Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Accueil du site → Master → Canada → Effects of a natural windbreak on dust dispersion in the neutral surface layer

University of Alberta (2013)

Effects of a natural windbreak on dust dispersion in the neutral surface layer

Mao, Yiwen

Titre : Effects of a natural windbreak on dust dispersion in the neutral surface layer

Auteur : Mao, Yiwen

Université de soutenance : University of Alberta (Canada)

Grade : Master of Science (MS) 2013

Résumé
Field experiments were conducted in Indian Head, Saskatchewan in order to study the effects of a natural shelterbelt (width-to-height ratio W/H = 0.5) on dust dispersion from a gravel road. Transects of dust concentration sensors running normal to the road were placed both in the lee of the windbreak and in an adjacent unsheltered region. A Lagrangian stochastic (LS) model was developed to compute the theoretical ratio (c/Q) of concentration to emission rate and infer time average concentration (c) and the ensemble mean concentration transient. In about 69% of cases the inferred time average concentration lay within a factor of two of the corresponding observations (FAC2 = 69%). The modeled and experimental results suggest that the natural windbreak is not effective in filtering small dust particles (D ≤ 20 μm), but that windbreak entrapment can be a significant mechanism to remove large dust particles (D ≥ 50 μm).

Présentation

Version intégrale

Page publiée le 16 novembre 2013, mise à jour le 2 février 2018