Straight-line non-branching channels: morphological diversity and typifi cation

   Relatively straight non-branching channels account for the smallest share among all morphodynamic types of channels, which is due to the instability of the rectilinear flow movement. Recently they have become objects of study from the point of view of their morphology, dynamics and conditions of formation, including on particular rivers, due to the difficulties arising in solving water management and water transportation problems. Despite their apparent uniformity and relatively weak intensity of channel reformations, they are characterized by certain morphological variability associated mainly with the parameters of the channels, their water content, and specific conditions of formation. Rectilinear channels could form an independent type and associated morphologically homogeneous sections in a wide-floodplain, adapted and incised channel. They could also occur in the form of small sections (“insertions”) between adjacent bends in a meandering channel, in floodplainchannel branches, in the branches of conjugated and single branchings. Rectilinear “insertions” are an integral part of complex chest (trapezoidal) bends, in which they separate the upper forced bend of the channel on the approach to the leading bedrock bank or the ledge of a high, rarely flooded floodplain, and the lower bend with an upper wing near the bedrock bank. Taking into account all factors, a complete classification of rectilinear channels has been elaborated. The conditions of their formation and specific features of their deformations have been defined, as well as possibilities of the optimal management of channel processes to ensure the stability of waterways and hydraulic structures, and the operation of water management facilities.

1. Baker V.R. Stream-channel response to floods with examples from central Texas, Geol. Soc. Am. Bull., 1977, vol. 88, no. 8, p. 1057–1071.

2. Callander R.A. Instability in river channels, Field mech., 1969, vol. 36, p. 465–480.

3. Chalov R.S., Chalov S.R. The morphology of the rocky channel of the Angara River in its stretches within the Boguchanskoye and Motyginskoye reservoirs, Geography and Natural Resources, 2009, no. 1, р. 47–53.

4. Chalov R.S., Golubtsov G.B., Kurakova A.A. Razvetvleniya rechnykh rusel, ikh morfologicheskie proyavleniya i tipizatsiya [Formation of river channel branches, their morphology and typing], Izvestiya RGO, 2023, vol. 155, no. 3–4, р. 145–162. (In Russian)

5. Chalov R.S. Izvilistost’ ili razvetvlennost’ potoka i formirovanie meandriruyushchikh i razvetvlennykh na rukava rechnykh rusel [Sinuos or braiding water flows and formation of meandering and braided river channels], Vest. Mosk. un-ta, Ser. 5, Geogr., 2021, no. 3, р. 3–12. (In Russian)

6. Chalov R.S. Ruslovedenie: teoriya, geografiya, praktika, vol. 1, Ruslovye protsessy: faktory, formy proyavleniya i usloviya formirovaniya rechnykh rusel [Riverbed studies: theory, geography, practice, vol. 1, Riverbed processes: factors, forms of manifestation and conditions of formation of riverbeds], Moscow, LKI Publ., 2008, 608 p. (In Russian)

7. Chalov R.S. Ruslovedenie: teoriya, geografiya, praktika, vol. 2, Morfodinamika rechnykh rusel [Riverbed studies: theory, geography, practice, vol. 2, Morphodynamics of riverbeds], Moscow, KRASAND Publ., 2011, 960 p. (In Russian)

8. Chernov A.V. Geomorfologiya poim ravninnykh rek [Geomorphology of floodplains of lowland rivers], Moscow, MSU Publ., 1983, 198 p. (In Russian)

9. Davis W.M. Meandering valleys and underfit rivers, Assoc. Am. Geogr., 1913, vol. 3, p. 3–28.

10. Dobrovol’skaya N.G. Osobennosti subakval’nogo vyvetrivaniya na ravninnykh i gornykh rekakh (na primere Leny i Kara-Bau, zapadnyi Tyan’-Shan’) [Specific features of subaqueous weathering on plain and mountain rivers (case studies of Lena and Kara-Bau rivers, western Tien Shan)], Vest. Mosk. un-ta, Ser. 5, Geogr., 1980, no. 2, р. 71–76. (In Russian)

11. Fargue L. La forme du lit des rivers a fond milife, Paris, 1908, 187 p.

12. Golubtsov G.B. Formirovanie, morfologiya i dinamika ostrovov shirokopoimennykh rusel bol’shikh rek (na primere Obi i Leny) [Formation, morphology and dynamics of islands in wide floodplain channels of large rivers (case studies of the Ob and Lena rivers)], Extended Abstract of Ph.D. Thesis in Geography, Moscow, IG RAS Publ., 2023, 29 p. (In Russian)

13. Grishanin K.V. Teoriya ruslovogo protsessa [Riverbed process theory], Moscow, Transport Publ., 1972, 216 p. (In Russian)

14. Ivanov V.V. Usloviya formirovaniya, gidrologo-morfologicheskie zavisimosti i deformatsii otnositel’no pryamolineinykh nerazvetvlennykh rusel [Conditions of formation, hydrological and morphological dependencies and deformations of relatively straight unbranched channels], Extended Abstract of Ph.D. Thesis in Geography, Moscow, MSU Publ., 1989, 23 p. (In Russian)

15. Karasev I.F. Ruslovye protsessy pri perebroske stoka [Channel processes during runoff transfer], Leningrad, Gidrometeoizdat Publ., 1975, 288 p. (In Russian)

16. Kargapolova I.N. Reaktsiya rusel rek na izmeneniya vodnosti i antropogennoe vozdeistvie za poslednie stoletiya [Response of river beds to changes in water content and anthropogenic impact over the past centuries], Extended Abstract of Ph.D. Thesis in Geography, Moscow, MSU Publ., 2006, 27 p. (In Russian)

17. Komar P.D. Shape of streamlined island on Earth and Mars: Experiments and analyses of the minimum-drag form, Geology, 1983, no. 11, p. 651–654.

18. Kondrat’ev N.E., Lyapin A.N., Pin’kovskii S.I. i dr. Ruslovoi protsess [Riverbed process], Leningrad, Gidrometeoizdat Publ., 1959, 372 p. (In Russian)

19. Kondrat’ev N.E., Popov I.F., Snishchenko B.F. Osnovy gidromorfologicheskoi teorii ruslovogo protsessa [Fundamentals of the hydromorphological theory of the channel process], Leningrad, Gidrometeoizdat Publ., 1982, 282 p. (In Russian)

20. Lin’ Chen’kuan’. Klassifikatsiya tipov rusel, Vest. Nankin. un-ta, 1963, № 1. (In Chinese)

21. Makkaveev N.I. Ruslo reki i eroziya v ee basseine [Riverbed and erosion in its basin], Moscow, AN USSR Publ., 1955, 347 p. (In Russian)

22. Makkaveev N.I. Stok i ruslovye protsessy [Runoff and riverbed processes], Moscow, MSU Publ., 1971, 116 p. (In Russian)

23. Parker G. On the cause and characteristic scales meandering and braiding rivers, Field mech., 1976, vol. 76, p. 457–480.

24. Popov I.V. Metodicheskie osnovy issledovaniya ruslovogo protsessa [Methodological principles of studying the riverbed process], Leningrad, Gidrometeoizdat Publ., 1961, 208 p. (In Russian)

25. Proektirovanie sudovykh khodov na svobodnykh rekakh [Design of shipping lanes on free rivers], tr. TsNIIEVT, iss. 36. Moscow, Transport Publ., 1964, 262 p. (In Russian)

26. Rozovskii M.L. Dvizhenie vody na povorote otkrytogo rusla [Movement of water at a turn in an open channel], Kiev, AN USSR Publ., 1957, 188 p. (In Russian)

27. Ruslovoi rezhim rek Severnoi Evrazii [Channel regime of the rivers of Northern Eurasia], R.S. Chalov (еd.), Moscow, MSU Publ., 1994, 316 p. (In Russian)

28. Ruslovye protsessy i vodnye puti na rekakh Obskogo basseina [Channel processes and waterways on the rivers of the Ob River basin], R.S. Chalov, E.M. Pleskevich, V.A. Baulа (еds.), Novosibirsk, RIPEL-plyus Publ., 2001, 300 p.

29. Ruslovye protsessy na rekakh SSSR, Karta [Channel processes on the rivers of the USSR, Map], M1: 4 000 000, R.S. Chalov (еd.), Moscow, GUGK USSR Publ., 1990, 4 р.

30. Rzhanitsyn N.A. Rusloformiruyushchie protsessy rek [Channel-forming processes of rivers], Leningrad, Gidrometeoizdat Publ., 1985, 264 p. (In Russian)

31. Schumm S.A. The fluvial system, John Wiley and Sons, New York, 1977, 338 p.

32. Shen’ Yuichan, Gun Goyuan’. Rechnaya geomorfologiya. Pekin, Nauka Publ., 1986. (In Chinese)

33. Sidorchuk A.Yu. [The main forms of river channels: meanders and branches], Voprosy geografii, рt. 140, Sovremennaya geomorfologiya [Modern Geomorphology], Moscow, Kodeks Publ., 2015, р. 319–340. (In Russian)

34. Zamyshlyaev V.I. [Mathematical model of planned reformation of river channels], Tr. GGI [Proceedings of the State Hydrological Institute], 1983, iss. 288, р. 53–72. (In Russian)

35. Zamyshlyaev V.I. [On the lateral stability of a straight riverbed], tr. GGI [Proceedings of the State Hydrological Institute], 1982, iss. 278, р. 48–55. (In Russian)

36. Zhukovskii N.N. [Review of the main phenomena of natural formation of a river bed (excerpts from the work “On the organization and system of dredging in the transit of rivers with a moving bed”)], Volzhskoe zemlecherpanie i ego dostizheniya. Voprosy gidrotekhniki svobodnykh rek [Volga River dredging and its achievements. Issues of hydraulic engineering of free rivers], Moscow, Rechizdat Publ., 1948, р. 329–363. (In Russian)