Abstract:Forests play a critical role in the global ecological balance. One of the major uncertainties in global climate change predictions is how the spatio-temporal dynamics of forests will be affected by global warming. Tree rings at different spatial and temporal scales can reflect the impacts of environmental change on tree growth, and can be critical for understanding the influence of climate change on forest ecosystems. Here, we investigated the spatio-temporal patterns of variation in climate-growth relationships of three common broadleaved tree species (Fraxinus mandshurica, Phellodendron amurense, and Juglans mandshurica) in a broadleaved Korean pine mixed forest across the north Zhangguangcai Mountains, northeast China. Tree-ring chronologies from three sample sites were established, transformed into principal component analysis (PCA), and analyzed through correlation analysis. With these analyses, climate factors limiting the radial growth were identified, as well as the detailed spatial radial growth-climate associations. The responses of the tree species at similar sites to climate factors differed significantly. Radial growth of J. mandshurica was limited by monthly total precipitation and minimum temperature, whereas P. amurense and F. mandshurica were mainly affected by monthly mean minimum temperature. This suggests that climate-growth relationships are affected by species-specific characteristics. With changes in temperature and precipitation patterns, the three hardwoods differed in their spatial growth response to climate factors. The radial growth of J. mandshurica in Fangzheng and Xidaquan was positively correlated with minimum June to August temperatures (P<0.05). In contrast, it was positively correlated in Fenghuangshan with minimum temperature and precipitation in May and June (P<0.05). The radial growth of P. amurense and F. mandshurica decreased from west to east with precipitation changes, since the correlation coefficients between tree-ring index and precipitation decreased from west to east. Temperatures in the north Zhangguangcai Mountains have increased since 1980, and the radial growth of the three hardwoods was consistent before 1980. Because climate factors affect growth differently, these boreal tree species showed inconsistent spatio-temporal responses to the recent warming, with J. mandshurica being probably the most sensitive species. Radial growth of P. amurense and F. mandshurica increased with rapid warming since 1980, whereas tree growth of J. mandshurica decreased after 1980. Therefore, J. mandshurica may be subjected to drought stress and a subsequent decline in radial growth in the north Zhangguangcai Mountains if global warming continues or exacerbates. In contrast, P. amurense and F. mandshurica may benefit from increased temperatures through enhanced radial growth. For future research, the spatio-temporal variation of growth-climate relationship of the three hardwoods could be explored further by investigating the tree ring anatomical and physiological responses.