The chemical composition of the bottom sediment, and more particularly the heavy metals content, reflects human developments and impacts on the catchment and reservoir's natural environment. The bottom sediments of the reservoir retained by the Irkutsk Dam have been analysed. The reservoir is mainly supplied by water from Lake Baikal. The following amounts of heavy metals have been found in the sediment samples analysed: cadmium - below detection threshold (<0.5 ppm), cobalt - from 16 ppm to 23 ppm, chromium - from 104 ppm to 243 ppm, copper - from 21 ppm to 35 ppm, mercury - below detection threshold (<1 ppm), molybdenum - below detection threshold (<2 ppm), nickel - from 44 ppm to 80 ppm, lead - from 13 ppm to 17 ppm and zinc - from 73 ppm to 98 ppm. Cobalt, chromium and nickel contents exceeded the natural geochemical background level. This may indicates anthropogenic impacts on the reservoir's geosystem.

The aim of this research was to determine the trophic state of mountain dam reservoirs, which are characterized by greater hydrological and ecological dynamics than lowland reservoirs. The trophic state of three dam reservoirs forming a cascade system was investigated. Trophic evaluation was carried out based on multiple criteria, i.e., (1) the content of chlorophyll a in the water, (2) planktonic algal biomass, (3) groups and species of algae, (4) the total phosphorus concentration in the water, and (5) the Integral Trophic State index (ITS). The analyzed parameters were characterized by high variability during the study period, which to a large extent may have resulted from the mountain environmental conditions. The greatest dynamics concerned parameters related to phytoplankton development. Unequivocal determinations of the trophic states of the reservoirs were difficult; however, it was found that in successive reservoirs of the cascade (from the highest to the lowest), a reduction in water fertility occurred.

The study aims at investigating the so-called precipitation gradient, i.e. changes in the amount of precipitation depending on the elevation above sea level in mountainous areas of southern Poland. The gradient value is specified in mm of precipitation per 100 m elevation difference. Experimental...

The research consisted in analyses of occurrence of elements regarded as toxic (Zn, Cu, Ni, Cr, As, Pb, Cd, Hg), whose presence in the environment is mainly associated with economic-industrial activities, in mountain soils. The research area of about 5 sq. km. included hilltops and south-western...