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- Coastline evolution of the Portuguese south eastern coast: a high-resolution approach in a 65 years’ time-windowPublication . Nave, Silvia; Rebêlo, LuísAbstract. The coast, as the interface between land and sea, is a highly dynamic area, endangered by erosion and flooding, particularly at times of sea-level rise. At the present context of climate change, the use of scientific knowledge to understand coastal dynamics and coastal evolution assessment through time is essential to find a suitable management response for a successful adaptive coastal governance. It is proposed that the obtained high-resolution and long-term coastline change dataset is of crucial impor tance to improve the knowledge on mesoscale evolution of the Portuguese south-eastern coast, from Ancão to Vila Real de Santo António (VRSA), a 55 km long coastal stretch. The evolutionary trend, from 1950 to 2015, points to a general seaward progradation at the western (Barreta island) and eastern (Cacela peninsula – VRSA) sectors, and mostly an erosional trend at the central barrier island system (Culatra, Tavira and Cabanas islands). Moreover, a considerable average landward displacement of approximately 130 m is observed at Cabanas island. Regarding overall coastline movement, seaward displacement prevails, with a prograding coastline occupying approximately 54% of the studied sector even though this is mostly associated with human intervention on the coast. The exception is the Manta Rota - Monte Gordo sector where accumulation is likely related to natural processes. Considering the significant influence man-made interventions have had on the coastline evolution, it is believed that the natural evolutionary pattern would point to an overall erosional trend in the islands sector and a progradational trend from Manta Rota to VRSA beach.
- Patterns of sediment distribution on the Portuguese southeastern coastPublication . Nave, Silvia; Rebêlo, LuísSUMÁRIO: A granulometria dos sedimentos pode fornecer informações importantes sobre a origem e evolução dos ambientes sedimentares da zona costeira. Este trabalho apresenta a distribuição espacial da granulometria dos sedimentos no sotavento algarvio, resultante da análise de 395 amostras recolhidas em 133 perfis posicionados ao longo de uma faixa de 55km, desde a península do Ancão até Vila Real de Santo António. A análise preliminar dos resultados, apresentados em função do valor da média e agrupados nas classes normalizadas da escala de tamanho de grão (classificação de Wentworth), revela a ausência das classes granulométricas de areia muito fina e fina, mesmo na zona dunar, onde a classe de areia média domina no sector leste, e a de areia grosseira, no sector ocidental. O padrão geral de distribuição espacial da granulometria dos sedimentos exibe uma variação distinta ao longo da área de estudo, decorrente da exposição aos principais agentes forçadores (ondas e correntes).