Abstract: This paper studied the seasonal dynamics of phosphorus and biomass accumulation of two types Calamagrostis angustifolia in Sanjiang Plain wetland, aimed to explore the relationship between phosphorous uptake by the plants and their biomass accumulation, and to understand the characteristics of phosphorus accumulation and transference in wetland ecosystem. The results showed that for the two types of C. angustifolia, there was a distinct seasonal variation of aboveground and underground biomass and phosphorus accumulation, but the extent was differed with plant type, which should be related to the habitat condition and the physiological adaptability of the plants. Phosphorus was very important for the early growth of C. angustifolia, while habitat was not the main factor affecting phosphorus accumulation.

Key words: Paddy field, Soil-water system, P application, P loss (potential), Environmental impact