Title : Impact of plastic pollution on agricultural soil: Analysing extracellular polymeric substances and morphological changes in microplastics with sludge amendments
Abstract:
Microplastics in agroecosystems can significantly impact soil properties and microbial ecology, including the composition and availability of extracellular polymeric substances (EPS). EPS serve as a protective barrier for cells, shielding them from harsh environmental conditions and generally composed of polysaccharides, proteins, nucleic acid, lipid. This study compares the total content of EPS in agricultural soil (AS) and sludge-amended agricultural soil (SAS) incubated with different types of microplastics polyethylene (PE), poly vinyl chloride (PVC) and polystyrene (PS) for 15, 30 and 45 days to determine the effects of microplastics (MPs) in EPS production. The EPS content in SAS samples were found to be higher in all the incubated plastics samples compared to AS samples. This experiment suggests that PE microplastics can impact on the EPS production on both AS and SAS samples. The total content of carbohydrate and protein were also estimated by using phenol sulphuric acid method and Bradfords method, respectively. Subsequently, the incubated MPs were extracted to examine their surface morphological changes after 45 days of incubation periods, which were characterized using different techniques. Where, PS and PVC exhibited varying degrees of aggregation and surface texture changes when exposed to AS and SAS, whereas PE showed increased clumping and surface complexity in both types of samples.
