Artificial soil systems: A tool for investigating microbial life strategy effects on substrate mineralization

Abstract

Soil microbes play a critical role in carbon (C) cycling, however, the influence of microbial life strategies and their interactions on C mineralization remains poorly understood. This study aimed to investigate how r- and K-strategist bacteria influence glucose mineralization using an artificial soil system, focusing on Bacillus subtilis and Streptomyces cinnamoneus. Through a 14-day incubation experiment, we found that B. subtilis exhibited rapid and high respiration rates, while S. cinnamoneus showed slower, delayed respiration rates, supporting their respective r/K classification. In co-culture treatments, cumulative glucose mineralization converged with B. subtilis monoculture levels and positively correlated with its relative abundance. These findings demonstrate that artificial soil systems effectively reveal how microbial interactions drive C dynamics, offering a controlled approach to elucidate mechanisms underlying soil C cycling.