湖南地区桑园害虫-天敌群落结构及季节动态研究

Studies on the Community Structures and Seasonal Dynamics of Mulberry Insect Pest-natural Enemies

基于对湖南地区桑园害虫-天敌群落的系统调查,应用群落参数和系统聚类的方法分析了桑园害虫-天敌群落结构及季节动态。桑园害虫-天敌群落多样性指数全年存在较大的差异,均匀度指数也极不一致,害虫亚群落一直保持很高的物种丰富度和群落生态优势度,少数几种害虫的种群优势度特别大。桑园害虫-天敌群落还呈现明显的季节消长规律,全年基本上呈单峰曲线,与月均温度曲线基本一致,且与桑叶采伐、农药治虫、月降雨量等密切相关,并表现出天敌-害虫-桑树之间明显的追随现象。桑园害虫-天敌群落季节动态可分为:越冬期、活跃期、波动期和过渡期4个阶段。

Based on the systematic surveys of mulberry in Hunan region, the community structures and seasonal dynamics of mulberry insect pest-natural enemies were analyzed by the methods of community parameters and systematic cluster. The community diversity index and community evenness index of mulberry pest-natural enemies were greatly differ from months. Mulberry pest sub-communities always remained in very high level of species abundance and predominance of community zoology in the whole year. A few of pests showed distinct predominance. The amount and species of mulberry pests and natural enemies also revealed the obvious seasonal ebb and flow law, basically presenting a single-aped curve in the whole year, in accordance with the curve of month-average temperature. And it correlated to the plucking of mulberry leaves, pesticide application, month-rainfall, and so on, representing the obvious pursuing phenomenate among mulberry-pest-natural enemies. The seasonal dynamics of mulberry insect pest-natural enemies were divided into four stages： rest, activity, fluctuating and transition period.