FUNCTIONAL DYNAMICS OF MICROBIAL-POPULATIONS IN WATERS CONTAMINATED WITH PHENOLIC LEACHATE

Spatial dynamics, abundance and the biodegradation potential of aquati c microbial communities were studied during the period from November 1 993 until September 1995 in the Kohtla-Jarve region of north-eastern E stonia. General trends in bacterial population density profiles indica ted that the microbial community and the heterotrophic, lipolytic, den itrifying bacteria and biodegradative bacteria (phenol, m-toluate, ben zoate, salicylate, camphor, naphthalene and heptane degrading bacteria ) were strongly inhibited in the highly polluted wafers with ail shale ash leachate effluent and the bacterial numbers increased as the poll ution load decreased. Microbial communities revealed significant adapt ation to phenolic compounds in the environment, particularly the pheno l and benzoate degraders. Distribution of phenol degraders showed rema rkable similarity with the heterotrophic, lipolytic and denitrifying b acterial distribution pattern. The biodegradation potential rose throu ghout the rivers Kohtla and Purtse revealing a high natural selfpurifc ation process. Correlation of environmental variables and bacterial gr oups was shown. Substrate utilization patterns as recorded with the BI OLOG GN system was used to assess metabolic dynamics of microbial comm unities and classifying the sampling sites according to their degradat ive potential.