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

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

The NC value diagram (Fig. 7) shows high ratio of native components (E+K) and only a few native disturbance tolérants (TZ) and weeds (GY) can be found in this community. Oalamagrosti-Salicetum cinereae This community often appears in marshes where the stagnant water level is high during almost all year around. The moisture and light conditions make possible the presence of species of shady forests and large numbers of mosses under the willow trees. In the upper part of the Koloska valley two larger stands of CalamagrostiSalicetum cinereae (D,E) can be found. The composition of these small forests is very diverse. The forest canopy consists of Salix fragilis and Salix cinerea. In the shrub layer a lot of species from the surrounding drier forest (Orno-Quercetum pubescenti cerris, Cotino-Quercetum) were observed e.g. Crataegus monogyna, Rosa canina, Cornus mas, Viburnum lantana). In the herb layer the elements of GlycerioSparganion and Magnocaricion are abundant, e.g. Lythrum salicaria, Eupatorium cannabinum, Lysimachia nummularia, Mentha aquatica, Carex acutiformis, Carex riparia. The W value diagram (Fig. 8 and 9) show that the lower W value (W=3, 4, 5) also plays an important role in the composition of these forests, in addition to the high proportion of W=9,

10 species. On the NC value diagram (Fig. 8 and 9) large % 50A0-30 20 10 htcd p. / 2 3 4 S 6 7 8 9 10 11 W 7060SOAO 30 20 10 JJ ! u KVV E K TP rzer 6 A AiC Fig. 8. W- and NC value scatter diagram of Calamagrosti-Salicetum cinereae (D) number of native disturbance tolérants (TZ) and weeds (GY) can be noted beside the native elements. These places seem to be drier and slightly disturbed due to the nearby tourist path. Colonization by species of dry forests is also a cause of the wide spectra of W values. The third major patch of Calamagrosti-Salicetum cinereae (G) is situated in the lower course of the stream. This is a typical stand of the Calamagrosti-Salicetum cinereae community. The tree layer consists of Sala cinerea and underneath young willow trees form the shrub layer. In the herb layer Carex acutiformis, Carex riparia, Equisetum palustre, Angelica sylvestris, Eupatorium cannabinum, Scrophularia