Fig. 4.

Correlations between monthly air temperature (Ta) anomalies and a–c monthly gross ecosystem productivity (GEP), e–g ecosystem respiration (RE), and i–k net ecosystem productivity (NEP) anomalies in spring (AM), summer (JJAS) and autumn (ON) in the 80-, 45-, and 17-year-old stands. Significant linear regressions at p < 0.01 are shown as solid lines. Significant linear regressions at 0.01 < p < 0.05 are shown as dash lines. The slope of the linear relationship between daily Ta anomalies and daily GEP (d), RE (h), and NEP (l) in each month are shown when the regression was significant at p < 0.05