Estudo da dinâmica da pluma de sedimentos oriundos de actividades de dragagens- estuário da Beira

Abstract

The Beira Estuary is very important as a marine system in Mozambique, contributing to biodiversity and with better fishing centers, it is still important for the port management of the city of Beira, being this the second largest port in Mozambique, the high movement of large ships. draft implies maintenance of the port's access channel, as it has suffered major siltation. At dredging undoubtedly has influences on the marine environment and can temporarily affect the abundance and distribution of marine species, change in circulation and bathymetry. This study focuses on the dispersion of the sediment plume from dredging activities in the estuary. from Beira, was carried out based on computational modeling and simulation (Delft3D model). The simulation results showed that tidal currents influence more on the transport of the sediment plume from surface dredging and bottom transport activities other forcing, river flood discharges contribute to the transport of sediments in suspension, wind speeds above 6 m/s are relevant for plume dispersion (inducing surface currents that carry sediment), the tidal currents follow the configuration of the access channel to the port of Beira, the concentration of sediments close to the surface was lower relatively close to the bottom, the sediment plume re-deposits in the access channel.