Stefan Wirtz Vom Fachbereich VI (Geographie/Geowissenschaften ...

Experimentelle Rinnenerosionsforschung vs. Modellkonzepte – Quantifizierung der hydraulischen und erosiven Wirksamkeit von Rinnen
1. Which proportion of the test site area is drained by rill networks?
2. Which runoff intensities appear in the rills, which on the interrill-areas?
3. How effective is the rill erosion compared to the interrill erosion in the catchment?
2 Material and Methods
2.1 Study Area
The study area Freila is situated in the Hoya de Baza sedimentary basin (see figure 1) in
Andalusia (Southeast Spain). The bedrock mostly consists of Pliocene sedimentary rocks, i.e.
marls and fine grained sandstones. At the surface the marls and sandstones are weathered to
calcareous loamy to sandy lithosols. The semi-arid climate is characterised by a mean annual
temperature of about 14.2 °C. The annual precipitation is down to only 368 mm, with a high
inter-annual variability. The vegetation is dominated by low shrub-land of Thymus vulgaris
and Stipa tenacissima grassland. The land use on the southern lake-side of the Negratin
reservoir is dominated by abandoned cereal fields, which are extensively grazed by flocks of
sheep. Agricultural land use comprises mainly cereal dry-farming [23]. At the top of the
catchment, a gully has developed.
Figure 1: Test site in Andalusia (UTM: 509864 E – 4154369 N)
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