The Amu Darya (Amu river) is 2,580 km long and drains some 466,200 sq km of land. It is formed by the junction of the Vakhsh and Pandj rivers, which rise in the Pamir mountains of Central Asia.
It flows generally northwest, marking much of the northern border of Afghanistan with Tajikistan, Uzbekistan, and Turkmenistan before flowing through the Kara Kum desert of Turkmenistan and Uzbekistan, and entering into channels that flow into the Aral Sea basin (not the sea itself) through a large fertile delta. It flows swiftly until it reaches the Kara Kum where its course braids into several channels. The Amu Darya provides much needed water for irrigation, but this heavy draw on its water particularly in the last 50 years (as irrigated lands have expanded) has prevented the Amu Darya from replenishing the Aral Sea. The Kara Kum Canal c.800 km long carries water from the Amu Darya near Kelif across Southern Turkmenistan to Ashgabat and supplements the flow of the Tejen and Murgab rivers. The Amu Darya is paralleled by the Trans-Caspian Rail Road, which lessened the river's importance as a transport route.
The Amu Darya in ancient times was known in Greek and Latin as the Oxus and in Arabic as the Jayhunand. It figured importantly in the history of Persia, Sogd and Bactria and in the campaigns of Alexander the Great and was long regarded historically as the southern boundary of Transoxiana.
The Amu Darya rises in a number of turbulent headwaters; the Panj whose tributaries include the Vaksab, the Pamir Darya, the upper Morgab, and the Kulab Darya which is the source of the river. In the 9th/15th century the upper course of the river was thought to be the Vaksab, though today it is considered to be the Morgab.
The headwaters have been explored only since the 19th century, and the details provided secondhand by the 4th/10th-century Arab geographers do not accord with what is now known. Estakri named six streams, of which only the Vaksab is readily identifiable; others count the “river of Kundoz” (Dergam, Aq Saray) among the headwaters. The last stream to join the river (on the right), 1,175 km from its mouth, is the Sorkan Darya; several other rivers end in the desert before reaching the Amu Darya.
North of Balk the river enters the desert and flows on without tributaries, losing much water through evaporation. The Qara Qum lies on the left bank, to the southwest; and the Qızıl Qum stretches to the northeast, from the right bank.
The Amu Darya then flows in a northwesterly direction towards the Aral Sea; the river-mouth widenin near modern city of Nukus. The Khanates of Khiva and Bukhara lay along the lower course of the river to the 19th and early 20th centuries; in the south, the Amu Darya marked the Russo-Afghan frontier since the treaties of 1886-93, from Basaga in the west 1,100 km to Qaḷʿa-ye Panj in the east. Parts of the lower course of the river today serve as a boundary between Turkmenistan and Uzbekekistan.
The middle reaches of the Amu Darya are 3,570-5,700 m in width and from 1.5-8 m in depth, and are often in spate from April or May to July. The land along its banks, particularly the left bank has been periodically cultivated since the medieval period.
The mountainous upper reaches sometimes freeze over in winter, as do the delta and the lower course from the end of December to the end of March, to a depth of 30 cm on average.
Beyond the town of Kalef, the Amu Darya has changed its course over the centuries.
According to Ptolemy (in the 2nd century A.D.) and Biruni, the river flowed in a westerly direction from modern Kark/Kerki, not northwesterly as at present, and evaporated in the Qara Qum desert.
An ancient river bed can be detected, and still today the Amu Darya occasionally betrays a tendency to break its banks here and spill out to the left. But geological research has shown that the 350 m narrows near the modern town of Pitnyak are so old that the river cannot possibly have shifted its course there since the beginning of the known historical period.
Medieval irrigation canals, beginning just beyond the narrows, were built in the Khorezm region; canals still branch out in various directions, as far as the Soltan Uiz (Oways) Dag, and the rich agriculture of the region depends upon them.
Here, too, are located Janbas Qala, Toprak Qala, and the other pre-Islamic fortresses that were excavated by S. P. Tolstov starting in 1936.
In the 19th century it was suggested that the Amu Darya had flowed through the Ozboy into the Caspian Sea at the time of the Mongol conquest of Gorganj in 618/1221, and had turned back towards Lake Aral only about 1575.
W. Barthold tried to substantiate this thesis with historical evidence, but was disproved by Soviet geologists, who have shown that the Ozboy could never have been the lower reach of the Amu Darya, if only because of their relative size. Other evidence, including traces of the agricultural exploitation of the Ozboy bed in the medieval period, also contradicts Barthold’s view.
But still today the Amu Darya, particularly when in spate, sometimes extends a lateral channel (daryalıq) into the depression of Sarı Qamıs. The historical proofs adduced, themselves subject to varying interpretation, are not sufficient to outweigh the geological facts, yet certain zoological parallels between the Amu Darya and the Ozboy point to a connection between the two river systems, so the “Ozboy problem” is still being argued out amongst scientists.
Arab geographers refered to changes in the lower courses of the river near the Aral Sea; because of the silting up of river beds, the medieval Khwarazmian capital, Kat, was deserted, and the town of Gorganj was abandoned several times. These changes explain the rise of Khiva as the regional capital and the shifting dimensions of the delta (in Turkish Aral) that gives the sea its name.
In the 19th century the Russians settlers started to enlarge the use of the Amu Darya waters for large scale irrigation (for agricultural use) starting the process that has today resulted in the significant lowering of the level of the Aral.
Bibliography :
General: W. Barthold in EI1 I, pp. 339-42.A. Z. V. Toğan in İA I, pp. 419-26. Le Strange, Lands, pp. 433-45. Barthold, Turkestan3, pp. 64-179. B. Spuler, “Der Āmū Darjā. Eine Fluss-Monographie,” in Jean Deny Armağani, Ankara, 1958, pp. 231-48 (with more detailed bibliography). Idem in EI2 I, pp. 454-57. Bol’shaya Sovetskaya Entsiklopediya II, 1950, pp. 304-06 (with a map of the river). The upper reach: J. Markwart, Wehrōt und Arang, ed. H. H. Schaeder, Leiden, 1938. J. Wood, A Journey to the Source of the River Oxus, 2nd ed., London, 1872 (with a historical and geographical introduction by H. Yule). I. P. Minaev, Svedeniya o stranakh po verkhov’yam Amu Dar’yi, St. Petersburg, 1879. The Özboy problem: M. J. de Goeje, Das alte Bett des Oxus, Leiden, 1875. W. Barthold, Nachrichten über den Aralsee und den unteren Lauf des Amudarja, Leipzig, 1910. V. Lochtin, Reka Amu-Dar’ya i eyo drevnee soedinenie s Kaspiĭskim Morem, St. Petersburg, 1879. D. D. Bukinich, Starye rusla Oksa i Amu-dar’inskaya problema, Moscow, 1906. S. P. Tolstov, “Arkheologo-etnograficheskaya ekspeditsiya v Khorezm 1955/56 gg.,” Sovetskaya Arkheologiya, 1954-55, pp. 106-33 (also deals with the former course of the Oxus and Jaxartes). Geographical and geological information: Zapiski Imperatorskago Russkago Geograficheskago Obshchestva po obshcheĭ geografii IV, IX and XVII, XIV, XX, XXIII, St. Petersburg, 1877-81. L. A. Molchanov, “Proizkhozhdenie presnovodnykh ozyor Uzboya,” Izvestiya Gosudarstvennogo Gidrologicheskogo Instituta 13, 1929, pp. 43-57. A. S. Kes’, “Ruslo Uzboya i ego genezis,” Trudy Instituta Geografii Akademii Nauk SSSR 30, 1939. S. P. Tolstov, A. S. Kes’ and T. A. Zhdanko, “Istoriya srednevekovogo sarykamyshskogo ozera,” in Voprosy geomorfologii i paleografii Azii, Moscow, 1955, pp. 37-75.
