A comparative analysis of the sand-trapping potential of two Namib desert shrubs

Abstract

Abstract provided by author:

Sand intrusion from the Namib Sand Sea into the Kuiseb River poses a threat to the economical budget and ecological use of the river. This problem is associated with the mobility of sand particles by winds

The present study reports the results that were obtained from quantitative observations of sand movement around Salvadora persica and !Nara (Acanthosicyos horrida) plant species. This case study was done at Gobabeb in the Central Namib Desert. The sand-trapping potential of the two Namib Desert shrubs were analysed and compared in terms of their effectiveness in enhancing sand accretion. Wind-, humidity-, and sand measurements demonstrate that !Nara (Acanthosicyos horrida) accretes sand more effectively than Salvadora persica

By assuming that decreasing wind velocity causes sand accretion around the plants, a simple quantitative model of vegetated dune dynamics is postulated. Maintenance of vegetated dune dimension, height and width, is seen as a response to the pattern of the reciprocative behaviour of wind velocity and humidity change. It is recommended that a further investigation should be made to determine which of the two plant species stabilize sand more effectively. Such results may be of use in the monitoring processes of sand movement in deserts