Matskási István (szerk.): A Magyar Természettudományi Múzeum évkönyve 83. (Budapest 1991)
Lakatos, Gy., Ács, É. ; Buchtijarova, L. N.: Study on reed-periphyton in Lake Velence
RESULTS AND DISCUSSION The structure of periphyton, its dry mass abiotic and biotic components have been studied by several authors (LAKATOS et al. 1982; PIECZYNSKA 1979; SLADECKOVA 1966). The different inorganic and organic categories were constructed on the basis of earlier results of the chemical structure of periphyton and so it was possible to separate the autotrophic and heterotrophic periphyton. These "non taxonomic parameters" can be used to study the changes in the state of water quality of water bodies. The dry mass of periphyton collected from green and old reed varied between the following end values (Table 1). Fig. 1. Map of Lake Velence. For abbreviations see in the text. Table 1. Dry mass of peryphyton collected from green and old reed green reed old reed periphyton d. m. periphyton d. m. reed sterm m" 2 reed sterm m 2 1978 min. 6.0 Fü 27.6 Fü max. 89.2 Ht 156.8 Ht mean 30.1 ±24 86.8 ±46 1988 min. 12.1 Ve 25.2 K max. 77.9 Ht 136.5 Na mean 29.9±19 59.0±34 The data in the above table reflect the change in the dry mass of periphyton collected in Fürdető, but the subsequent one gives more information about the trends of periphyton-dry mass: dry mass of periphyton increased: green reed: L, Ho, ö, K, Fii, old reed: Fü; it remained constant: green reed: Nt, Ht, old reed: Na, Nt, N, Ö; it decreased: green reed: V, Vt, Na, Ga, Fe, N, B, old reed: V, Vt, L, Ga, Ho, Fe, B, K, Ht. The dry mass of periphyton taken in the algal brown water areas increased while the same in the dark brown water areas decreased. The decrease is more conspicuous in the case of periphyton collected in Felső-tó and Hosszú-tisztás, in areas which belonged to the category of large mass periphyton. Based on the dry mass of periphyton collected from green reed in the study years, the subsequent categories can be established. The increased dry mass of periphyton (e.g. Fü, L) can be explained by the larger ash content, i. e. the higher ratio of inorganic components.
