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

Titre : SAND STABILIZATION BY AFFORESTATION IN AL HASSA OASIS, SAUDI ARABIA

Auteur : Abo Hassan, Atalla Ahmed

Etablissement de soutenance : Michigan State University

Grade : Doctorat 1976

Résumé
Al Hassa, an important agricultural oasis in eastern Saudi Arabia, is threatened by moving sand dunes from the north. In the past the loss of cultivated land to the moving sand had averaged more than two hectares per year. In 1962, the Sand Control Project was initiated by the Ministry of Agriculture and Water in Saudi Arabia to stop the sand’s progress, protect the cultivated land at the oasis and its water resources, improve climatic conditions, improve the status of the people living in the oasis, and encourage them to increase their cultivated land. Early efforts at controlling the moving sand included mechanical and physical methods. The mechanical methods included transposing and trenching. In transposing, the sand dunes in a particularly threatened area were moved by trucks or other means to other locations. In trenching, the sand dune surface was scarred with a bulldozer to destroy its symmetry, so that the moving sand would accumulate in the trenches. These methods did not prove feasible for large scale application. Physical stabilization methods included covering the sand with asphalt, high gravity oil, mud, a combination of rubble and cement, mud and rubble, and concrete. Generally these methods proved to be unsatisfactory. A common problem was that each of these materials was easily broken by animals and vehicles and also cracked and fell into fragments in a short time because of high soil surface temperatures. Also, they were expensive and needed to be repeated quite often ; therefore, they are not applicable for large scale stabilization. Among agricultural methods that were tried, sowing grass was effective but slow and expensive, so it was discontinued. Afforestation, both with and without irrigation was also attempted beginning in 1963. This study was conducted at the Al Hassa Sand Control Project in eastern Saudi Arabia, to evaluate sand stabilization by afforestation methods. Initially, six species were used : Tamarix aphylla, Tamarix gallica, Acacia cyanophylla, Parkinsonia aculata, Prosopis juliflora and Eucalyptus camaldulensis. These species are drought resistant, saline tolerant, and they can withstand the wide air and soil temperature extremes that often occur.

Annonce (Dar Almandumah)

Présentation et version intégrale