Abstract:  To examine the effects of alien plants invasion on soil properties and soil carbon and nitrogen transition， the rhizosphere soil samples were collected under invasive plants， Ambrosia artemisiifolia L.， and the neighboring indigenous species， Torilis scabra Thunb. in a deserted paddy field. It was shown that contents of soil organic carbon， total nitrogen， nitrate and ammonium were increased by 89.13%， 42.15%， 43.69% and 35.36%， respectively， with the invasive plants， Ambrosia artemisiifolia compared to those with indigenous species. Similarly， soil microbial carbon and nitrogen biomass were increased by 52.08% and 61.26%， respectively， with the invasive plants. Under similar laboratory incubation conditions， soil mineralization and ammonification rates were increased by 141% and 206%， respectively， due to Ambrosia artemisiifolia invasion as compared to that of indigenous species. However， the effects of Ambrosia artemisiifolia invasion on soil nitrification and denitrification were not obvious. In conclusion， the present study revealed a significant shift in soil properties due to alien plants invasion. Soil carbon and nitrogen process was substantially facilitated， which may create a positive feedback as a consequence of alien plants invasion.

Key words: Ambrosia artemisiifolia L., invasive plants, carbon and nitrogen transition