Ecological Archives A022-033-A5

Kevin M. Potter and Christopher W. Woodall. 2012. Trends over time in tree and seedling phylogenetic diversity indicate regional differences in forest biodiversity change. Ecological Applications 22:517–531

Appendix E (TABLE E1). A table showing measures of phylogenetic diversity (PD), and PD change over time, at three taxonomic scales for forest tree seedlings < 2.54 cm dbh on Forest Inventory and Analysis plots in the northern and southern zones.

  Northern seedlings Southern seedlings
N Mean PD
Time 2
Mean PD
Time 1
Mean PD
T2-T1
P N Mean PD
Time 2
Mean PD
Time 1
Mean PD
T2-T1
P
(a) Plant
divisions
Angiosperms 3,800 532.41 535.21 -2.80 0.085 2,224 785.91 743.85 42.06 < 0.001
Gymnosperms 2,528 392.98 405.37 -12.39 < 0.001 1,115 280.59 292.72 -12.12 0.054
(b)
Common
families
Betulaceae 1,635 244.45 264.74 -20.29 0.001 508 271.28 218.46 52.82 < 0.001
Juglandaceae 231 264.05 256.23 7.82 0.63 970 273.52 255.65 17.86 0.004
Pinaceae 2,495 367.32 380.20 -12.88 < 0.001 876 242.68 278.11 -35.42 < 0.001
Rosaceae 2,047 281.08 233.26 47.82 < 0.001 981 248.24 231.19 17.05 0.053
(c)
Common
genera
Acer 2,737 285.90 306.02 -20.13 < 0.001 1,403 286.29 273.50 12.79 0.004
Pinus 608 261.29 296.98 -35.68 < 0.001 859 238.05 275.50 -37.45 < 0.001
Quercus 1,214 248.53 281.99 -33.45 < 0.001 1,740 302.09 295.11 6.99 0.002

Notes: PD is measured in millions of years per plot. Significant measures of mean plot-level change over time, based on a Wilcoxon signed rank test, are in bold.


[Back to A022-033]