Three-dimensional spatial pattern of Populus euphratica nebkhas in the sparsely forested sandy land on the west of the Hotan River

A Populus euphratica nebkha is a type of wind-accumulated landform. In arid desert areas, when the wind-sand flow is blocked by P. euphratica, sand materials accumulate under and around trees. West of the Hotan River, P. euphratica is widely distributed in the sparsely forested sandy land to the south of Mazartag Mountain. The P. euphratica nebkha geomorphology is formed by wind erosion of sand and has rarely been studied. Based on a field investigation using real-time kinematics (RTK), the three-dimensional morphological characteristics and spatial distribution of the Populus euphratica nebkhas at 10 plots west of the Hotan River were quantitatively analyzed based on GIS data and statistical methods. The results were as follows. 1) The nebkhas exhibited an irregular contour with significant spatial differences in morphological parameters. Most nebkhas were in the developmental stage. 2) All nebkhas exhibited a patchy distribution, and at the patch level, P. euphratica nebkhas were dispersed throughout the study area and distributed on slopes ranging from 20° to 40°. 3) P. euphratica nebkhas were mainly distributed in the southwestern portions of the study area and on both sides of the old watercourse.