B. Papp szerk.: Studia Botanica Hungarica 32. 2001 (Budapest, 2001)

Buczkó, Krisztina, Reskóné Nagy, Mária , Vinogradova, Oxana N.; Kiss, Gábor: The occurence of Aphanothece stagnina (Spreng.) A. Br. in Lake Velence, Western Hungary

places of the world, and reported the distribution of this species in the northern hemisphere. The pH of the soil samples that contained this taxon falls in the acidic category (4.56-6.02). It is a cosmopolitan species detected in soil samples from Europe, Africa, Asia and even Australia. (The humidity of the soil samples examined varied between 0.5 and 32.1%.) According to the measurements and data reports of the Central Danubian Environmental Protection Inspectorate, the once characteristic biological diversity of Lake Velence has begun to decline, the water bodies of differing qualities separated by patches of reed loosing their features and are on the way of homogenisation. This phenomenon is true for the entire lake. Aphanothece stagnina is one of a few algae which can be observed directly and visually and its occurrence easily mapped. Following some "confirmative identification", it may play a key role in the monitoring of the lake. * * * Acknowledgement - The collecting activities connected to BP were supported by the Hungarian Scientific Research Fund (OTKA grant No F5251). REFERENCES BARTHA, Zs. (1977): Phytoplanklon investigations on Lake Velence. (Algal counts and biomass.) Acta bot. hung. 23(1-2): 1-11. BARTHA, ZS. and HAJDÚ, L. (1979): Phytoplankton community structure studies on Lake Velence, Hungary. I. Diversity. - Acta bot. hung. 25(3-4): 187-222. BORICS, G., OLDAL, I., GRIGORSZKY, I., PADISÁK, J., PETERFI, L. I. and MOMEU, L. (1998): Adatok a Baláta-tó algaflórájához. (Data to the algal flora of the acidic bog lake Baláta-tó.) - Hidrológiai Közlöny 78: 276-278. FEHÉR, D. (1936): Untersuchungen über die regionale Verbreitung der Bodenalgen. - Arch. Mikrobiol. 7: 439-476. FEHÉR, D. (1948): Researches on the geographical distribution of soil microflora. II. The geographical distribution of soil algae. -MLÍSZ. Egy. Növényt. Intéz. Közi, Sopron (Hungary) 21: 1-37. FELFÖLDY, L. (1972): A kékalgák (Cyanophyta) kishatározója. - Vízügyi hidrobiológia 1, Vízügyi Dokumentációs és Tájékoztató Iroda, Budapest, 256 pp. KOMÁREK, J. and ANAGNOSTIDIS, K. (1999): Cyanoprocaryota. !. Teil Chroococcales. Süsswasserflora von Mitteleuropa 19/1. - Gustav Fischer Verlag, Jena-Stuttgart-Lubeck-Ulm, 548 pp. LAKATOS, GY. (1976): On the photosynthesis and chlorophyll efficiency in benthonic communities dominated by Vaucheria dichotoma Agh. in Lake Velence (Hungary). - Acta bot. hung. 22(3-4): 381-391. LAKATOS, GY. (1978): The phenomenon and significance of benthonic eutrophication in Lake Velencei, Hungary. - Acta Biol. Debrecina 15: 147-168.