Comparison of carbon-stock changes, eddy-covariance carbon fluxes and model estimates in coastal Douglas-fir stands in British Columbia

Forest Ecosystems

Table 4 Environmental predictor variables used to determine stratification units at DF49, HDF88, and HDF00

			Selection
Coverage	Variable	Units	*DF49*	*HDF88*	*HDF00*
Forest-Inventory	Site Index¹	m	selected
Forest-Inventory	Top Height	m
Disturbance History (Trofymow et al. 2008)	1st Harvest	year
	2nd Harvest	year
	1st Fire	year
	2nd Fire	year
	Date Est. 1953	year
	Date Est. 2003	year
	1st Fertilization	year
	2nd Fertilization	year
	Fire Cause 1	nominal
	Fire Cause 2	nominal
Topography³	aspect	azimuth	selected	selected	selected
	Elevation	m asl			selected
	Slope	degrees	selected	selected	selected
	SCOSA²			selected	selected
	SSINA²			selected	selected
	TSRAI²		selected	selected	selected
1999 Orthophoto	Dominant Canopy Tree Density	stems ha⁻¹	selected	selected
(Gougeon 1995)	Dominant Canopy Tree Density	stems ha⁻¹	selected	selected
2004 Multispectral⁴	NDVI	NDVI	selected		selected
Forest-Inventory	Cover Species
(Trofymow et al. 2008)	Cover Species
(Trofymow et al. 2008)	Site Species
Soil Survey of Canada (Jungen 1985)	Most Common Soil Association
CFS and Forest Companies	Site Series		selected	selected
(Trofymow et al. 2008)	Site Series		selected	selected

¹Site Index: Tree height at 50 years age at breast height (1.3 m).
²Topographic Variables: SCOSA = Slope × cos (Aspect), SSINA = Slope × sin (Aspect); TSRAI (Topographic Solar Radiation Aspect Index) = (1-cos((π/180°)(Aspect-30°)))/2 (Roberts and Cooper 1989).
³Topography from 2004 LiDAR survey at DF49 and HDF00 (Coops et al. 2007). Topography from 1:50,000 National Topographic Series map at HDF88.
⁴Multispectral data from 2004 Quickbird survey at DF49 and HDF00. Multispectral data from 2004 Landsat scene at HDF88.