Scientific publications

Chemical composition investigation of atmospheric precipitation in Petrozavodsk was carried out in December of 2008. Samples of snow were taken in different districts of Petrozavodsk: Drevljanka, 179 Kluchevaja, Sulazhgora, Kukkovka, Perevalka, Oktjabrsky avenue, K. Marksa str., Solomennoe. 9 samples were taken. These indicators were determined in snowmelt water: pH, alkalinity, K₊, Na₊, Ca₂₊, Mg₂₊, SO_42-, Cl_-, P_O, Р_min, Р_tot, NH₄₊, NO_2-, NO_3-, N_org, N_tot, Fe_tot, Mn, Al, Si, Zn, Cu, Pb, Cd. Median values were used at the analyses of the data. pH of snowmelt water in Petrozavodsk varied from 5.95 to 6.96, pH averaged was 6.31. The mean concentration of potassium was 0.19 mg/l that three times higher background value (0.06 mg/l). The concentration of Mg₂₊ in snow samples was rather low and varied from 0.01 to 0.64 mg/l. The concentration of sodium varied within the range of 0.25 to 1.71 mg/l. The concentration of chlorides changed from 0.69 to 2.64 mg/l, and was 1.60 mg/l on average. Concentration of calcium in samples of thawed snow water changed within 0.62–3.45 mg/l and has averaged 0.91 mg/l. The higher concentration of calcium was noted in the samples which have been taken in Drevlyanka district (1.52 mg/l), the October prospectus (1.34 mg/l) and Solomennoe (3.45 mg/l). Hydrocarbonates (Alk) are presence in all samples of snow. The sulphate concentration varied within the range of 1.38 to 6.77 mg/l. Sulphates were presented in all snow samples as a salt. Concentration of mineral and total phosphorus fluctuated within 1–43 µg/l and 1.2–68 µg/l accordingly. Nitrate nitrogen content changed within 0.21–1.38 mg N/l. Average concentration of organic nitrogen was 0.03 mg N/l. Concentration of ammonium changed from 0.33 to 0.96 mg N/l, and the amount of nitrites was 4 µg N/l on average. Average value of organic matter (1.68 mg O/l) did not exceed 2 mg O/l. Almost all samples of snow are polluted by oil products. Average concentration of Fetot (0.054 mg/l) was hardly above background (0.040 mg/l). Among heavy metals high concentration of Cu and Zn were noted.