Macro-and/or microplastics as an emerging threat effect crop growth and soil health

Abstract

Pollution caused by macro- and microplastics has become a global concern that is ubiquitous throughout the environment. The reported impacts of macro-and/or microplastics in soil were mixed without uniform conclusions. Here, we quantitatively analyzed the effects of macro-and microplastics on crop growth and soil health using a global meta-analysis, based on 2,226 paired field/ laboratory measurements from 141 papers published in the literature. The results show that the unabated accumulation of macro-and/or microplastics negatively impacts crop growth and soil health. Overall, there were no significant effects on crop-soil properties of macroplastics between 30 and 240 kg/ha excluding soil water infiltration rate, but the crop-soil properties were negatively impacted with time and macroplastics over 240 kg/ha excluding soil olsen-potassium. There were no significant effect on crop-soil animal properties of microplastics between 0.01 and 100 mg/kg excluding weight, but the crop-soil animal properties impacts were negative with time and microplastics over 10,000 mg/kg excluding plant chlorophyll. Using a random forest model (RF) trained with crop/ animal and macro-and/or microplastics factors, we found that the response of crop growth and soil health to macro-and/or microplastics was related to plastic content, plastic type, plastic size and crop/ animal type variables. Altogether, our findings of macro-and microplastics impacts on crop growth and soil health are crucial to policy-making related to agricultural sustainable development under global change.