This paper studied seasonal and spatial changes of biomass above-ground and under parts in the Calamagrostis pseudophragmites community. The results showed obviously season al dynamics in biomass at the Caldmagrostis pseudophragmites community. Aboveground biomass achieved maximum value (142. 54 g/m2 ) in mid-September. Underground biomass was mainly concentrated on 0-10 cm of the soil layer, seasonal changes was significant too,and lowest value (170. 32 g/m2) appeared in May, the maximum appeared in Septe...