冰雪灾害对3种不同林分的损害特征比较

Comparison Between Characteristics of Ice Damage to Three Stands

通过调查广东北部受冰雪灾害地区的湿地松、阔叶林和杉木林3种林分,比较了不同树种组成的林分在冰雪灾害下的受害特征.研究表明:林木受害类型可分为折断、弯曲、倒伏和断头4种类型;湿地松林折断的树木最多,占88%;阔叶林折断的树木占64%;杉木林没有弯曲和倒伏的树木,基本是折断和断头的类型.胸径在9.0 cm以下的杉木多数容易发生折断,而胸径在9.0 cm以上的杉木则多数容易发生断头.杉木与湿地松受害特征不同,杉木断干高较高些,而湿地松则容易在低处折断.不同林分生物量的总损失量排序为:阔叶林>湿地松林>杉木林.

The stands of Pinus elliottii, broadleaved forest and Cunninghamia laneeolata were investigated to compare their characteristics suffering from ice damage. The characteristics of ice damage were different because the structure and tree species in the stands were quite different. Study results indicated that there were four types of damage to the trees of the stands, including broken-off, bent,lodging and beheaded. In the Pinus elliottii stand, the largest number of damaged trees was the broken-off trees, accounting for 88% of the total, while in the broadleaved stand, the broken-off ones made up 64%. In the Cunninghamia lanceolata stands, damaged trees were almost broken-off and beheaded trees,without bent and lodging ones. The trees with a diameter at breast height （DBH） below 9.0 cm were mostly damaged by the broken-off while those with DBH over 9.0 cm were mostly damaged by the beheaded obviously. The damaged characteristics of Cunninghamia laneeolata were quite different from Pinus elliottii. The former broke off at higher point of stem, whereas the latter broke off at the low point of stem. Results also showed that the amount of lost biomass of the three stands was in the following order：broadleaved stand 〉 Cunninghamia laneeolata stand 〉 Pinus elliotti stand.