An in vitro study was conducted to
investigate the impacts of microplastics on enzyme activities and soil
bacteria. The study included four different treatments of microplastics
including a control. Different levels of microplastics were applied to the soil
ranging from 0% to 5%, to assess the impacts of microplastics on soil enzymes
and subsequent soil bacteria. After 30 days of incubation, the soil samples
were collected and growth parameters of bacteria were assessed. Activities of β-glucosidase, urease and dehydrogenase
enzymes were also determined. Our results showed that the presence of
microplastics in the soil significantly reduced bacterial population together
with bacterial strains. The activities of β-glucosidase,
urease and dehydrogenase enzymes were reduced significantly to approximately
32%, 40% and 50% in microplastics treated soils respectively. Concentration of
microplastic has a role to play towards this
direction; the higher the concentration of microplastic the greater is the
impact on enzymes and soil bacteria. The present study on the microbial soil
health vis-à-vis microplastic
application indicates that the material can have negative effect on the soil
bacterial population of and thus ultimately may jeopardize soil health and crop
production.
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