在模拟的戈壁地表上,在人工极端降雨事件下,多个因素对粒子大小选择性的影响
Liying Sun1,2, Qingyuan Dai3,4, Ziheng Feng3,4
1Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China. sunliying@igsnrr.ac.cn.
Scientific reports
|December 28, 2023
概括
阿拉山戈壁沙漠的极端降雨显著影响粒子大小分布,影响潜在的亚洲尘埃来源. 柔和的斜坡和适度的石覆盖增强了微粒选择性,这对于尘埃排放预测至关重要.
科学领域:
- 环境科学 环境科学
- 地质形态学 地质形态学
- 大气科学 大气科学
背景情况:
- 了解影响颗粒大小选择性的因素对于估计亚洲尘埃排放源至关重要.
- 像阿拉山戈壁沙漠这样的干旱地区的极端降雨事件可以显著改变土壤特性和沉积物运输.
研究的目的:
- 调查降雨强度,斜坡梯度和砂覆盖在极端降雨事件期间对粒子大小选择性的影响.
- 分析土壤特性 (粘土,泥,微粒含量) 和与这些环境因素的丰富率之间的关系.
主要方法:
- 人工降雨模拟实验是在受控条件下进行的.
- 分析了粒子大小分布 (PSD).
- 使用回归模型验证了土壤特性与环境因素之间的关系.
主要成果:
- 降雨强度显著影响了流水和沉积物产量,而斜坡梯度是影响PSD的主要因素.
- 微粒选择性在降雨强度低 (20mmh-1),坡度温和 (3°),砂覆盖度适度 (30%) 的情况下最高,富化比 (ER<50) 为6.14.
- 粘土含量 (Clc) 和微粒含量 (Fic) 显示出与降雨强度和斜率的负指数关系,但与石覆盖的负指数关系. 含量 (Sic) 和ER<50与所有测试因素呈现负功率函数关系.
结论:
- 多种因素相互作用,影响颗粒大小选择性和潜在的亚洲尘埃排放源.
- 这些发现为在极端降雨情景下预测戈壁地区的尘埃排放提供了科学基础.
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