Abstract:

To evaluate carbon balance of Poyang lake wetland and quantify its carbon fixation function, aboveground and belowground plant biomass, as well as the net primary productivity（NPP）were measured by harvest method in a marshland dominated by 〖WTBX〗Carex cinerascens〖WTBZ〗 in the Poyang Lake Nanji Wetland National Nature Reserve from September 2009 to May 2011.Results indicated that both aboveground and belowground biomass showed clear seasonal variation pattern, ranging from 14608 to 1 77067 g/m2,and 1 80627 to 4 03256 g/m2,respectively.Ratio of belowground to aboveground biomass varied from 208 to 1744, with mean of 519. All the values of aboveground biomass,belowground biomass and NPP were higher in spring than those in autumn. Moreover, the flood time of marshland largely influenced the NPP of 〖WTBX〗Carex cinerascens〖WTBZ〗,NPP in year from 2010 to 2011 accounted for 625% of year from 2009 to 2010,and aboveground biomass decreased more markedly in contrast to belowground.〖WTBX〗Carex cinerascens〖WTBZ〗 in Poyang lake marshland has large carbon fixation capacity,with carbon fixation of 1 92383 and 1231.21 gC/m2 in the two year,respectively