Dome dunes are transient forms and represent an intermediate stage of barchan dune evolution, which are influenced by the interactions between surface conditions and wind regime. 

However, we know little about dome dunes except for fragmentary reports of their morphometric features and movement. 

Recently, a research group from Northwest Institute of Eco-Environment and Resources (NIEER) of the Chinese Academy of Sciences measured the morphological parameters of 60 dome dunes by means of real-time kinematic GPS in the northeastern Qaidam Basin. 

By examing the characteristics of the dune sediments, the internal sedimentary structures and regional wind regimes, scientists found that local alluvial and fluvial sediments appear to provide the necessary materials for the dome dunes, and that the dunes evolved from sand patches under a variable, gentle winter wind. 

The variations of the wind regime and sediment supply during the movement of these dunes made their destiny uncertain, although research analysis suggested that more than 60% of them will be dispersed by the wind, and only 20% may evolve into barchans. 

Some dune morphological characteristics, such as the windward and leeward slopes, the height, and the lengths of the main axes could be used as signs of the degree of dune evolution, and the linear relationships among these variables provided a possible way to estimate 3D parameters of these dunes (such as their volume) from 2D satellite images. 

Besides, according to the study results and the Andreotti saturation length theory, scientists also estimated the lengths at which the dome dunes disperse or begin to evolve into barchan dunes. 

This results revealed the wind regimes responsible for formation and evolution of the dome dunes and supported a discussion of their initiation and evolutionary processes, which enhanced our understanding of dome dune morphodynamic processes and improved numerical simulations of dune evolution. 

The study result was published In Geomorphology. 

Contact: 

QIAN Guangqiang 

gqqian@lzb.ac.cn