Differential radial growth response of three coexisting dominant tree species to local and large-scale climate variability in a subtropical evergreen broad-leaved forest of China

Subtropical evergreen broad-leaved forests (EBF) face great pressure from global climate change. However, little consensus exists related to how coexisting trees in these forests will respond to climatic change. We used tree rings to establish climate-growth relationships of three coexisting dominant canopy tree species in an EBF located in the Gutianshan National Nature Reserve, Zhejiang Province, in eastern China. Our results emphasize highly species-specific radial growth responses to both local and large-scale climate variability. The radial growth of Pinus massoniana was enhanced by high minimum autumn and low winter temperatures as well as La Nia events. Positive growth responses in Castanopsis eyrei were linked to high minimum summer and spring temperatures. Low winter temperatures and summer sunshine also increased the growth of Schima superba. We modeled future tree-ring growth using two climate change scenarios. Under both an intermediate (Representative Concentration Pathway, RCP 4.5) and a high emission climate change scenario (RCP 8.5), we projected further growth acceleration in C. eyrei, but a reduced growth rate in S. superb. Growth of P. massoniana was not predicted to change under the RCP 4.5 scenario, but was predicted to increase significantly under the RCP 8.5 scenario. These results suggest that climate change will have repercussions for the competitive balance among these tree species in subtropical forests, and the diverging responses of individual tree species need to fully considered in any models of the effects of climate change on the EBF and in future management plans.