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It should be stressed that these results give a broad overview of
the general pattern of the relative differences, rather than providing
accurateabsoluteerosion rates. It isalsonoteworthy thatdifferences
between sediment yield and soil loss can be very high. Research
findings suggest that soil loss within a catchment can be up to five
times greater than sediment yield due to the reduction of the total
eroded volumebydepositionwithin the catchment.
Consequently, a soil erosion figure of 12,6 tons/ha/year could
correspond with a sediment yield of 2,5 tons/ha/year. Compared
to Australia (4,1 tons/ha/year), the average predicted soil loss rate
for South Africa is three times as much. South Africa has a higher
soil loss rate than Australia, presumably due to extensive tillage-
based cultivation and overgrazing. More than 60% of the country is
currently under commercial and subsistence farming, while around
10% is under cultivation.
Due to limited financial resources it will not be feasible to
rehabilitate erosion features with large and expensive structures
at a broad/catchment scale. However, it is imperative to minimise
Gullies in theEasternCape, Tsitsavalley.
Tsitsavalleygullies.
Tsitsavalleygullies.
