Table 2.
List of 3D‐CMCC‐CNR model parameters used in the sensitivity analysis, symbols, units, literature values, and their description (for references in values see Appendix S1: Table S2)
| Parameter | Symbols | Units | Fagus sylvatica | Pinus sylvestris | Picea abies | Process(es) | Description |
|---|---|---|---|---|---|---|---|
| K | k | ratio | 0.5 | 0.51 | 0.54 | L | extinction coefficient for absorption of PAR by canopy |
| ALBEDO | A | ratio | 0.15 | 0.12 | 0.06 | L | albedo |
| SLA_AVG0 | SLA0 | m2/kg DM | 40 | 14.7 | 7.52 | L | average specific leaf area (juvenile) |
| SLA_AVG1 | SLA1 | m2/kg DM | 20 | 4.49 | 3.9 | L | average specific leaf area (mature) |
| TSLA | TSLA | yr | 35 | 10 | 30 | L | age at which average SLA = (SLA_AVG0 + SLA_AVG1)/2 |
| SLA_RATIO | SLAsun:shade | ratio | 2.3 | 2.52 | 2 | L | ratio of shaded to sunlit projected SLA |
| LAI_RATIO | LAIall:proj | ratio | 2 | 2.6 | 2.6 | L | all‐sided to projected leaf area ratio |
| FRACB0 | PB0 | ratio | 0.2 | 0.3 | 0.6 | D | branch fraction (juvenile) |
| FRACB1 | PB1 | ratio | 0.125 | 0.1 | 0.1 | D | branch fraction (mature) |
| TBB | T BB | yr | 20 | 10 | 30 | D | age at which fracB = (FRACB0 + FRACB1)/2 |
| RHO0 | ρ0 | Mg DM/m3 | 0.64 | 0.4 | 0.425 | D | minimum basic wood density (juvenile) |
| RHO1 | ρ1 | Mg DM/m3 | 0.64 | 0.39 | 0.374 | D | maximum basic wood density (mature) |
| TRHO | T ρ | yr | 50 | 4 | 50 | D | age at which wood density = (RHO0 + RHO1)/2 |
| COEFFCOND | K D | Pa | 800 | 500 | 500 | C | define stomatal response to VPD |
| BLCOND | g BL | m/s | 0.01 | 0.01 | 0.009 | C | canopy boundary layer conductance |
| MAXCOND | g smax | m/s | 0.005 | 0.0025 | 0.002 | C | maximum stomatal conductance |
| CUTCOND | g cut | m/s | 6.00 × 10−5 | 7.50 × 10−5 | 6.00 × 10−5 | C | cuticular conductance |
| MAXAGE | agemax | yr | 400 | 300 | 400 | C + M | determines rate of “physiological decline” of forest |
| RAGE | r age | dimensionless | 0.95 | 0.95 | 0.95 | C + M | relative age to give fAGE = 0.5 |
| NAGE | n age | dimensionless | 10 | 4 | 4 | C + M | power of relative age in function for age |
| T_MIN | T min | °C | 0 | −2 | −4 | P + C | minimum temperature for assimilation/conductance |
| T_MAX | T max | °C | 40 | 35 | 35 | P + C | maximum temperature for assimilation/conductance |
| T_OPT | T opt | °C | 20 | 17.5 | 17.5 | P + C | optimum temperature for assimilation/conductance |
| T_START | T start | °C | 60 | P + C | thermic sum for starting growth | ||
| MINDAYLENGTH | h min | h/d | 12 | P + C | minimum day length for starting leaf fall | ||
| SWPOPEN | SWPopen | MPa | −0.34 | −0.5 | −0.5 | P + C | leaf water potential: start of reduction |
| SWPCLOSE | SWPclose | MPa | −2.2 | −2.2 | −2.5 | P + C | leaf water potential: complete reduction |
| OMEGA | ω | dimensionless | 0.8 | 0.8 | 0.8 | A | parameter controlling the sensitivity of allocation to changes in water and light availability |
| FRACS0 | εstem | ratio | 0.1 | 0.15 | 0.15 | A | parameter controlling allocation to stems/minimum ratio to C to stem |
| FRACR0 | εroot | ratio | 0.55 | 0.55 | 0.55 | A | parameter controlling allocation to roots/minimum ration to C to roots |
| FRACL0 | εleaves | ratio | 0.35 | 0.3 | 0.3 | A | parameter controlling allocation to leaves/minimum ration to C to leaves |
| FRUIT_PERC | εfruit | ratio | 0.2 | 0.2 | 0.1 | A | fraction of NPP allocated for reproduction during the prescribed seasonal period |
| FRUIT_LIFE_SPAN | Conelife | yr | 1 | 3 | 3 | M | life span for fruits |
| FINE_ROOT_LEAF | FRL | ratio | 1 | 0.622 | A | fine root C:leaf C(initialization) | |
| COARSE_ROOT_STEM | CRS | ratio | 0.36 | 0.29 | 0.19 | A | coarse root C:stem C (initialization) |
| LIVE_TOTAL_WOOD | LTC | ratio | 0.13 | 0.076 | 0.076 | A | live C:total wood C (initialization) |
| N_RUBISCO | NR | ratio | 0.162 | 0.055 | 0.055 | P | fraction of leaf N in Rubisco |
| CN_LEAVES | C:Nleaves | kg C/kg N | 27 | 36 | 42 | A + R | C:N of leaves |
| CN_FINE_ROOTS | C:Nfroot | kgC/kg N | 72 | 49 | 58 | A + R | C:N of fine roots |
| CN_LIVEWOOD | C:Nlive | kg C/kg N | 70 | 58 | 50 | A + R | C:N of live wood |
| BUD_BURST | BB | d | 20 | Ph | days of bud burst at the beginning of growing season (only for deciduous) | ||
| LEAF_FALL_FRAC_GROWING | LFF | dimensionless | 0.25 | Ph | proportion of the growing season of leaf fall | ||
| LEAF_FINEROOT_TURNOVER | ϒgreen | yr−1 | 1 | 0.25 | 0.195 | Ph | average annual leaf and fine root turnover |
| LIVE_WOOD_TURNOVER | ϒlive_wood | yr−1 | 0.7 | 0.7 | 0.7 | R | annual live wood turnover |
| DBHDCMAX | DBHDCmax | ratio | 0.5 | 0.45 | 0.4 | D | maximum DBH to crown diameter |
| DBHDCMIN | DBHDCmin | ratio | 0.14 | 0.14 | 0.14 | D | minimum DBH to crown diameter |
| SAP_A | SAPa | dimensionless | 0.778 | 0.974 | 0.851 | D + L | scaling coefficient in sapwood area vs. DBH relationship |
| SAP_B | SAPb | dimensionless | 1.917 | 1.7979 | 1.684 | D + L | scaling exponent in sapwood area vs. DBH relationship |
| SAP_LEAF | SAPleaf | m2/m2 | 5400 | 1480 | 2600 | D + L | leaf area to sapwood area |
| SAP_WRES | SAPres | g NSC/g DM | 0.11 | 0.05 | 0.05 | A + R | sapwood to reserve fraction |
| STEM_A | a S | dimensionless | 0.2837 | 0.127 | 0.127 | D | scaling coefficient in stem mass vs. DBH relationship |
| STEM_B | n S | dimensionless | 2.134 | 2.3 | 2.3 | D | scaling exponent in the stem mass vs. DBH relationship |
| CRA | CRA | m | 35 | 32 | 32 | D | Chapman‐Richards maximum tree height |
| CRB | CRB | dimensionless | 0.038 | 0.04 | 0.064 | D | Chapman‐Richards exponential decay parameter |
| CRC | CRC | dimensionless | 1.104 | 0.99 | 1.784 | D | Chapman‐Richards shape parameter |
The processes column summarizes the main physiological, functional, and structural process(es) that each parameter controls (L, light interception; D, plant structural trait; C, stomatal conductance; M, mortality; P, photosynthesis; A, partitioning and allocation; R, autotrophic respiration; Ph, phenology). PAR, photosynthetically available radiation; DM, dry mass; NSC, non‐structural tree C.