Kaszab Zoltán (szerk.): A Magyar Természettudományi Múzeum évkönyve 63. (Budapest 1971)
Fekete, G. ; Szujkó-Lacza, J.: A survey of the plant life-form systems and the respective research approaches III. Rankiaer's life-form conception. The application of life-forms in the characterization of phytoclimate and in vegetation analysis
III. A homogeneous or heterogeneous life-form system? The unequivocal definition of the life-form concept is not independent of the homogeneity or heterogeneity of the life-form systems. CAIN and CASTRO'S (1959) statement, namely that the RAUNKIAER system is homogeneous, holds only for the original system (1904, 1907) and to the "main types of life-form", respectively. The modified RAUNKiAER-systems, now in general use, are heterogeneous. The heterogeneity can be traced back to RAUNKIAER himself, who writes of 10 main life-forms in his work published in 1907, among others of Epiphyton, Stem Succulent, Hydrophyton, and Helophyton, as life-form classes (1918; relegating to them 30 life-form subtypes). According to him: "The fact, that the main principle of division of the system of life forms is, and must be, established from a single point of view naturally does not exclude the possibility of taking into consideration, when so desired, any other adaptation, within the limits of the framework constructed". That RAUNKIAER established his 10 life-form classes may be explained by the fact that he was one of the best phytosociologists of his time, indeed surpassing it, interested therefore not merely in the adaptation of the plant to the macroclimate but also to the plant association and the habitat (life-forms E and HH). No wonder that BRAUN —BLANQUET had soon (1928) assimilated these heterogeneous lifeform classes for phytosociological purposes (by exchanging the division of the Phanerophytes according to the bud protection and deciduous—evergreen characteristics with an also heterogeneous aspect of classification; this is the cause why this very useful, and in horticultural practice well-proven, principle disappears without a trace in later coenological literature). One of the great hybrid life-form systems of subsequent times is linked with RÜBEL'S name (1930). One can also observe that no trace of also the Cryptophytes, as a uniform main type of life-form, can be found in numerous systems constructed for a coenological application. Contrarily, it is also characteristic of the other side that 5 main types of lifeforms are sufficient for WALTER (1960), of an analytico-ecological outlook. The latest example of the eclectical and heterogeneous "RAUNKIAER-type" life-form systems is ELLENBERG and MUELLER —DOMBOIS'S work (1967), compiled with a formation-descriptive purpose. According to ELLENBERB (1968): "Unter pflanzlichen Lebensformen versteht man Wuchsformen mit offensichtlichen Anpassungscharakter und Einfluss auf die Konkurrenzfähigkeit." It transpires from this definition that the adaptation, caused by diverse factors, of the plants may and can come into account in the system which might therefore best be called a system of "Wuchsformen" of identical life-form. Its "perfection" concurs with the increase of heterogeneity (the intermixture of "Wuchs"- and adaptational features) and formalism (containing categories whose existance in nature is not even certain). IV 7 . Distinguishing phytoclimates by life-forms Already in his work of 1907, RAUNKIAER emphasizes the importance of the life-forms with respect to the equiconditional regions which he calls phytoclimatic regions. He finds in this the main importance of the life-forms and attempts —partly on the basis of KOPPEN'S biochors, partly by analysing statistically the life-forms of species occurring in the diverse regions —the elaboration of a "biological plant geography" already in 1908. A standardized basis is indispensable for
