为了考察中国亚热带不同森林类型对雨雪冰冻灾害的响应模式,以粤北天井山3种代表性的林型一针叶林、阔叶林和混交林为对象,于不同森林类型中比较受损森林与未受损森林在凋落物年产量、成分及月际动态方面的差异,从而在凋落物水平上反映不同森林类型在雨雪冰冻灾害后的早期恢复力.研究结果表明,灾后针叶林、阔叶林和混交林的年凋落量分别为0.52、3.21、1.37 t·hm2,比未受损的同种森林类型年凋落量显著减少,减少程度分别为87.89％、53.46％、76.78％.由此可以看出阔叶林的植被恢复情况最好,说明在凋落物水平上,其灾后恢复的早期阶段恢复力最强.在凋落物成分方面,灾后各森林类型叶凋落物所占比例显著增加,枝凋落物所占比例则显著减少.受损针叶林和阔叶林的凋落物月动态与未受损森林基本一致,但其波动幅度较小；在混交林中,受损和未受损森林其凋落量的季节动态模式则表现出不一致性且为不规则型.根据研究结果,建议在亚热带地区优先考虑种植阔叶林以促进受损森林在类似雨雪冰冻灾害的极端天气后的恢复.%To understand the responses pattern of subtropical forests recovered from the damage of ice storm happened in southern China during Jan to Feb in 2008, we take three different forests, including coniferous forest, mixed forest and broad-leaf forest located in Tianjing Mountain, as a case to compare their differences in annual litter production, component and seasonal fluctuation in undamaged and damaged plots in each forest type and access their recuperability at the early stage of natural recovery. It is indicated that the annual input of litter in the damaged forests was up to 0.52 t·hm-1, 3.21 t·hm-2 and 1.37 t·hm-2 in coniferous forest, broad-leaved forest and mixed forest, respectively. Compared with the normal annual amount of litter in subtropical forest of southern China, it is showed that the total input of litter decreased clearly, which came to 87.89%, 53.46% and 76.78% in coniferous forest, broad-leaved forest and mixed forest, respectively. It is indicated that in the early recovery period, the severer damaged suffer, the less litter produce in the different forest type, which implied the broad-leaved forest has the best recuperability at the early stage of recovery. In addition, the change of components in litter illustrated that the proportion of leaf increased but the branches reduced after the ice storm attack in all forest type. In the case of seasonal fluctuation in litter among different forest type, the pattern between damaged forest and undamaged forest is similar in coniferous forest and broadleaved forest, but it is totally different in the mixed forest. Based on our conclusions, due to the higher resilience and best recuperability, the broad-leaved forest should be served as a preferential choice in forest management to decrease potential impacts of extreme ice storms in subtropical forests.
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