Aggregate-Breaking Mechanism Response to Polyacrylamide Application of Purple Soils in Southwestern China Using Le Bissonnais Method

Polyacrylamide (PAM) is a water-soluble polymer with strong cohesiveness and water absorption capacity, it has been widely used to modify soil structural stability. However, little information available on the impact of PAM application aggregate-breaking process purple soils in hilly areas southwestern China. Therefore, current study aimed examine influence aggregate stability terms different breakdown mechanisms at hillslope locations. Three disruptive tests employing Le Bissonnais method (FW, fast-wetting sieving; SW, slow-wetting WS, wet-stirring sieving) were determine mean weight diameter (MWD), geometric (GMD), mass fractal dimension (D) aggregates, erodibility factor (K) was calculated as an index anti-erodibility. Overall, major mechanism for following: SW (differential swelling) > WS (mechanical breakdown) FW (slaking). The content water-stable aggregates (>0.25 mm) obviously rose after application, most significant influences shown under FW. A difference MWD observed between without polyacrylamide (CK) (p < 0.05). there GMD CK 0.05) SW. In comparison CK, D value significantly reduced, mainly slope locations 0 20 m. descending order FW, found basis K These findings contribute improved understanding proper amendments control loss soils.