The quality of Peat maps
The quality of the map has been evaluated by comparing the maps with field measurements at 2,883 locations throughout the country. As a measure of how well a map corresponds to reality, you can use an MCC value, where MCC stands for Matthew's Correlation Coefficient. Higher MCC value (closer to 1) indicates better, more accurate maps. The % of the peatlands found by the map is indicated by the recall value. The map of ≥ 50 cm peat depth maintains the highest quality, while there is a tendency for the map showing ≥ 30 cm peat depth to slightly overestimate the proportion of peatlands. Previous maps have instead underestimated the proportion of peatlands. For the continuous peat map indicating the thickness of the organic layer, the Root Mean Square Error (RMSE) is given.
- The property map is the most high-resolution topographical map, based on aerial image interpretation and shows larger peatlands of at least 2500 m2, however, many peatlands in woodland are missing from the map (recall= 50%, MCC = 0.61).
- The Quaternary deposits map is made based on aerial image interpretation and shows larger peatlands of at least 2500 m2, however, many peatlands in forest under canopy are missing from the map (recall= 70%, MCC = 0.65).
- The classified peat map ≥50 cm peat is based on laser measurements of the topography and modeling of the water's flow paths (recall= 80%, MCC = 0.73)
- Continuous peat map shows the thickness of the organic layer (6-88 cm), the uncertainty (RMSE) is ± 19 cm.