Африка: География және жер бедері

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Africa is a continent comprising 63 political territories, representing the largest of the great southward projections from the main mass of Earth's surface. Within its regular outline, it comprises an area of , excluding adjacent islands. Its highest mountain is Kilimanjaro; its largest lake is Lake Victoria. Separated from Europe by the Mediterranean Sea and from much of Asia by the Red Sea, Africa is joined to Asia at its northeast extremity by the Isthmus of Suez (which is transected by the Suez Canal), wide. For geopolitical purposes, the Sinai Peninsula of Egypt – east of the Suez Canal – is often considered part of Africa. From the most northerly point, Ras ben Sakka in Tunisia, at 37°21′ N, to the most southerly point, Cape Agulhas in South Africa, 34°51′15″ S, is a distance approximately of ; from Cap Vert, 17°31′13″W, the westernmost point, to Ras Hafun in the Somali Puntland region, in the Horn of Africa, 51°27′52″ E, the most easterly projection, is a distance (also approximately) of The etchplains are commonly associated with laterite soil and inselbergs. Inselberg dotted plains are common in Africa including Tanzania, the Anti Atlas of Morocco, and the interior of Angola. One of the most wideaspread plain is the African Surface, a composite etchplain occurring across much of the continent. The area between the east and west coast highlands, which north of 17° N is mainly desert, is divided into separate basins by other bands of high ground, one of which runs nearly centrally through North Africa in a line corresponding roughly with the curved axis of the continent as a whole. The best marked of the basins so formed (the Congo Basin) occupies a circular area bisected by the equator, once probably the site of an inland sea. The following table gives the details of the chief mountains and ranges of the continent:

The upper Nile receives its chief supplies from the mountainous region adjoining the Central African trough in the neighborhood of the equator. From there, streams pour eastward into Lake Victoria, the largest lake in Africa (covering over 26,000 square m.), and to the west and north into Lake Edward and Lake Albert. To the latter of these, the effluents of the other two lakes add their waters. Issuing from there, the Nile flows northward, and between the latitudes of 7 and 10 degrees north it traverses a vast marshy level, where its course is liable to being blocked by floating vegetation. After receiving the Bahr el Ghazal from the west and the Sobat, Blue Nile and Atbara from the Ethiopian Highlands (the chief gathering ground of the flood water), it separates the great desert with its fertile watershed, and enters the Mediterranean at a vast delta. Great heat is experienced in the lower plains and desert regions of North Africa, removed by the great width of the continent from the influence of the ocean, and here, too, the contrast between day and night, and between summer and winter, is greatest. (The rarity of the air and the great radiation during the night cause the temperature in the Sahara to fall occasionally to freezing point.) Farther south, the heat is to some extent modified by the moisture brought from the ocean, and by the greater elevation of a large part of the surface, especially in East Africa, where the range of temperature is wider than in the Congo basin or on the Guinea coast. In the extreme north and south the climate is a warm temperate one, the northern countries being on the whole hotter and drier than those in the southern zone; the south of the continent being narrower than the north, the influence of the surrounding ocean is more felt. This disease has had a significant impact on African development not because of its deadly nature, like Malaria, but because it has prevented Africans from pursuing agriculture (as the sleeping sickness would kill their livestock).