Total concentrations in the mineral soil

Macronutrients are reported as oxides, while trace elements are reported as pure elements in ppm (mg/kg).

Geochemistry of the parent material

Differences in the mineralogy of soil types are caused by the material having been derived from different types of bedrock with varying mineralogical composition. This also means that the geochemical composition—the content of different chemical elements in the soil minerals—varies.

The geochemistry of the parent material constitutes one of the natural preconditions influencing soil development, vegetation, and forest ecosystems, and it both contributes to and limits forest productivity. It is also of great importance for the soil’s capacity to neutralise acidifying deposition.

Read more about macronutrients and trace elements

Via the links below, you can access maps of Sweden showing mean concentrations (in weight %) of each macronutrient or trace element in forest land mineral soil at a depth of 50 cm.

• Macronutrients
• Trace elements

Analysis of total geochemistry

The concentrations of macronutrients and trace elements presented in the maps represent total geochemistry at a depth of 50 cm. Total geochemistry is described as the mass fraction of the chemical elements present in the mineral soil. For major elements (macronutrients), the calculation of mass fractions (weight %) is normally based on oxides of the element. Trace elements, on the other hand, are reported as pure elements, typically in the unit ppm (parts per million), which corresponds to mg/kg.

Total geochemistry was determined as follows:

• The sample was sieved to remove the textural fraction >2 mm.
• Fifteen grams of the remaining soil were homogenised by grinding.
• The sample was ignited at 1000 °C.
• The sample was completely digested (fused) using a lithium borate melt.
• The melt was dissolved in HNO₃ (nitric acid).
• The solution was analysed using the ICP method.