Abstract: After a severe wind/snow disaster in January 2022, we conducted a survey of the damage of Juglans regia in different slope aspects in Xinjiang Wild Walnut Nature Reserve. The distribution characteristics of different damage grades of J. regia were analyzed, and the influence of tree growth characteristics and slope aspect on the damage grades was explored. The results showed that: (1) 561 individuals had different degrees of damage in the reserve. The number of the damaged individuals of J. regia was in the following order: Grade Ⅳ (20) < Grade Ⅴ (95) < Grade Ⅲ (101) < Grade Ⅱ (150) < Grade Ⅰ (215). The damaged individuals at grades I to III accounted for 83.07% of the total damaged individuals. (2) With the increases of DBH and height classes, the proportions of damaged individuals increased sharply, decreased sharply, and then remained stable. The damaged trees of grade Ⅰ had the highest average DBH and height, which showed significant difference with other four damage grades. (3) The damage rate of different slope aspects was in order of semi-sunny slope (17.11%), sunny slope (18.54%), shady slope (29.59%), and semi-shady slope (34.76%). Grades Ⅰ to Ⅱ mainly occurred on semi-shady slope, while Grades Ⅲ to Ⅴ mainly occurred on shady slope. In the four slope aspects, there was no significant difference in the proportion of damaged individuals at the same damage grade (P>0.05). (4) DBH and height of J. regia and their interaction had significant effects on damage grades (P<0.05), but the damage grade was not significantly affected by slope aspect (P>0.05). Our results can provide scientific reference for the management and protection of J. regia in sudden wind/snow disaster.

Key words: Juglans regia, wind/snow disaster, damage grade, tree growth characteristics, slope aspect