李园节肢动物群落时间动态的聚类分析

为了了解李园节肢动物群落的结构、特征,发挥生态系统中自然因素对害虫的生态调控作用,采用系统调查方法,在分析李园节肢动物群落结构和组织水平的基础上,对李园节肢动物群落的时间动态进行聚类分析,结果表明,对不同时期的总群落、亚群落进行模糊聚类得出结果,总群落的12次调查结果可以聚为5类,D=0.2000,3、11、7和6月初各自归为一类,其余归为一类.天敌亚群落调查结果也聚为5类,D=0.2000,3、7、8月各自归为一类,9月和10月归为一类,其余归为一类.非天敌亚群落调查结果同样聚为5类,D=0.1000,4、7、6、11月各自归为一类,其余归为一类.聚类结果部分反映了群落状况的季节差异,聚类交替现象反映了群落结构复杂性.最优分割结果将总群落、各亚群落均分割为5个阶段,即4月6日为第一阶段,4月27日～6月8日为第二阶段,6月27日～8月27日为第三阶段,9月21日～10月19日为第四阶段,11月22日为第5阶段.反映了各阶段物种种类、数量等其他指标在发生时间上存在的差异.

Cluster analysis on the temporal dynamics of arthropod community in a plum orchard

In this paper,twelve investigations were conducted on the structural feature of arthropod community in a plum orchard,and a cluster analysis was made on the temporal dynamics of the community.The total community could be clustered into 5 clusters (D=0.2000),i.e.,that in March,in June,in July,in November,and in other months.The natural enemy and pest-neutral sub-communities could be also clustered into 5 clusters,respectively.For natural enemy sub-community,the clusters (D=0.2000) were that in March,in July,in August,in September and October,and in other months,and for pest-neutral sub-community,they (D=0.1000) were that in April,in July,in June,in November,and in other months.The results of cluster analysis partly reflected the seasonal differences of total community and sub-communities,while the temporal overlaps of cluster results reflected the complexity of community structure.Based on the optimization cut-apart,both the total community and the sub-communities were divided into 5 stages,i.e.,6 April as the first stage,27 April to 8 June as the second stage,27 June to 27 August as the third stage,21 September to 19 October as the forth stage,and 22 November as the fifth stage.