A Study on Community Characteristics of Geometridae and Insect Faunal in Baishuijiang Nature Reserve of Gansu Province

1950 specimens of Geometridae collected in the Baishuijiang nature reserve,Gansu province.187 species of Sphingids (including 3 unnamed species and 48 species newly recorded in Gansu) belonged to 110 genera of 5 subfamilies.Ennominae was the dominant group which had a total of 114 species belonging to 65 genera.The dominance of the genus was 59.09% and that of the species was 60.96%.Larentiinae was the subdominant group,which had a total of 42 species belonging to 25 genera.The dominance of the genus was 22.73% and that of the species was 22.70%.Sterrhinae had 7 species in 3 genera and Geometrinal had 21 species in 15 genera;their dominances of the species were 3.78% and 11.35% respectively.Larentiinae was a rare group,which had 3 speices belonging to 2 genera;Thair diminances of the genus and the species were 1.82% and 1.60% respectively.The results showed that species were diversified and their community structure was complicated.An analysis of insect fauna materials showed that 52 species appertained to the Oriental Realm,making up 27.81% of our collection; 12 species belonged to the Palaearctic Realm,making up 6.42% of the total,and other 123 made up species about 65.78% of the total were scattering widely in the above two realms.The results showed that the Baishuijiang nature reserve was a transitional area from Oriental to Palaearctic Realm.