Lithostratigraphical, diatom and cladoceran evidence were used to demonstrate Holocene lake-level changes in two closed-basin lakes in western Finnish Lapland, north of the coniferous tree- line. The lake levels were significantly lower than present in early to mid-Holocene times, from about 8000 until about 4000BP, after which they rose to the present level. The changes are believed to be climatically controlled and regionally representative. The proposed mid-Holocene dryness in Lapland contrasts with the evidence from southern Sweden and Finland, where past lake levels indicate humid conditions during much of the mid-Holocene (Atlantic) time.

The eutrophicatedEnajarvi was studied by paleolimnological analyses and sediment mapping. The sedimentary record indicates that the lake nutrient balance had deteriorated due to lowering of the lake water level in the year 1928. From that event onwards Chironomus plumosus and Cyclotella astraea characterize the chironomid and diatom communities. The concentrations of sedimentary total and mobile phosphorus show that since then the internal load of phosphorus has controlled the nutrient cycle of the lake. The areal distribution of mobile phosphorus can be explained by dominant wind directions and wind resuspension of the sediment is the key factor in the nutrient cycle. Restoration of Enajarvi must be based on actions which stabilize the surface sediment and improve its natural phosphorusbinding capacity. They include the regulation of lake water to as high a level as possible and the removal of the majority of roach.

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Ten prehistoric Comb Ceramic vessels found near Kotka have been studied with the aid of AAS and diatom analysis. Correspondence between stylistic and decorative groupings show that the variation in the elements determined by AAS is apparently due to the coarse sand temper added to the clay during the actual manufacture of the vessels. The composition of the Pit and Comb Ware vessel differs considerably from the others, the ornamentation suggesting East Karelian provenience. The diatom flora in the clay material of the vessels corresponds to the stylistic classification. The raw material was apparently either glacial or fresh water clay, whose technical properties correspond to those of clay in modern tile production.