Morphometric characteristics and sand intercepting capacity of dominant perennial plants in the Eastern Qaidam Basin: Implication for aeolian erosion control

Abstract

The Qaidam Basin is a region with strong sandstorm activity in China, and nabkhas play a very important role in aeolian erosion control and maintaining stability of the ecological environment in this region. This study examined the effects of dominant perennial plants on nabkha formation. Five species (the shrub of Ephedra przewalskii and Calligonum zaidamense, the subshrub of Krascheninnikovia ceratoides and Sympegma regelii, the perennial herb of Artemisia desertorum) were selected. Length (Ln), width (Wn) and height (Hn) of nabkhas were used to represent nabkhas shape, the nabkha volume (Vn) was approximately estimated to represent sand intercepting capacity. Among the morphometric parameters of nabkhas and plants, Ln, Wn, Hn, Sn and Vn of the nabkhas showed less correlation with plant height (Hp), especially C. zaidamense, K. ceratoides and A. desertorum (r < 0.45). Ln, Wn, Hn, Sn and Vn of the nabkhas were significantly related to length (Lp), width (Wp), canopy area (Sp) and upwind profile (Sup) of the plant, especially E. przewalskii, C. zaidamense and S. regelii (r > 0.612). The sand intercepting capacity of the five plants was as follows: E. przewalskii > C. zaidamense > S. regelii > A. desertorum > K. ceratoides. The results indicate that E. przewalskii has large sand intercepting capacity. Moreover, the sand accumulation of C. zaidamense is greatly affected by the plant canopy in the early growth stage of the plant. Dwarf and highly branched semi-shrub S. regelii is beneficial to intercepting sand in unit canopy area and has big sand intercepting potential. A shelterbelt system combining fast-growing shrubs (C. zaidamense), shrubs (E. przewalskii) and semi-shrubs (S. regelii) in the windward direction is recommended for controlling aeolian erosion and improving the ecological environment in arid areas.