## 3 Results
### Analyzing Productivity Simulations Under Dry Conditions  
During the dry period DOY 214-227 in 2001, both VBall_WT and VBall_NS reproduced hourly dynamics of hummock and hollow shrub and moss GPP in agreement with hourly ecosystem GPP (Figures 9b and 11b). The increased simulated GPP from DOY 214 to DOY 215 in VBall_WT and VBall_NS was due to increased I\({}_{\text{SWR}}\) (Figure 18a) (Equations (S1.1.1.4) and (S1.1.2.2)). However, although the increase in I\({}_{\text{SWR}}\) continued to DOY 216, simulated GPP decreased due to the constraining effect of decreasing RH from DOY 215 to DOY 216 (Figure 18c), which decreased g\({}_{\text{g}}\) (Equation (S1.1.5.5)) and reduced T\({}_{\text{L}}\) (Equations (S1.1.3.1), (S1.4.4) and (S1.1.4.6)). With no pronounced difference in I\({}_{\text{SWR}}\) from DOY 217 to DOY 219 (Figure 18a), the simulated increase in GPP was caused by the combined effects of increased T\({}_{\text{air}}\) and RH (Figure 18b,c) increasing T\({}_{\text{L}}\) (Equations (S1.1.3.1), (S1.1.4.4) and (S1.1.4.6)), the effect of increased RH on increasing g\({}_{\text{g}}\) (Equation (S1.1.5.5)), and the effect of increased v\({}_{\text{w}}\) (Figure 18d) on increasing g\({}_{\text{b}}\) (Equations (S1.1.5.2) and (S1.1.5.3)). Simulated GPP remained similar during DOY 220 and  
Figure 16: Hourly simulated GPP of hummock shrubs (**a**), hummock moss (**b**), hollow shrubs (**c**), and hollow moss (**d**) by VBall_WT model run driven by the observed depth to water table, d\({}_{\text{WT}}\), applied to Mer Bleue bog during 2–15 August 2001. DOY means day of year. DOY 221, with a slight decrease on DOY 220, which was more apparent for VBall_NS (Figure 17) than for VBall_WT (Figure 16). This behavior aligned with the slightly lower RH and \(\mathbf{v}_{\mathrm{w}}\) on that day compared to their values during the adjacent days and matched the observed ecosystem GPP (Figures 9b and 11b). The decline in simulated GPP on DOY 222 was caused by a combined effect of meteorological and hydrological drivers. Lower \(\mathrm{I}_{\mathrm{SWR}}\), \(\mathrm{T}_{\mathrm{air}}\), RH, and \(\mathbf{v}_{\mathrm{w}}\) (Figure 18a-d) values than those in the previous days contributed to a more pronounced decline in simulated hummock and hollow shrub GPP on DOY 222, which remained low until the end of the period on DOY 227 (Figure 16a,c and Figure 17a,c). The effect of receding \(\mathrm{d}_{\mathrm{WT}}\) in VBall_WT (Figure 18e) and decreasing hummock and hollow near-surface \(\theta\) in VBall_NS (Figure 18f) during this period is of particular note. In VBall_WT, on average, \(\mathrm{d}_{\mathrm{WT}}\) was -59 cm below the hummock surface (respectively, \(\sim\)34 cm below the hollow surface), but gradually declined to \(\sim\)67 cm depth in hummocks (Figure 18e) (respectively, \(\sim\)42 cm depth in hollows) towards the end of the period. As  
Figure 17: Hourly simulated GPP of hummock shrubs (**a**), hummock moss (**b**), hollow shrubs (**c**), and hollow moss (**d**) by VBall_NS model run driven by the observed near-surface soil water contents, \(\theta\), applied to Mer Bleue bog during 2-15 August 2001. DOY means day of year. the simulated \(\overline{\theta}\) of the unsaturated peat above WT decreased with receding d\({}_{\text{WT}}\), the effect of vascular plants' adaptations to wetland soil f\({}_{\text{0A}}\) was initially around unity with \(\overline{\theta}\), varying close to \(\overline{\theta}_{\text{FC}}\) in Equation (11a,b), along with d\({}_{\text{WT}}\) fluctuations in peat above \(\sim\)60 cm in hummocks (respectively, \(\sim\)40 cm in hollows) during DOY 214-221. However, with deeper WT drawdown during DOY 222-227 (Figure 18e), f\({}_{\text{0A}}\) declined in Equation (11b), reflecting the decreasing needs of the plants to maintain their adaptations with improved soil aeration. The latter was reflected in the model by increasing the air availability in the soil via f\({}_{\text{0R}}\) in Equation (9) and f\({}_{\text{0R}}\) in Equation (10).