Table 2.
PLSR stability statistics for models built with a single camera (450–900 nm), and for models built with both cameras (450–1700 nm)
| Trait | 450–900 nm (Pika II) | 450–1700 nm (Pika II+Pika NIR) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Train R2 | CV R2 | RMSE (trait unit) | RMSE (%) | Bias (trait unit) | Train R2 | CV R2 | RMSE (trait unit) | RMSE (%) | Bias (trait unit) | Change in CV R2 (%) | Change in RMSE (%) | |
| V c,max (µmol m–2 s–1) | 0.91 | 0.79 | 38.7 | 11.2 | -0.49 | 0.96 | 0.74 | 45.3 | 13.1 | 1.64 | -5 | +1.9 |
| J 1800 (µmol m–2 s–1) | 0.88 | 0.59 | 35.3 | 11.5 | -0.39 | 0.95 | 0.52 | 41.1 | 13.4 | 3.42 | -7 | +1.9 |
| Chlorophyll (mg m–2) | 0.98 | 0.87 | 0.02 | 10 | 0.002 | 0.98 | 0.55 | 0.03 | 15 | –0.0008 | -32 | +5 |
| Chl a:b | 0.95 | 0.63 | 0.37 | 18.5 | 0.103 | 0.97 | 0.77 | 0.28 | 14 | 0.024 | +15 | –4.5 |
| C content (%) | 0.9 | 0.47 | 3.1 | 27.6 | 0.23 | 0.91 | 0.28 | 2.6 | 23.1 | 0.15 | -19 | +4.4 |
| N content (%) | 0.85 | 0.49 | 0.93 | 15.5 | -0.32 | 0.95 | 0.40 | 1 | 17 | –0.007 | -9 | +1.2 |
| P max (µmol m–2 s–1) | 0.82 | 0.54 | 7.77 | 1.06 | 0.12 | 0.91 | 0.50 | 8.52 | 11.6 | 0.75 | -4 | +1 |
| ϕ CO 2 (quanta/A µmol m–2 s–1) | 0.35 | 0.02 | 3.33 | 8325 | 0.014 | 0.5 | 0.01 | 3.79 | 9475 | -0.099 | -0.1 | +1150 |