Comparing satellite and ED flux tower data with simulated vegetation spectral reflectance in relation to ecosystem energy, water and carbon dynamics in Banksia woodland, Perth, Australia

Global carbon, water and energy fluxes are strongly regulated by the interactions between terrestrial ecosystems and the atmosphere. Precise quantification of these interactions is essential for assessing climate change impacts and enhancing the predictive capacity of biogeochemical and Earth system models. Despite their importance, long-term continuous measurements of carbon, water and energy fluxes remain limited for many ecosystems. This study analyses data from the ED Gingin flux station combined with satellite observations collected between 2020 and 2024, covering both winter and summer seasons, to examine seasonal dynamics and the carbon, water and energy balance of the Banksia woodland ecosystem in Perth, Australia. The results indicate that these woodlands function as net sinks for carbon, water and energy, as reflected by mean net ecosystem production (NEP). NEP was partitioned into gross primary production (GPP) and net ecosystem exchange (NEE) to distinguish photosynthetic carbon uptake from microbially driven carbon release. Variability in fluxes was primarily controlled by climatic factors, including temperature, vapour pressure deficit, rainfall and photosynthetically active radiation. Photosynthetic activity showed a strong relationship with NEE and ecosystem productivity was consistently higher during winter than summer. Overall, the findings demonstrate the effectiveness of integrating flux tower and satellite data to forecast ecosystem responses to climatic and anthropogenic disturbances.