AGE-DEPTH RELATIONSHIPS IN SCANDINAVIAN SURFACE PEAT - A QUANTITATIVE-ANALYSIS

Surface peat becomes compacted by the combined effects of biological d ecomposition processes (mechanical breakdown and decay) and of the phy sical squeezing of peat into a smaller, more consolidated volume. We u se corresponding determinations of age and depth of 1041 surface peat cores from 14 Scandinavian boreal mires to demonstrate that, at least for the first 40 years after the peat is deposited, the compaction pro cess can be adequately described by assuming a constant compaction rat e. This result is used to calculate vertical surface peat growth rates that are corrected for compaction. Estimated compaction rates did not differ significantly between lawn and hummock habitats while signific ant differences that were not related to latitude were found among mir es. We interpret this as an indication that compaction rates depend on hydrology at the scale of mires. Vertical peat growth rates differed strongly among mires and between habitats within mires, indicating con siderable variation at several spatial scales.