Hydrochemical flood flow of the Vistula -august 2001

Intense rain in the south em part of the Vistula 's watershed in Ju(v 2001 resulted in floods in many places and in flood water flows on the Vistula and its tributaries. The culmination of the flood reached the Gulf of Gdańsk in the night of 5th August 2001. In the period 4th to 6th August, 10 samples of water were taken, and d1e content of biogenic substances and of other components in these samples was determined. Basing on water flow measurements and on the content of the investigated components, the loads were calculated and compared with mean multi-annual loads for the pen·od 1984- 1998. It was found that the mean biogen load, related to water flow, was exceeded many times. Also the relationships between the analysed components, water flow and variability during the period of investigations were detennined. Obtained results show that there may be a very significant influence of biogens on the condition of the environment and on the dynamics of biocenotic processes of the Gulf of Gdańsk in the period before and after the propagation of flood waters of the Vistula.