[Community succession patterns of pests and natural enemies in jujube orchard ecosystem].

Through investigation and by the methods of optimal partitioning, principal component analysis, and one-or two-dimensional ordination, this paper analyzed the main groups and succession trends of the pest and natural enemy communities at a jujube orchard of Taigu area. The results showed that the communities had more obvious dominant factors and temporal succession pattern. The first three principal components of the communities had a bigger variation, with an obvious follow effects. The community succession was temporally divided into four stages, i. e., in the periods of pre-budding, leaf expanding and blooming, fruiting, and maturing. The dominant species of pests and their natural enemies were demonstrated.