Soil carbon (C) cycling is greatly influenced by microbial growth and death, which is why understanding growth and survival traits of soil microorganisms is crucial for describing life history frameworks with relevance to C fate. In this study, we utilized 16S rRNA amplicon gene sequencing calibrated with an internal standard to measure bacterial populations over time within soils. Our research focused on assessing bacterial growth, death, and CO2 mineralization within soil microcosms subjected to different land-use and resource addition scenarios. We hypothesized that variations in microbial population dynamics would drive differences in soil C flux. Overall, in situ growth rates and lag times of soil bacterial communities were substantially more variable and generally slower and longer than those observed in culture-based studies. We additionally found that individual population dynamics differed from aggregate community dynamics. Taxa could often be organized into distinct groups based on growth characteristics, and these groups generally responded independently of one another. Attributes of these groups were also compatible with those predicted by the CSR (competitor-scarcity-ruderal) life history framework, supporting the use of this model for bacteria. We also found relationships between in situ growth rates and C cycling, including a positive correlation between community growth rate (weighted by taxon abundance) and CO2 mineralization, showing the utility of such a measure in predicting C flux from soils. We also showed differences in community growth efficiencies over time and in soils with differing land-use history. Lastly, we found that abundance gains during growth were strongly positively correlated with abundance losses during death, showing a clear pathway of plant C being converted into microbial biomass and then ultimately into necromass, which is more likely to become stabilized in soils. Ultimately, this research enhances our understanding of the interactions between microorganisms and soil C, contributing to the development of life history frameworks for bacteria and terrestrial C models.