Lokhtin, Vladimir Mikhaylovich

(b.St.Petersburg, Russia, 1849;dPetrograd, Russia,(1919)

hydrotechnology,hydrology.

In 1875 Lokhtin graduated from the St. Petersburg Institute of Communications Engineers, after which he participated in surveys of the tributaries of the Kama River. In 1882 he was appointed head of a party to survey on the Dniester River, and after two years he was put in charge of improving navigation conditions on that river. From 1892 to 1899 Lokhtin, as head of the Kazan Communication District, led major research and corrective work on the Volga River near Nizhni Novgorod (now Gorki) and on a number of its shoals. In the early twentieth century he studied economic problems of water transport, and 1904 he participated in the study of the ice conditions of the Neva River. From 1907 he was inspector of macadam roads of Petersburg Province, and from 1915 he was a member of the Committee of State Construction and edited the journal Vodnye putt i slwsseynye dorogi (“Waterways and Macadam Roads”).

Lokhtin was one of the founders of the hydrology of rivers. The development of his theory on the formation of a riverbed may be followed from his work Reka Chusovaya (“The Chusovaya River” 1878) to the monograph O mekhanizme reclmogo rush (“On the Mechanism of a Riverbed”; 1895). In the first of these works Lokhtin, examining the peculiarities of the Chusovaya as a mountain stream, also touched on several general properties of rivers, the character of the changes in their velocities, their slopes, and the movement of high water. He turned his attention to the change in the transverse profile of the surface of the river during rises and fails in its level; on the basis of his observations, he asserted that a rise in level of the river produces a distended or convex profile while a fall in level leads to formation of a depression or concave profile.

Reports given by Lokhtin at the Russian Technical Society, Sovremennoe pohzhenie voprosa o sposohakh uluchshema rek (“The Present State of Methods of Improving Rivers”; 1883) and Sovremennoe sostoyanie voprosa ob izuehenii svoysiv rek (“The Present Condition of the Study of the Properties of Rivers”; 1884), represented a substantial contribution to the development of the theory of riverbed processes. In the former Lokhtin spoke of the incorrectness of the then prevalent idea of the parallel stream movement of water in rivers and advanced the theory of the inner displacement of water within the current, pointing out that such a displacement explains the spiral movement of water, which determines the form of the riverbed. He did not, however, develop the question of the spiral form of movement or a liquid. In this report Lokhtin spoke of the three elements—climatic conditions, the character of the soil, and the topography of the basin—that determine the peculiarities of each river.

Lokhtin developed his original ideas of the processes which take place in riverbeds, particularly the formation of shoals, spits, and islands, in a work published in 1886, “Reka Dnestr, ee sudokhodstvo, svoystva i uluchshenie” (“The River Dniester, Its Navigation, Properties, and Improvement”). He connected the redistribution of slope between the reach and the shoal portions at the times of low and high water and the formation of shoals with three factors: the longitudinal profile of the riverbed (the influence of rocky “strong points”), the arrangement of the river in the plane (the influence of curvature), and the width of the river (influence of local widening). Referring to the shoal-reach form of the river, Lokhtin wrote that the low-water reaches and shoals are the result of the action of energetic high water—a result so considerable that weak and brief low waters are not strong enough to erase it or modify it. Lokhtin explained the formation of spits, and then of islands, as the result of the filling up of excess widths by sediment at the time of high water.

The fullest expression of Lokhtin’s views on riverbed processes occurs in his monograph O mekhanizme reclmogo rush (“On the Mechanism of a Riverbed”; 1895). It should be noted that in their theories other authors of works on the formation of riverbeds did not take into account the essential consideration that the discharge and level of water in rivers is not constant and can change within considerable limits. They made their generalizations fit chiefly the low-water situation. Moreover, a large range of variation in level is characteristic of the Russian rivers of the plains, which are fed primarily by melted snow. (During spring floods the majority of large Russian rivers rise more than three meters: on the Volga the rise reaches ten-thirteen; on the Don, seven-ten; on the Dnieper, six-eight.)

According to Lokhtin, the character of each river is determined by the following elements, each of which is independent of the others: (I) the amount of water, determined by sedimentation in the basin, and the soil conditions of the basin; (2) the slope or steepness, determined by the topography of a local cross section of the river; and (3) the degree of erosion or stability of the river channel, which depends on the properties cut into it by the flow of the bottom layers. Since all these elements can be present in different degrees and in different combinations, studying the character of a given river requires a knowledge of the physical and geographical conditions of the basin. The equipment which Lokhtin had at his disposal did not permit him to discover the inner structure of the current, determined by the turbulence and action of the centrifugal and Coriolis forces; he regarded the current as alTected only by the action of gravity and as counterbalancing the resistance arising from the friction of water against the bottom.

Having examined and compiled longitudinal profiles of the free-water surfaces of the Volga, Dniester, and Garonne rivers at high-water and low-water levels, Lokhtin noted that the slope of the water surface at the transition from high water to low water changes at the same places in such a way that in the reaches it becomes less, and at the shoals more, than it was at high water. From this it follows that at low water, as a result of the increase in the longitudinal slope at the shoals—and thus also of the velocity of the current— the deposits which accumulate at times of high water or flood are eroded and carried to lower-lying reaches, where at low water the slope and velocity of the current decrease. Lokhtin wrote:

Having in its fall a single force for carrying away the obstructions which constantly enter the river and sensing an inadequacy in this force, in comparison with the resistance of the deposits, the river, so to speak, economizes the force, concentrating it at the place where, considering this, it rs at a given time most necessary. At high water the slope is concentrated at the reaches, so that, cleaning them of deposits, it can go over, when the water level falls, to the shoals and begin carrying away the deposits which were temporarily left there at high water because of a lack of strength. Thus both parts of the riverbed, reaches arid shoals, are inevitable and necessary in the Attraction of deposits and are, in addition, definitely limited and constantly keep their places corresponding to the organically essential local conditions of the riverbed [O meklumizme rechnogo rusla, p. 33].

Lokhtin classified rivers as stable or unstable. He considered a stepped longitudinal profile of the water surface to be characteristic of stable rivers. Between stable and unstable rivers are those of intermediate character. Unstable rivers, according to Lokhtin, are characterized by a uniform slope of the longitudinal profile of the water surface and by continuous movement of bottom sediments along the whole river. For a measure of the stability of the river, Lokhtin proposed the expression

representing the ratio of the mean diameter of the section of the bed to the fall of the water surface. Lokhtin concentrated his analysis of riverbed phenomena on the stable river bed. He believed that rivers could be improved through engineering methods based on the degree of stability of the river. (Although several inadequacies are now apparent in Lokh tin’s discussions of separate river phenomena, the basic elements of his theory of formation of riverbeds are still significant.)

Lokhtin’s research on the formation of ground ice is of considerable interest. He ascertained the presence of ice crystals at all depths of the current, which showed that they are formed in the open portions of the river as a result of the contact of flowing water with frosty air.

BIBLIOGRAPHY

I. Original Works. Lokhtin’s writings include Reka Chusovaya (“The Chusovaya River”; St. Petersburg, 1878); “Reka Dnestr, ee sudokhodstvo, svoystva i uluchshenie” (“The Dniester River, Its Navigation, Properties, and Improvement”), in Inzhener (1886), no. 9–10, 410–441, no. 11–12, 485–546; Smremennoe polozhenie voprosa o sposobakh uluchshema rek (“The Present State of Methods of Improving Rivers”; St. Petersburg, 1886); O mekhanizme rechnogo rusla (“On the Mechanism of a Riverbed”; Kazan, 1895), also translated into French (Paris, 1909); and Ledyanoy nanos i zimnie zatory na r. Neve (“Ice Deposits and Winter Ice Blocks on the Neva River”; St. Petersburg, 1906).

II. Secondary Literature. See I. A. Fedoseyev, Razvitie gidrologii sushi v Rossii (“Development of the Hydrology of Dry Land in Russia”; Moscow, 1960), pp. 105–106, 168–172; and A. K. Proskuryakov, V. M. Lokhtin i N. S. Lelyavsky Osnovateti uchenia o Jbrmirovanii rusla (“V. M. Lokhtin and N. S. Lelyavsky. Founders of the Theory of the Formation of the Riverbed”; Leningrad, 1951).

I. A. Fedoseyev