西双版纳奇楠沉香林昆虫群落结构与功能研究

Research on the Structure and Function of Insect Communities in Aquilaria crassna Forest of Xishuangbanna

奇楠沉香Aquilaria crassna Lecomte是西双版纳引种栽培的一种名贵药用植物。它与昆虫的相互关系对其生长和生物多样性保护具有重要意义。本文采用灯诱法研究沉香林的昆虫群落结构与功能,诱捕到的昆虫隶属13个营养生态位集团,涉及13目67科198属216种,其中98种取食植物叶片,31种刺吸植物汁液,30种捕食其他昆虫,15种取食植物花、芽、果,10种取食腐烂物,9种钻蛀植物茎干,9种为地下昆虫,9种寄生其他昆虫,5种取食苔藓,4种取食植物花蜜,3种取食粪,2种传授植物花粉,2种取食腐木;对奇楠沉香造成严重危害的是黄野螟Heortia vitessoides、毛角薄翅天牛Megopis marginalis,其次是宽带鹿花金龟Dicronocephalus adamsi、三带瘦花金龟Coilodera ornata。个体数量以鞘翅目最多,鳞翅目次之,革翅目最少;物种数以鳞翅目最多,鞘翅目次之,缨翅目最少。样地内各月份物种多样性指数与物种丰富度排序为5月下旬>6月上旬>6月中旬>6月下旬>7月上旬>5月中旬>7月中旬>5月上旬。昆虫群落的组成与沉香林物候关系密切,在奇楠沉香开花结果的高峰期,昆虫群落呈现出多样性高而均匀度低的分布格局。在一定程度上,捕食与寄生昆虫控制了林内害虫;食粪与腐烂物、食腐木与苔藓昆虫分解了林内有机物,促进了生态系统的物质循环。

Aquilaria crassna Lecomte is an introduced precious medicinal plant in Xishuangbanna. The relationship between A. crassna and insects is important to biodiversity conservation. Trapping light method was used to study the structure and function of insect community in A. crassna forest. A total of 216 insect species belonging to 198 genera,67 families and13 orders were trapped. Among them,13 trophic groups were recorded,including： leaf-feeding（ 98 species）,juice-sucking（ 31 species）,predators（ 30 species）,blossom bud fruit-feeding（ 15 species）,decay-feeding（ 10 species）,stem-drillers（ 9 species）,underground（ 9 species）,parasites（ 9 species）,moss-feeding（ 5 species）,nectar-feeding（ 4species）,feces-feeding（ 3 species）,pollinators（ 2 species）,and rottenwood-feeding（ 2 species）. The most serious damage to A. crassna was caused by Heortia vitessoides and Megopis marginali. The order Coleoptera was the most abundant in terms of individuals followed by Lepidoptera. Moreover,Holotrichia parallela was the dominant species. Species richness decreased in the following time sequence： late May,early June,middle June,late June,early July,middle May,middle July and early May. There was a close relationship between the composition of insect community and the phenological stages of A. crassna. During the peak time of flower and fruit abundance,the parameter of species diversity increased,and the parameter of evenness decreased. To some extent,predators and parasites insects may control the number of pests. Fecesfeeding,decay-feeding,rottenwood-feeding and moss-feeding decomposed organism may promote material cycle of the ecosystem in the A. crassna forest.