Table 2. Predictor variables for reference (forest survey plots) and target (raster) data.

Category	Variable	Source for reference data	Source for target data
Vegetation	Vegetation class	Forest surveys(NFI, NPRS, SNUF)	National Institute of Forest Science, Forest type map (1:5,000)
	Height class	〃	〃
	Diameter class	〃	〃
Climate	Maximum temperature	Overlay of plot location with MK-PRISM	Korea Meteorological Administration, MK-PRISM v.2.1
	Minimum temperature	〃	〃
	Precipitation	〃	〃
	Photosynthetic active radiation (PAR)	Overlay of plot location with Solar resource map	Korea Meteorological Administration, Solar resource map
Topographic	Elevation (DEM)	NASA Shuttle Radar Topography Mission (SRTM)	NASA Shuttle Radar Topography Mission (SRTM)
	Slope	Derived from DEM	Derived from DEM
	Aspect	〃	〃
Location	Latitude	Forest surveys(NFI, NPRS, SNUF)	Center of 100 m grid cell for raster files
	Longitude	〃	〃