Estudo da influência da corrente de maré no transporte de sedimentos em suspensão no canal de Chuabo Dembe em Quelimane-Zambézia

Abstract

The present work shows a quantitative evaluation of the concentration of suspended solids from current velocity measurements related to sea level, the results show that the methodology is technically feasible and economically attractive. The main objective of this study was to study the influence of the tidal current on the transportation of suspended sediments during flood and ebb ot spring and neap. Two expeditions were carried out in the spring tide and two in the neap tide to make a comparative analysis of the situation of the quantity of sediment in suspension being transported and to try to understand which of the two tides has more influence in sediment transport, the expeditions were performed on days (16, 23, 30 July 2017 and 6 August of the same year). The sediment water mixture samples were collected through plastic bottles with a volume of 0.5L during flood and the ebb in an interval of one hour and the current velocity data were measured with the help of a float that was released in an interval of one hour and with the help of the bridge on that channel the width of the bridge was used as the space that the float had to travel, and with the help of a timer was measured the time in which the float took to cross the two sides of the bridge, the level of evil data was measured with the help of a tesserae that was programmed to take measurements at intervals of ten minutes. In the observations of the velocity of the current, it was verified that higher velocities are during the ebb, with the spring tide experiencing higher velocities in relation to the neap ones with 0.8 m/s during the ebb. The total balance between the two types of tide showed that the sediments flow more towards the inward channel with an estimated value of about +553.965 g/s.