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Accueil du site → Master → Afrique du Sud → 1997 → Off-road vehicle perturbation effects on the geomorphic environment of Golden Gates Highlands National Park, South Africa

University of KwaZulu-Natal (1997)

Off-road vehicle perturbation effects on the geomorphic environment of Golden Gates Highlands National Park, South Africa

Moodley M

Titre : Off-road vehicle perturbation effects on the geomorphic environment of Golden Gates Highlands National Park, South Africa

Auteur : Moodley M

Université de soutenance : University of KwaZulu-Natal

Grade : Master of Science (MS) 1997

Résumé
The paucity of access roads serving many mountainous regions of Southern Africa has, in recent years, prompted the widespread use of off-road vehicles to solve mobility constraints. Despite the obvious advantages of motorised transport, the impact of vehicles on the geomorphic environment remains poorly understood. An investigation of the geomorphological changes that occurred on management related off- road vehicle trails within the semi-arid mountainous Golden Gate Highlands National Park was undertaken. The study showed that off-road driving impacted negatively on the geomorphic environment by destroying the vegetation cover, compacting the soil and smoothening surface roughness elements. Bulk density and shear strength for the modified soil increased significantly with a corresponding decrease in aggregate stability and infiltration rates. Changes to the chemical properties of the soil were "inter alia" a loss of organic matter, an increase in the clay dispersion percentage and a higher exchangeable sodium percentage. The nett effect of these changes was to alter the hydrogeomorphological functioning of the impacted areas such that the modified conditions favoured accelerated soil erosion. On steep hill-climbs, rills and gullies have developed in response to the concentration of overland flow within vehicle ruts. Sheet-wash related degradation was the major erosion form active within the inter-rut zone. The nett effects of these changes were an increase in erosion rates, destabilisation of the landscape and a compromise in the aesthetic quality of the area.

Présentation (NRF)

Page publiée le 21 octobre 2017