第六届青年地学论坛

1235 / 2019-08-07 14:55:04

Assessing Aeolian Sediment Provenance in the Cuona Lake Section along the Qinghai-Tibetan Railway

10、干旱区环境与风沙科学 > 专题3：风沙（风蚀）动力学与数理模型

Abstract: The Cuona Lake Section of the Qinghai-Tibetan Railway is under constant threat from aeolian sand deposition due to wind erosion. However, the provenance of this aeolian sediment remains unclear. Therefore, annual wind data and soil particle-size distributions were used to authenticate the fingerprinting results of various statistical procedures. This integrated information was used for reliable assessment of the contributions of each source. The results showed that (1) wind erosion behaviours that contribute to sand sediment occur mainly on the west side of sandy areas during October to April. The resultant drift potential of this period reached 1086.18 VU, indicating a high energy level. (2) Degraded alpine meadow had the highest volume-based fractal dimension and greatest proportion of the fine fraction, showing that the wind erosion intensity of this source type is lowest. (3) Estimation using the permutation algorithm showed the lowest uncertainty and good agreement with qualitative results. The contributions of the source areas were estimated as 0.04 for degraded alpine meadow, 0.55 for bare hilly land, and 0.41 for river courses. The provenance of aeolian sediments was characterised through a combination of fingerprinting and classical aeolian research techniques in this study. These results will provide a firm basis for desertification control in the Cuona Lake section and can be used as references for other areas experiencing threats from aeolian sand.