J. Kevin Hiers, Joseph J. O'Brien, Rodney E. Will, and Robert J. Mitchell. 2007. Forest floor depth mediates understory vigor in xeric Pinus palustris ecosystems. Ecological Applications 17:806–814.
Appendix A (Table A1). List of variables, abbreviations, and measurement units used in analyses.
Variable
Abbreviation
Units
Understory Vigor
Richness
No. of sp. 400 m-2
Bluestem1
stems m-2
Bunchgrass2
bunches m-2
Legumes3
stems m-2
Soil Surface
Litter depth (Oi)
Litter
cm
Duff depth (Oa and Oe)
Duff
cm
Litter + Duff
O Horizon
cm
Canopy cover
Openness
% open sky
Evergreen oaks
Midstory4 basal area
EOMBA
m2 ha-1
Overstory5basal area
EOOBA
m2 ha-1
Midstory density
EOMD
stems ha-1
Overstory DBH
EOODBH
stems ha-1
Deciduous oaks
Midstory4 basal area
DOMBA
m2 ha-1
Overstory5 basal area
DOOBA
m2 ha-1
Midstory density
DOMD
stems ha-1
Overstory DBH
DOODBH
stems ha-1
Longleaf pine
Overstory basal area
LPBA
m2 ha-1
Overstory DBH
LPDBH
cm
Fire frequency
Number of burns
NOB
burns 30 yr-1
Bluestem1 = all species of the genus Andropogon and Schizachyrium. Bunchgrass2 = all species with the bunchgrass growth form including Andropogon, Schizachyrium, Aristida, Sporobolus, Sorghastrum, Panicum. Legumes3 = all species in the family Fabaceae. Midstory4 = stems < 10 cm dbh. Overstory5 = stems > 10 cm dbh. dbh = stem diameter at 1.37 m height.