Journal Article 7440-44-0 Carbon Soil radiocarbon Carbon Radioisotopes Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. Review big data assimilation bomb-radiocarbon climate change mitigation deep learning diffusion-advection-reaction inter‐model uncertainty microbial decomposition minirhizotron model parameterization model structure organic matter stabilization root age root longevity root turnover soil carbon sequestration soil organic carbon survival function transit time two-pool model