Abstract:We describe effects of two substrate types, two storage ways and three salinity levels on germination characteristics of three dominant coastal plants, Spartina alterniflora, Suaeda salsa and Phragmites australis, with the goal to explore their strategies of seed germination in coastal environments. Increased salinity significantly lowered germination of all species after dry storage and that of P. australis after moist storage, whereas S. alterniflora and S. salsa after moist storage showed no significant difference. Seeds of S. alterniflora in all salinity treatments and S. salsa in median and high salinity treatments after dry storage and P. australis failed to germinate in the soil substrate. In water condition, only seeds of P. australis with dry storage in median and high salinity treatments and moist storage in high salinity failed to germinate. Moist storage had positive effects on total germination and germination rate of S. alterniflora in all salinity treatments and S. salsa in median and high salinity treatments in soil substrate, as well as those of S. salsa in median and high salinity treatments and P. australis in freshwater and median salinity treatments in water condition. Seed germination of S. alterniflora after dry storage was inhibited by median and high salinity, as well as soil burial, restricting its expansion towards high marsh. But moist seeds inundated by seawater frequently could better withstand high salinity and soil burial, leading to S. alterniflora to populate in the lower marsh. P. australis after moist storage obtained highest total germination and germination rate in freshwater, which was thought to give P. australis a competitive advantage in salt marsh conditions that received freshwater input; nevertheless, spreading toward sea of P. australis was inhibited by salinity and soil burial. Seeds of S. salsa obtained highest germination rate in both saline and buried conditions, showing rapid germination strategy and widely adaptation, which was responsible for occupying the middle and high marsh in the coastal environments.