A novel model for measuring carbon dioxide flux on soil surface using an accumulation chamber

Abstract

Soil surface carbon dioxide (CO2) fluxes hold significant implications for comprehending carbon cycling, global climate change, and ecosystem functioning. Accurate understanding and quantification of this flux are crucial for assessing the carbon dynamics of ecosystems and predicting the impacts of climate change. In this study, we analyzed the variation pattern of CO2 concentration within the accumulated chamber from Fick's law, accounting for diffusion gradient effect and considering leakage effect. We developed a simple model to measure the soil surface CO2 flux, and used the model to calculate the values of CO2 fluxes on a specific soil surface. Comparing the fitting results of the proposed nonlinear model with traditional linear models for the measurement data, we found that the linear model underestimated by at least 18%, even up to 45%. Overall, our research indicates that the proposed model exhibits significant advancement and higher predictive reliability, successfully evaluating soil surface CO2 flux.