Global sediment flux by rivers

Applicant: Prof. Dr. Matthias Hinderer, Prof. Dr. Peter M. Süss

Funding: DFG 643/1-1 normal procedure

Persons in charge: Holger Schäuble

Duration: 2002 – 2004

Summary

Major objective of this project was to apply new methods in order to improve the prediction of global sediment yield. We compiled a data base of 1523 different river basins with a size of 90 000 km2 on average. Based on a global and regional (USA) GIS the data were analysed with respect to controlling factors. The following new strategies have been pursuit:

• a new simulation module which considers the spatial and temporal links of sediment transport on a local scale
• a module by which the impact of reservoirs and other sinks can be considered and measured data be corrected to pre-impact conditions

The new strategies have been implemented through a newly developed programme “Sediment Yield Tools” which was applied to a data base of the USA. We received a multi-variate regression model with a coefficient of determination of 0.56 and a model efficiency of 0.55 (according to Nash & Sutcliffe, 1970) which improves older model with a value below 0.3. A similar improvement can be achieved for global data. Our calculated total sediment export from the continents to the oceans was 21*109 t/a, which corresponds to the average of existing estimations. Because of a much better data base we got more accurate estimates for the USA were we also studied the impact of reservoir constructions during the 20ies century and ran scenarios for climate change.