Upper Vistula River: response of aquatic communities to pollution and impoundment. II. Chemical composition of water and sediment

The following paper is a part of the complex studies and intends to provide the background for explaining spatial differentiation of plant and animal communities settled in the Upper Vistula River. The study has been conducted from 10.9 to 336.7 km of the river course. Physico-chemical parameters of water, and nutrient concentrations m surface sediment have been measured. This allowed to discern four zones according to the level of water pollution. The first one, with relatively clean waters, is located in the mountainous part of the Vistula River (to 10.9 km of the river course). The second one - moderately polluted - spreads to 66.2 km. The third zone, with heavily polluted waters, reaches to 248.2 km. The remaining part of the studied river course (to 336.7 km) can be considered as belonging to the fourth zone with considerably polluted waters.