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The response of fluvial systems to land use and climate change varies depending on catchment size. While forcing-response mechanisms of small catchments are reasonably well understood, the response of larger drainage basins is less clear. In particular, the impact of land use and climate change on the Rhine system is poorly understood because of the catchment size (185 000 km2) and the long history of human cultivation, which started approximately 7500 years ago. A sediment budget is calculated to specify the amount of alluvial sediment that was deposited during the Holocene and to estimate long-term soil erosion rates. The results suggest that 59±14 X 109 t of Holocene alluvial sediment is stored in the non-alpine part of the Rhine catchment (South and Central Germany, Eastern France, The Netherlands). About 50% of Holocene alluvial sediment is deposited along the trunk valley and the delta (Upper Rhine, Lower Rhine, coastal plain), while the rest is stored along the tributary valleys. The floodplain sediment storage corresponds to a mean erosion rate of 0.55±0.16 t/ha per yr (38.5±10.7 mm/kyr) across the Rhine catchment outside the Alps. This Holocene-averaged estimate amounts for sediments that were delivered to the channel network and is at the lower limit of erosion rates from other studies of different methodology.

Within the project “The Temporal occurrence and forecasting of landslides in the European Community” a review of the use of databases and GIS for landslide research has been accomplished. It shows a high potential of these techniques in storing spatial and temporal landslide data (landslide inventories) and in applying different modelling approaches to landslide hazard assessments at various scales. There are three major strategies in European landslide research using GIS and database technologies. At medium and broad scales different combinations of landslide data with factor maps (e.g. slope angle, lithology and geomorphological units) lead to static susceptibility and hazard assessments, which allow probability evaluations for future landslide occurrences. At local scales process models to simulate trajectories of paths for slope processes and deterministic slope stability models are in use. In landslide frequency analysis, temporal database information are correlated with recent and historical triggering factors (e.g. precipitation and precipitation indices) to calculate temporal probabilities for landslide forecasting. However, despite encouraging progress in applying computer technologies in European landslide research, the potential of these tools is still largely untested. Furthermore, it is clear that sophisticated technology cannot replace field work, interdisciplinary research strategies, and critical testing of the reliability of the model results.