Response of soybean and maize roots and soil enzyme activities to biodegradable microplastics contaminated soil

Although biodegradable plastic film is a promising alternative product for reducing polyethylene plastic pollution in agricultural soils, the effects of its residues on plant growth and soil properties remain unclear. In this study, we conducted an experiment to investigate root properties and soil enzyme activities in Poly (butylene adipate-co-terephthalate) microplastics (PBAT-MPs) contaminated soil (0 % (CK), 0.1 %, 0.2 %, 0.5 % and 1 % of dry soil weight) with soybean (Glycine max (Linn.) Merr.) and maize (Zea mays L.). The results show that PBAT-MP accumulation in soil negatively affects root growth, and alter soil enzyme activities, which may then constrain C/N cycling and potential yields. For soybean, the total root length, total root surface area and root biomass decreased by 34 %− 58 %, 34 %− 54 % and 25 %− 40 % at the harvesting stage compared to CK, respectively. The negative effects of PBAT-MPs on maize roots were greater than on soybean roots. The total root length, root surface area and root biomass of maize decreased by 37 %− 71 %, 33 %− 71 % and 24 %− 64 % at the tasseling and harvesting stage, respectively (p