Biopolymer based stabilization of Indian desert soil against wind-induced erosion

Wind-induced soil erosion is a major global misfortune, which obliterates nearly one-third of worldwide soil. The windswept sand particles cover large areas including highways, and make the visibility vague. This results in accidents, damaged infrastructure, delayed flights, and various health issues. The erosive impact of the wind can be minimized by enhancing the intactness of the soil surface. There is a prerequisite to adopt viable measures to strengthen soil against wind erosion. There are certain nature-based solutions that can fortify soil against wind erosion and the application of biopolymers is one of them. The objective of this study is to examine the viability of non-toxic biopolymers for stabilizing desert sand by improving its erosion resistance property and strength. In the present experiment, three biopolymers, sodium alginate (SA), pectin (P), and acacia gum (AG), were used with 1, 2, and 3% concentrations for 1 and 0.75 PV as stabilizing agents. The treatment with biopolymers was performed either by surficial treatment (spraying or pouring of solution) or by mixing and compact method based on the viscosity of prepared biopolymer solutions. The biotreated sand samples were tested in a wind tunnel at varying wind speeds of 10, 20, and 30 m/s to assess sand erosion. Surface strengths were assessed by measuring compressive strength using a pocket penetrometer. Crust thickness measurement was performed to check the penetration depth of biopolymer solution and binding of sand particles. All three biopolymers with 1% concentration gave a feasible solution for erosion against wind and binding of particles through SEM analysis. SA and P could not be sprayed for 2 and 3% concentrations due to high viscosity. This solution is also not feasible for the field application. Simultaneously, AG with 2 and 3% concentration was highly soluble, less viscous, and gave more surface strength due to higher percentage of biopolymer concentration.