L. Hably szerk.: Studia Botanica Hungarica 21. 1989 (Budapest, 1989)

Ács, Éva; Lakatos, Gyula: Preliminary algological study on biofouling in industrial water systems

MATERIAL AND METHODS Our 17 qualitative samples were taken in the Tisza Chemical Works (TVK), the Lenin Metallurgical Works (LKM), Hungarian Bearing Works (MGM) and Oil Refinery Works (TIFO) from their vertical plates of David-type cooling towers and cooling basins. Chemical, bacteriological, algological and zoological investigations of biofouling were carried out to reveal the circumstances of the fouling formation and its structural composition. This paper presents the results of the algological analysis. For the identification of algae, Amplival-type microscope was used. The diatoms were determined after H2O2 treatment from the constant-preparatum bedding in Pleurax. RESULTS 71 taxa were identified from samples of 17 sites (Table 1). It can be stated that some samples are very poor in species compared to the biofouling of natural water-bodies. The cooling towers provide special conditions for the algae. The species composition of the algal community is often influenced by a treatment of algicide or algistatic compounds. Only certain species of algae are able to endure these extreme circumstances, following significant disturbance from time to time. This may result in the fact that teratological algae are often present in the samples, as opposed to natural water-bodies, making the identification of species more difficult (Fig. 1). Scenedesmus quadricauda Pedias trum boryanum Nitzschia brevissima Fig. 1 Teratological algae in the biofouling of water cooling systems. (The basic form of species are also illustrated)