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

Titre : Effect of vegetation cover and transitions on regional wind erosion in drylands

Auteur : Youssef, F.

Université de soutenance : Wageningen University

Grade : Doctor of Philosophy (PhD) 2012

Résumé partiel
Wind erosion is a critical environmental problem that threatens mainly the arid and semi-arid regions of our planet. Usually this problem is associated with desertification, poverty and other environmental and socioeconomic problems. Wind erosion causes the loss of fertile topsoil, and has a negative effect on agricultural production and on human health. When conditions favorable for wind erosion are present, the process can cause large scale environmental disasters like the Dust Bowl in the USA in the 1930s. This event is considered one of the worst environmental disasters of the 20th century, and was caused by a reduction in vegetation cover due to a change in land use combined with an increased dryness in the region. Wind erosion involves the detachment, transport and deposition of soil particles. Depending on their size, particles can move in three different types of transport : creep, saltation and suspension. Vegetation is one of the key factors in the protection of the soil against erosive winds. Although research on wind erosion has started a few decades ago there is still a big gap between the available knowledge provided by current measurement and modeling tools and the knowledge which is required by policy makers and land managers. This thesis focuses on improving the knowledge of the effects of vegetation cover and land use on regional scale wind erosion. The thesis covers improvement of wind erosion measurement techniques (Chapters 2, 3 and 5) and wind erosion modeling on the regional scale

Mots Clés : vegetation - wind erosion - land degradation - modeling - models - measurement - arid lands

Présentation

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