有机化梨园节肢动物群落时间动态的聚类分析

对北京顺义地区有机化梨园中2个不同栽培区节肢动物总群落、害虫及天敌亚群落分别进行时间动态的系统聚类。结果表明,在同一园区内,稀植区和密植区均以木虱为优势种类,相对丰盛度分别达0.3801、0.3300。总群落的24次调查结果稀植区可聚为5类,D=1.87,密植区聚为3类,D=1.80;害虫亚群落调查结果,当两区D=1.80时,稀植区可聚为3类,密植区可聚为4类;天敌亚群落调查结果稀植区聚为4类,D=2.12,密植区聚为5类,D=1.75。在早春的密植区和入秋的稀植区木虱发生量大,应加强监测,及时防治。

Cluster analysis on the temporal dynamics of arthropod community in organic pear orchards

By the method of fuzzy clustering, the temporal dynamics of the arthropod community and sub-communities in two different management areas in organic pear orchards were studied in Shunyi, Beijing. The results showed that Psyllidaes were the predominant insects in sparsely- and densely-planted areas, and their relative abundances were 0,3801 and 0. 3300, respectively. The total community could be grouped into 5 clusters （D = 1.87） in planted areas and 3 clusters （D = 1.80） in densely-planted areas. The pest sub-communities could be grouped into 3 clusters （D = 1,80） in sparsely-planted areas and 4 clusters （D = l. 80） in densely-planted areas. The natural enemy sub- communities could be grouped into 4 clusters （ D = 2.12） in sparsely-planted areas and 5 clusters （ D = 1.75） in densely-planted areas. The number of Psyllidaes was very large in the densely-planted areas in early spring and in sparsely-planted areas in autumn. It is therefore suggested that investigation during these periods be intensified and prevention implemented.