In order to reveal the photosynthetic characteristics of C.trichotomum responses to drought,salt and water-logging stresses,one-year-old potted seedlings were taken as materials,and the several stresses including natural drought,submergence stress,water-logging and different salt treatments(0.2%,0.4%,0.6%and 0.8%Na Cl)were carried out on August 15,2012.The morphological and photosynthetic characteristics were observed and determined.The results showed that adverse enviromental stress had a significant effect on the morphological changes and photosynthetic characteristics of C.trichotomum.On the 14th day after natural drought,the leaves wilted and could not recovery at night,and 60%of the seedlings could recover after re-watering.From the7th day to the 10th day after submergence stress treatment,the 2nd and the 3rd leaves at the base of 60%seedling turned yellow and the lenticels were observed.At the early stage of water-logging stress,white lenticels appeared at the base of seedlings,and the leaves wilted,chlorina and fallen off on the 8th day.A large number of leaves fallen off under 0.6%Na Cl or more salt stress,and even the whole plant died.The chlorophyll content,net photosynthetic rate(Pn)and transpiration rate(Tr)decreased gradually with the stress process,such as 8 days after natural drought,less than 0.4%salt stress and water-logging stress,but the changes were not significant compared with those of the control.With the increase of the stress intensity and the prolonged time,the changes of photosynthetic index were significant.All the results indicated that C.trichotomum had a certain degree of tolerance to drought,water and salt,but it was not suitable for living in water-logging condition for a long time. In order to reveal the photosynthetic characteristics of C.trichotomum responses to drought, salt and water-logging stresses, one-year-old potted seedlings were taken as materials, and the several stresses including natural drought, submergence stress, water-logging and different Salt treatments (0.2%, 0.4%, 0.6% and 0.8% NaCl) were carried out on August 15, 2012. The morphological and photosynthetic characteristics were observed and determined. The results showed that adverse enviromental stress had a significant effect on the morphological changes and photosynthetic characteristics of C.trichotomum. On the 14th day after natural drought, the leaves wilted and could not recover at night, and 60% of the seedlings could recover after re-watering. Fro the 7th day to the 10th day after submergence stress treatment, the 2nd and the 3rd leaves at the base of 60% seedling turned yellow and the lenticels were observed. At the early stage of water-logging stress, white lenticels were at the base of seedlings, a nd the leaves wilted, chlorina and fallen off on the 8th day. A large number of leaves fallen off under 0.6% NaCl or more salt stress, and even the whole plant died. chlorophyll content, net photosynthetic rate (Pn) and transpiration rate (Tr) decreased gradually with the stress process, such as 8 days after natural drought, less than 0.4% salt stress and water-logging stress, but the changes were not significant compared with those of the control. What the increase of the stress intensity and the prolonged time, the changes of photosynthetic index were significant. All the results indicated that C.trichotomum had a certain degree of tolerance to drought, water and salt, but it was not suitable for living in water-logging condition for a long time.