Abstract: In general residential area, there is only one species of fly(Musca aomestica). But m residences located in agricultual free market, 7 species are found, dominated by M. domestica(80.90%)and Lucilia sericata(10.11%).In small restaurant, 5 species are recorded, with the percentage of 98.81% Musca domestica and 0.51% Lucilia sericata. In agricultural free market, 27 species are traped, numerical sequence of which is:39.34% L. sericata, 12.96% Aldrichina grahami, 11.13% Musca stabulans, 8.66% Chrysomya megacephala, 0.07—5.28% others. The seasonal appearence of common flies is: Musca domestica in Jan.—Dec., M. Stabulans in May—Sept.,Aldrichiua grahami in Jan.—Sept., Lucilia sericata in April—Nov., Hemipyrellia liqurriens in May—Nov.and Chrysomya megacephala in July—Nov..

Key words: Sphagnum, shading, light competition, positive interaction, stress gradient hypothesis