[Simulation of CO2 exchange between forest canopy and atmosphere]

Area of Science:

• Biosphere-atmosphere exchange processes
• Forest ecology
• Environmental science

Context:

• Estimating carbon dioxide (CO2) source/sink distribution and vertical fluxes within forest canopies is crucial for understanding biosphere-atmosphere interactions.
• The study focuses on a broad-leaved Korean pine forest in the Changbai Mountains.

Purpose:

• To model the CO2 source/sink distribution and vertical flux within and above the forest canopy using inverse Lagrangian dispersion analysis.
• To validate the model's predictions against eddy covariance CO2 flux measurements.

Summary:

• The model, based on Raupach's localized near field theory, accurately predicted CO2 sources from soil-plant respiration in deeper canopy layers and CO2 sinks from foliage assimilation in upper layers.
• Canopy foliage acted as a CO2 source in the morning and a sink in the afternoon, while soil remained a consistent CO2 source.
• Simulation results showed an 89% average precision compared to eddy covariance measurements, with predicted CO2 exchange being 15% higher but showing identical temporal trends.

Impact:

• The findings enhance the understanding of CO2 dynamics in forest ecosystems and their role in the global carbon cycle.
• The study highlights the significant influence of atmospheric stability on forest-atmosphere CO2 exchange.
• Accurate modeling of CO2 fluxes is vital for climate change research and forest management strategies.