Abstract: Pot experiment showed that after 30 days of transgenic Bt rice planting and by the end of the growth season of transgenic Bt cotton,the contents of soil total C,total N,alkalihydrolyzable N,and available P and S had no significant difference with the control,which suggested that there was a little disturbance in the cycle and balance of soil nutrients after a short period of transgenic Bt crops planting.

Key words: Gap model, Forest succession, Plot area