Table 2.
Bivariate correlations among nine leaf functional traits in G. max
| A mass | A area | Log LMA | Leaf N | Leaf C | Log leaf CN | Log leaf area | Log WUE | g s | |
|---|---|---|---|---|---|---|---|---|---|
| A mass | – | 35.5 (32.8, 38.5) | –1.7 (–1.8, –1.6) | 5.3 (4.9, 5.8) | 10.6 (9.7, 11.6) | –1.2 (–1.3, –1.1) | –0.4 (–0.5, –0.4) | –2.8 (–3.1, –2.6) | 1.8 (1.7, 2.0) |
| Aarea | 0.348 (<0.001) | – | 0.1 (0.04, 0.1) | 0.2 (0.1, 0.2) | 0.3 (0.3, 0.3) | 0.03 (–0.04, –0.03) | 14.7 (13.3, 16.2) | –0.1 (–0.1, –0.1) | 0.1 (0.1, 0.1) |
| Log LMA | 0.337 (<0.001) | 0.083 (<0.001) | – | –3.2 (–3.5, –2.9) | –6.3 (–6.9, –5.8) | 0.7 (0.6, 0.8) | 0.7 (0.7, 0.8) | 1.7 (1.5, 1.8) | 1.1 (1.0, 1.2) |
| Leaf N | 0.286 (<0.001) | 0.034 (<0.001) | 0.222 (<0.001) | – | 2.0 (1.9, 2.1) | –0.2 (–0.2, –0.2) | 2.2 (2.0, 2.4) | –0.5 (–0.6, –0.5) | –0.3 (–0.4, –0.3) |
| Leaf C | 0.200 (<0.001) | 0.004 (0.102) | 0.233 (<0.001) | 0.596 (<0.001) | – | –0.1 (–0.1, –0.1) | 4.4 (4.0, 4.8) | –0.3 (–0.3, –0.2) | –0.2 (–0.2, –0.2) |
| Log leaf C:N | 0.286 (<0.001) | 0.056 (<0.001) | 0.181 (<0.001) | 0.97 (<0.001) | 0.466 (<0.001) | – | –0.5 (–0.5, –0.4) | 2.4 (2.2, 2.7) | –1.6 (–1.7, –1.4) |
| Log leaf area | 0.0002 (0.767) | 0.019 (0.006) | 0.029 (0.001) | 0.076 (<0.001) | 0.166 (<0.001) | 0.051 (<0.001) | – | 1.2 (1.1, 1.3) | –0.8 (–0.8, –0.7) |
| Log WUE | 0.186 (<0.001) | 0.022 (0.002) | 0.171 (<0.001) | 0.0002 (0.403) | 0.001 (0.29) | 0.00003 (0.456) | 0.08 (<0.001) | – | –0.7 (–0.7, –0.6) |
| g s |
0.144
(<0.001) |
0.295 (<0.001) | 0.005 (0.079) | 0.001 (0.291) | 0.025 (0.001) | 0.0001 (0.435) | 0.003 (0.269) | 0.14 (<0.001) | – |
Values in the table above the diagonal correspond to the slope of the relationship (with 95 % confidence limits in parentheses), which are based on a standardized major axis (SMA) regression model. Values below the diagonal correspond to the r2 (and P-values in parentheses) associated with each SMA model, with significant relationships highlighted in bold.
Samples sizes for SMA models are n = 402 in all cases, except for correlations involving log water use efficiency (WUE) and stomatal conductance (gs) here n = 309.