Erosão na margem do estuário dos Bons Sinais - região das Gazelas no distrito de Quelimane

Abstract

Erosion has been one of the problems that affect the coastal zones over the world as well as in Mozambique. The Gazela’s area has been affected by erosion 10 years ago. This problem is affecting local communities, losing habitations, forming and leisure spaces. Field works with the objectives of identifying the causes of erosion in this area took place in between may to December 2018. Many parameters were evaluated such as current intensity, tidal height, wave height, wind intensity, precipitation and sediments analyses. The results points that current velocity reach 123cm/s conducted by semi-diurnal tides with inequality of 3.5m in high tide and 1m in low tide which sometimes generate waves of 0.4m of height. The topography in 70m of extension point that the region presents a slope of 2.45º in which waves, sediments fragility due to pluviometric discharge. The current velocity is been the main agent that causes erosion. It is recommended the competitive authorities to make decision as to reduce erosion, because since 2002 to December 2018, erosion affected 68m regarding a middle velocity of 4.1m/year.