化防田与综防田蜘蛛群落物种组成及优势类群动态分析

洞庭湖平原地区共有稻田蜘蛛10科27属41种，其优势种为拟水狼蛛、食虫沟瘤蛛、八斑鞘腹蛛和锥腹肖蛸。在两类防治田的早稻田中，蜘蛛优势种没有变化，主要为拟水狼蛛和食虫沟瘤蛛；晚稻田中，蜘蛛优势种存在更替现象。在综防田和化防田中，蜘蛛种类和个体数量存在较大差异。同时，对蜘蛛控制害虫生物量进行了定量测定。

On the Species Component in Spider Community of Paddy Field and the Dynamics of the Dominant Species in Different Fields

From May to November in 2002 a thorough investigation was made on species component and dynamic characteristics of spider community of paddy fields in Dongting Lake's Plain. 41 species of spider belong to 27 genera and 10 families have been found in the rice field. The dominant families are Lycosidae, Liniphiidae, Theridiidae and Tetragnathidae; and the dominant species are Pirata subpiraticus, Ummeliata insecticeps, Coleosoma octomaculatum and Tetragnatha maxillosa. In the two types of early rice fields with different controlling methods, P. subpiraticus and U. insecticeps are the dominant species. In the late rice fields, alternation of the dominant species has been found, and an attempt is made for explaining it. The species and the number of spiders in the two kinds of fields (integrated management or chemical control) differ from each other obviously. The biomass of pests controlled by spiders was determined quantitatively.