| dc.description.abstract | Modern soil erosion triggered by anthropogenic forcing is a well studied
phenomenon, but few studies focus on erosion on a longer timescale, forced by
climatic changes. A better understanding of the way these long term climatic
forcings act on soil erosion is needed to prepare ourselves for the future. Colluvial
deposits form valuable archives of the past erosion on a hillslope. The West
Usambara Mountains in Tanzania form an ideal location for research on the past
erosion, since they are subjected to severe erosion, of which the present day part
is well studied and documented. In this study, colluvial stratigraphies are
interpreted and dated by OSL in order to reconstruct the geomorphic response of
the landscape to past environmental changes, caused by both natural and
anthropogenic forcings. The colluvial records, showing unstable periods with
erosion alternated with stable periods of pedogenesis, can be linked successfully
to the past climatic and anthropogenic history of the area. A reconstruction of the
erosion history from the last three centuries is created, based on the information
found in the colluvial deposits. This research proves that colluvium stratigraphies
have a high potential for holding valuable sedimentary archives of the past
erosion and environmental history. When interpreted and dated correctly,
colluvial deposits can be used successfully to reconstruct the erosional history of
an area. | |
