Abstract: Artemisia intramongolica is an important semi-shrub in the Hunshandake Sandy land and it has degraded significantly in the desert succession series from shifting to fixed sandy land.In order to find out the vital reasons of its degradation,the bioecological features and its habitat characteristics of A.intramongolica were studied in shifting,semi-shifting,semi-fixed and fixed sandy lands.The results showed that there was no significant difference in soil moisture among the different plots and the layers of soil before raining period.With the sandy land fixation,the soil moisture in 0～5 cm surface layer increased gradually.After raining period,though the soil moisture among plots had no significant difference,the maximum of soil moisture all occured in 0～5 cm surface layer.The contents of soil organic material and total nitrogen in plots were significantly different,which showed increase trend with the sandy land fixing.Though there was no significant difference among ramets and modules,the characteristics which reflected the ecological functions of population,such as canopy extension,biomass and reproductive allocation,were significantly different in plots and showed decline trend with the sandy land fixing.On this condition,the compositive vigour index (CVI) for A.intramongolica population was put forward to analyze the correlation between its characteristics and soil factors.It showed that with the sandy land fixing,there were significant difference between CVI of different succession stages.Its value decreased from 0.63 of shifting sandy land to 0.38 of the fixed,which negatively correlated with the contents of soil organic material and total nitrogen.

Key words: Cutting, Forage grass, Eco-physiological characteristics, Root system, Biomass