Life form (botany)

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Classification depending on the location of the renewal buds

Life form is a term used mainly in botany for organizational types of organisms that are characterized by the same structural, developmental, way of life or behavioral properties, through which they are adapted to certain environmental conditions of the habitat . A frequently used form of life system of plants is that of Christians Raunkiaer that the plants according to the position of their Überdauerungs buds divided. Other systems classify plants according to the water supply at their location, according to soil factors or according to diet. Life form and growth habit are often used synonymously.

Some authors differentiate between life form and life form type. The life form is the entire auto-ecological complex of structures and behaviors of an organism, while the life form type consists of all species that have developed a complex of similar structures due to their similar way of life.

Life forms according to Raunkiær

Classification according to Raunkiær

Raunkiær created a system of plant life forms in 1919 by grouping the species according to the location of their perennial buds. The system was created in Northern Europe and is now particularly widespread in Europe. The persistence of unfavorable seasons includes cold winters as well as dry seasons. After the system was expanded, for example by Ellenberg and Müller-Dombois (1967), the following forms of life exist:

  • Phanerophytes : Persistence buds more than 30 cm above the ground. These include above all the trees and bushes .
  • Chamaephytes have buds that are between one and 30 cm above the ground. As a result, the buds are usually protected from the snow and enjoy a microclimate close to the ground. These include dwarf shrubs and cushion plants .
  • Cryptophytes
  • Hemicryptophytes have their survival buds directly on the surface of the soil, so that they are protected by the layer of leaves. The buds are often located on the basal parts of the previous year's shoots.
  • Geophytes form organs and buds that are hidden in the soil and are therefore particularly well protected.
  • Therophytes are herbaceous species that bloom once ( hapaxanthe ), complete their life cycle in less than a year and do not form any permanent organs. The wintering takes place through the diaspores .
The Tillandsia landbeckii can be seen as an aerophyte , since the majority of the nutrients required are brought in from the air.

These life forms are all rooted in the ground and are summarized as radical edges. They are contrasted with other groups of plants that do not take root in the ground:

  • Adherent or adnate plants sit on top of other plants. They include epiphytes and various parasitic plants.
  • Movable or errant plants are the freely swimming and floating water plants .
  • Aerophytes are plants that get their nutrients from air and rainwater. They grow in often elevated locations where there is no soil substrate , such as rocks and sand dunes . As far as they grow on other plants, they also belong to the group of epiphytes . Aerophytes are perennial plants whose roots are poorly developed . Many species of the genus Tillandsia belong to this group.

Other systems

A distinction is made according to the water content of the location:

A distinction is made according to the soil factor:

A distinction is made according to the diet:

Table of common abbreviations for the types of life
Abbr. Life form
A. Hydrophyte
C. herbaceous chamaephyte
G Geophyte
H Hemicryptophyte
N Nanophanerophyte
P Phanerophyte
T Therophyte
Z woody chamaephyte
left Liana / spreading climber
ep Epiphyte
hp Semi-parasite
vp Full parasite

Web links

supporting documents

  • Manfred A. Fischer , Karl Oswald, Wolfgang Adler: Excursion flora for Austria, Liechtenstein and South Tyrol. 3rd, improved edition. Province of Upper Austria, Biology Center of the Upper Austrian State Museums, Linz 2008, ISBN 978-3-85474-187-9 , p. 107f.
  • Matthias Schaefer: Dictionary of Ecology . 4th edition, Spektrum Akademischer Verlag, Heidelberg, Berlin 2003, pp. 183f. ISBN 3-8274-0167-4

further reading

  • Christen C. Raunkiær: Types biologiques pour la geographie botanique. Overs. Kongl. Danske Vidensk. Selsk. Forh., 1905, pp. 347-437.
  • Christen C. Raunkiaer: The Life Forms of Plants and Statistical Plant Geography being The Collected Papers of C. Raunkiaer . Oxford, 1934.
  • H. Ellenberg, D. Müller-Dombois: A key to Raunkier plant life forms with revised subdivisions . Ber. Geobot. 37: 56–73, Inst. ETH Rübel Foundation, Zurich 1967.

Individual evidence

  1. ↑ Galán de Mera, A., MA Hagen & JA Vicente Orellana (1999) Aerophyte, a New Life Form in Raunkiær's Classification? Journal of Vegetation Science 10 (1): 65-68
  2. ↑ D. Benkert: Ellenberg, H .; Weber, HE; Düll, R .; Wirth, V .; Werner, W .; Paulissen, D .: Pointer values ​​of plants in Central Europe (Scripta Geobotanica; 18). 3. improve and exp. Ed. 248 p., 38 ill. Verlag Erich Goltze KG, Göttingen, 1991. ISBN 3-88452-518-2. Price: DM 29.90 . In: Fedde's repertory . tape 104 , no. 3-4 , May 1993, ISSN  0014-8962 , pp. 284-285 .