Abstract: One year's study on the decomposition and nutrient dynamics of leaf litter in pure and mixed stands of poplar and black locust shows that the decomposition of poplar leaf litter was slow, and that of black locust leaf litter was fast; the mixed stand had a faster decomposition speed of leaf litter than poplar.During decomposition the Nand Prelease of poplar leaf litter was difficult, taking more than 10 months for nutrient immobilization; while than of black locust leaf litter was much easier.The time and range of Nand Pimmobilization of leaf litter in mixed stand were cut down, and the decomposition speed of leaf litter increased, indicating that mixed planting with poplar and black locust was beneficial to the decomposition of leaf litter and the cycling of Nand P.

Key words: Poplar, Black locust, Mixed stands, Leaf litter, Decomposition