年度间同期木槿上节肢动物群落动态及棉蚜分布格局比较

对1999年5月2日和2003年5月1日木槿树节肢动物群落进行调查和分析。结果表明，2003年5月1日的物种丰富度大于1999年5月2日，涉及的分类阶元数前者多于后者；2年间的优势集中性指数、多样性指数、相对丰盛度指数和均匀度指数均略有差异；2年以株为单位，各株4个方位的棉蚜分布格局均为聚集分布；2年以5株总计，4个方位的棉蚜分布趋势也是聚集分布；2年以株为单位的棉蚜水平分布均为聚集格局，但2年间棉蚜数量差异极显著。

Comparison of Trend of Arthropod Community and Distribution Pattern of Aphis gossypii on Hibiscus syriacus between the Same Period of Different Years

Investigation and analysis on the arthropod community on H.syriacus was carried out on May,2,1999 and May,1,2003,respectively,and conclusions were as follows:First,abundance of species and the number of taxonomic categories on May,1,2003 was more than that on May,2,1999;Second,there was a slight difference in dominant concentration index,diversity index,relative abundance index and evenness index between the two years;Third,distribution pattern of A.gossypii with the units of single tree in four directions was aggregation pattern;Fourth,distribution trend of A.gossypii with the units of five trees in four directions was also in aggregation pattern;Last,horizontal distribution pattern of A.gossypii on H.syriacus grown for two years with the unit of single tree was all in aggregation pattern,but the number of A.gossypii on H.syriacus between the same period was of significant difference.