Abstract: The species and their abundance of arthropod communities in wheat fields of Qingzhou were in-vestigated at winter time during 1989-1992.It is found that the arthropod communities consist of 24 species,among which,16 species are beneficial for crops,8 species are harmful. The quan- itative dvnamics and characteristics of main pests and their natural enemies in the community are analysed using Shannon's index(H)and evenness(J').During winter time,the number of individuals in arthropod community is decreased, while the diversity, evenness and stability of the community are increased.

Key words: high temperature stress, Xinjiang hybrid hazel, photosynthesis, chlorophyll fluorescence.