angélico, Maria Manuel; Gaspar, Miguel; Brito, Ana C.; Costa, José Lino; Chainho, PaulaCockles are amongst the most exploited bivalve species in Portugal, playing an important ecological and socioeconomic role in coastal ecosystems. Two sympatric species of cockles, Cerastoderma edule (Linnaeus, 1758) and Cerastoderma glaucum (Bruguiere, 1789-1792) may co-occur in estuaries and coastal lagoons in mixed populations along the European Atlantic coast, namely in Portugal, France and the United Kingdom. The increasing importance of shellfish harvesting in Portugal requires a good knowledge of cockle stocks and temporal variability in stock levels to better inform sustainable management practices. Therefore, this study aimed at assessing spatial and temporal variations in cockle populations in two Portuguese estuarine systems where the species are exploited at low levels. Sampling was carried out using a clam dredge, covering the entire potential area of occurrence of cockles in the Tagus and Sado estuaries at around the same time of the year in each of the three sampling years (2015, 2018, and 2019). The abundance, spatial distribution and population structure of cockles were examined at each system. Moreover, several water and sediment parameters were measured to understand the influence of environmental conditions on the spatial distribution and abundance of cockles. The results obtained showed that cockles occur mostly in the intermediate areas of both estuarine systems and are more abundant in the Tagus estuary. Depth, average sediment grain size and the species Ruditapes philippinarum were the factors that better explained the probability of species occurrence. The population structure analysis indicated that natural mortality is constraining the cockle communities given the low abundance of adult individuals with marketable size in both estuaries. This study highlights the need for appropriate management measures to ensure the sustainability of these bivalve population stocks that have significant socioeconomic importance for local populations.
- The influence of coastal processes on inner shelf sediment distribution: The Eastern Algarve Shelf (Southern Portugal)Publication . Rosa, F.; Rufino, M. M.; Ferreira, O.; Matias, Ana; Brito, Ana C.; Gaspar, MiguelThis study examines sediment distribution patterns in the Southeastern Algarve inner shelf (southern Portugal), an area characterized by marked variations in its coastal environment and low continental supply of sediments. The specific goals of this study were to identify the principal sediment sources and the factors influencing sediment transport paths and deposition. A total of 199 samples, collected along the shelf from the Guadiana River mouth to Olhos de Agua, were analyzed. Grain-size distribution and parameters were measured for all the samples. Terrigenous and biogenic components of sand were identified in 38 samples, and results analyzed using multivariate non-linear multidimension scaling (MDS) and cluster analysis. Patterns of sediment distribution in this area of the inner shelf vary according to water depth and exhibit significant longshore variation, related mainly to coastal processes (littoral drift and storm currents) and to a lower degree to sediment sources. Sand is dominant at all depths, reflecting the influence of littoral drift in the supply and redistribution of shelf sediments. Fine and gravel-sized deposits are significant in specific areas and are usually associated with changes in sediment composition. Five sectors have been identified according to sedimentary dynamics. The results, based on geostatistical and multivariate analysis, have allowed detailed sediment distribution maps to be generated, which represent an update of the existing cartography and serve as a tool for the management of coastal and marine resources. They have been furthermore compared with inner shelf sediment dynamics in other regions worldwide, to distinguish between specific regional responses to forcing mechanisms and processes that are more generalized within this type of shelf environments. In this context, the results obtained results in the Algarve study area are of great interest for the understanding of sediment dynamics of sand dominated inner shelves with reduced continental supply.