关键词: 冰雪灾害, 杨东山十二度水省级自然保护区, 木本植物, 机械损伤

Abstract: The mechanical damages to woody plants in Yangdongshan Shierdushui Provincial Nature Reserve,Lechang of Guangdong Province resulting from a snow disaster were investigated by sampling four 50 m×30 m plots located from 700 m to 1 000 m of elevation.in Shierdushui area of the reserve.The results showed that the woody plants suffered from five modes of damages:top breakage,stem bending,trunk breakage,uprooting and lodging.Stem bending was the prevailing mode of damage with an average of over 50% of damaged plants recorded in the four plots.The highest proportion of damaged plants in regard to DBH was recorded in the ≤3.0 cm DBH class,followed by the 3.1～5.0 cm DBH class,while the lowest found in the 7.1-9.0 cm DBH class.The mode of stem bending was mostly found in woody plants with mean DBH≤5.0 cm,while the other modes of damages were recorded in plants with mean DBH exceeding 5.1 cm.The woody plants with heights ≤5.0 m exhibited the most serious damage.In regard to the mode of damages,uprooting mostly occurred in plants with a mean height <5.0 m and stem bending and lodging in plants with a mean height less than 5.0 m.The mean height of top and trunk broken plants was from 3.1 m to 5.0 m.

Key words: snow disaster, Yangdongshan Shierdushui Provincial Nature Reserve, woody plants, mechanical damage