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Cunnininghammier lanceolata and Pinus taeda were introduced to Kunyu Mountain in the early 1950s and 1970s,respectively.After a long period of adaptation,these two species have survived at elevations < 500 m on Kunyu Mountain.To understand the species adaptations to this new habitat,the population and community characteristics of the habitats where these two species have successfully established were investigated.The results showed that:(1) C.lanceolata grows well and produces seeds and seedlings and has formed a mixed-age stand indicating that C.lanceolata has natural regeneration ability.Pinus taeda grows well too but had fewer seeds and seedling; (2) The soil seed bank in the C.lanceolata community was 398.5 seeds/m2,including 3.35 seeds/m2 of C.lanceolata seeds,while there were only 10.4 seeds/m2 in the P.taeda community with no P.taeda seeds; (3) The species richness and species diversity index showed that the tree layer > herb layer > shrub layer in C.lanceolata community,whereas species richness in the P.taeda community decerased from the herb layer > shrub layer > tree layer.It is inevitable that the P.taeda population will decline because natural regeneration in Kunyu Mountain is limited.In addition,there is lower tree diversity and stability in the P.taeda community.We suggest that local evergreen conifer trees such as P.thunbergii and P.densiflora be introduced into the P.taeda community in order to stabilize community structure that favors water-soil conservation of the mountain area.