冰雪灾害对杨东山十二度水自然保护区木本植物机械损伤的初步调查

Mechanical Damages to Woody Plants from a Snow Disaster in Yangdongshan Shierdushui Provincial Nature Reserve

在广东乐昌杨东山十二度水省级自然保护区海拔700～1000m的植被群落中设置4个固定样地,研究雨雪冰冻灾害对其木本植物的机械损伤情况,结果表明:1)冰雪灾害对木本植物的机械损伤包括断梢、压弯、断干、翻蔸、倒伏等类型,其中压弯占的比例最高,超过总株数的50%;2)胸径≤3.0cm的林木受危害株数最多,其次是3.1～5.0cm,7.1～9.0cm的株数最少;平均胸径≤5.0cm的林木,主要危害表现为压弯,其他危害类型的平均胸径大多超过5.1cm;3)树高≤5.0m的林木受害较多,翻蔸的平均树高在5.0m以上,5.0m以下的大多是压弯和倒伏,断梢和断干的高度一般在3.1～5.0m之间。

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.