不同生境条件与管理方式对茶园蜘蛛群落结构及多样性的影响

蜘蛛在茶园的生态控制和生物防治中起到重要的作用,为了解不同生境条件和管理方式的茶园蜘蛛群落结构差异和多样性变化,于2011年3月份—2011年10月份,运用振落承接和过筛法对3种不同类型茶园的蜘蛛群落组成与多样性进行了调查。结果表明:(1)3种类型茶园蜘蛛群落组成:3种类型茶园蜘蛛群落在科、属、种的组成及个体数量上,均表现为有机茶园高,无公害茶园次之,普通茶园低,且在物种数和个体数存在显著差异。管巢蛛科和狼蛛科是3种类型茶园的优势类群,球蛛科、跳蛛科、狼蛛科、皿蛛科的物种优势度大于10%。(2)蜘蛛群落物种多样性的多重分析结果表明,有机茶园蜘蛛群落的个体数、物种数、物种多样性指数、物种丰富度指数和均匀度指数均高于无公害茶园和普通茶园,普通茶园最低,且达到显著水平(P0.05)。(3)多元数据分析结果表明,有机茶园蜘蛛群落组成与普通茶园差异较大,无公害茶园与普通茶园蜘蛛群落组成差异较小;3种类型茶园的茶丛蜘蛛群落个体数、物种数及物种多样性指数、丰富度指数和均匀度指数均高于地表,且表现为机茶园多,无公害茶园次之,普通茶园最少。蜘蛛的功能群采集发现,在3种茶园中结网蜘蛛少,而主要是游猎蜘蛛。(4)不使用化学农药的茶园,因其周边生境结构复杂(竹林、小灌木及杂草),植被丰富,形成植被缓冲带,改善了茶园小气候环境,增加了茶园土表覆盖度,可明显提高茶丛和地表游猎蜘蛛的物种数和个体数量。综合研究结果表明,在生态条件好、干扰少的有机茶园中的蜘蛛物种数量、群落多样性明显高于受损生态系统和人为干扰强的普通茶园。

Effects of different habitats and management on the spider communities in tea plantations

Spiders play an important role in ecological management and biological control in tea plantations. To better understand differences in the community structure and species diversity in different tea plantations with different habitats and management, three types of tea gardens, i.e., organic, pollution-free, and common gardens, were investigated using vibration and sieving methods to collect falling spiders. A total of 16952 spider specimens that belong to 75 species, 68 genera, and 21 families were collected; 47.72% (20 families and 67 genera) of 8089 specimens were collected from the organic tea garden; 29.60% (20 families and 54 genera) of 5017 specimens, pollution-free tea garden; and 18.10% (18 families and 47 genera) of 3068 specimens, common tea garden. The order of the spider community composition and individuals, from high to low, was as follows:organic tea garden, pollution-free tea garden, and common tea garden. The differences in species diversity and individual numbers were significant among the three types of tea gardens. Clubionidae and Lycosidae were the dominant taxa, and species dominance in Theridiidae, Salticidae, Lycosidae, and Linyphiidae was greater than 10%. The multiple analysis results showed that individual number, species number, species diversity index, species richness index, and evenness index of the spider community were higher in the organic tea garden than in the pollution-free and common tea gardens; the common tea garden showed the lowest values (P < 0.05). Multivariate data analysis showed that the obvious differences in spider community composition between the organic tea garden and common tea garden were large; however, the differences between the pollution-free tea garden and common tea garden were few. In the three types of tea gardens, individual number, species number, species diversity index, richness index, and evenness index were higher in the tea bushes than on the surface, and the order was as follows:organic tea garden, pollution-free tea garden, and common tea garden. Less netting spiders and more wandering spiders were found in the three types of tea plantations. Without the use of chemical pesticides in tea gardens, the complex surrounding habitat and rich vegetation (bamboo, small shrubs, and weeds) could increase species and individual numbers of hunting spiders in tea bushes and the ground, forming an effective buffer zone to improve the microclimate environment and to increase soil surface coverage significantly. In conclusion, the species number and community diversity in organic tea gardens with fine ecological conditions and low human disturbance are obviously higher than those in common tea plantations with a damaged ecosystem and high human disturbance.