Targeted control of sand hazards for a railway in extremely arid regions using fingerprinting approaches

Abstract Reliable quantitative information on sediment sources is key for the reasonable arrangement of targeted measures that effectively control hazards of wind erosion along railways in extremely arid regions. In Northwest China, the newly built Golmud-Korla Railway suffers from serious wind-blown sand hazards, which severely affect its future safe operation. This study applied two frequently used fingerprinting methods (optimum composite fingerprint and multiple composite fingerprint) to quantitatively examine the contributions of different sediment sources to the railway in two typical areas (research areas: R1 and R2). The results revealed that Nebkha was the main sediment source for the railway (46.5%) in R1, followed by a dry playa (37.7%) and sand dunes (Dune 1) (15.8%). In contrast, sand dunes (Dune 2) were the main sediment source for the railway (75.2%) in R2, followed by gobi (12.9%) and a low-lying coarse sand sheet (LCSS) (11.9%). According to the comprehensive assessment, the sand-fixing measure of spraying salt lake brine to form a crust for Nebkha was recommended, and the sand-fixing measure of large vertical grids (15 m × 15 m × 1.5 m) made of reed rod was suggested to control wind erosion of the dry playa near the railway and to trap the eroded sand from the upwind direction in R1. In R2, a small reed rod checkerboard barrier (1 m × 1 m × 0.2 m) was suggested for Dune 2 to effectively prohibit drifting sand from endangering the railway. In addition, this study also indicated that when two or more sediment sources have relatively similar properties, the pairwise test to select tracers with significant differences between the two sediment sources would help reduce uncertainty, which was recommended for similar studies in the future.