Abstract: To understand the water holding capacity of woody debris in the riparian zone of subalpine forest, water absorption process and water holding capacity of S alix paraplesia woody debris with six different diameter classes (>30, 30-20, 20-10, 10-5, 5-2 and 2-1 cm) were measured in the subalpine riparian zone of Wanglang National Nature Reserve by water immersion method. The results showed that the maximum water holding capacity across all diameter classes varied from 1024.78 to 2674.67 g·kg^-1. Water holding capacity from high to low was in order of 10-5, 20-10, 30-20, >30, 2-1, and 5-2 cm. The saturated water content increased over time during the process of water absorption, and the water absorption rate decreased. Woody debris with 30-5 cm diameter classes had good water holding capacity and water absorption capacity. In conclusion, retention of woody debris with larger diameter in the riparian zone is beneficial to improving the function of water conservation.

Key words: landscape gradient., evolution of patterns, wetland landscape, grid transformation