Parametrization of the increase of the aeolian erosion threshold wind friction velocity due to soil moisture for arid and semi-arid areas
Parametrization of the increase of the aeolian erosion threshold wind friction velocity due to soil moisture for arid and semi-arid areas
复制标题
DOI：
10.1007/s00585-999-0149-7
复制
发表时间：
1999-01
影响因子：
1.9
通讯作者：
F. Fécan;B. Marticorena;G. Bergametti
中科院分区：
文献类型：
--
作者：
F. Fécan;B. Marticorena;G. Bergametti
半干旱地区土壤扬尘的大尺度模拟需要考虑土壤水分对土壤风蚀阈值的影响。土壤水分的保持是由土壤颗粒表面的分子吸附和颗粒间的毛细作用力共同作用的结果。颗粒间毛细力（以水分张力为特征）是导致土壤水分增加时风蚀阈值增加的主要因素。当土壤含水量接近但小于最大吸附水量w′（取决于土壤质地）时，这些毛细力被认为不足以显著增加侵蚀阈值。由保持曲线导出了水分张力与土壤含水量和w′的关系式。从这个表达式中，参数化的比例的湿，干侵蚀阈值已被开发为土壤水分和土壤质地的函数。这个参数化的系数已被确定通过使用文献中的实验数据。建立了w ′与土壤粘粒含量的经验关系。不同土壤质地的侵蚀阈值比模拟结果与试验结果吻合较好。
Large-scale simulation of the soil-derived dust emission in semi-arid regions needs to account for the influence of the soil moisture on the wind erosion threshold. Soil water retention consists of molecular adsorption on the soil grain surface and capillary forces between the grain. Interparticle capillary forces (characterized by the moisture tension) are the main factor responsible for the increase of the wind erosion threshold observed when the soil moisture increases. When the soil moisture content is close to but smaller than the maximum amount of adsorbed water,w′ (depending on the soil texture), these capillary forces are considered as not strong enough to significantly increase the erosion threshold. An expression of the moisture tension as a function of soil moisture and w′ is derived from retention curves. From this expression, a parametrization of the ratio of the wet to dry erosion thresholds has been developed as a function of soil moisture and soil texture. The coefficients of this parametrization have been determined by using experimental data from the literature. An empirical relationship betweenw′ and soil clay content has been established. The erosion threshold ratios simulated for different soil textures were found to be in good agreement with the experimental data.