THIENEMANN, AUGUST FRIEDRICH

(b. Gotha, Germany, 7 September 1882;

d. Plön, Germany, 22 April 1960), limnology.

Thienemann was Europe’s leading limnologist (freshwater ecologist), being a productive author, director of a research institute, university professor, and editor of a leading scientific journal. He documented the life histories of aquatic insects, classified lakes according to their physico-chemical characterics and their biological productivity, promoted fish production, and by comparing northern European and tropical Indonesian lakes shed light on climatic influences on lake life.

Early Life and Career. August was the eldest of Carl Friedrich Thienemann and Emilie Noack Thienemann’s six children. His father and grandfather were prosperous book publishers and bookshop owners in Gotha. August could have followed in their footsteps. However, he developed an early love of nature and was an excellent student, and he attended the University of Greifswald, where he majored in zoology, with a strong interest in aquatic insects. He also spent semesters at the universities in Inns-bruck and Heidelberg (1903–1904), before receiving his PhD degree in 1905 from Greifswald.

He joined the faculty of the University of Greifswald for two years and then joined the Zoological Institute of the University of Münster in the Department for Fisheries and Waste Water for ten years. In the latter position he became involved in practical measures to promote fish production. In 1911 he married Siri Jönsson, who was Swedish, and they had two sons and three daughters. In 1914, he was called into the German Army as it mobilized for World War I. He was soon wounded in battle and was subsequently released from service.

In 1916, Professor Otto Zacharias, founder of the Hydrobiologische Anstalt at Plön, died, and in 1917 it became affiliated with the Kaiser Wilhelm Gesellschaft (later Max Planck Gesellschaft) and Thienemann became its director. Simultaneously, he joined the faculty of the University of Kiel and in 1924 became professor of hydrobiology. He was an excellent manager and a productive limnologist, publishing 460 works, including seven books (a limnology textbook, three brief popularizations of limnology, two lengthy monographs, and an autobiography). He remained director at Plön for forty years, retiring in 1957. He was also editor of Archiv für Hydrobiologie for more than forty years.

In April 1921, August and Siri Thienemann traveled to Sweden to attend her father’s funeral, and afterward they visited Einar Christian Leonard Naumann at the University of Lund, where he taught limnology and botany. The two limnologists had corresponded but had not previously met. Thienemann had a calm, friendly temperament, while Naumann was volatile and impulsive, but they quickly established a close working relationship.

Naumann, who was nine years younger than Thiene-mann, suggested that they establish an international society. Thienemann liked the idea, and they later developed a plan in their correspondence. Thienemann suggested using the term hydrobiology in the name of their organization, but Naumann preferred limnology, which emphasized the environment, and he prevailed. In January 1922 they sent a prospectus to over 100 colleagues, stressing the need for international cooperation to solve both practical and theoretical questions and asked for comments. There were 101 favorable responses, though eight declined to join (two for political and six for personal reasons). A Foundation Assembly was held at the University of Kiel, 3–5 August 1922, and Thienemann published the plans in Archiv für Hydrobiologie (1922). Coming less than four years after World War I, no one from France and only one from England joined then, but 188 joined from twenty-three countries. The Internationale Vereinigung für Limnologie (later called Societas Internationalis Limnologiae) had three goals: (1) embrace limnologists of all countries; (2) combine theoretical and applied aspects of freshwater research; and (3) bring together limnologists working in hydrographical and biological fields. Thienemann suggested that the society publish an annual yearbook of its proceedings (Verhandlungen), with lists of members and limnological research centers, and possibly reviews of current literature from different countries. The first volume of the Verhandlungen had 414 pages. Thienemann was elected chairman of the society and served until August 1939. Naumann was very active in it until he died in 1934, aged forty-three. In 1925 Thienemann and Naumann also started a monograph series, Die Binnengewässer, and Thienemann edited twenty of its volumes (writing three of them). At the society’s fiftieth anniversary in 1972, there were over 2,000 members from about sixty countries. Thienemann also developed an early interest in the history of biology and limnology, which he expressed in obituaries of limnologists published the Archiv für Hydrobiologie, the longest being on Naumann (1938).

Theoretical Concepts. Also in 1921 both Thienemann and Naumann published their separate research on the biological types of lakes. Their researches were complementary and became the foundation of “Seetypenlehre” (relating physico-chemical characteristics of lakes to their biological productivity), a dominant focus for limnological research. Naumann introduced into limnology the concepts of oligotrophy (little organic productivity) and eutrophy (much organic productivity); C. A. Weber (1907) had coined the terms to distinguish different peat bogs. Thienemann adopted these terms for clear lakes, and in 1925 he coined the term dystrophy (brown-water lakes with low lime content and high humus content) for oligotrophic humic lakes. In the same year H. Järnefelt coined the term mixotrophy (with phytoplankton absorbing organic nutrients from water) for eutrophic humic (with organic substances in a colloidal state) lakes. Thienemann’s studies of hypolimnon (deepest layer) fauna showed that species composition and populations depended on the oxygen content of the deepest layer of water. The Naumann-Thienemann lake classification was developed from the study of temperate lakes.

In 1928 and 1929 Thienemann was joined by Austrian limnologist Franz Ruttner and German zoologist H.

J. Feuerborn on an expedition to the Sunda Islands (Java, Sumatra, and Bali). They worked in the field for ten months, collected numerous animals, and later, with the help of more than one hundred specialists, described eleven hundred new species. Their important results were published in eleven supplementary volumes of Archiv für Hydrobiologie, 1931–1958. These findings led to a better understanding of variations in lake productivity in relation to climate. Thienemann was so fascinated by this experience that he devoted 132 pages of his autobiography to it.

The American zoologist Stephen A. Forbes wrote an influential essay in 1887, “The Lake as a Microcosm,” that attempted to explain the dynamic equilibrium of life in a lake. It appeared in an Illinois journal unlikely to reach Germany, and there is no evidence Thienemann saw it. Nevertheless, Thienemann used the same word, microcosm, to describe life in a lake, and he used the superorganism metaphor to describe the interacting species. His lake researches from the 1920s to 1950s led to three important ecological generalizations, the first two in the 1920s:

1. The more variable the biotope (=environmental) conditions in a locality, the greater is the number of species in the biocenosis (=biotic community).
2. The more biotope conditions deviate from the optimal for most species, the smaller the number of species are found there, but the greater the number of individuals which represent those species.
3. The longer a locality has remained in the same condition, the richer and more stable is its biocenosis.

In 1926 Thienemann first used the concepts of producers, consumers, and reducers to organize his biological data, and in 1931 he published a pioneering article on biological productivity. Raymond L. Lindeman, in his epochmaking article, “The Trophic-Dynamic Aspect of Ecology” (1942), was partly indebted to three of Thienemann’s papers. He cited Thienemann (1926) on the cycling of nutrients in water, and Lindeman’s diagram of the lacustrine system is similar to one in Thienemann’s paper.

During World War II, Thienemann remained active in limnological research, and he published about fifty scientific articles, which, however, found a smaller readership due to the war. Afterward he became alarmed at the decline in Europe’s environment. In 1955 he developed a six-point program that he continually preached for the rest of his life: the public should be informed about changes in supply and quality of natural waters; when changes are necessary, consult limnologists; water laws must be enforced; a river system should be managed in its entire length, regardless of administrative boundaries; hydroengineers must be taught ecological thinking; and theoretical water research is the basis of practice and needs increased support. Thienemann began planning a larger modern building for the Hydrobiologischen Anstalt of the Max Planck Gesellschaft in Plön before World War II, but the war delayed its implementation until 1961, after he had died.

BIBLIOGRAPHY

WORKS BY THIENEMANN

Die Binnengewässer Mitteleuropas: Eine Limnologische Einführung. Stuttgart, Germany: Verlag Schweizerbart, 1925.

“Der Nahrungskreislauf Im Wasser.” Verhandlungen Der Deutschen Zoologischen Gesellschaft 31 (1926): 29-79.

Verbreitungsgeschichte Der Süsswassertierwelt Europas. Die Binnengewässer, Band XVIII. Stuttgart, Germany: Verlag Schweizerbart, 1950.

Chironomus: Leben, Verbreitung Und Wirtschaftliche Bedeutung Der Chironomiden. Die Binnengewässer, Band XX. Stuttgart, Germany: Verlag Schweizerbart, 1954.

Erinnerungen und Tagebuchblätter eines Biologen: Ein Leben im Dienste der Limnologie. Stuttgart, Germany, 1959. A 500-page autobiography, which contains his complete bibliography and the best guide to his publications.

OTHER SOURCES

Elster, Hans-Joachim. “History of Limnology.” Mitteilungen Internationale Vereinigung für theoretische und angewandte Limnologie 20 (1974): 7–30.

Golley, Frank B. A History of the Ecosystem Concept in Ecology: More than the Sum of the Parts. New Haven, CT: Yale University Press, 1993. Discusses Thienemann’s contributions to developing the concept.

Lindeman, Raymond L. “The Trophic-Dynamic Aspect of Ecology.” Ecology 23 (1942) 399–418.

Macfadyen, Anyan. “The Meaning of Productivity in Biological Systems.” Journal of Animal Ecology 17 (1949): 75–80. Evaluated Thienemann’s contribution to productivity studies.

McIntosh, Robert P. The Background of Ecology: Concept and Theory. Cambridge, U.K.: Cambridge University Press, 1985.

Ohle, Waldemar. “August Thienemann 1882–1960: Sein Werk und Vermächtnis.” Archiv für Hydrobiologie 57 (1961): 1–12. Obituary.

Overbeck, Jürgen. “70 Jahre Seetypenlehre: Gedenktafel für August Thienemann.” Naturwissenschaftliche Rundschau 38 (1985): 58–60. Acknowledges the continuing influence of Thienemann’s work.

Rodhe, Wilhelm. “Crystallization of Eutrophication Concepts in Northern Europe.” In Eutrophication: Causes, Consequences, Correctives. Proceedings of International Symposium on Eutrophication, University of Wisconsin, 1967. Washington, DC: National Academy of Sciences, 1969. Discusses Thienemann’s role in developing a lake classification.

———. “The International Association of Limnology: Creation and Functions.” Mitteilungen Internationale Vereinigung fürtheoretische und angewandte Limnologie 20 (1974): 44–70. Both this and the president’s lecture describe Thienemann’s role in its founding.

———. “Limnology Turns to Warm Lakes.” Archiv für Hydrobiologie 73 (1974): 537–546. On the history of the Sunda Expedition of 1928–1929.

———. “President’s Lecture: The SIL Founders and Our Fundament.” Verhandlungen der Internationalen Vereinigung für theoretische und angewandte Limnologie 19 (1975): 16–25.

Steleanu, Adrian. Geschichte der Limnologie und ihrer Grundlagen. Frankfurt am Main, Germany: Haag + Herchen, 1989.

Frank N. Egerton