Seminario: Sediment transport under waves based on velocity and acceleration skewnesses
Inicio: 23/05/2018 12:00 - Final: 23/05/2018 13:00Lugar: Sala de Seminarios, IMEDEA
Sediment transport under waves based on velocity and acceleration skewnesses
Speaker: Daniel Conti (Doctoral Candidate, IMEDEA)
Properly modeling the sediment transport under water waves is critical to understand morphodynamic behaviors such as sandbar migrations. In the last two decades, the influence of the wave assymetries (velocity and acceleration skewnesses mainly) has been pointed to be a key issue to explain, e.g., onshore sandbar migrations under mild wave conditions when wave-induced currents are small. There is still, however, a lack of knowledge, and the expressions that relate the sediment transport to velocity and/or acceleration skewnesses are site-specific. Departing from a intra-wave process-based sediment transport mode (which is checked against experimental data), from a well-known family of wave shapes and from a proper dimensional framework, in this work we propose a general expression for bedload sediment transport under waves. The expression found is not site-specific and, compared to the process-based model results, the coefficient of determination is R² = 0.993. Further, the obtained equation has some similarities with expressions in the literature that are discussed.
Inicio: 24/05/2018 12:00 - Final: 24/05/2018 14:00Lugar: Sala de Seminarios, IMEDEA
Fairy circles in Posidonia meadows
Speaker: Damià Gomila
Researcher at the IFISC (CSIC-UIB)
Abstract: Posidonia Oceanica is a marine clonal plant of capital importance in the Mediterranean sea. It forms extensive meadows which provide important ecosystem services. Close to the cost such meadows are not uniform but display a variety of spatial patterns. In this seminar I will show a simply model for clonal growth able to reproduce the diversity of seascapes observed in these ecosystems as emerging from plant interactions within the meadow. These seascapes include two extreme cases, a continuous meadow and a bare landscape, along with intermediate states that range from the occurrence of persistent but isolated fairy circles, or dissipative solitons, to seascapes with multiple gaps, banded vegetation, and leopard skin patterns consisting of bare soil dotted with plant patches. The different seascapes observed hold diagnostic power as to proximity of seagrass meadows to extinction points.
18/05/2018 Seminar: Sediment transport under waves based on velocity and acceleration skewnesses
15/05/2018 El IMEDEA participa en el FESTIVAL POSIDONIA MALLORCA 2018
Bienvenidos al Instituto Mediterráneo de Estudios Avanzados (IMEDEA),
centro mixto de investigación entre el Consejo Superior de Investigaciones
Científicas (CSIC) y
la Universidad de las Islas Baleares (UIB).