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将苹果树分为 1 8个区 ,研究每个区立体空间中的昆虫群落结构。结果表明 :苹果树中昆虫 (及螨类 )共有 2 7种 ,其中植食性害虫 1 5种 ,种数占总量的 5 5 .5 6% ,天敌昆虫 1 2种 ,占 44.44% ;昆虫群落在树上、下、中及内外层差异大 ,而在东、南、西、北 4方位上差异小。通过频次比较的方法与χ2 检验得出 :梨星毛虫、山楂叶螨、顶梢卷叶蛾均符合负二项分布 ;采用聚集指标法计算得出 :梨星毛虫、山楂叶螨、顶梢卷叶蛾均为聚集型分布 ,另外 ,山楂叶螨的 I值最大 ,聚集度最高。
The apple tree is divided into 18 districts to study the insect community structure in the three-dimensional space of each district. The results showed that there were 27 species of insects (including mites) in apple trees, including 15 species of herbivorous pests, accounting for 55.65% of the total and 12 species of natural enemies, accounting for 44.44% of the total. Insect communities In the tree, under, middle and outer differences, but in the east, south, west and north 4 position difference is small. By means of frequency comparison and chi-square test, the results showed that the pear-shaped caterpillars, the hawthorn spider mites and the tip-rolled leaf moths all fit the negative binomial distribution. The aggregation index method was used to calculate that the pear-shaped caterpillars, hawthorn spider mites, Aggregate distribution, in addition, hawthorn spider mite I maximum, the highest degree of aggregation.