The Impact of Soil Erosion in the Upper Blue Nile on Downstream Reservoir Sedimentation

Population growth in the Blue Nile Basin has led to fast land-use changes from forest to agricultural land, which resulted in speeding up the soil erosion processes producing highly negative impacts on the local soil fertility and agricultural productivity. The eroded sediment is transported downstream by water and sinks in the lower basin where...

Overtopping on Grass Covered Dikes: Resistance and Failure of the Inner Slopes

A large part of the Vietnamese population is living close to the coast. The sea is an essential source for supporting lives. Coastal flooding, on the other hand, threatens the people, land and infrastructures every year. Some hundreds years ago, the first sea dikes were built in Thai Binh and Nam Dinh provinces. In the north, the coastline is...

Sand-mud erosion from a soil mechanical perspective

‘Wetlands’ in tidal lagoons and estuaries are among the most valuable ecosystems in the world. Managing these systems requires both a thorough knowledge and validated tools to predict their behavior and development. An important morpho-dynamic process herein is the erosion (‘pick-up’) of the bed, which are in inter-tidal areas often composed of...

Estuarine Ecosystem Engineering: Biogeomorphology in the estuarine intertidal

The aim of this thesis was to investigate how (macro)benthic organisms interact with the ecological functioning, erodibility and small- to medium-scale morphodynamics of estuarine intertidal sediment by modulating its composition and/or properties. In these interactions, scale is of great importance for the ecosystem engineers. The changes they...

Erosion and transport of bed-load sediment

In this thesis first a general derivation is given of the 'macro'-equations of mass- and linear-momentum balance that govern the mo'mentum transfer from a Newtonian fluid to rigid particles in a fluid-solid mixture. In particular, attention is paid to a) the attenuation of viscous-momentum transfer from the boundary to the interior of a granular...