| The research was carried out in the wetland estuary of the Minjiang River since May, 2007 to February,2008.The biomass of the major plant communities,carbon content of different plant communities and soil were determined to study the carbon storage of Minjiang River ecosystem.The main plant communities of wetland estuary of Minjiang River have been studied on carbon storage,and carbon balance to provide data on the carbon cycle.Major conclusions were summarized as follows:1.The seasonal dynamics rule of the main plant communities biomass in Minjiang River estuary:After turning green in late April,the plants carried on the vegetative growth in May,the biomass was less.Along with the birth time's advancement,entered the growth and the reproduction vegetal period,the biomass increased gradually.After some time,due to the adult plant is then senile,and the losing plant amount of space occupied incr- eases, the biomass started to drop.The plant body aboveground and underground biom- ass's maximum value appeared in August.In the Eel-beach,the Spartina alterniflora community,Phragmites australis community,C.malaccensis Lam.var.bervifolius Bocklr. Community total biomass maximum value was 40.96 t·hm-2,41.30 t·hm-2,and 31.17 t·hm-2 respectively.Among the main plant community's average biomass,the Spartina alterniflora community(34.04 t·hm-2)＞the Phragmites australis community(27.21 t·hm-2)＞the C.malaccensis Lam.var.bervifolius Bocklr.Community(20.21 t·hm-2).Opening up the wetland artificially,changing the wetland soil type which affected the wet degree and the plant body's growth.The wetland plant community's biomass also was different.In a growth cycle,aboveground biomass of Phragmites australis community(Eel-baech) was13.18 t·hm-2～26.18 t·hm-2,while the bat-continent's was 12.61 t·hm-2～20.94 t·hm-2.2.In the Eel-beach,plant carbon content aboveground of Spartina alterniflora community and Phragmites australis community were varied by seasonal:May＞August＞November.While its change rule of C.malaccensis Lam.var.bervifolius Bocklr. community was not obvious.The average plant carbon content aboveground of Spartina alterniflora community,Phragmites australis community,C.malaccensis Lam.var. bervifolius Bocklr.Community was 34.57%,38.27%,37.08%,respectively.The rule of plant carbon content underground of Eel-beach was as follow:May＜August＜November. The average plant carbon content underground of Spartina alterniflora community, Phragmites australis community,C.malaccensis Lam.var.bervifolius Bocklr.Community was 36.62%,36.28%,30.89%,respectively.3.The change tendency of carbon content by various soil profile was not the same, the regularity was not obvious.The natural wetland carbon accumulation was the climate and the environmental condition synthesis reflected that disturbed the activity with the fierce climate and the environmental variation as well as the humanity and so on many factors to be closely related.Artificial opened up wetland,changed the wetland alternation of wetting and dry environment,have had the influence to the soil carbon content.Compared with the Eel-beach,soil carbon content of Phragmites australis community in the bat-continent was smaller.In the bat-continent,at the depth of 0-20cm,20-40 cm,40cm-60cm,soil carbon content of Phragmites australis community was 1.62%～1.64%,1.56%～1.61%,1.53%～1.60%respectively.Various layers soil carbon content in Phragmites australis community of the Eel-beach were 1.65%-2.22%, 1.69%-2.03%and 1.53%-2.24%in turn.4.Vertical increases along with the depth of soil,the carbon storage in the Eel-beach increased gradually.In the Eel-beach,sediment profiles of the Spartina alterniflora community,the average carbon storage were 23.27 t·hm-2,26.21 t·hm-2,28.65 t·hm-2. Sediment profiles of the Phragmites australis community,the average carbon storage were 30.30 t·hm-2,30.66 t·hm-2,32.41 t·hm-2.Sediment profiles of the C.malaccensis Lam.var. bervifolius Bocklr.Community,the average carbon storage were 24.67 t·hm-2,26.77 t·hm-2, 29.02 t·hm-2.Along with the season change,the soil carbon storage in the Minjiang river astuary was increases gradually.In May,in August,in November,the soil carbon storage in Phragmites australis community of the Eel-beach was77.87 t·hm-2,92.64 t·hm-2,106.80 t·hm-2,respectively.5.Soil carbon storage in both exposed sand beach and tidelands was smaller than that in the wetland which plant covered.At the depth of 0-60cm,the Eel-beach exposed sandbar's soil carbon storage was 62.06 t·hm-2.At the depth of 0-60cm,the Eel-beach exposed shallow seas and tidelands's soil carbon storage was 72.21 t·hm-2.The soil carbon storage in Spartina alterniflora community of the Eel-beach was78.13 t·hm-2.The carbon storage in wetland soil was an important component in the wetland ecosystem.The soil carbon storage in the Spartina alterniflora community,the Phragmites australis community and C.malaccensis Lam.var.bervifolius Bocklr.Community of the Eel-beach, were account for 86.61%,90.32%,92.23%respectively among the ecosystem carbon storage.
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