Microbiome dynamics of soils covered by plastic and bioplastic mulches

In recent decades, the use of plastic mulch in agriculture has largely increased to meet the growing demand for food. Despite their potential benefits, it is still unknown the long-term impact of mulches on soil microbiome. In this study, we compared at a mesocosm level the effects of polyethylene (Plastic) and Mater-bi® (Bioplastic) mulches on the soil physico-chemical (i.e., pH, soil water content, Fourier transform infrared-attenuated total reflection-FTIR), microbiological, and biochemical (i.e., microbial respiration, enzymatic activities, abundances and composition of bacterial, fungal and microarthropod communities) properties after 6 and 12 months. The analysis of the microbiome revealed an increase in bacterial richness and diversity in the 12-month-treated bioplastic soils. Members of Solirubrobacterales, Vicinamibacterales, Nitrososphaerales, Crenarchaeota, and Clostridiales were the most abundant following the bioplastic treatment. While the fungal and microarthropod communities varied over time, neither of them was affected by the type of mulching. Further longer-term research is needed to clarify the impact of bioplastic and plastic mulches on the soil microbiome, including microarthropods, and its dynamics over time.