B. Papp szerk.: Studia Botanica Hungarica 30-31. 1999-2000 (Budapest, 2000)

Lőkös, László; Farkas, Edit: Contributions to the knowledge of lichens of the forests along the Fekete-Körös, SE Hungary

Studia bot. hung. 30-31, pp. 69-78, 1999-2000 CONTRIBUTIONS TO THE KNOWLEDGE OF LICHENS OF THE FORESTS ALONG THE FEKETE-KÖRÖS, SE HUNGARY L. LŐKÖS

1 and E. FARKAS

2 'Department of Botany, Hungarian Natural History Museum H1476 Budapest, Pf 222, Hungary institute of Ecology and Botany, Hungarian Academy of Sciences H-2163 Vácrátót, Hungary The lichen flora of the riverine forests along the Fekete-Körös (SE-Hungary) were studied in 1993 and 1998. About 400 records of 74 lichen species are listed from 42 forest stands of various tree species composition, sylvicultural management, age and size. Rare and interesting species are: Chaenolheca brachypoda, C. chrysocephala, C. trichialis, Dimerella pineti, Melanelia exasperata, Opegrapha vermicellifera, Parmelina pastillifera and Thelocarpon laureri. The most frequent species of these forests (Amandinea punctata, Xanthoria parietina, Physcia adscendens, Melanelia glabratula, Parmelia sulcata, Bacidia fraxinea) indicate strong anthropogenic influence. Key words: floristics, Hungary, lichens, riverine forests INTRODUCTION Relatively few lichens occur in inundation areas along the rivers in Hungary (GALLÉ 1962, \964a,b, 1965, 1966, 1967a,b, 1968, 1973,LAKI 1989, SOLYMOSI 1978). Certainly, one of the reasons is that the regular water cover or the floods causes unfavourable conditions for the colonisation or permanent existence of terricolous lichens. In lack of natural rocks, the saxicolous species can colonise only "artificial rocks" (concrete, tile, slate, brick, etc.), or other anthropogenic substrates like buildings, stone walls, embankments, etc. Epiphytic lichen species can survive permanently above the highest Hood level. They usually grow in the upper parts of the canopy relatively rich in light, especially on the upper surface of the horizontal branches. The bark of most of the trees in these areas (Juglans, Populus, Robinia, Salix, Sambucus, Ulmus) is regarded to be nutrient-rich, on which nitrophilous, more or less species-poor communities may appear in great abundance. The oak-ash-elm forests of higher elevations provide suitable biotops for a higher number of lichen species. Although there is a limited number of publications on the lichens (or botanical works with lichen data) of certain areas in Békés county (BORBÁS 1881, GALLÉ 1970, Kiss 1965, KOREN 1874,1883, VERSEGHY 1986), no lichenological records known from the riverine forests along the Fekete-Körös. Ádám Boros, who visited the area four times (1922, 1936, 1938 and 1957), made no report on li-