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

Vasas, Gizella: Contributions to the knowledge of macrofungi of the forests along the Fekete-Körös, SE Hungary

Studia bot. hung. 30-31, pp. 79-86, 1999-2000 CONTRIBUTIONS TO THE KNOWLEDGE OF MACROFUNGI OF THE FORESTS ALONG THE FEKETE-KÖRÖS, SE HUNGARY G. VASAS Department of Botany, Hungarian Natural History Museum H-1476 Budapest, Pf. 222, Hungary Mycological records to the riverine forests along the Fekete-Körös have been very limited. According to our recent investigations, the oldest, semi-natural stands of the Mályvád forest appeared to be the richest in species. Altogether, 90 macromycetes species were found; among them one species is new to science {Agaricus annulospecialis), and two species (Leiicoagaricus ionidicolor, Russula cicatricata) are new records for Hungary. Key words: Fekete-Körös, macrofungi, oak-ash-elm riverine forest THE STUDY AREA The area of the riverine oak-ash-elm forests and that of the extensive, dominant, natural oak forests of the Great Hungarian Plain have drastically been decreased in the past centuries due to the human activities, like river control, drainage, deforestation and afforestation by non-native species. By now only some semi-natural fragments remained in the Great Hungarian Plain, e.g. a considerable, less degraded stand in the once closed oakwoods at the Szatmár-Bereg Plain (NE Hungary), and a few more degraded stands along the Körös rivers (SE Hungary). Phytogeographically, the Körös-vidék belongs to the Crisicum (Tiszántúl) flora district and it extends up to the foothills of the Bihar Mts (Transylvania, Romania). For nature conservation, this area has great importance, because considerable oak-ash-elm forest stands (Fraxino pannonicae-Ulmetum), growing on alluvial soils, exist only here within the formerly considered "forest steppe zone" of the Great Hungarian Plain, and only here they are adjacent to the salty forests (Festuco pseudovinae-Quercetum). An important characteristics of these forests, their herbaceous layer is rich in submontane elements, due to the humid microclimate of the rivers and shaded forests. With increasing distance from the rivers the water-table is lowering, and more and more plant species characteristic of the dry oak forests (Quercetea pubescentis-petraeae s. I.) appear. The Mályvád forest, the largest, continuous forest area of the Fekete-Körös, was dominated by old, native trees. In recent decades, as the old (semi) natural stands had been harvested, these grand forests were gradually replaced by non-na-