干旱区研究2025，Vol.42Issue(3)：568-576,9.DOI:10.13866/j.azr.2025.03.16
洪积扇末端泥漠近地表风沙流结构特征
Structure of near-surface wind-blown sand over dry playa at the end of an alluvial fan
摘要
Abstract
The structure of near-surface wind-blown sand flow over dry playa represents the macroscopic charac-teristics of micro-wind-blown sand movement at such locations.It is important to study such sand flow in order to understand the processes of wind-blown sand movement and dust emissions in dry playa.In this study,a dry playa at the end of a typical alluvial fan around North Mountain of the Ejin Banner was selected for analysis and field observations were conducted on its near-surface wind-blown sand flow structure.The results revealed an ex-ponential wind speed profile over the dry playa surface and the aerodynamic roughness z0 was 0.058 mm,which is smaller than those of sand and gobi surfaces.The sand flux of mixed-particle-size sand decreased exponentially with height over the dry playa surface.The average saltation height zq of sand particles in the desert-crossing wind-sand flow was 15 cm,and 90%of the transport sand was concentrated within the height of 0-34 cm.The vertical profile curve of the sand flux in the fine-sand-particle-size group was similar to that of the mixed-particle-size sand.With increasing particle size,the sand flux in the dry playa changed with height,and the"elephant nose"curve transitioned to an"oblique Z"curve for coarse sand.Thus,this work proposes the mode of sand movement on the dry playa bed.关键词
泥漠/风沙流结构/风速廓线/跃移Key words
dry playa/wind-blown sand structure/wind velocity profile/saltation引用本文复制引用
江艳冰,周倩,王洪涛,谭立海..洪积扇末端泥漠近地表风沙流结构特征[J].干旱区研究,2025,42(3):568-576,9.基金项目
国家自然科学基金(42171015) （42171015）
第三次新疆综合科学考察项目(2021xjkk0305) （2021xjkk0305）
甘肃省自然科学基金(24JRRA088) （24JRRA088）
