Abstract: There is a snowmelt funnel around a  Populus euphratica trunk in Tugai forest. This paper analyzes the relationship between P. euphratica  crown and the shape of snowmelt funnel, and the difference of soil temperature, organic matter content and salt content in soil between the funnel area and the ground of forest gap. The results show that the salt content and organic matter content in soil under P. euphratica crown was higher than that of the ground of forest gap, which resulted in a higher soil temperature under the crown and the best capacity of insulation for forest when the frozen soil was melted in spring, because the soil under the crown could get more solar radiation and there was also a “fertile island effect”, thus a snowmelt funnel formed around a P. euphratica trunk. Water from snowmelt under the crown flowed to the roots of  P. euphratica in spring, which was advantageous for the growth of  P. euphratica forest. To some extent, snowmelt funnel can be used to explain the phenomenon of mutualism and associate among species. Taking the Tugai forest as an example, snowmelt funnels of  P. euphratica contribute to the survival of ephemeral plants in arid and semiarid areas.

Key words: snowmelt funnel, fertile island effect, Populus euphratica, Tugai forest, organic matter content, salt content, Ebinur Lake wetland