Abstract: This study examined the effects of temperature, seed size, and substrate type on the germination of Nitraria sphaerocarpa. The results showed that either on filter paper or on sand substrate, the germination percentage, mean germination time, and germination rate index of N. sphaerocarpa were significantly affected by temperature, but not by seed size. On sand substrate, the germination percentage was higher at constant temperature of 25 ℃-35 ℃ and alternating temperature of 20 ℃/30 ℃, but lower at 10 ℃. The mean germination time was decreased with increasing temperature. On filter paper and sand substrate, the base temperature, optimum temperature, and maximum temperature of germination were 9.0 ℃, 25.3 ℃ and 45.2 ℃, and 4.8 ℃, 34.1 ℃ and 45.0 ℃, respectively. This extended temperature range forN. sphaerocarpa germination and the ability of N. sphaerocarpa to germinate rapidly suggested the high potential of N. sphaerocarpa to establish on sandy land.

Key words: Eutrophication, Phytoremediation, Sediment, Aquatic plant