Background

Sand burial and precipitation drive the community structure and function of semi-arid grassland. Stipa bungeana is a tillerous clonal plant that often forms a community in the sandy grassland, however, it is not clear how sand burial, precipitation enhancement and their interaction on importance of S. bungeana in the plant community. In the semi-arid desertification grassland in northern China, we conducted a two-years field experiment with simulated sand burial (no sand burial, 2 cm and 5 cm sand burial) and precipitation enhancement (ambient precipitation, 1/7 and 2/7 precipitation enhancement) treatments, and the morphological characteristics and important value of S. bungeana were determined.

Results

Sand burial and precipitation enhancement promoted the growth of S. bungeana tillers, but reduced the size and aboveground biomass of S. bungeana tuft, thus affecting the status of S. bungeana in the community. Sand burial and precipitation enhancement also significantly reduced plant density and aboveground biomass of all other species except S. bungeana.

Conclusions

These results revealed that S. bungeana may lose its status as the constructive species, due to the accumulation of the negative effects of sand burial. Our findings may be helpful to better understand the process of desertification, and will contribute to grassland management and vegetation restoration in semi-arid desert areas.