Drought and root herbivory in understorey Parashorea Kurz (Dipterocarpaceae) seedlings in Borneo
Drought and root herbivory in understorey Parashorea Kurz (Dipterocarpaceae) seedlings in Borneo
复制标题
婆罗洲林下龙脑香科幼苗的干旱和根食草
DOI：
10.1017/s0266467402002511
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发表时间：
2002
影响因子：
1.4
通讯作者：
M. Speight
中科院分区：
文献类型：
--
作者：
D. Bebber;N. Brown;M. Speight
研究了 1997-8 年厄尔尼诺南方涛动期间及之后食草对婆罗洲原始低地森林下层龙脑香树幼苗生长和存活的影响。在干旱期间，鞘翅目（Scolytidae）根蛀虫攻击龙脑香树幼苗，主要是 Parashorea 属的幼苗。侵染在大范围（约 100 m）上具有空间异质性。发病率随受感染地区植物活力的增加而降低。实验表明，干旱条件下根部损伤是致命的，但雨后则不然。落叶和顶端分生组织去除不会增加死亡率。食草动物爆发的时空异质性以及根食草动物实验的困难限制了此类短期调查的力量。然而，研究表明，食草动物会导致物种之间的死亡率差异，因此会影响龙脑香的再生动态。食草的影响取决于受到攻击的植物器官以及与干旱等其他胁迫的相互作用。东南亚雨林中与厄尔尼诺现象相关的干旱越来越频繁，这可能导致食草动物爆发数量增加，并导致幼苗死亡率增加。
The influence of herbivory on dipterocarp seedling growth and survival in Bornean primary lowland forest understorey during and after the 1997–8 El Niño-Southern Oscillation was investigated. During the drought, a coleopteran (Scolytidae) root borer attacked dipterocarp seedlings, primarily of the genus Parashorea. Infestation was spatially heterogeneous on a large (c. 100 m) scale. Attack rate decreased with plant vigour within infested areas. Experiments showed that root damage was fatal under drought conditions, but not after rain. Defoliation and apical meristem removal did not increase mortality. The spatio-temporal heterogeneity of herbivore outbreaks and difficulties involved in experimenting with root herbivores limit the power of such short-term investigations. However, the study shows that herbivores can cause differential mortality between species, and can therefore influence dipterocarp regeneration dynamics. The effect of herbivory depends on the plant organ attacked and interactions with other stresses such as drought. El Niño-related droughts are increasing in frequency in South-East Asian rain forests, which may lead to increased numbers of herbivore outbreaks and greater seedling mortality due to these factors.