Changes Of Aves Diversity Of The Muli River Valley And The Shuiluo River Valley In Sichuan

Aves is one of the most important biological group of the vertebrate. It plays an important role in nutrient cycling and energy flow in ecosystem.The Muli River and the Shuiluo River lies in the southeast of Qingzang highland and the middle of Hengduan mountain range. Unique landform and vegetations along the two rivers support high Aves diversity. From June to August of 1928, American naturalist Joseph F. Rock investigated fauna and flora in this region. 139 species of birds are recorded by Rock, which belong to 10 orders, 32families. We surveyed Aves of Muli river valley and Shuiluo river valley in 2004, the investigation range was similar to Rock's in northwest of Yunnan and southwest of Sichuan in 1928. 123 species of birds recorded, which belong to 11 orders, 31 families.The results of comparing our data with the data on avifauna collected by Rock in 1928 shows that 1) oriental realm species are dominant in both two surveys. 2) middle elevation area is the transitional zone of palaearctic realm species to oriental realm species, south and north avifauna mix obviously. 3) the percentage of oriental realm species increases with the elevation, and those oriental are mostly the birds of Himalay and Hengduan mountains distributional type, oriental species are dominant in high elevation. No changes of avifauna have occurred during the last 76 years.Obvious changes have been observed in diversity index, evenness index and species abundance index of Aves communities. These changes occurred in Aves...