How Can Local Environmental Planning Affect Forest Soil Acidity? A Case Study in Stockholm, Sweden

The objective of this study is to assess how local planning can influence the acidity in the upper forest soil layer. Exceedance of soil acidity was determined by a steady-state mass balance model approach in relation to both present and future deposition. Future deposition scenarios were derived for Stockholm County based on transportation planning. Europe-wide scenarios were derived using the RAINS (Regional Air Pollution Information and Simulation) model. The deposition changes were assessed in relation to two different types of forest harvesting practices: whole-tree harvesting; and stem harvesting. The results demonstrate that local emission reductions combined with tree stem harvesting give the greatest remediation of soil acidity. This implies that forest soil acidity can be introduced as an indicator in local environmental planning.