VEGETATION OF TRAMPLED SOIL DOMINATED BY C4 PLANTS IN EUROPE

Plant communities of trampled soil dominated by plants characterized b y the C4-assimilation syndrome were investigated in Europe. These spec ies, belonging to genera such as Chamaesyce, Amaranthus, Eleusine, Era grostis and Setaria, are thermophilous, late-germinating, prostrate he rbs or grasses. The centre of their distribution is in the (Sub)Tropic s. A syntaxonomic revision of the phytosociological material from Euro pe (incl. the Macaronesian Archipelago) revealed three alliances: the Euphorbion prostratae from Spain, the Polycarpo-Eleusinion indicae fro m Italy, and Slovenian and Croatian Istria, and the Eragrostio-Polygon ion arenastri from temperate regions of Europe. The latter two syntaxa are described as new. All three alliances belong to the order Eragros tietalia (class Stellarietea mediae). Vicarious (ecologically analogou s) communities occur also in southern Africa, eastern Asia and North A merica. The communities studied in the present paper are considered to be an impoverished form of highly diversified trampled plant communit ies typical of (sub)tropical areas.