Synusiae as a Basis for Plant Sociological Field Work

Recent publications of Lippmaa (1933a, b, 1935) have brought new emphasis to synusiae. His treatment of the vegetation of Esthonia and the Isalnd of Abruka (Abro) on the basis of his one-layered association concept is the first consistent handling of the vegetation of a region strictly based on synusiae. Gams (1918) first described the synusial system of biological units based on both plants and animals. Many plant sociologists have found that a consideration of the synusiae has clarified their concept of the phytocoenoses, the more complex, several-layered, vegetational units. Although many sociologists have described one-layered associations (along with many-layered associations), and certain authors have expressed ideas concerning plant associations which more or less approach Lippmaa's concept, it remained for Lippmaa to elevate the synusiae (homogeneous life-form communities) to the full rank of associations. This method results frequently in several associations occupying the same terrain simultaneously, in fact as many asociations as there are life-form groups in the phytocoenosis.