Net ecosystem exchange in Central Argentina: A 10-year analysis using the VPRM-WRF model

The Vegetation Photosynthesis and Respiration Model (VPRM) was driven by outputs from the Weather Research and Forecasting (WRF) model to estimate Net Ecosystem Exchange (NEE) in crop‐ and pasture‐dominated environments of central Argentina. Daily simulations covering 2010–2019 were performed to determine whether these regional ecosystems functioned as net CO₂ sinks or sources. The coupled WRF-VPRM adequately reproduced daily, monthly, and annual NEE variability, with reduced skill under low-light conditions and shortcomings in representing summer–winter double-cropping systems. A pronounced CO₂ uptake occurred during the summer season, followed by sustained emissions throughout the remainder of the year. Annual mean NEE shows a west–east gradient, with stronger CO₂ sinks along the Atlantic coast, near-neutral conditions across central Argentina and net CO₂ sources in the north and along the Andes. Modeled NEE was influenced by soil moisture and air temperature variability, resulting in significant differences between annual carbon budgets. Our results indicate that the study area acted as a net CO₂ sink, with an average uptake of 0.5 g CO₂ m⁻² d⁻¹ over the study period. These findings enhance our understanding of the carbon cycle in key agroecosystems of Southeastern South America (SESA) and provide a foundation for future research on the environmental factors influencing CO₂ exchanges within SESA biomes.