Christen Christensen Raunkiær (29 March 1860 – 11 March 1938) was a

Danish Danish may refer to: * Something of, from, or related to the country of Denmark People * A national or citizen of Denmark, also called a "Dane," see Demographics of Denmark * Culture of Denmark * Danish people or Danes, people with a Danish ance ...

botanist Botany, also called , plant biology or phytology, is the science of plant life and a branch of biology. A botanist, plant scientist or phytologist is a scientist who specialises in this field. The term "botany" comes from the Ancient Greek w ...

, who was a pioneer of

plant ecology Plant ecology is a subdiscipline of ecology which studies the distribution and abundance of plants, the effects of environmental factors upon the abundance of plants, and the interactions among and between plants and other organisms. Examples ...

. He is mainly remembered for his scheme of plant strategies to survive an unfavourable season ("life forms") and his demonstration that the relative abundance of strategies in floras largely corresponded to the Earth's climatic zones. This scheme, the Raunkiær system, is still widely used today and may be seen as a precursor of modern plant strategy schemes, e.g.

J. Philip Grime John Philip Grime (30April 193519April 2021) was an ecologist and emeritus professor at the University of Sheffield. He is best known for the universal adaptive strategy theory (UAST) and the twin filter model of community assembly with Simon ...

's CSR system.

Life

He was born on a small heathland farm, named Raunkiær, in Lyhne parish in western Jutland, Denmark. He later took his surname after it. He succeeded Eugen Warming as professor in botany at the

University of Copenhagen The University of Copenhagen ( da, Københavns Universitet, KU) is a prestigious public university, public research university in Copenhagen, Copenhagen, Denmark. Founded in 1479, the University of Copenhagen is the second-oldest university in ...

and the director of the

Copenhagen Botanical Garden The University of Copenhagen Botanical Garden ( da, Botanisk have), usually referred to simply as Copenhagen Botanical Garden, is a botanical garden located in the centre of Copenhagen, Denmark. It covers an area of 10 hectares and is particular ...

, a position he held from 1912 to 1923. He was married to the author and artist Ingeborg Raunkiær (1863–1921), who accompanied him on journeys to the West Indies and the Mediterranean and made line drawings for his botanical works. They divorced in 1915, the same year as their only son Barclay Raunkiær died. Raunkiær later married the botanist Agnete Seidelin (1874–1956). Raunkiær's research axiom was that everything countable in nature should be subjected to numerical analysis, e.g. the number of male and female catkins in

monecious Plant reproductive morphology is the study of the physical form and structure (the morphology) of those parts of plants directly or indirectly concerned with sexual reproduction. Among all living organisms, flowers, which are the reproductive st ...

plants and the number of male and female individuals in dioecious plants. Raunkiær also was an early student of

apomixis In botany, apomixis is asexual reproduction without fertilization. Its etymology is Greek for "away from" + "mixing". This definition notably does not mention meiosis. Thus "normal asexual reproduction" of plants, such as propagation from cuttin ...

in flowering plants and hybrid swarms. In addition, he studied the effect of

soil pH Soil pH is a measure of the acidity or basicity (alkalinity) of a soil. Soil pH is a key characteristic that can be used to make informative analysis both qualitative and quantitatively regarding soil characteristics. pH is defined as the ne ...

on plants and plants on soil pH, a work his apprentice

Carsten Olsen Carsten Erik Olsen (1 March 1891 – 19 August 1974) was a Danish plant ecologist and plant physiologist, who pioneered the study of plant nutrition in soils of different pH. Biography He was born in Copenhagen and began studies of botany at t ...

continued. After his retirement, C. Raunkiær made numerical studies of plants and flora in the literature ("The flora and the heathland poets", "The dandelion in Danish poetry", "Plants in the psalms"). In these studies, he applied strict quantitative criteria, like in his ecological studies. For example, he defined a poet as a person who has written 1,000 or more lines of verse.

Legacy

Life form spectra

Raunkiær devised a system for categorising plants by life-form as a way of ecologically meaningful comparison of species and vegetation in regions having different

flora Flora is all the plant life present in a particular region or time, generally the naturally occurring ( indigenous) native plants. Sometimes bacteria and fungi are also referred to as flora, as in the terms '' gut flora'' or ''skin flora''. ...

s. Raunkiær compared statistically local life form spectra (relative abundance) with the world average, which he called "the normal spectrum" (Raunkiær 1918 – see below). Thereby, he devised the first null model in the history of ecology. Raunkiær was a keen naturalist, who described the

and fungi of Denmark, the Virgin Islands, Tunisia, and other countries. In contrast to many contemporary naturalist, however, he strongly promoted quantitative and numerical approaches and experimentation. He devised a method to quantify the abundance of plants in vegetation as frequency in subplots and used it for quantitative studies of a range of plant communities.

Raunkiær's law

When plotting the number of species in a plant community that fell in each 20-percentile frequency class from very frequent, i.e. numerically dominant, to very infrequent, Raunkiær discovered that most species were either very common or very rare. This came to be known as "Raunkiær's law" and is related to R. A. Fisher's logseries distribution and to Frank W. Preston's lognormal distribution of the number of individuals of each species in a community. The significance of his idea was, however, disputed already by some of his contemporaries.

Leaf size in plant geography

As a further experiment in characterizing plant communities, Raunkiaer devised a numerical scheme based on leaf size classes and leaf type (simple or

compound Compound may refer to: Architecture and built environments * Compound (enclosure), a cluster of buildings having a shared purpose, usually inside a fence or wall ** Compound (fortification), a version of the above fortified with defensive struc ...

) that was extended by L. J. Webb and is used as a way to classify forest types more simply than by lists of component species.

Popular References

Farley Mowat Farley McGill Mowat, (May 12, 1921 – May 6, 2014) was a Canadian writer and environmentalist. His works were translated into 52 languages, and he sold more than 17 million books. He achieved fame with the publication of his books on the Ca ...

, in his book, Never Cry Wolf, described using a Raunkiær's Circle in making a “cover degree” study to determine the ratios of various plants one to the other. He spoke of it as "a device designed in hell."

Scientific publications

* Raunkiær, C. (1887) Frøskallens Bygning og Udviklingshistorie hos Geraniaceerne. Botanisk Tidsskrift 16, 152-167. * Raunkiær, C. (1888–89) Myxomycetes Daniae eller Danmarks Slimsvampe. Botanisk Tidsskrift 17, 20-105 Description in English of some new and of some unsatisfactorily known species of Myxomycetes described in the preceding treatise. Botanisk Tidsskrift 17, 106-110. * Raunkiær, C. (1889) Notes on the vegetation of the North-Frisian Islands and a contribution to an eventual flora of these islands. Botanisk Tidsskrift 17, 179-196. * Raunkiær, C. (1893) Vegetationsorganernes Morphologi og Biologi hos de danske Cyperaceer - Bestøvning og Frugtsaetning hos de danske Cyperaceer. Botanisk Tidsskrift 18, 19-23. * Raunkiær, C. (1895) De danske Blomsterplanters Naturhistorie. l. Enkimbladede. Gyldendalske Boghandels Forlag, København. * Raunkiær, C. (1901) Om Papildannelsen hos Aira caespitosa. Botanisk Tidsskrift 24, 223-238. * Raunkiær, C. (1902) Statistisk Undersøgelse over Forholdet mellem Han- og Hunrakler hos vore Alnus-arter. Botanisk Tidsskrift 24, 289-296. * Raunkiær, C. (1903) Anatomical Potamogeton-Studies and Potamogeton fluitans. Botanisk Tidsskrift 25, 253-280. * Ostenfeld, C.H. & Raunkiær, C. (1903) Kastreringsforsøg med Hieracium og andre

Cichorieae The Cichorieae (also called Lactuceae) are a tribe in the plant family Asteraceae that includes 93 genera, more than 1,600 sexually reproductive species and more than 7,000 apomictic species. They are found primarily in temperate regions of the E ...

nglish summary Botanisk Tidsskrift 25, 409-413. * Raunkiær, C. (1904) Comment les plantes géophytes à rhizomes apprécient la profondeur où se trouvent placés leurs rhizomes. Oversigt over Det

Kongelige Danske Videnskabernes Selskab {{Infobox organization , name = The Royal Danish Academy of Sciences and Letters , full_name = , native_name = Det Kongelige Danske Videnskabernes Selskab , native_name_lang = , logo = Royal ...

s Forhandlinger, 1904, 330-349. * Raunkiær, C. (1904) Om biologiske typer, med hensyn til planternes zilpasninger til at overleve ugunstige aarstider. Botanisk Tidsskrift 26, XIV. THIS PAGE DOES NOT CONTAIN A PAPER BY RAUNKIAER WITH THAT TITLE NOR DOES THE ENTIRE VOLUME. Ch. 1 in Raunkiær (1934): Biological types with reference to the adaption of plants to survive the unfavourable season, p. 1. * Raunkiær, C. (1905) Types biologiques pour la géographie botanique. Oversigt over Det

s Forhandlinger, 1905, 347-438.THIS PAGE RANGE SEEMS DOUBTFUL, BUT IS REPEATED ON UMPTEEN ONLINE PAGES. * Raunkiær, C. (1905) Om Talforholdene mellem Kønnene hos tvebo Planter og om Talforholdet mellem hanlige og hunlige individer i Afkommet af Hunplanter og tvekønnede Planter hos Gynodiøcister. Botanisk Tidsskrift 26, 86-88. * Raunkiær, C. (1906) Edderkopper og blomsterbesøgende Insekter. Botanisk Tidsskrift 27, 313-316. * Raunkiær, C. (1906) Sur la transmission par hérédité dans les espèces hétéromorphes. Oversigt over Det

s Forhandlinger, 1906, 31-39. * Raunkiær, C. (1907) Planterigets Livsformer og deres Betydning for Geografien. Gyldendalske Boghandel - Nordisk Forlag, København and Kristiania. 132 pp. Ch. 2 in Raunkiær (1934): The life-forms of plants and their bearings on geography, p. 2-104. * Raunkiær, C. (1907) Om Livsformen hos Tussilago farfarus. Et lille Bidrag til Følfodens Naturhistorie. Botanisk Tidsskrift 28, 210. Ch. 3 in Raunkiær (1934): The life-form of Tussilago farfarus, p. 105-110. * Raunkiær, C. (1908) Livsformernes Statistik som Grundlag for biologisk Plantegeografi. Botanisk Tidsskrift 29, 42-43. German translation: Statistik der Lebensformen als Grundlage für die biologische Pflanzengeographie. Beiheft zum Bot. Centralbl., 27 (2), 171-206 (1910). Ch. 4 in Raunkiær (1924): The statistics of life-forms as a basis for biological plant geography, p. 111-147. * Raunkiær, C. (1908) Fungi from the

Danish West Indies The Danish West Indies ( da, Dansk Vestindien) or Danish Antilles or Danish Virgin Islands were a Danish colony in the Caribbean, consisting of the islands of Saint Thomas with ; Saint John ( da, St. Jan) with ; and Saint Croix with . The i ...

collected 1905-1906. Botanisk Tidsskrift 29, 1-3. * Raunkiær, C. (1909) Livsformen hos Planter paa ny Jord.

s Skrifter - Naturvidenskabelig og Mathematisk Afdeling, 7.Rk., 8, 1-70. Ch. 5 in Raunkiær (1934): The life-forms of plants on new soil, p. 148-200. * Raunkiær, C. (1909a) Formationsundersøgelse og Formationsstatistik. Botanisk Tidsskrift 30, 20-132. Ch. 6 in Raunkiær (1934): Investigations and statistics of plant formations, p. 201-282. * Raunkiær, C. (1911) Det arktiske og antarktiske Chamaefyteklima. In: Biologiske Arbejder tilegnede Eug. Warming paa hans 70 Aars Fødselsdag den 3. Nov. 1911. Kjøbenhavn. Ch. 7 in Raunkiær (1934): The Arctic and Antarctic chamaephyte climate, p. 283-302. * Raunkiær, C. (1912) Measuring-apparatus for statistical investigations of plant-formations. Botanisk Tidsskrift 33, 45-48. * Raunkiær, C. (1913) Formationsstatistiske Undersøgelser paa Skagens Odde. Botanisk Tidsskrift 33, 197-243. Ch. 8 in Raunkiær (1934): Statistical investigations of the plant formations of Skagens Odde (The Skaw), p. 303-342. * Raunkiær, C. (1914) Sur la végétation des alluvions méditerranéennes françaises. Mindeskrift i Anledning af Hundredeaaret for Japetus Steenstrups Fødsel (eds H. F. E. Jungersen & E. Warming), pp. 1–33. København. Ch. 9 in Raunkiær (1934): On the vegetation of the French mediterranean alluvia, p. 343-367. * Raunkiær, C. (1916) Om Bladstørrelsens Anvendelse i den biologiske Plantegeografi. Botanisk Tidsskrift 34, 1-13. Ch. 10 in Raunkiær (1934): The use of leaf size in biological plant geography, p. 368-378 * Raunkiær, C. (1916) Om Valensmetoden. Botanisk Tidsskrift 34, 289-311. * Raunkiær, C. (1918) Om Løvspringstiden hos Afkommet af Bøge med forskellig Løvspringstid nglish summary On leaftime in the descendants from

beech Beech (''Fagus'') is a genus of deciduous trees in the family Fagaceae, native to temperate Europe, Asia, and North America. Recent classifications recognize 10 to 13 species in two distinct subgenera, ''Engleriana'' and ''Fagus''. The ''Engle ...

es with different leaftimes]. Botanisk Tidsskrift 36, 197-203. * Raunkiær, C. (1918) Recherches statistiques sur les formations végétales. Biologiske Meddelelser /

, 1 (3), 1-80. Ch 11 in Raunkiær (1934): Statistical researches on plant formations, p. 379-424. * Raunkiær, C. (1918) Über das biologische Normalspektrum. Biologiske Meddelelser /

, 1 (4), 1-17. Ch. 12 in Raunkiær (1934): On the biological normal spectrum, p. 425-434. * Raunkiær, C. (1918) Über die verhältnismässige Anzahl männlicher und weiblicher Individuen bei Rumex thyrsiflorus Fingerh. Biologiske Meddelelser /

, 1 (7), 1-17. * Børgesen, F. & Raunkiær, C. (1918
Mosses and Lichens collected in the former Danish West Indies
Dansk Botanisk Arkiv 2 (9): 1-18. * Raunkiær, C. (1919) Über Homodromie und Antidromie insbesondere bei Gramineen. Biologiske Meddelelser /

, 1 (12), 1-22. * Raunkiær, C. (1920) Egern, Mus, og Grankogler. En naturhistorisk Studie. Biologiske Meddelelser /

, 2 (4), 1-90. * Raunkiær, C. (1920) Om Kryptogamernes Betydning for Karakteriseringen af Planteklimaterne. Botanisk Tidsskrift 37, 151-158. Ch. 13 in Raunkiær (1934): On the significance of Cryptogams for characterizing Plant climates, p. 435-442. * Raunkiær, C. (1922) Forskellige Vegetationstypers forskellige Indflydelse paa Jordbundens Surhedsgrad (Brintionkoncentration). Biologiske Meddelelser /

, 3 (10), 1-74. Ch. 14 in Raunkiær (1934): The different influence exercised by various types of vegetation on the degree of acidity (Hydrogen-ion concentration), p. 443-487. * Raunkiær, C. (1926) Nitratindholdet hos

Anemone nemorosa ''Anemonoides nemorosa'' (syn. ''Anemone nemorosa''), the wood anemone, is an early-spring flowering plant in the buttercup family Ranunculaceae, native to Europe. Other common names include windflower, European thimbleweed, and smell fox, an al ...

paa forskellige Standpladser. Biologiske Meddelelser /

, 5 (5), 1-47. Ch. 15 in Raunkiær (1934): The Nitrate content of

growing in various localities, p. 488-516. * Raunkiær, C. (1926) Om danske Agropyrum-Arter. (Isoreagent-Studier II). Botanisk Tidsskrift 39, 329-347. * Raunkiær, C. (1926) Vegetationen paa Maglehøj (vest for Arresø) og lidt om vore Kaempehøjes Flora i det hele taget. Botanisk Tidsskrift 39, 348-356. * Raunkiær, C. (1928) Dominansareal, Artstaethed og Formationsdominanter. Biologiske Meddelelser /

, 7 (1), 1-47. Ch 16 in Raunkiær (1934): The area of dominance, species density, and formation dominants, p. 517-546. * Raunkiær, C. (1928) Myxomycetes from the West Indian Islands

St. Croix Saint Croix; nl, Sint-Kruis; french: link=no, Sainte-Croix; Danish and no, Sankt Croix, Taino: ''Ay Ay'' ( ) is an island in the Caribbean Sea, and a county and constituent district of the United States Virgin Islands (USVI), an unincor ...

, St. Thomas and St. Jan. Dansk Botanisk Arkiv 5 (16), 1-9. * Raunkiær, C. (1930) Variation hos Tussilago farfarus L. Botanisk Tidsskrift 41, 257-258. * Raunkiær, C. (1934) Om de danske Arter af

Stellaria media ''Stellaria media'', chickweed, is an annual and perennial flowering plant in the family Caryophyllaceae.Fernald, M. L. 1950. “Gray's Manual of Botany”. Eight Edition. American Book Company, New York, NY. 1632 pp. It is native to Euras ...

-Gruppen. Botaniske Studier, 1. haefte (ed C. Raunkiær), pp. 3–30. J.H. Schultz Forlag, København. * Raunkiær, C. (1934) The Life Forms of Plants and Statistical Plant Geography. Introduction by A.G. Tansley. Oxford University Press, Oxford. 632 pp. Collection of 16 of Raunkiær's publications plus one new. * Raunkiær, C. (1934) Botanical studies in the Mediterranean region. Ch. 17 in The Life Forms of Plants and Statistical Plant Geography, pp. 547–620. * Raunkiær, C. (1935) The vegetation of the sand dunes north of Sousse. Botaniske Studier, 3. haefte (ed C. Raunkiær), pp. 244–248. J.H. Schultz Forlag, København. * Raunkiær, C. (1936) The life-form spectrum of some Atlantic islands. Botaniske Studier, 4. haefte (ed C. Raunkiær), pp. 249–328. J.H. Schultz Forlag, København. * Raunkiær, C. (1937) Artstal, Artstaethed og Praedominanter i danske Plantesamfund. Botaniske Studier, 5. haefte (ed C. Raunkiær), pp. 357–382. J.H. Schultz Forlag, København. * Raunkiær, C. (1937) Hudcellepapiller hos

Carex arenaria ''Carex arenaria'', or sand sedge, is a species of perennial sedge of the genus ''Carex'' which is commonly found growing in dunes and other sandy habitats, as the species epithet suggests (Latin , "sandy"). It grows by long stolons under the so ...

. Botaniske Studier, 5. haefte (ed C. Raunkiær), pp. 329–336. J.H. Schultz Forlag, København. * Raunkiær, C. (1937) Life-form, genus area, and number of species. Botaniske Studier, 5. haefte (ed C. Raunkiær), pp. 343–356. J.H. Schultz Forlag, København. * Raunkiær, C. (1937) Plantago intermedia og

Plantago major ''Plantago major'', the broadleaf plantain, white man's footprint, waybread, or greater plantain, is a species of flowering plant in the plantain family Plantaginaceae. The plant is native to Eurasia. The young, tender leaves can be eaten raw, a ...

. Botaniske Studier, 5. haefte (ed C. Raunkiær), pp. 337–342. J.H. Schultz Forlag, København.

Reviews and biographies

* *
Biography by O.G. Petersen in: Dansk Biografisk Lexikon, 1st edn 1887-1905 (ed. Carl Frederik Bricka)
* Biography by Carl Christensen in: Dansk Biografisk Leksikon, 3rd edn 1979-1984 (ed. Svend Cedergreen Bech).

References

External links

*http://www.wku.edu/%7Esmithch/chronob/RAUN1860.htm {{DEFAULTSORT:Raunkiaer, Christen C. 20th-century Danish botanists Danish ecologists Danish science writers University of Copenhagen faculty University of Copenhagen alumni 1860 births 1938 deaths Plant life-forms 19th-century Danish botanists