Due to more and more increasing role of pollution surface waters in environment - particularly in populous regions - in this paper the problem of the influence of the town of Nakło city on purity of the Noteć river has been presented. Hydrochemical investigation of the Noteć river in the region of the community Nakło indicated II and III water quality classification. The town of Nakło discharges very much pollution into this river. In spite of recent certain improvement in comparison to 1993-1995 years the annual amount of pollution flowing from the town into the river is still too large and it is 3149 Mg of suspended matter, 266 Mg of nitrogen and 69 Mg of phosphorus.

In 2002 the circulation of nutrients and their balance was studied in a large, shallow, eutrophic Lake Gardno. It was determined that throughout a year 1516 Mg of total nitrogen and 155 Mg of total phosphorus reach the lake. Approximately 67% of nitrogen and 87% of phosphorus reaching the lake flows out of it, the rest remains in the lake. About 45% of the total loss of nitrogen results from denitrification, and about 53% from sedimentation. The greatest effect on the circulation of nutrients in Lake Gardno is exerted by the mixing of water caused by strong winds resulting in the upward movement of the surface layers of bottom sediments. This causes increased resuspension and sedimentation, which mask similar processes resulting from the outer load of nutrients and from autochtonie processes and products, which are one or two orders ofa magnitude smaller.

The aim of this study was to compare various methods of anti fungal activity determination in model experiments. For the investigations Bacillus coagulans (No. 6) isolate with the high anti fungal activity, isolated from lupine composts was used. Anti fungal activity of the examined isolate was estimated against five pathogenic species of fungi: Rhizoctonia so/ani, Bipolaris sorokiniana, Sclerotinia sclerotiorum, Trichothecium roseum and Fusarium oxysporum. Determination of fungal growth was carried out by three methods: ergosterol assessment, counting colony-forming units (CFU) and agar plate diffusion assay. Statistically significant Spearman's rank coefficients were recorded between ergosterol assessment and two other methods. On the basis of this data the assessment of ergosterol is the best way ofdetermination of antifungal activity and may be used as a reference procedure.