Abstract
Ice and water samples were collected from Lake Haruna, Gumma Prefecture, in the winter, 1962. The vertical change of the concentration of several components (UV-absorbance, COD, Cl, and Ca+Mg) at the lake surface was investigated with the following results.
1. All the components are less concentrated in ice than in water which bordered it.
2. The degree of concentration from water to ice in regards to each component is expressed in the ratio (concentration in ice) / (concentration in water).
The ratio is is larger for Cl than for the other components. This fact means that in the course of freezing of lake water the desalting effect is less for Cl than for the others.
3. The ratio is found to be minimum in the deepest layer of ice contacting with lake water the ratios for E220, COD, Cl and Ca+Mg are 1/10, 1/10, 1/3 and 1/20 times those of lake water respectively.
