毛竹受雨雪冰冻危害的受损特点

通过对浙江省遂昌县受雨雪冰冻危害的毛竹Phyllostachys pubescens林受损特点分析,旨在为今后的毛竹科学经营提供依据。结果显示：①海拔为400～750m时,毛竹受损率达50%以上,受损最严重。②坡度与受损率成正比关系,y=1.3011x-1.0714,坡度〈30°可减少雨雪冰冻的危害;③经营措施为全面土壤深挖20cm以上的毛竹林的爆裂率极显著低于药剂除草的毛竹林,t=16.251〉t（5）0.01（4.032）;④不同龄级毛竹间受损率存在极显著差异,进一步进行Q检验发现,Ⅰ度竹（1～2年生）受损率极显著低于Ⅲ度（5～6年生）竹,D=18.64〉D0.01（15.7215）,显著低于Ⅱ度（3～4年生）竹,D=13.43〉D0.05（11.6307）;⑤立竹结构比例以Ⅰ度∶Ⅱ度∶Ⅲ度∶Ⅳ度（7～8年生）=3∶3∶3∶1对抗雨雪冰冻灾害最有利。图2表6参8

Damage characteristics of Phyllostachys pubescens forest in freezing rain and snow hazards

From January to February in 2008, main areas of China subjected to freezing rain and snow hazards. We investigated the damage in Phyllostachys pubescens （moso bamboo） forests in Suichang County of Zhejiang Province in the late of February, in order to provide reasonable basis for management of moso bamboo forests. The analysis of moso bamboos damage characteristics in freezing rain and snow hazards indicated that： ① The damage rate was above 50% when the altitude was between 400 - 700 m. ② Gradient and damage rate formed a direct proportional relationship as y = 1.301 1x - 1.071 4. The damage rate de- creased when gradient was lower than 30°.③The breaking rates of moso bamboo forest treated with over 20 cm comprehensive digging were significantly （P〈0.01）higher than that of chemical weeding. ④There were significant difference in different age classes. Through Q-test, 1 - 2 years old bamboo （ I phase）＇s damage rate was significantly higher than 3 - 4 years old bamboo （ Ⅱ phase）＇s damage rate D = 13.43 〉D0.05 （11.630 7）land 5 - 6 years old bamboo （Ⅱ phase）＇s damage rate D = 18.64〉D0.01 （15.72）]. ⑤ In the age structure, the portion of I ：Ⅱ ： Ⅱ ： Ⅳ （7 - 8 years old） = 3 ： 3 ： 3 ： 1 was reasonable for defense a- gainst freezing rain and snow hazards. Ch, 2 fig. 6 tab. 8 ref.]