Kaszab Zoltán (szerk.): A Magyar Természettudományi Múzeum évkönyve 72. (Budapest 1980)

P. Komáromy, Zs.: Algae living on the shore of some Hungarian astatic salt lakes

ANNALES HISTORICO-NATURALES MUSEI NATIONALIS HUNGARICI Tomus 72. Budapest 1980. Algae Living on the Shore of Some Hungarian Astatic Salt Lakes by Zs. P.-KOMAROMY, Budapest Abstract — The algal flora of the shores of salt lakes near Fülöpháza and Fülöpszállás villages was investigated. The occurrence and the frequency of the species were examined as a function of distance from the water. The results were compared with the data of water algological examinations. The taxonomical investigations show that the algal flora of the areas is of blue-green type and the diatom species are rather common in the samples too. During the survey of the soil algal flora of the Kiskunság National Park (KOMÁROMY 1979) samples were taken at the shore of salt lakes in the neighbourhood of Fülöpháza and Fülöpszállás villages. Owing to their special origin and hydrobiological conditions they have a characteristic life community (Kiss 1975). This paper deals with algae occurring on the shore of lakes Kondor-tó, Szappan-szék, Szívósszék (or Zsíros-szék) and Kelemen-szék. The beds of these salt lakes, except Kelemen-szék, were shapen by the wind in the Holocene (MOLNÁR & SZÓNOKI 1975, MOLNÁR & MURVAI 1976). Kelemenszék is partly a river-bed, partly it is of deflational origin. The rain water and the infiltrate water accumulate in these deposits and thereby relatively extensive but shallow pools are formed. The mean depth of these waters is about 1 metre, and the quantity of their water, owing to intensive evaporation, is variable. Some of the lakes usually dry out in summer-time so the examined salt lakes are temporary (astatic) inland waters. On the other hand, owing to evaporation there is a strong daily and yearly fluctuation in the temperature and in the chemical conditions of the water. They are characterized by high salt concentration (18.000-32.000 mg/1) and alkalinity (pH 10-11). On the shore of the salt lakes ecologically we can distinguish well characterized areas as a function of distance from the water and on the basis of the small differences in the ground forms. According to the ecological nature, the periphery of the ponds may be divided into three areas: 1. littoral zone, characterized by Bolboschoenus maritimus; 2. transitional zone, with Juncus, Triglochin and/or Puccinellia limosa; 3. upper part of the shore where Agrostis alba, Cyrex disions and Aster tripolium are common (Table 1). From the littoral zone of the ponds 41 alga species were identified; 20 Cyanophyta, 4 Chlorophyta and 17 Chrysophyta ( Diatomeae ). Among them Lyngbya martensiana, Nos toe microscopicum, Phormidium ambiguum, Ph. foveolarum and Ph. papyraceum were most frequent. In the transitional area a total of 51 species [Cyanophyta 26, Chrysophyta (Diatomeae

) 18, Euglenophyta 1 and Chlorophyta 6] were recorded. Among them Calothrix braunii, Chroococcus minutus, Microcoleus sociatus, Nostoc commune, N. microscopicum, Phormidium angustissimum, Ph. ambiguum, Ph foveolarum, Ph. papyraceum, Diatoma sp., Epithemia sorex, Hantzschia amphyoxis and Navicula sp. were most frequent. On the upper region of the shore, which is seasonally characterized by Aster tripolium, 44 alga species were found. Their taxonomical proportion is as follows: 24 Cyanophyta, 14 Chrysophyta (Diatomeae

) and 6 Chlorophyta. Among them Chroococcus pallidus, Lyngbya martensiana, Phormidium corium and Gongrosira trentepohliopsis were common (Table 2). The floristical changes occurring on the border of ponds and shore ecosystems may be examined, on the basis of data shown in Table 2. ODUM (1959) pointed out that temporary ponds are especially interesting and support a unique community, moreover, such ponds have a relatively large littoral zone and it is a favourable place for certain species because intraspecific competition is much reduced here. Let us consider the change of frequency of the species. There were identified 185 taxa from the ponds (Kiss 1975) and 68 taxa from their shore, and only twenty taxa were common in both. The strong reduction in the species number refers to the fact, that water environment is more favourable for the algae than the soil habitat. A great deal of genera (i.e. Euglena, Lepocinclis, Phacus, TracheloAnn. Hist.-nat. Mus. Nat. Hung., 72, 1980