林丹烟剂对毛竹林冠与林下层节肢动物共有种及其多样性的影响

共有种反映毗邻生境节肢动物群落的相互作用程度及其潜在互作途径的多样性.通过对施用林丹烟剂后毛竹林冠层与林下层节肢动物的系统定位调查,分析和比较了林丹烟剂干扰下两个林层的节肢动物共有种及其多样性.结果表明,以未防治和白僵菌防治为对照,施用林丹烟剂显著减少了林冠和林下层的共有种及其个体数,降低了两个林层中共有种的多样性;在物种方面主要表现为蜘蛛目、膜翅目、鞘翅目、双翅目和鳞翅目共有种减少;在个体方面,林下层主要表现为蜘蛛目、膜翅目、鞘翅目和双翅目共有种个体减少,林冠层主要表现为蜘蛛目、鞘翅目和双翅目共有种个体减少.但无论在物种还是个体方面,林丹烟剂对捕食性共有种的影响均最大.进一步的灰色关联分析表明,引起共有种多样性下降的主要原因在于共有物种的减少.因此认为,林丹烟剂干扰削弱了林下和林冠层节肢动物之间的相互作用,不利于林下生境促进林冠层生物多样性和增强群落对叶部害虫自然控制作用等生态功能的发挥.图1表6参22

Effect of Lindane on Common Species and Diversity of Arthropod in Canopy and Understory of Phyllostachys heterocycla cv. pubescens Forest

Common species generally imply the interacting intensity and approaches in two arthropod communities in different types of abutting habitats. Based on the systematic survey in the selected bamboo forest stands of Phyllostachys heterocycla cv. pubescens (Mazel) Ohwi in Sanming, Fujian during 2001-2002, the arthropod common species between the understory and canopy of the forest were disturbed by the pesticide of Lindane, and their distribution characteristics were compared and analyzed. The results showed that the number and individuals of the common species were decreased significantly in the forest under the disturbance of Lindane compared with those in the forest without any interference of pest control activities or only with the agent of Beauveria sp. The disappearing common species mainly belonged to Arancuda, Hymenoptera, Coleoptera, Diptera and Lepidoptera. The common species with their individuals decreasing mainly belonged to Arancuda, Hymenoptera, Coleoptera and Diptera in the understory, and Arancuda, Hymenoptera and Diptera in the canopy. Especially, the populations of predatory arthropod common species were mostly affected by the use of Lindane. Furthermore, grey correlation analysis indicated that the decrease in diversity of the common species was mainly due to the loss of common species. Therefore, it was concluded that the interaction of arthropods between the understory and canopy of the forest became weakened because of Lindane, which was unfavorable to the promotion of the understory habitat for the biodiversity in the canopy of the forest, and to the natural control of pests in the bamboo leaves. Fig 1 , Tab 6, Ref 22