Summary
Undisturbed 1 m cores of profundal sediment and overlying water were collected from 4 morphometrically paired lakes, with differing degrees and kinds of cultural development, lumbering, and alkalinity. Vertical variations in sediment chemistry (K20, MgO, P, and S) correlate with the presence of European man (indicated by pollen) although the behavior of any one element is not similar for the 4 lakes studied.
Interstitial water chemistry profiles (diffusion controlled) indicate movement of K, Na, and SiO2 to or through the sediment-water interface. A pronounced “reactive” layer with higher concentrations of dissolved species is present at a depth of 1 to 5 cm and may act as a reservoir to supply nutrients to the overlying water. For all four lakes SiO2 values increase steadily downward attaining constant values ranging from 20 to 45 ppm.