Table 1.
Basic information, temperature sensitivity indexes of assimilation rate (GPP, Q 10sG) and respiration rate (RE, Q 10sR), and net ecosystem productivity (NEP, μmol · m−2 · yr−1) of different climate groups.
| Climate group | MAT (°C) | Sample size | Q 10s | Mean | Standard deviation | Confidence interval (95%) | ΔQ 10s | NEP0 | NEP trend |
|---|---|---|---|---|---|---|---|---|---|
| Boreal | 2.43 | 93 | Q 10sG | 1.81 | 0.08 | (1.66, 1.98) | >0 (<0.0001) | =0 (0.13) | sink |
| Q 10sR | 1.41 | 0.06 | (1.30, 1.53) | ||||||
| Temperate | 8.67 | 310 | Q 10sG | 1.66 | 0.04 | (1.58, 1.74) | >0 (<0.0001) | >0 (<0.0001) | sink |
| Q 10sR | 1.43 | 0.04 | (1.36, 1.52) |
MAT is the mean annual temperature. ΔQ 10s = Q 10sG − Q 10sR. NEP0 is the current net ecosystem productivity. Values in parentheses of the ΔQ 10s and NEP0 column are P results of the null hypothesis test: P < 0.05 indicates that ΔQ 10s or NEP0 is significantly different from zero. The NEP trends indicate that the ecosystem should be a CO2 sink or a CO2 source to the atmosphere with temperature rise.