1988—1989年安西极旱荒漠自然保护区进行了首次全面的综合考察,为了解1988年以来保护区鸟类资源的变化及其原因,2002—2004年又4次调查了该地区鸟类的种类及数量。15年来安西自然保护区的鸟类资源变化明显。鸟类种类新增加31种(其中甘肃新记录3种),但同时减少了36种。国家重点保护鸟类由原来的18种下降到16种。与1988—1989年相比,2002—2004年春季和夏季鸟类数量下降,秋季数量增加;各个季节的优势种的种类和数量都发生明显变化。影响安西自然保护区鸟类资源变化的主要原因是鸟类迁徙和人类活动。

The An'xi Extra-arid Desert National Nature Reserve,situated in the west of the Hexi Corridor in Gansu Province,is a nature reserve for desert eco-system.Bird species and their abundances in the reserve were surveyed during 1988-1989.In order to gain an understanding of the changes of bird resource at the reserve since 1988,line-transect method was used to investi-gate bird species,amount and environmental condition during 2002-2004.A total of 103 species of birds were recorded in the reserve during this period.In comparison with the record of 1988-1989,31 were new(among which three species were new records for Gansu Province),but 36 disappeared.The state protected birds in China decreased from 18 species in 1988-1989 to 16 species in 2002-2004.Six additional protected species of birds were recorded,but eight species were not re-counted in the second survey.Fifteen birds listed in Convention on International Trade in Endangered Species of Wild Flora and Fauna(CITES)were recorded during 1988-1989 and 2002-2004,but the species changed.There were eight species that were listed in China Red Data Book of Endangered Animals:Aves in 1988-1989,however,six were in 2002-2004.Aegypius monachus and Phoenicurus alaschanicus were listed in Threatened Birds of Asia in 1988-1989,and Otis tetrax and Falco naumanni in 2002-2004.Comparing bird abundance between 2002-2004 and 1988-1989,the amount of birds in spring and summer decreased,but those in autumn increased.Specially,species and amount of dominant species significantly changed in each season between 1988-1989 and 2002-2004.The main factors that led to the change of bird resources in An'xi Extra-arid Desert National Nature Reserve were bird migration and human activities.