The effect of harvest intensity on long-term calcium dynamics in soil and soil solution at three coniferous sites in Sweden

•Long-term effects on calcium of biomass harvest intensity were studied on forest soils.•Focus was on soil water concentrations and soil mineral pools.•Whole-tree harvest lowered the calcium levels more than conventional harvest.•The effects were largest at the well-buffered site not sensitive to acidification.•At the acidic sites, the effects were lower than recovery from acid deposition. Removal of logging residues may lead to soil and surface water acidification by lowering the amount of buffering base cations. Long-term treatment differences in soil exchangeable calcium pools (down to 20cm) and soil solution calcium concentrations at 50cm soil depth were examined at three coniferous sites in Sweden following conventional and whole-tree harvesting in 1974–1976. Results from the statistical analysis (p