溴氰菊酯对马尾松林昆虫群落多样性的影响

Effects of Deltamethrin on the Insect Community Diversity of Masson's Pine Stands

１９９５年７月至１９９６年６月，在湘中丘陵区马尾松林内用溴氰菊酯进行喷药防治害虫试验结果表明，溴氰菊酯对林内昆虫群落的物种丰富度和多样性均有影响．其中植食类群受影响的主要是同翅目、直翅目、鳞翅目、鞘翅目和半翅目昆虫，捕食类群主要是蚂蚁和蜘蛛．在药剂作用下，植食类群和寄生类群的物种丰富度及多样性水平均呈现下降，捕食类群的物种丰富度虽有所下降，但在整个群落中所占的比例及多样性水平均有较大程度的上升．施用溴氰菊酯可降低植食物种的优势度，提高天敌类群与植食类群之比值，使昆虫群落在一定时间内保持相对稳定．但它降低了群落内物种的丰富度（特别是稀有种和偶见种）及多样性水平，因此在生产上用其防治松林害虫时不宜在大面积范围内长期使用．

From July, 1995 to June, 1996, the effects of deltamethrin on the insect community diversity were studied in masson's pine( Pinus massoniana )stands in the central hills of Hunan province. The results indicate that deltamethrin has a large influence on the species abundance and diversity degree of the insect community of masson's pine stands. The influenced insect species in phytophagous group mainly belong to Homoptera, Orthoptera, Lepidoptera, Coleoptera and Heminoptera, and those in predatory group are mainly ant and spider. In the action of deltamethrin, the species abundance and diversity degree of phytophagous and parasitic groups decrease. Although the species abundance of predatory group also decreases to some degree , the ratio of species and individual in the insect community and the diversity degree have a large increase. After applying deltamethrin, the superiority degree of phytophagous insect species declines, the ratio of natural enemy insect group to phytophagous insect group goes up, and the insect community in the masson's pine stands maintains relative stability in a certain period. However, because the application of deltamethrin will decrease the species abundance (especially rare species) and the diversity level of insect community, it is inadvisable to apply this pesticide to control pests over a long period of time in a large range of masson's pine stands.