Abstract
Dust control and air quality are major environmental concerns, especially in arid regions. Several techniques have been developed in the past to control dust; however, several weaknesses of these techniques, including being short term, having a high cost, and toxicity in several cases, have been reported. This paper investigates the use of agriculturally derived (non-toxic) biopolymers to stabilize sand against wind-induced erosion. Three naturally occurring biopolymers, namely, acacia gum (AC), sodium alginate (SA), and pectin (PT), were used as stabilizing agents at varying concentrations. Wind tunnel laboratory experiments and penetration tests were used to evaluate the erosion resistance and the soil surface crust strength of sand treated with these biopolymers. The experimental results showed that the application of the proposed biopolymers, in general, significantly increased the resistance of dune sand exposed to wind speeds of up to 16.2 m/s compared to untreated sand or sand treated with water. The crust penetration resistance for soil treated with AC was observed to increase with increasing biopolymer concentration, whereas that of soil treated with SA and PT was found to reach a maximum at a concentration of 2%. Soil treated with SA and PT biopolymers showed remarkable resistance to wetting–drying cycles. However, soil treated with the AC biopolymer only showed durable resistance to wetting–drying cycles at concentrations of 3% and 5%. At a concentration of less than 3%, the soil loss rate was higher. Scanning electron microscopy images revealed that the sand particles were effectively bonded at their contacts and that the pores were filled with the biopolymers, which improved the crack and erosion resistance of the treated sand against wind erosion.