Table 2.
Relationships between site-level mean leaf traits on a mass basis from the sun or shade layer of the canopy and elevation.
| Trait | Sun layer | Shade layer | ||
|---|---|---|---|---|
| R2 | Equation | R2 | Equation | |
| Light capture and growth | ||||
| LMA | 0.87 (7.9)*** | 15.6 x Elevation + 92.1 | 0.78 (8.3)*** | 11.8 x Elevation + 79.6 |
| N | 0.68 (0.2)** | −0.2 x Elevation + 2.4 | 0.67 (0.2)** | −0.2 x Elevation + 2.5 |
| Chlorophyll ab | NS | NS | ||
| Carotenoids | NS | NS | ||
| NSC | 0.70 (3.5)** | 4.1 x Elevation + 42.4 | 0.76 (3.6)** | 4.7 x Elevation + 40.2 |
| δ13C | 0.95 (0.3)*** | 0.9 x Elevation + −31.3 | 0.88 (0.4)*** | 0.7 x Elevation + −32.5 |
| Structure and defense | ||||
| C | NS | NS | ||
| Lignin | NS | 0.51 (2.8)* | −2.2 x Elevation + 27.3 | |
| Cellulose | 0.55 (1.8)* | −1.5 x Elevation + 18.3 | 0.54 (2.2)* | −1.8 x Elevation + 19.8 |
| Phenols1 | 0.96 (7.0)*** | 27.8 x Elevation + 42.7 | 0.93 (7.8)*** | 25.1 x Elevation + 43.6 |
| Tannins1 | 0.94 (5.1)*** | 17.2 x Elevation + 11.9 | 0.92 (5.8)*** | 16.1 x Elevation + 12.7 |
| Macronutrients | ||||
| P | NS | NS | ||
| Ca | NS | NS | ||
| K1 | 0.69 (0.06)** | 0.07*elev2-0.24*elev+0.72 | 0.61 (0.08)** | 0.08*elev2-0.25elev+0.79 |
| Mg | NS | NS | ||
| Micronutrients | ||||
| B1 | 0.79 (3.25)** | 6.2*elev2-18.9*elev+28.5 | 0.84 (2.82)** | 6.4*elev2-19.6*elev+29.3 |
| Fe | NS | NS | ||
| Mn | 0.57 (295.1)* | 257.1 x Elevation + 41.7 | 0.56 (312.0)* | 265.3 x Elevation + 24.1 |
| Zn | NS | NS | ||
Asterisks indicate significant levels as *p < 0.001, **p < 0.01, and ***p < 0.05. 1 or NS (nonsignificant) sites ACJ-01 and TAM-05 excluded from regressions due to unusual soil properties interacting with these traits. Elev is elevation. See methods for details.
Correlation value (R2) is provided with root-mean-squared error (RMSE) in parentheses. The equations are reported relative to elevation in km. LMA is leaf mass per area. NSC are nonstructural carbohydrates.