L. Hably szerk.: Studia Botanica Hungarica 23. 1992 (Budapest, 1992)

Papp, Beáta: Phytocoenological survey along the Koloska stream (Balaton-felvidék region, Hungary)

RESULTS On the vegetation map (Fig. 2) the stands of the differentiated plant communities can be seen. A detailed description of each is presented below. Glycerio-Sparganietum This community can often be found by shallow, calcareous stream bed and along clear-water brooklets. Along the Koloska stream several well-developed stands of this association were observed. Two variants can be distinguished on the basis of species composition and abundance relations. A large spot of the Glycerio-Sparganietum var. typicum (A) is situated in the upper part of the valley. This stand consists of many species: Mentha longifolia, Eupatorium cannabinum, Scrophularia umbrosa, Sium erectum, Ranunculus repens, Lysimachia nummularia, Equisetum arvense are the most abundant ones. There is a striking dominance of Mentha longifolia. Lots of mosses grow by the small brooklets, e.g. Brachythecium rutabulum, Plagiomnium undulatum, Cratoneuron filicinum and Ambtystegium juratzkanum. A few individuals of Glyceria plicata, which is a characteristic species of this community, can also be found in this stand. The other characteristic species, Sparganium erectum is absent here, but it appears in the other variant (var. sparganietosum) of the Glycerio-Sparganietum (F, H) in the lower part of the valley. The W value diagram of this stand (Fig. 3) shows that it consists of species with different water requirements. Although there is a large number of high W value (W=8 and 9) species, many W=5 and 7 value species can also be found here. On the basis of the NC value diagram (Fig. 3), a high proportion (altogether above 50%) of disturbance tolérants (TZ) and weeds (GY) can be observed here beside the native components. Fig. 3. W- and NC value scatter diagrams of Glycerio-Sparganietum var. typicum (A) These facts can be explained by the mosaic structure of this area. The stream is divided into small brooklets, which enclose small drier outstanding spots, thus the microrelief is noticeably varied. The colonization of disturbance tolérants and