Amur(redirected from Heilongjiang River)
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Amur(ämo͝or`), Chin. Heilongjiang, river, c.1,800 mi (2,900 km) long, formed by the confluence of the Shilka and Argun rivers, NE Asia, at the Russian-Chinese border; the Amur-Shilka-Onon system is c.2,700 mi (4,350 km) long. The Amur flows generally southeast, forming for more than 1,000 mi (1,610 km) the border between Russia and China, then NE through Russia before entering the Tartar Strait opposite Sakhalin island. Its chief tributaries are the Ussuri, Songhua, Zeya, and Bureya rivers. One of the chief waterways of Asia, the Amur is navigable for small craft for its entire length during the ice-free season (May–Nov.). The chief ports are the Russian cities of Khabarovsk (the head of large craft navigation), Komsomolsk, and Nikolayevsk.
(Mongol, Khara-Muren, “Black River”; Chinese, Heilung Kiang, “River of the Black Dragon”), a river of eastern Asia. The Amur basin lies in three countries: the USSR (Chita and Amur oblasts and Khabarovsk Krai), China, and the Mongolian People’s Republic. The major part of the basin, however, is within the USSR. In area (1,855,000 sq km) the Amur basin ranks fourth in the USSR (after the Enisei, Ob’, and Lena basins), and tenth in the world. The river is formed by the confluence of the Shilka and the Argun’ rivers, the point of formation being taken as the eastern end of Bezumnyi Island; the Amur discharges through the Amur estuary and the Sakhalin Gulf into the Sea of Okhotsk. The mouth of the Amur is considered to terminate at a line connecting Capes Ozerpakh and Pronge. The Amur is 2,824 km in length, or 4,440 km if the Argun’ River (Hailar) is included up to its source. The hydro-graphic network of the Amur embraces 10,610 rivers, of which 1,684 are less than 10 km in drainless Torreiskie Lakes). The Amur valley is basically the product of erosional processes whose general trend was determined technically. With regard to the structural features of the river valley, three basic regions can be distinguished. The Upper Amur (about 900 km in length), extending from the source to the city of Blagoveshchensk (mouth of the Zeia), lies in predominantly mountainous country. Up to the point at which the Amur is joined by its tributary Amuerkhe, the valley retains a well-defined character—relatively small hollows alternate with the narrow sections connecting them. Here the slopes of the valley are rocky, and high, and the current is quite rapid. On the right bank, spurs of the Bol’shoi Khingan Range approach close to the river. Below this point the Amur flows between the Amur-Zeia plateau and the Il’khuri Alin’ Range. The river valley broadens here, and developed meanders appear, such as the Korsakov Meanders, which are 45 km in length and only 0.6 km wide at the isthmus of the meander. The section of the river from Blagoveshchensk (at the mouth of the Zeia) to the city of Khabarovsk is about 1,000 km long; this section is called the Middle Amur. Here, at first, the river traverses the low portion of the Zeia-Bureia plain, then cuts through the Malyi Khingan Range, and emerges into the Middle Amur lowland. In this section, the speed of the current decreases, and the Amur assumes the features of a lowland river—wide valley, channel with low and sometimes marshy banks, and numerous islands and offshore banks. The channels formed by the islands and offshore banks are called razboi. Only below the mouth of the Bureia, where the Amur cuts through the Malyi Khingan Range, for a stretch of 150 km, does the river flow through a picturesque canyon, a single channel shaping the powerful flow of the stream. It is within the middle reaches that the Amur acquires the main volume of its flow, being joined here by all of its major tributaries—the Zeia and Bureia on the left bank, the Sungari and Ussuri on the right. The Lower Amur begins at the city of Khabarovsk. Here the valley is wide, as the stream passes through the Lower Amur lowland. The channel in this area is broken up into arms, and the broad floodplain contains numerous lakes. The water surface of the largest of these lakes (Bolon’, Udyl’, Orel’length, and 61,426 lakes, representing a water surface of 10,599 sq km (including the, Bol’shoi Kizi, and others) amounts to several tens of square kilometers; the various lakes are joined by channels with the Amur. The only sizable tributary in this region is the Amgun’ on the left bank, which joins the Amur at its mouth. Below the city of Nikolaevsk-na-Amure is the shallow Amur estuary which extends for 48 km. The main volume of flow of the Amur (two-thirds) derives from summer-autumn monsoonal rains; because of the scant winter snowfall, snow thaws produce only moderate spring high water, which directly precedes the main summer rise in water level. In April the Amur receives water from snow thaws on the plain and in May from thaws in the mountains. The lowest water levels occur at the end of winter. In the upper and middle courses of the river the water rises 10–15 m above the low-water level; it rises 6–7 m in the lower course. The water level rises four to six times each summer. At the mouth of the Amur there are tidal oscillations in water level amounting to 1.5–2.6 m. The upper course freezes first (at the beginning of November); the lower course freezes next (at the end of November). The ice begins to break up in the lower reaches of the river at the end of April and in the upper reaches at the beginning of May. In the spring when the ice drifts there are ice jams which cause a rise of up to 15 m in water level. Sometimes, when it rains heavily, there are immense floods on the middle and lower courses of the river; the floods are 10–25 km wide, last up to 70 days, and partially inundate large cities (Blagoveshchensk, Khabarovsk). The worst floods occurred in 1897, 1928, and 1956. The average annual volume of flow of the Amur is 343 cubic kilometers per year, or 10,800 cubic meters per second (cu m per sec); at Khabarovsk, the flow is 7,549 cu m per sec, and at Pokrovka (the source) it is 868 cu m per sec.
The Amur is navigable throughout its course and is an important waterway of the Soviet Far East. However, the channel is unstable, particularly in the lower course of the river, and annual dredging operations have to be carried out to maintain navigation. The Amur carries 41,000 tons of sediment a day. The major ports are Pokrovka, Blagoveshchensk, Leninskoe, Komsomol’sk-na-Amure, and Nikolaevsk-na-Amure (USSR) and Heiho (China). The Amur has significant resources of electric power. The total potential capacity of all the rivers of the Amur basin is estimated at 45 million kilowatts, not including 15 million kilowatts for industrial use. The Amur is the home of 99 different species of fish—the highest number in the USSR. The main fish caught are of the Salmonidae family (the keta and the humpback salmon). The fishing season is in summer and autumn. Other fish caught include silver carp, Huso dauricus, Erythroculter erythropterus, and sturgeon.
Russians first appeared on the Amur in 1644, when a party of cossacks headed by V. Poiarkov reached the river from Iakutsk, via the Lena, Aldan, and Zeia rivers. In 1649–51, E. P. Khabarov explored the Amur River and the Amur Region. In 1849–55, Captain G. I. Nevel’skoi made a thorough study of the Lower Amur. Systematic study of the water system of the river began in 1894–96; a network of gauging posts was set up, and a number of large expeditions were made (1901–09, 1927–29, 1932, 1935–36). From 1952 to 1958 the Academy of Sciences of the USSR conducted large-scale complex research in the region.
REFERENCESSokolov, A. A. Gidrografiia SSSR [2nd ed.]. Leningrad, 1964.
Davydov, L. K. Gidrografiia SSSR, part 2. Leningrad, 1955.
Stotsenko, A. V. Problema reki Amura i ego krupneishikh pritokov (Zeii, Bureii, Sungari, Ussuri). Vladivostok, 1958.
I. V. POPOV