Abstract: In this paper, the single inflorescence length, flower number, bearing rate and fruit quantity, and the seed germination rate of Tamarix hispida under different groundwater levels at the riverside in the lower reaches of Tarim River were investigated after the water transportation having been stopped for 30 years, with the normal water condition as the reference. The results showed that all the parameters except single inflorescence bearing rate and seed germination rate had significant differences among the observation points. After 7 years urgent water transportation, the single inflorescence length and flower number were assured at the point 300 m away from the river when the groundwater level was about 5.5 m, and the single inflorescence fruit quantity was assured at the point 500 m away from the river when the groundwater level was about 6 m. The single inflorescence bearing rate and seed germination rate were still relatively high at the point 1 000 m away from the river when the groundwater level was less than 7.5 m. Drought condition first restricted the single inflorescence length and flower number, and then, restricted the single inflorescence fruit quantity. Under water deficit, certain rates of inflorescence bearing and seed germination could be still maintained so as to insure the existence of T. hispida population.

Key words: Polygonum cuspidatum, Resveratrol, Mineral elements, Meteorological factors, Principal component analysis