72
M. Rz˛ etała
Fig. 4.7 Anthropothermy in Rybnik water reservoir, i.e. caused by anthropopression increase in
water temperature against a background of normal thermal situation, i.e. thermal limnological
background—thermoisopleths expressed in °C ([18]; amended)
occurrence of the few meromictic stratification systems in water bodies in Poland
is the high water density caused exclusively by man-made factors (waste storage,
supply of high-density pollutants), which, when combined with the small area and
usually considerable depth of the water body in question and the presence of land
features which shield it result in the permanent stagnation of its waters [24].
4.5.2 Ice Phenomena
Ice phenomena are construed as the occurrence of ice in water irrespective of its
structure, form and duration [25]. The issue of icing of lakes and other water bodies
has been relatively rarely discussed in the Polish limnological literature. The most
frequently cited research results concerning limnic ice phenomena include data from
studies conducted in individual water bodies, less frequently regional studies or
analyses of ice phenomena in lakes carried out within a broader context. Of all the
ice phenomena observed in water bodies, the presence of a complete ice cover is the
one most readily noticed [26].
In water body, the vertical position of ice cover changes as a consequence of
the freezing of water resulting in ice thickness increasing from below and from
above and also as a result of ice melting, and ice cover evolution during the winter
season depends mainly on so-called external factors (mainly air temperature changes
and precipitation). The ice cover in water bodies changes its location during the
M. Rz˛ etała
Fig. 4.7 Anthropothermy in Rybnik water reservoir, i.e. caused by anthropopression increase in
water temperature against a background of normal thermal situation, i.e. thermal limnological
background—thermoisopleths expressed in °C ([18]; amended)
occurrence of the few meromictic stratification systems in water bodies in Poland
is the high water density caused exclusively by man-made factors (waste storage,
supply of high-density pollutants), which, when combined with the small area and
usually considerable depth of the water body in question and the presence of land
features which shield it result in the permanent stagnation of its waters [24].
4.5.2 Ice Phenomena
Ice phenomena are construed as the occurrence of ice in water irrespective of its
structure, form and duration [25]. The issue of icing of lakes and other water bodies
has been relatively rarely discussed in the Polish limnological literature. The most
frequently cited research results concerning limnic ice phenomena include data from
studies conducted in individual water bodies, less frequently regional studies or
analyses of ice phenomena in lakes carried out within a broader context. Of all the
ice phenomena observed in water bodies, the presence of a complete ice cover is the
one most readily noticed [26].
In water body, the vertical position of ice cover changes as a consequence of
the freezing of water resulting in ice thickness increasing from below and from
above and also as a result of ice melting, and ice cover evolution during the winter
season depends mainly on so-called external factors (mainly air temperature changes
and precipitation). The ice cover in water bodies changes its location during the