Mauritania has four ecological zones: the Saharan Zone, the Sahelian Zone, the Senegal River Valley, and the Coastal Zone. Although the zones are markedly different from one another, no natural features clearly delineate the boundaries between them. Sand, varying in color and composition, covers 40 percent of the surface of the country, forming dunes that appear in all zones except the Senegal River Valley. Fixed sand dunes are composed of coarse, fawn-colored sand, while shifting ("mobile") dunes consist of fine, dustlike, reddish-colored sands that can be carried by the wind. Plateaus generally are covered with heavier blue, gray, and black sands that form a crusty surface over layers of soft, loose sand.

Data as of June 1988

NOTE: The information regarding Mauritania on this page is re-published from The Library of Congress Country Studies and the CIA World Factbook. No claims are made regarding the accuracy of Mauritania Major Geographic and Climatic Zones information contained here. All suggestions for corrections of any errors about Mauritania Major Geographic and Climatic Zones should be addressed to the Library of Congress and the CIA.