Eco-friendly Improvement of Water Erosion Resistance of Unstable Soils with Biodegradable Polymers

The improvement of water erosion resistance of soils is gaining the attention of the scientific community. Erosion represents a threat to agricultural productivity because of the loss of valuable superficial soil and nutrients. Cultivation soils erosion is one of the main contributors to the desertification process, which is, itself, a global problem. Recently, polysaccharides have been tested as additives to improve earth construction materials with respect to their mechanical properties and water erosion resistance. This paper studies the use of biodegradable polymers to improve soil stabilization with respect to erosion by water. Aqueous solutions of the polysaccharides chitosan and carrageenan were used to improve wettability and runoff resistance of sandy and loose soils. Chitosan becomes positively charged when dissolved in dilute acidic solutions, while carrageenan becomes negatively charged. Their capacity to form polyelectrolytes in aqueous solutions may be a contributor in retaining cohesiveness in loose soils.