Fruit sizes and the structure of frugivorous communities in a New Guinea lowland rainforest
Fruit sizes and the structure of frugivorous communities in a New Guinea lowland rainforest
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新几内亚低地雨林的果实大小和食果群落结构
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发表时间：
2016
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通讯作者：
V. Novotný
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作者：
R. Čtvrtečka;K. Sam;S. Miller;G. Weiblen;V. Novotný
短句来源对巴布亚新几内亚低地雨林326种木本植物（鞘翅目、鳞翅目、双翅目，除果蝇科外）共3目25 565只昆虫进行了饲养研究。19.3%的植物果实不受任何目昆虫的侵害，33.4%的植物果实受到单一目昆虫的侵害，30%的植物果实受到两个目昆虫的侵害，17.2%的植物果实受到三个目昆虫的侵害。受到单目昆虫攻击的可能性是正相关的，因此，比预期更高比例的植物物种要么完全没有受到攻击，要么被所有三目昆虫攻击。大多数植物种类的果实均表现出低攻击率和低昆虫密度。每公斤水果平均被11只昆虫袭击，其中包括3到4只鞘翅目昆虫、6只双翅目昆虫和1只鳞翅目昆虫。因此，我们平均从10个果实中饲养1只昆虫，其中从14个果实中饲养1只双翅目昆虫，从22个果实中饲养1只鞘翅目昆虫，从100个果实中饲养1只鳞翅目昆虫。326种植物中只有72种每10个果实含有1只以上昆虫，只有7种每10个果实含有1只以上昆虫。我们的研究结果表明，专门的昆虫种子捕食者可能过于稀少，无法通过密度依赖的种子死亡率来维持植被的多样性，正如Janzen-Connell假说所建议的那样。果实重量、果实体积、中果皮体积、种子体积和肉质对果实被食虫昆虫攻击的概率无显著影响。而双翅目侵食的果实体积较大，中果皮和种子体积均大于鞘翅目和鳞翅目侵食的果实。
A community of frugivorous insects was studied by rearing of 25 565 individual insects representing three orders (Coleoptera, Lepidoptera and Diptera except Drosophilidae) from 326 woody plant species in a lowland rainforest in Papua New Guinea. Fruits from 19.3% of plant species were not attacked by any insect order, 33.4% of plant species were attacked by a single order, 30% by two orders and 17.2% by all three orders. The likelihood of attack by individual orders was positively correlated so that a higher proportion of plant species than expected suffered either no attack at all or was attacked by all three insect orders. Fruits from most of the plant species exhibited low rates of attack and low densities of insects. One kilogram of fruit was attacked on average by 11 insects, including three to four Coleoptera, six Diptera and one Lepidoptera. Thus, we reared on average one insect from 10 fruits, including one Diptera from 14 fruits, one Coleoptera from 22 fruits and one Lepidoptera from 100 fruits. Only 72 out of the 326 plant species hosted more than one insect per 10 fruits, and only seven species supported a density of greater than one insect per fruit. Our results suggest that specialized insect seed predators are probably too rare to maintain the diversity of vegetation by density-dependent mortality of seeds as suggested by the Janzen–Connell hypothesis. Fruit weight, fruit volume, mesocarp volume, seed volume and fleshiness had no significant effect on the probability that a fruit would be attacked by an insect frugivore. However, fruits attacked by Diptera were significantly larger and had larger volume of both mesocarp and seeds than fruits attacked by Coleoptera and Lepidoptera.