Reducing continuous synchrony is an inherent property of tree growth in forests

Abstract Forests play an important role in providing ecosystem services and regulating carbon balance. Modelers rely on the implicit assumption that, under the common climate drivers, trees have similar growth patterns over large spatial scale. Using ring-width sequences of 1046 juniper trees from Tibetan Plateau and 538 pine trees in the eastern China, we show that, although tree growth is influenced by climatic factors, individual trees often do not respond in a synchronous manner. After highly synchronous growth events, the number of trees exhibiting common growth change declined progressively and, notably, the patterns of decline exhibited the form of exponential function with parameter of base b ranging from 0.57-0.83 for juniper forests in Tibetan Plateau and from 0.56-0.72 for pine forests in eastern China. Our findings suggest that individual trees in forests tend to grow independently with respect to climate rather than synchronously, and that a relatively uniform pattern of growth de-synchronization is an inherent property of forest tree growth. We propose that this property is essential for trees collectively to have resilience and maintain forest stability, analogous to maintaining a diverse investment portfolio as a strategy to cope with unexpected risks. This new perspective on widespread non-synchronous radial tree growth sheds insight into fundamental ecological processes in forest resilience and can improve assessment and management of forest health risks under future climate change.