Ecological Archives E096-206-A2
Qiang Yu, Kevin Wilcox, Kimberly La Pierre, Alan K. Knapp, Xingguo Han, and Melinda D. Smith. 2015. Stoichiometric homeostasis predicts plant species dominance, temporal stability, and responses to global change. Ecology 96:2328–2335. http://dx.doi.org/10.1890/14-1897.1
Appendix B. Supplementary tables of statistical analyses.
Table B1. Log-linear regression model statistics and stoichiometric homeostasis coefficients for phosphorus (HP) and N:P (HN:P) for 11 tallgrass prairie vascular plant species. G = grass, S = sedge and F = forb (all other herbaceous species).
Species |
Type |
|
HP |
R² |
p value |
|
HN:P |
R² |
p value |
Andropogon gerardii |
G |
|
4.68 |
0.42 |
<0.001 |
|
5.01 |
0.49 |
<0.001 |
Schizachyrium scoparium |
G |
|
3.81 |
0.72 |
<0.001 |
|
4.37 |
0.76 |
<0.001 |
Aster ericoides |
F |
|
3.12 |
0.73 |
<0.001 |
|
3.55 |
0.82 |
<0.001 |
Sorghastrum nutans |
G |
|
3.56 |
0.57 |
<0.001 |
|
4.42 |
0.48 |
<0.001 |
Salvia azurea |
F |
|
9.60 |
0.29 |
=0.003 |
|
7.48 |
0.51 |
<0.001 |
Solidago missouriensis |
F |
|
5.08 |
0.66 |
<0.001 |
|
5.09 |
0.68 |
<0.001 |
Dichanthelium oligosanthes |
G |
|
3.04 |
0.70 |
<0.001 |
|
3.21 |
0.81 |
<0.001 |
Bouteloua curtipendula |
G |
|
3.55 |
0.68 |
<0.001 |
|
3.39 |
0.84 |
<0.001 |
Ambrosia psilostachya |
F |
|
6.77 |
0.58 |
<0.001 |
|
5.21 |
0.61 |
<0.001 |
Solidago Canadensis |
F |
|
3.81 |
0.32 |
=0.001 |
|
- |
- |
=0.872 |
Carex meadii |
S |
|
4.53 |
0.62 |
<0.001 |
|
4.57 |
0.71 |
<0.001 |
Table B2. Regression results comparing species’ homeostasis coefficients (H) for nitrogen (HN), for phosphorus (HP) and for N:P (HN:P) with their dominance and stability values.
Dependent variable |
H |
Intercept |
Slope |
P |
Species Dominance |
HN |
0.018 |
2.12 |
<0.01 |
Ln (Dom) ~ H |
HP |
4.18 |
-0.17 |
0.44 |
HN:P |
0.68 |
1.01 |
0.50 |
|
Species Dominance |
HN |
-20.52 |
3.85 |
<0.01 |
Dom ~ H |
HP |
6.174 |
-0.405 |
0.73 |
|
HN:P |
3.752 |
0.189 |
0.93 |
Species Stability |
HN |
-1.93 |
0.51 |
<0.01 |
Stab ~ H |
HP |
1.60 |
-0.077 |
0.61 |
|
HN:P |
1.28 |
0.007 |
0.48 |
Table B3. Effects of nitrogen additions on species dominance. P values are based on repeated measures ANOVA. G = grass, S = sedge and F = forb.
Species |
Type |
HN |
2003–2006 |
|
2007–2012 |
||||
Dominance (%) |
Dominance (%) |
P values |
|
Dominance (%) |
Dominance (%) |
P values |
|||
Andropogon gerardii |
G |
9.76 |
25.0±4.3 |
25.9±4.4 |
0.830 |
|
29.3±2.6 |
24.5±3.5 |
0.209 |
Schizachyrium scoparium |
G |
8.41 |
32.3±2.5 |
20.9±2.7 |
0.009 |
|
26.5±4.3 |
4.7±1.1 |
<0.001 |
Aster ericoides |
F |
6.81 |
5.1±0.6 |
8.4±3.1 |
0.036 |
|
6±0.6 |
8.7±0.9 |
0.113 |
Sorghastrum nutans |
G |
6.75 |
12.8±0.8 |
18.1±1.9 |
0.232 |
|
6.8±1.1 |
15.3±3.8 |
0.007 |
Salvia azurea |
F |
6.63 |
0.2±0.1 |
0±0 |
0.330 |
|
0.1±0.1 |
0±0 |
0.317 |
Solidago missouriensis |
F |
6.28 |
2.2±0.4 |
0.6±0.1 |
0.184 |
|
2.5±0.4 |
0.5±0.1 |
0.105 |
Dichanthelium oligosanthes |
G |
5.53 |
3.2±0.3 |
4.2±0.7 |
0.336 |
|
5.3±0.6 |
20.1±3.5 |
<0.001 |
Bouteloua curtipendula |
G |
5.49 |
3.2±0.8 |
4.4±0.9 |
0.071 |
|
4.1±0.5 |
7.3±1.4 |
0.111 |
Ambrosia psilostachya |
F |
5.34 |
0.8±0.1 |
3.3±1.5 |
0.129 |
|
0.5±0.3 |
4.8±2.1 |
<0.001 |
Carex meadii |
S |
4.45 |
4.3±0.8 |
4.3±1.4 |
0.933 |
|
4.4±0.7 |
5±0.8 |
0.641 |