The catchment has never been cultivated and it originally supported
a rangeland vegetation cover. In 1968 it was planted with
Eucalyptus occidentalis trees and these trees have been harvested
twice (in 1978 and 1990), with the tree cover being subsequently
restored by natural regrowth. Logging operations took place across
the entire area of the catchment and involved the removal of ca.
25e40 m3 of biomass during each cutting campaign. The harvested
timber was extracted from the catchment manually, in order to
minimise the impact of the harvesting operations on the soil surface.
The tree cover is not uniform within the catchment, and about
20% of its area, primarily along its northern margin, is characterised
by discontinuous trees and a sparse grass cover. Elsewhere, the tree
cover is relatively uniform. The soils under the eucalyptus trees are
largely devoid of ground cover and much of the surface beneath the
trees and sparse grass cover is therefore bare. The bare soils are
exposed to rainsplash and surface runoff during heavy rainfall and
significant sheet erosion occurs at such times. The area with
discontinuous tree cover is the area of greatest soil loss (Porto et al.,
2005).