Abstract: From September 2003 to November 2005, an investigation on the seed ingestion and dispersal of Phoebe hunanensis by birds was conducted in the Spirit Valley forest at the southern foot of Zhongshan Mountain of Nanjing, Jiangsu Province, East China. Five resident bird species Turdus merula, Garrulax perspicillatus, G. pectoralis, Urocissa erythrorhyncha, and Cyanopica cyana were observed to frequently ingest the fleshy drupes in P. hunanensis crown, and to help the seed dispersal by rejecting the drupes stone after ingestion. The germination of P. hunanensis seeds was not affected after the ingestion by birds, but the seedlings emergence rate of the rejected seeds was higher. The birds could disperse the seeds wider to the habitats favorable to the seed germination, seedling survival, and population establishment of P. hunanensis. Possibly due to the seed dispersal of P.hunanensis by birds, twenty seven mother trees initially introduced and cultivated at the edges of the Spirit Valley forest in 1961 had multiplied into thousands of saplings and young trees, which were successfully settled in the areas within a distance of about 300 m around the mother trees. As a result, the species composition of evergreen trees in the Spirit Valley forest became richer, and the succession and development of forest community in study area was promoted.

Key words: Soybean, O₃, CO₂, Interaction