闽东沿海防护林台风灾害的影响因子

Factors affecting the typhoon damage to coastal shelterbelt forests in eastern Fujian of East China.

以2010年台风"鲇鱼"(编号1013)为例,调查闽东主要海防林树种台风受灾情况,并对其影响因子进行分析,结果表明:1)不同树种受害程度差异明显,阔叶树种受害重于针叶树种,平均受害级和受害指数分别高出79.1%和76.7%。其中,桉树受灾最重,平均受害级和受害指数分别比湿地松、木麻黄高出90.5%、36.2%和86.7%、36.6%。受灾类型中,折干现象最严重,比例高达40.7%。2)林木不同形态特征受灾程度差异显著,折干类型集中于12～14cm径级,比例为56.8%,倒伏、掘根类型集中10～12cm,比例为57.9%,弯干、断稍现象径级分布较均匀,但同在14cm比例最高,分别为28.6%和18.3%。林木抗风性能与植株尖削度成正相关,而与树高、树冠面积、树冠相对高度成负相关。3)地形条件是影响林木受灾的重要因素,表现为受灾程度迎风坡大于背风坡,陡坡大于缓坡,同一坡向上,迎风坡下腹大于上腹,背风坡正好相反。4)割脂对湿地松抗风性能有较大影响,割脂林木受害指数比未割脂高40.6%,因割脂发生折干植株比例为92.7%。

Taking the typhoon Megi in 2010 as a case,this paper investigated its damage to the main coastal shelterbelt forests in eastern Fujian,and analyzed the related affecting factors.The damaged degree had an obvious difference among the tree species.Broadleaf species were more severely damaged than coniferous species,with the mean damage grade and damage index of broadleaf species being 79.1% and 76.7% higher than those of the coniferous species,respectively.Among the broadleaf species,Eucalyptus received most severe damage,with the mean damage grade and damage index being 90.5% and 36.2%,and 86.7% and 36.6% higher than those of Casuarina and Pinus elliottii,respectively.In terms of damage pattern,stem breakage occurred most commonly,accounting for 40.7% of the total.The trees with different sizes had significant difference in suffering typhoon damage.Stem breakage occurred mostly on the trees at DBH ranging from 12 cm and 14 cm,with a damaged percentage of 56.8%,uprooting occurred mostly on the trees at DBH ranging from 10 cm and 12 cm,with a damaged percentage of 57.9%,while bending and decapitation occurred almost evenly on the trees at different DBH,with a climax at 14 cm,accounting for 28.6% and 18.3%,respectively.Wind-resistance was positively correlated with tree taper,but negatively correlated with tree height,crown area,and crown relative height.Abiotic factors such as topographical condition were another important factors related to typhoon damage.The damage was more severe at windward slope and steep slope than at leeward and gentle slope,and was more severe at slope bottom than at slope top on the windward slope but was reverse on the leeward slope.Resin-tapping had negative effects on the wind-resistance of P.elliottii.The damage index of resin-tapped P.elliottii was 40.6% higher than that of non-tapped trees,and resin-tapped trees received stem breakage at a percentage of 92.7%.