Swedish National Nitrogen Budget – Forest and semi-natural vegetation
This report describes the flow of reactive nitrogen for forests and semi-natural vegetation in Sweden according to the methodology developed within the framework of the Task Force on Reactive Nitrogen (TFRN). Forest and semi-natural vegetation (FS) constitute one out of 8 pools for the Swedish National Nitrogen Budget. The FS pool is divided into the three compartments; forest, wetland and other land. Together they amount to 71% of the country area.
The data used has been collected from Swedish official statistics and reports and are representative for year 2015 whenever possible.
In total, the FS pool has inflows of reactive nitrogen of 175.8 kilotonnes (kt) and outflows of 188.6 kt. The largest inflow is from atmospheric deposition (99.3 kt) and the largest outflow is via leaching/runoff (67.4 kt). Forestry is a major industry in Sweden and the nitrogen flow from the forest due to harvest is the second largest outflow from the FS-pool (58.5 kt). Biological fixation of nitrogen is an important inflow for both forest (39.5 kt) and wetland (32.1 kt). Other land (which mostly consists of mountains) is of smaller quantitative importance and only has two flows: leaching/runoff and deposition (2.9 kt N and 2.9 kt N, respectively).