Study on the relationship between CO2 absorption and aboveground biomass of riparian wetland plant communities in inland river, Inner Mongolia plateau

In this study, we measured CO₂ absorption and biomass of the typical wetland plant communities using the LI-7000 CO₂/H₂O analyzer in the Xilin River Basin, Inner Mongolia, China. The results are as follows: 1) The Poa annua+Equisetum arevene Community, Lathyrus palustris Community, Polygonum alopecuroides Community, Cirsium esculentum Community, and Glyceria maxima+Equisetum hyemale Communitiy have a similar changing trend of photosynthesis, taking photosynthesis ability in early July as strongest, while flooded community which is composed of Glyceria maxima and Equisetum hyemale achieves the peak of photosynthesis ability in late July. 2) During the growing season, the biomass of community dominated by Polygonum alopecuroides reached the extreme value at the beginning of September, whereas the biomass of other communities presented the extreme value in mid-August. 3) For a wetland plant community, there is not a remarkable relevance between CO₂ fixed and aboveground biomass, and it can not use the CO₂ fixed by community to reflect the standing crop of community.