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
whose renovating bud projects during their entire life considerably above the surface of the soil —excel rather expressedly by their adaptation to the macroclimale or the air-space of the bioclimate (e.g. a forest). Such important adaptations are: bud protection, the deciduous or evergreen character (with a seasonal discontinuation of the assimilatory processes, excepting the equatorial tropical evergreens), strictly connected with the physiology of the plant in the unfavourable season. The grades of deciduous (or evergreen) character and those of bud protection may combine; nor is it indifferent from the life-form aspect to which unfavourable season (winter cold, summer drought) are these characters the results of adaptation. — In the Chamaephytes, the effects of microclimate are often intensified by special and extreme microclimate factors on the soil surface (added to the primary climatic effects; e.g. snow cover). The entire mass of the plant is exposed to these, therefore here the special structure of the shoots (e.g. suffruticose Chamaephytes; cushion plants: the mutual protection of densely arranged shoots with shortened internodia) is also a life-form feature, but only if the characteristics concur with a climatic correlation. — The problem of the hypogeous life-forms is more difficult. It is namely the most difficult to decide whether the innumerable shoot modifications of the Hemicryptophyton and Cryptophyton life-forms are the results of which effects inducing adaptation: climatic or edaphic, or whether they subserve the evolvement of competitive characteristics? In any case, the bud protection of the rosetted Hemicryptophyton life-form, among all such lifeforms adapted to the soil surface climate, is the strongest. — The several life-forms of the Cryptophytes are based in RAUNKIAER on the morphology of the vegetative organ, but the essence of the classification must not be morphologic. For instance, the essence of the rhizome-Geophytes should not be sought for in the morphology of the subterranean organ; the main thing is that they are able in the unfavourable season to select, by their rhizome, the most favourable soil depth for the overwintering buds. — The Therophytes, a group investigated recently by a number of research workers, will be discussed in a subsequent paper. The stability of the life-form should also be mentioned here. The life-form of very many species is a stabil, hereditary feature. Since, however, the life-form of a plant is a climatic adaptation, the same species may assume diverse life-forms in the diverse climates. [The Therophyton life-form species may appear in the life-form of a TH and a Hemicryptophyton, a Hemicryptophyton as a Geophyton, a Chamaephyton as a Nanopbanerophyton, indeed a Therophyton as a Chamaephyton (HAGERUP, 1930), cf. BRAUN —BLANQUET, 1951, UJVÁROSY, 1952, etc.]. These transitions point out the relationship of several life-forms. The life-form range of a species on the opposite poles of its areal borders refers Lo the plasticity, origin, and direction of evolution of the life-form (SEREBRIAKOV—SEREBRIAKOVA, 1967). These transitions follow from the continuous character and the homogradous and quantitative nature (cf. NUMATA, 1969) of the life-form (cf. our definition). As far as the second part of the definition is concerned, it is the root of the morphological adaptation, the more or less hereditary physiologico-biochemical integration of the climatic environment within the plant, now a recent task of modern life-form investigations (BURSTRÖM—KROGH, 1946; OIZUMI, 1951, 1952; KAZARIAN, 1959; BIEBL, 1962, etc.). We will return to this part of the definition later.
