Climate response of carbon and water dynamics in a subtropical forest

The project will be carried out in subtropical forest at the Ailao Mt research station (24.32°N, 101.01°E), China. The primary forests are dominated by evergreen broadleaf tree species and shaped by monsoon inducing seasonal climate.

The research will combine tree-based and ecosystem-based measurements on carbon and water dynamics to quantify climate sensitivity of the subtropical forest. In terms of tree-based measurements, the commonly used methods are to measure changes in stem radius and water transport. We will assess intra-annual variation in stem growth and sap flow and the underlying climatic drivers. For ecosystem-based measurements, eddy covariance measurements have been widely applied, but this only captures net carbon and water fluxes, without partitioning into contributions from the components such as trees as the large contributor of forest carbon fixation and water cycles. By integrating above-mentioned measurements, we will then evaluate the role of these tree performance in forest carbon and water exchanges.

We have measured tree radial growth and sap flow for more than 10 species using dendrometer and thermal dissipation probes. Carbon and water fluxes have been measured with the open path eddy covariance system at flux tower above forest canopy. This project will improve understanding on climate sensitivity of subtropical forest under climate change.