Table I.
Optimization results for the parameters of the model shown in Figure 3, as applied to the tracer time courses of shoot and root respiration (Fig. 2)
Model parameters include the size, half-life, and percentage contribution to respiration of pools Q1, Q2, and Q3. Together, the three pools accounted for 95% of shoot and root respiration. The remainder was supplied by sources that released no tracer within the 25-d-long labeling period (Fig. 2). The quality of the fits is expressed as the RMSE.
| Pool | Shoot | Root |
|---|---|---|
| size (mg C g−1 plant C) | ||
| Q1 | ≤0.2 | ≤0.2 |
| Q2 | 9.7 | 6.9 |
| Q3 | 70.3 | 45.0 |
| half-life (h) | ||
| Q1 | ≤0.1 | ≤0.2 |
| Q2 | 2.9 | 3.4 |
| Q3 | 33.0 | 33.2 |
| contribution (%) | ||
| Q1 | 16 | 13 |
| Q2 | 28 | 27 |
| Q3 | 51 | 55 |
| delay 1 (h) | ||
| – | 3.7 | 4.1 |
| delay 2 (h) | ||
| – | – | 0.8 |
| RMSE | ||
| – | 0.022 | 0.028 |