Abstract: Species richness and composition of breeding birds in Guangxi Province were evaluated based on the publications and field records (updated to 2015). A total of 428 breeding species were recorded in Guangxi Province, which belong to 20 orders and 67 families. 81.07% of them are residents (347 species). Aquila chrysaetos, Tragopan caboti, Syrmaticus ellioti and S. humiae are listed as grade I national protected species in China. Sixtyeight species are listed as grade Ⅱ national protected species. Twenty species are listed in the IUCN Red List, including 2 Endangered, 8 Vulnerable and 10 Near Threatened. More species were found in Oriental realm (77.34%) than in Palearctic realm (7.24%) and in both realms (15.42%). 89.02% species, mostly Oriental species (72.43%), prefer woodland, whereas species in Palearctic realm and both realms are generalists. A high number of species were found in southwestern Guangxi and coastal area of southern Guangxi, and accounted for 82.24% and 61.21% of all breeding species in the province, respectively. Thus, these areas, particularly woodland habitats, should be considered with conservation priority.

Key words: net anthropogenic nitrogen input (NANI), Huaihe River Basin, nitrogen pollution, nitrogen budget.