The effect of tourist roads development on road-side vegetation and soils within the Etosha national park

Abstract

Management of tourism-based protected areas is often faced with a challenge of balancing nature conservation and tourism development. Understanding such interactions is crucial for resources management in tourism-based conservation hotspots such as Etosha National Park (ENP). This study assessed how roads, being part of tourism development, impacts on conservation efforts in ENP, focusing specifically on the roadside landscape, vegetation and soils. Data was collected at at 30 selected sites in major vegetation communities within the park. Herbaceous biomass was assessed using a Disk Pasture Meter based on field calibration from ENP. Soil samples were collected using a soil auger and analyzed. Results show that a substantial network of tourist roads has been developed for Etosha National Park, translating in a road density of 0.2 km/km2. The development of this road network has left more than 180 unrestored gravel pits, or an average of one gravel pit for every 4 km. Similarly, results demonstrated that roads and related vehicular activities have significant impact on the foliage cover and biomass yield of herbaceous species adjacent to the roads, with foliage cover decreasing with increasing proximity to roads. No conclusive evidence emerged to suggest that roads and vehicular emission have a significant impact on roadside soil chemical properties. An exception is made to elevated calcium, carbonate and high cation exchange capacity which is speculated to have been sourced from the Etosha limestone. This study concluded that an unrestricted development of roads and the accompanying quarrying of gravels have a potential to degrade the landscape of Etosha National Park. As a first attempt, this study serves as a baseline for monitoring tourism related ecological disturbances in the park.