Introduction 



Libya is a vast expanse of semiarid and arid desert of variable 

 topography located in North Africa bordering on the Mediterranean 

 Sea. A large portion of the Libyan coastline follows the broad in- 

 dentation of the Gulf of Sirte. Libya is bordered on the east by Egypt 

 (United Arab Republic), on the southeast by the Sudan, and on the 

 west by Tunisia and Algeria. The republics of the Chad and Niger 

 form various portions of the southern marginal limits. The latitudinal 

 limits range from 19° north latitude at the extreme southeastern 

 portion to 33° north latitude at its northern extremity in Cyrenaica. 

 Longitudinally, Libya lies between 9° and 25° east longitude. This 

 large country comprises approximately 680,000 square miles of pri- 

 marily desert terrain and is divisible into three political provinces. 

 The province of Cyrenaica (approximately 330,000 sq. mi.) encom- 

 passes roughly the entire eastern half of Libya, and the provinces of 

 Tripolitania (approximately 136,000 sq. mi.) and Fezzan (approxi- 

 mately 213,000 sq. mi.) include the northwestern and southwestern 

 quadrants respectively. 



The surface configuration of Libya is quite varied with elevations 

 ranging from below sea level in the Sebchet el Gheneien near Gialo 

 and in the depressions surrounding Giarabub and Bahr el Tubat to 

 over 10,000 feet above sea level in the outliers of the Tibesti Mountains 

 of extreme southwestern Cyrenaica. In Libya, elevation tends to 

 increase gradually from north to south, the deserts of the interior 

 generally much higher than the coastal areas; a similar gradient in 

 elevation is seen in an east-west transect, the eastern portion ap- 

 preciably lower than the west. Abrupt local and regional changes in 

 relief occur throughout Libya owing to the juxtaposition of low-lying 

 plains, high plateaus, and mountain complexes. 



The pattern of vegetative cover in Libya follows rather closely the 

 physiographic features. The flora of the low-lying coastal plain is 

 particularly distinct from that of the pre-Saharan (steppe) and Saharan 

 zones of the interior. Likewise the Cyrenaican Plateau, because of its 

 higher elevation and more abundant rainfall, has a flora unlike that of 

 the coastal plain and interior deserts. 



Permanent vegetative cover of the Saharan interior of Libya is 

 sparse, and in large portions of the hamadas, serirs, and sand seas, it 

 is entirely lacking. Where vegetation occurs in these interior deserts, 

 it is usually either sporadic and tends to be localized in sandy de- 

 pressions of the hamadas, or occurs as narrow fringes bordering the 



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