Abstract: Roots are important vegetative organs of plants, and any slight environmental changes could cause changes in the root system. In this research, a space-for-time substitution method was used to select Artemisia ordosica on sand dunes with different activation levels, smaller in the horizontal direction, and more in the number of lateral roots. With the increase of the sand dune activation, the root distribution of A. ordosica is shallow, the number of lateral roots is reduced, but the horizontal distribution range is increased, and the root width is gradually expanded, there is a trend of evolution towards fibrous root plant. From fixed dune to heavily activated dune, due to the decrease of vegetation coverage and the intensification of wind-sand activities, the occurrence of sand-burial leads to the continuous increase of total underground biomass and root-shoot ratio of A. ordosica. The change of habitat led to the change of distribution pattern of roots of A. ordosica, which finally adapted to the soil moisture conditions and the corresponding ecological environment after the activation of dune.

Key words: biomass, roots distribution, root-shoot ratio