L. Forró szerk.: Miscellanea Zoologica Hungarica 13. 2000 (Budapest, 2000)

Szabó, A.: A contribution to the Ciliata (Protozoa) fauna of chernozem soils

MISCELLANEA ZOOLOGICA Tomus 13. 2000 HUNGARICA p. 11-19 A contribution to the Ciliata (Protozoa) fauna of chernozem soils by A. Szabó (Received April 6,1999) Abstract: Protozoological studies have been carried out in a high quality chernozem soil located in the centre of the Great Hungarian Plain. In the samples 45 Ciliata species have been recorded belonging to 36 genera. The majority of species found are cosmopolitan, with broad ecological tolerance spectrum and they are also known from small water bodies. The number of species and individuals is decreasing step by step parallel with the depth. The highest value of them was found in the 10-20 cm layers, there were no active Ciliata in the 80 cm one, while even cysts were not found in layers deeper than 100 cm. The majority of species found belong to classes Kinetofragminophora and Polyhymenophora with same proportion (46.7%/47.1/%). Within Kinetofragminophora Hymenostomata were predominant (almost 24%). Of Polyhymenophora 46.4% were Hypotrichida. The estimated biomass of Ciliata (based on the cultivated numbers of individuals) has been found to be 24 kg/ha in the 0-10 cm layer, while in the 10-20 cm one 42 kg/ha. Keywords: chernozem soils, Ciliata fauna, biomass, ecology Introduction The function and importance of the microfauna (Protozoa: Ciliata) of soils has several aspects. They contribute to the N-fixation of Azotobacter species, decomposition of cellulose (Varga 1934), the growth of juvenile plants (Gellért 1958, Nikoljuk 1956, 1963) and they also increase the crop capacity of fields. By the products of their metabolism and their biomass they influence bacteria populations and they can make away with pathogen bacteria as well (Varga 1934). Despite of their various and mostly useful activities the microfaunistical (Protozoa, Ciliata) research is falling into the background abroad too (Foissner 1998, see also its references), but in Hungary it is especially neglected. Unfortunately there is not much information available on the Ciliata fauna of the high quality chernozem soils of Hungary either (Horváth 1942-43, 1950, Biczók 1953, 1955, 1956, 1958). The cultivated soils (e.g. chernozem) are usually richer in Protozoa than other (forest, alkaline, sandy) soils (Fehér & Varga 1929, Nikoljuk 1963). The method of cultivation can disturb the balance of the microfauna (Bonnet 1964). There are diverse communities in soils rich in humous (Bamforth 1973, 1977). It is obvious that these organisms are the most active along the roots, in the so-called rhizosphere (Bamforth 1976, Biczók 1953, 1955 Buitkamp 1977a-b, Gellért 1958, Nikoljuk 1968, Varga 1958, Darbshire & Greaves 1967). In this study results of the research on the Ciliata fauna of chernozem soils developed in one of the best croplands of the Great Hungarian Plain (Hajdúszoboszló, Eastern Hungary) are given.