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TARIM
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TARIM , the See also:principal See also:river of See also:Chinese or Eastern See also:Turkestan, in the See also:middle of See also:Asia. It rises in two See also:head-streams, (I) the See also:Kashgar-darya, which springs as the Kyzyl-su on the N. versant of the Pamir See also:plateau, not far from another Kyzyl-su or the Vakhsh, which flows down the Alai valley to join eventually the Amu-darya, and (2) the Yarkand-darya, which gushes out under the name of the Raskan-darya, on the N. slope of the See also:Karakorum Mountains, just under the Karakorum pass. The fo.mer stream flows almost due E. past the See also:city of Kashgar until it joins the Yarkand or Yarkent-darya. The latter, after skirting, in a deep See also:gorge and in a See also:north-western direction, the S. See also:foot of the Sughet Mountains and then of the Raskem Mountains, both constituent members of the western Kuen-lun, forces its way out into the lowlands of Eastern Turkestan and flows N. past the city of Yarkand, then turns N.E. and traverses in a gigantic arc the N.W., N., and E. margins of the vast See also:desert of Takla-makan. Of these two streams Dr Sven Hedin concedes the See also:honour of being the See also:mother river to the Yarkand-darya, on the ground both of its length and of its See also:volume; indeed for some months in the See also:year the Kashgar-darya, mainly owing to the drain made upon it for See also:irrigation purposes after it debouches upon the lowlands, fails to get through to the Yarkand-darya, whereas the Yarkand-darya, on the other See also:hand, never dries up. The Kashgar-darya enters the Yarkand-darya by a wide See also:delta of anastomosing arms, beginning in the vicinity of Maral-bashi (39° 49' N. and 78° 33' E.). The conjoint river, bearing the name of the Yarkand-darya, flows for some 230 m. N.E. until it encounters the Ak-su-darya from the N. Along this See also:part of its course the river is full of See also:minor sinuosities, with a deep, narrow channel, a sluggish current, and high steep See also:banks, bordered by forests of poplars and thickets of reeds. The Ak-su-darya, which rises at an See also:altitude of I I,000 ft. as the Ak-sai near the S.W. extremity, but on the W. See also:side, of the Kokshal-tau range of the Tian-shan Mountains, soon breaks through that range and proceeds to flow E.N.E. along its See also:southern foot, but under the name of the Taushkan-darya, until it reaches the See also:town of Ak-su in 8o° 41' E. and 4o° 28' N. Thence it flows S. and S.E. and effects a junction with the Yarkand-darya (Tarim) in about 81° E. The Ak-su, which is See also:swift and brings down large quantities of sediment, infuses new vigour into the See also:main river, giving it an impulse which carries it all the way down to the Kara-koshun. About 20 m. farther down, the Yumalak-darya or Tarim, as the river then begins to be called, is joined on the right or S. by the See also:Khotan-darya, a stream which rises in the N. ranges of the Kuen-lun Mountains, and fights its way across the all-engulfing sands of the desert of Takla-makan, but with such poor results that it is only about See also:forty days in the year that it makes any contribution to the volume of the Tarim. Some 18o to 190 m. below the confluence of the Ak-su-darya, the river begins to come into See also:direct conflict with the See also:sand-See also:dunes of the See also:great desert, which it has thus far successfully skirted. At the same See also:time it begins to See also:waste its strength in filling marginal or lateral lakes, formed in the hollows between the big sand-dunes (they reach elevations of as much as 3oo ft.). In about 86° 30' E., near the station of Karaul, the river begins to break up in deltaic See also:fashion, and in a See also:long See also:secular See also:process, using Karaul as a sort of See also:pivot, appears to oscillate backwards and forwards like a pendulum from N. to S., and from S. back again to N. between the See also:lake of Kara-koshun (N. M. Przhevalsky's Lop-nor) at the N. foot of the Astin-tagh (see LOP-NOR), and the See also:basin at the S. foot of the Kuruk-tagh (see See also:Goal), which See also:Baron von See also:Richthofen and Dr Sven Hedin identify with the See also:ancient Lop-nor of the old Chinese geographers. From Karaul down to Ayrilghan or Arghan, a distance of over 200 m., the Tarim skirts the N.E. front of the high sand-dunes of the great desert, spending itself in numerous marginal lakes all the way down, while on the opposite See also:bank (See also:left) Dingley See also:tariff of 1897. it leaves numerous interlacing branches behind it, like the Kunchekish-tarim, Lashin-darya, Yatim-tarim, llek, and Tokuz-tarim. None of its marginal lakes is See also:round in shape, but all are elongated, from N. to S. or from N.W. to S.E. This is the See also:general See also:rule, but there is a second See also:series of lakes beside the river which are See also:drawn out from N.E. to S.W. These owe their existence primarily to the See also:action of the See also:wind. Here too, in its delta, the Tarim overflows into more than one See also:chain of a third See also:category of lakes (e.g. Avullukol, Kara-kol, Tayek-kol, and Arka-kol), strung on one or other of its anastomosing deltaic arms. These generally See also:act as regulators and clarifiers, the river emerging from them with crystal-See also:bright See also:water. Near the head of its delta the Tarim is joined from the N. by the Koncheh-darya, a stream which issues from the lake of Bagrash-kul, its ultimate source being the Khaidu-gol or Khaidyk-gol, which drains the Yulduz valleys of the eastern Tian-shan Mountains. This river, which See also:measures 290 in. from the Bagrash-kul to the Kara-koshun, serves, with the help of the See also:poplar See also:forest which grows along its left bank, as a See also:dam to check the westward See also:movement of the desert sands. Finally the Tarim enters, by a number of arms, the series of shallow, dwindling lakes of Kara-buran, which serve as a sort of lacustrine ante-See also:room to the real terminal basin of the river, the Kara-koshun, which lies a little farther to the E., in 40° N., 89° 30' E., at an altitude of 2675 feet above See also:sea-level. In 1900-01 Dr Sven Hedin discovered several fresh desert lakes forming to the N. of Kara-koshun, and branches of the deltaic arms of the Tarim, or overflows of such branches, straining out in the same direction, facts which he interpreted as a tendency of the river to revert to its former more northerly terminal basin of the old (Chinese) Lop-nor. The river not only dwindles vastly between the confluence of the Ak-su (e.g. 16,78o cub. ft. in the second in See also:June) and its embouchure in the Kara-koshun (5650 cub. ft. in the second), but keeps on lifting its See also:bed and its current, like the Po and the Hwang-ho, above the level of the adjacent See also:country. The See also:total fall from the confluence of the Ak-su-darya (3380 ft.) to the Kara-koshun (2675 ft.), a distance of some 665 m., is only 705 ft., giving an See also:average of very little more than a foot per mile. The total length of the river is probably somewhere near woo m. On the whole the Tarim is step by step and year by year steadily but slowly working its way towards the S.W., for all along its See also:lower course it is accompanied by a See also:belt, some 5o m. wide, which lies at a lower level or altitude than itself. In its actual delta this tendency is See also:counter-balanced by its incipient oscillation backwards towards the N., towards the desiccated lake basin of the old Lop-nor. Although the river drains the vast See also:area of 354,000 sq. m., it is only from 172,000 sq. m. of this (48.8 per cent.) that it derives any See also:augmentation of volume. The remaining 182,000 sq. m. (51.2 per cent.) of the potential catchment area fails to contribute one drop of water, being nothing but arid, rainless desert. Throughout the catchment-basin of the Tarim the precipitation is governed by the general See also:law, that it increases from N. to S. and from E. to W. Hence, in conformity with this, the largest affluents are in the See also:west. In general shape the basin of the Tarim is elliptical, but the lowest part lies near the extreme E. end of the See also:ellipse. " If the deepest part of the basin See also:lay beyond the long See also:axis of the ellipse the symmetry would be ideal; but, situated as it is at the southern foot of the Tian-shan, it has occasioned a dislocation towards the N. of the main stream of the See also:system. . . . If we compare the See also:northern peripheral See also:zone from the catchment area of the Kashgar-darya to the catchment area of the Kuruk-tagh, both inclusive, with the southern peripheral zone from the catchment area of the Yarkand-darya to the catchment area of the Astin-tagh, both again inclusive, we find that the former has an area of 82,990 sq. m., and the latter an area of 89,550 sq. m., or, in other words, that they are approximately of the same See also:size. In the See also:case of both the breadth decreases on the whole towards the E., until they each terminate in a narrow See also:strip, the domain of the Kuruk-tagh on the one hand and that of the Astin-tagh on the other. But before they See also:contract in this way the zones swell out into the Khaidu-gol and the See also:Cherchen-darya and Kara-muran respectively. . A corresponding symmetry can also be seen in the See also:rivers which gather off the encircling mountains into the depression," 1 the Kashgar-darya balancing the Yarkand-darya, the Ak-su-darya balancing the Khotan-darya, the Koncheh-darya balancing the Cherchen-darya, and so on. The Tarim begins to freeze about the end of See also:November and the freezing advances upwards against the current. When the See also:ice of the river thaws in the beginning of See also: Additional information and CommentsThere are no comments yet for this article.
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