Abstract:
Studies on the effects of off-road driving on
soils were conducted in the Makuleke Contractual Park of
the Kruger National Park. The studies were conducted on
three different soils with different textures and soil compactibilities.
Traffic pressure was applied with a game drive
vehicle loaded with 11 sand bags, each weighing 70 kg.
This gave a total vehicle mass of 3,795 kg, simulating a
vehicle fully laden with tourists. The study included:
(i) comparing of the effects of four different tyre pressures;
(ii) comparing the effects of 1–3 vehicle passes over the
same tyre tracks; (iii) comparison of traffic effects under
dry and wet soil moisture conditions, on soil compaction,
respectively. After each pass penetration resistances were
measured (a) on the tyre tracks, (b) between the tyre tracks
and (c) at different distances outside the tyre tracks. As
expected, vehicular traffic caused soil compaction below
the wheel tracks. Lower tyre pressures caused less compaction
than higher tyre pressures. Fewer vehicle passes
also caused less compaction than more passes on the same
tracks, but most compaction occurred during the first
pass. Thus, driving on the same tracks more than once is
less damaging than driving once on different tracks. Controlled
traffic should be considered when developing
management strategies for off-road driving in wildlife
protected areas.
