Abstract: The water consumption for the agricultural production and the natural vegetation can not be ensured downstream from Daxihaizi Reservoir at the lower reaches of Tarim River owing to the reduction of the feeding water, and the accumulated time of stream cut-off here has been as long as 10～20 years. Because of shortage of water, the desertification is sped up, wind erosion becomes violent, the ecological environment is degenerated, and the desert forests along the banks of Tarim River downstream from Daxihaizi Reservoir will disappear if the situation is not changed. Therefore, a stream water volume of 2.0×10⁸m³ was fed to the stream cut-off river section at the lower reaches of Tarim River in an emergency during the period from mid-May to mid-July. Later 5 sections are investigated, which include the regenerating and growing situation of the plants, biomass of the grasses, distribution and quantity of the roots, distribution characteristics of the natural vegetation, soil status, distribution of groundwater, etc., along the river banks. The results show that the effects of the emergency stream water feeding to the stream cut-off river section to the regeneration of the natural vegetation along the river banks are obvious, especially to the grasses, then to the shrubs and trees.

Key words: emergency stream water feeding, vegetation regeneration, biomass, ecological benefit, Tarim River