Seasonal changes of photosynthesis rates and its effects on pri-mary production for Spartina

Some eco-physiological parameters for Sparti-na alterniflora and S. anglica in salt-marsh ecosystem in Bin-hai County of Jiangsu Province were observed and measured for a year. Rexults showed: maxium aboveground biomass was found in September,with 1714g (dry wt ) /m² and 419g (DW)/m² for S. alterniflora and S .anglica respectively Seasonal pat -terns of chlorophyll exhibited slope"Z" and flat "W" for S .al-terniflora and S .anglica respectively .The assimilation rates of photosynthesis for both species were higher in June than in september .Energy contents of plant material for two Spartina species varied from 12.56kJ/g to 20. 10kJ/g.