Background The oasis-desert transition zone is an ecologically sensitive and fragile zone in which deserts and oasis transform each other. How to choose sandy shrubs suitable for growing in this area is one of the hot topics for practitioner engaged in desert and oasis.

Methods In the desert-oasis ecotone in the southeastern edge of Tengger Desert, the surface soil sediment samples of 0-5 cm at the roots, 50 and 100 cm from the roots of Artemisia desertorum, Nitraria tangutorum, Haloxylon ammodendron and Hedysarum scoparium, along the northwest, southwest, northeast and southeast directions were collected. Statistical methods were used to analyze the grain size composition and parameter changes of sediments under the shrubs, and spatial interpolation method to analyze spatial changes.

Results 1) The composition of the surface soil sediments under the four shrubs was mainly medium sand; the grain-level content of the understory sediments was the same as that of A. desertorum and N. tangutorum, and the same for H. ammodendron and H. scoparium. 2) The average particle size of the sediment ranged from 1.39Φ-1.88Φ. The average particle size of the sediments under the N. tangutorum had no obvious change from the root to the periphery, and the particles were finer compared with the other three shrubs. The selectivity was medium, and the sediments of the other three shrub species were better. The skewness was negative and the kurtosis was medium peak. 3) Fine particles accumulated in the southwest direction under the A. desertorum forest, the northwest direction under the N. tangutorum forest, the southeast direction under the H. ammodendron forest, and the northeast direction under the H. scoparium forest. 4) Sediment grain size was significantly negatively correlated with plant height at 100 cm southwest of the four shrubs (P < 0.05), and positively correlated with coverage at 100 cm northwest (P < 0.05).

Conclusions N. tangutorum as the main sandy shrub in the transition zone, its sand-fixing and soil-holding ability is higher than that of other sandy shrubs. The growth of shrubs is concentrated and clustered, and the protection range is larger than other sandy shrubs.