摘要：Catastrophic mudflows and landslides triggered by rainfall can occur suddenly and move with high
speed, damaging electrical and civil infrastructure and threatening human and wildlife. Due to the climate
change and extreme weather increase, it is likely that wildfires and consequently mudflows will increase in
frequency in the future. The risk of mudflows and landslides increases in post-wildfire areas mainly because of
water repellent soil which forms on slopes. Water repellency, or hydrophobicity, can occur due to the burning
of the accumulated organic matter in soil. Hydrophobicity repels water and prevents infiltration of water into
the soil, which results in soil erosion, mudflows and landslides. In this study, a series of experimental
laboratory tests are conducted on regular, hydrophobic and Xanthan gum-treated hydrophobic sand. Xanthan
gum, which is an environmentally friendly biopolymer, can be substituted for chemical material used for soil
improvement and decrease the CO2 emissions and enhance environmental slope protection. Xanthan gum can
enhance the inter-particle cohesion and can hold a large amount of water and consequently help the recovery
of the vegetation. Contact angle, direct shear and rain simulation tests are conducted on samples. Results show
that in Xanthan gum treated slope the rate of erosion and the risk of mudflow decreases. It is also observed that
the Xanthan gum treated sample can retain more water and consequently decreases the rate of wind erosion
and helps the dust-control in burned areas.
