This PDF file includes:

• fig. S1. Sketch of sampling design, showing five transects distributed across a typical alpine forest grassland transition.
• fig. S2. Relationship between tree age and size at the time of sampling (y = 0.06x + 10.08; r² = 0.41; P < 0.01).
• fig. S3. Normalized tree ring widths and basal area increments plotted over time using individual measurements of all rings formed when trees reached two fixed diameters (10 to 11 and 30 to 31 cm).
• fig. S4. Late to early wood growth indicating stable seasonal growth patterns in recent decades.
• fig. S5. Wood and atmospheric carbon isotope composition.
• fig. S6. Meteorological data and atmospheric CO₂.
• fig. S7. Relationship between tree age and wood carbon, oxygen, and nitrogen stable isotope ratios (green, isolated trees; blue, forest patches; red, forest border; black, forest interior).
• table S1. Summary of mixed-effect model examining changes in tree growth over time at different portions of the vegetation gradient.
• table S2. Summary of mixed-effect models relating environmental factors and isotopic proxies of physiological performance during the recent tree growth
  acceleration phase (since 1960).
• table S3. Pairwise correlations of untransformed variables performed using the entire data set.
• table S4. Linear basal area increment (BAI) trends used to estimate growth rates, summarized in Fig. 2 by habitat and time periods.
• table S5. Floristic composition and ecological characteristics of the dominant tree species.
• table S6. An information-theoretic approach to evaluate multiple mixed-effect models and derive predictions that best represent the documented changes in tree growth.
• table S7. Structure of mixed-effect models used in this study.

Download PDF