Changes in the quality of water in Brdowskie Lake in 1997-2006
Wydanie: 4 / 2010
Kategorie: Pollution and environment
Most lakes in Poland are shallow and vulnerable to degradation mostly due to lake morphology and landscape structure. Other factors, like discharged sewage, internal loading and human activities in the watershed are also important. During studies on Brdowskie Lake, water samples were taken twice a year (spring and summer season) from the surface layer and analyses of soluble reactive phosphates, total phosphorus, nitrates, conductivity, five-day biochemical oxygen demand, chlorophyll a, dry mass of seston and Secchi depth were undertaken. Brdowskie Lake is situated in Kujawskie Lakeland and its catchment basin covers about 155.3 km2. The littoral vegetation is dominated by reed bed with a minor presence of other taxa. The lake is very susceptible to degradation (morphology, agricultural lands, housing) and has several potential sources of pollution, e.g. Notec River, a nameless stream and summer houses. In general, water quality of the lake was better during the spring season, especially in terms of chlorophyll a and dry mass of seston concentrations. In 1997-2006, the level of conductivity was very changeable with the maximum values observed in 1999-2001. Significant correlations between some parameters in certain seasons of the year were found, e.g. between chlorophyll a and Secchi depth during spring and total phosphorus and phosphates in summer. The impact of water level fluctuations on water quality parameters, like total phosphorus and chlorophyll a was observed. According to the results, the quality water in Brdowskie Lake is improving. After a biological wastewater treatment plant in the catchment had opened, the rate of salts flowing into the lake with sewage was reduced.
Staniszewski R., Szoszkiewicz J. 2010. Changes in the quality of water in Brdowskie Lake in 1997 - 2006. J. Elem. 15(4): 705 - 712, DOI: jelem.2011.15.4.705-712