Identification of Study Sites for Placement of Sediment Traps in Vegetated Buffer Strips

The aim of this contribution was to outline the decision procedure for selecting potential sites suitable for installing sediment traps in vegetation buffer strips in the Fugnitz catchment, Austria. The selection procedure consisted of GIS data processing where the contributing areas of specific sites were specified according to the selected criteria (i.e. slope above 2°, vegetation strip in between agriculturally used land and river network, contributing area of at least 300 m²). Available landuse maps were updated with formerly not-digitized structures potentially influencing connectivity (e.g. ephemeral streams and road ditches) which were mapped in the field. From 31 pre-defined sites 15 were selected, taking into account as additional selection criteria the slope angle, soil erodibility and size of the contributing area. Two sites were selected for further investigations – i.e. installation of the sediment traps in vegetation filter strips collecting event-based sediment yields from adjacent arable fields. We conclude that GIS analysis has shown to be useful for the first step-delineation of potential sites of interest on the catchment scale. However, field-based surveys have been shown to be inevitable to obtain on-site information on vegetation characteristics and fine-scale topographic and management information.