Abstract: As an important component for desert ecosystem, biological soil crusts(biocrusts) may possibly affect adjacent vascular plants via hydrology, soil erosion and nutrient cycling, while experimental evidences are still scarce and controversial. In the present research, we attempted to experimentally investigate whether and how biocrusts affect growth and nutrient uptake in vascular plants of the Gurbantunggut Desert. We conducted the experiments to examine the effects of biocrusts on growth and nutrient uptake in three widely distributed species of Erodium oxyrrhynchum, Alyssum linifolium and Hyalea pulchella. The results showed that the effects of biocrusts on the growth of three desert vascular plants were different in different growing phases. The biomass the three species in crusted soils were higher than those in uncrusted soils in the early growth period and lower in the later part of the growing period. While biocrusts did not significantly affect the biomass allocation between shoot and root. Biocrusts also influenced nutrient uptake by plants, especially promoting uptake of N and K, while did not affect the uptake of P. The influence on uptake of other elements(Cu, Ca, Mg, Na, Cl) was species-specific. We expect to provide important scientific basis on the potential vegetation succession direction in this desert ecosystem.

Key words: biological soil crusts, growth, nutrient uptake, desert herbs, the Gurbantunggut Desert