Berg, Lev Simonovich

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Berg, Lev Simonovich

(b. Bendery, Bessarabia, Russia, 14 February 1876; d. Leningrad, U.S.S.R.,24 December 1950)

geography, ichthyology.

The son of Simon Gregor’evich Berg, a notary, and Klara L’vovna Bernstein-Kogan, Berg was was awarded the gold medal when he graduated from the Second Kishinev Gymnasium in 1894. He then enrolled in the natural science section of the Faculty of Physics and Mathematics at Moscow University. In 1898 he received the gold medal and a first-degree diploma in zoology for his paper “Droblenie yaitsa i obrazovanie parablasta u shchuki” (“The Breakdown of the Egg and the Formation of the Parablast in Pike”).

Striving to broaden his theoretical knowledge through practical work, Berg rejected an offer to remain at Moscow University and, having obtained the position of inspector of fisheries in the Aral Sea and on the Syr-Dar’ya River, he studied the lakes and rivers of central Asia and Kazakhstan for four years.

In 1902-1903 he was sent by the Russian Department of Agriculture to study oceanography in Bergen, Norway. Upon his return in 1904, Berg obtained the position of zoologist and director of the ichthyology section of the Zoological Museum of the Academy of Sciences in St . Petersburg, where he remained for ten years . In 1909 the degree of doctor of geography was conferred on Berg for his dissertation Aral’skoe more (“The Aral Sea”), for which he was also awarded the P.P. Semenov Gold Medal by the Russian Geographical Society. The following year Berg married Polina Abramovna Kotlovker, the daughter of a teacher, who bore him a son and a daughter . They were divorced in 1913, and in 1922 Berg married Maria Mikhailovna Ivanova, the daughter of a ship’s commander.

In 1913 the Moscow Agricultural Institute made Berg professor of ichthyology, and the following year he moved to Moscow. In 1917 Petrograd University appointed him professor of geography, and he spent the rest of his life there. In addition, Berg was simultaneously head of the applied ichthyology section of the State Institute of Experimental Agronomy, which was later renamed the Institute of the Fish Industry (1922–1934), and ichthyologist and head of the fossil fish section of the Zoological Institute of the Academy of Sciences of the U.S.S.R. (1934–1950). He also taught for several years at the Pedagogical Institute and the Geographical Institute.

In 1934 Berg was awarded the degree of doctor of zoology for his many important ichthyological investigations. In recognition of his outstanding scientific services, the Academy of Sciences elected him an associate member in 1928 and an academician in 1946. He was also awarded the titles Honored Scientist of the R.S.F.S.R.(1934) and Laureate of the State, first degree (1951). From 1940 to 1950 he was president of the All-Union Geographical Society. Among his awards were the Konstantinovsky Medal of the Russian Geographical Society (1915) and the Medal of the Asiatic Society of India (1936).

Berg’s works deal with a wide range of topics in geography and zoology. His early investigations were concentrated on the study of the lakes of northern Kazakhstan: the salinity of the water, the temperature regimen, the peculiarities of the shores, the fauna inhabiting them, and the origin of the lakes and all their components. Studying the changes in the mineralization of lakes, he put forth the notion (subsequently confirmed) that such changes occur because salts are carried away by the wind when the lakes temporarily decrease in size.

These detailed investigations, the beginning of limnology in Russia, gave Berg the basis for opposing the hypothesis popular at the end of the last century concerning the drying up of the lakes of central Asia. He convincingly demonstrated that these lakes do not dry up, but experience periodic fluctuations in their level and size that correspond to secular changes in climate and hydrological regimen.

Berg’s limnological investigations are recognized as classics. He considered a lake to be a geographical complex, taking into account the history of its formation, its connections with the surrounding territory, the peculiarities of climatic and hydrobiological regimens, and an evaluation of its economic importance as a reservoir. These works were intimately connected with observations of climate, for study of the history of lakes demonstrated the existence of a clear link between the hydrobiological regimen of a lake and paleoclimatic changes. Berg’s diversified works played an important role in the development of climatology as a science.

Berg’s contributions to ichthyology are extremely significant. His works contain valuable information on the anatomy, embryology, and paleontology, as well as on the systematics and geographical distribution, of all the fishes in the U.S.S.R. Of great scientific value are his studies of summer and winter spawning runs of migratory fish, the periodicity of fish reproduction and distribution, and the influence of climatic changes on fish migration. He also established the symbiotic relationship between the lamprey and salmon families, which arose as a result of similar conditions of existence.

Most significant of all Berg’s works are those on geography. Classifying the earth’s surface according to climatic, soil, biological, and other natural factors, he distinguished ten different geographical zones, several of which he divided into subzones. This system of zones followed a latitudinal sequence in lowland areas and a longitudinal one in mountainous areas. It contributed to the explanation of the surface characteristics of each area, ensuring detailed geographic study and the full exploitation of natural resources.

Berg opposed the opinion of some scientists that the earth’s climate was becoming drier, and, having analyzed a mass of geological, geographical, and historical material, he demonstrated that in the modern epoch the earth’s arid zones are contracting and that a displacement of zones is observable in the direction of the equator: the tundra is encroaching upon forest land, the forest is encroaching upon the steppe. On the other hand, equatorial forests are moving apart in the direction of the poles. This process was brought about, in Berg’s opinion, by general climatic fluctuations, determined by cosmic causes.

Berg distinguished geographical zones according to the principle of the uniformity of landscape: the relief, climate, plants, and soil combine into a unified, harmonious whole that typically is duplicated over an entire geographical zone. He examined landscapes as they developed and continually changed. By reconstructing the paleogeographic conditions, he sought to trace their transformation into the modern landscape zones.

During his study of landscape, Berg devoted much attention to a thorough study of soils, especially of loess. He concluded that loess originated as a result of the weathering of fine-grained calcareous rocks in a dry climate. This set of conditions, which arose in the southern part of European Russia after the Ice Age, led, in his opinion, to the rise of loess there. Analyzing the climatic peculiarities of the more remote geological past, Berg concluded that even before the Ice Age a geographical zonality had existed, and that there were seasonal rhythms and the alternation of dry and moist epochs. In any case, loess-type rocks had appeared in the Upper Paleozoic.

Berg coordinated his paleoclimatologic and paleogeographic reconstructions with the origin of various sedimentary rocks, the history of relief development, the formation of various soils, and the displacement of landscape zones. These investigations contributed to the intimate coordination of modern geography with historical geology. His works included separate statements about, and penetrating investigations of, the physicogeographical conditions on Precambrian continents, the origin of land and sea organisms, the development of floras and faunas, the influence of the Ice Age on the present distribution of plants, the origin of iron and bauxite ores, and some general laws of sediment formation.

Berg believed that with a change of geographical landscape there also occurred a change in the character of the sedimentary rocks; thus, no periodicity or cyclical recurrence in the formation of sedimentary rocks exists, inasmuch as landscapes are unique. He stressed the significance of living organisms in the migration of chemical elements and in the formation of sedimentary rocks. Since the organic world has been continuously transformed throughout the history of the earth, the sedimentary rocks associated with it can neither remain unchanged nor be cyclically repeated.

Berg took exception to the concept of a fiery liquid stage in the earth’s origin and supported the idea that the earth was initially solid. He also proposed that the position of the poles has changed little throughout geological history. On the basis of a biogeographic analysis, he determinedly spoke against Wegener’s theory and thought there are better data in favor of comparatively minor vertical movements of the earth’s surface than of its horizontal shifts for thousands of kilometers.

In his early papers Berg stated that great uplifts of the earth’s crust caused continental glaciations, but he later concluded that a change in solar activity or more remote cosmic processes were decisive factors in the origin of glacial epochs. In this way, regions of low temperature arose not only in mountainous or high-latitude regions but also in low-lying areas and in subtropic zones. This explains the bipolar distribution of many marine organisms.

The zoogeographical analyses completed by Berg, particularly that on the distribution of fish in the carp family, permitted him to determine with reasonable precision the time of the appearance of glacial epochs and the periods in which the climate grew warmer. Discussing the problem of the development of the organic world, Berg spoke about distinct boundaries between separate species and about a saltatory transition from some species to others.

In some of his papers Berg dealt with the origin of life on earth. He believed that the first organisms were autotrophic and needed neither oxygen nor light. They developed near the earth’s surface or in marshland. Subsequently, through their life processes, soils and atmospheric oxygen appeared and conditions were created for the transfer of life to the earth’s surface and the ocean. He believed that there were epochs when the formation of new species proceeded very intensively in all groups of living organisms.

In the last years of his life Berg devoted serious attention to the study of the history of geography and geographic discoveries, especially in Asia and the Antarctic.

Berg published about 700 works, including a number of monographs and textbooks. His name is perpetuated by a peak and a glacier in the southwestern Pamir, a glacier in the Dzhungarskiy Alatau Mountains, a volcano in the Kuril Islands, and a promontory in the Arctic.

BIBLIOGRAPHY

I. Original Works. Among Berg’s writings are Aral’skoe more. Opyt fiziko-geograficheskoj monografii (“The Aral Sea. A Physicogeographical Monograph”; St. Petersburg, 1908); Osnovy klimatologii (“Fundamentals of Climatology”), 2nd ed., rev. and enl. (Leningrad, 1938); Geograficheskie zony Sovetskogo Sojuza (“Geographical Zones of the Soviet Union”), 3rd ed., 2 vols. (Moscow, 1947–1952); Ryby presnykh vod SSSR i sopredel’nykh stran(“Freshwater Fish of the U.S.S.R. and Neighboring Countries”), 4th ed., rev. and enl., 3 vols. (Moscow-Leningrad, 1948–1949); and Izbrannye trudy (“Collected Works”), 5 vols. (Moscow-Leningrad, 1956–1962).

II. Secondary Literature. Works on Berg are Lev Semenovich Berg (1876–1950), Academy of Sciences of the U.S.S.R., Materials and Bibliography of Scientists of the U.S.S.R., Geographical Series, no. 2(Moscow-Leningrad, 1952); and E. Pavlovsky, ed., Pamjati akademika L.S. Berga. Sbornik rabot po geografii i biologii (“In Memory of L.S. Berg. A Collection of Papers on Geography and Biology”; Moscow-Leningrad, 1955).

V. V. Tikhomirov

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