Researchers at the Chinese Academy of Sciences found that microplastics in soil stimulate bacterial denitrification, converting soil nitrates into nitrous oxide (N2O), a greenhouse gas roughly 300 times more potent than CO2. This process reduces soil fertility and may threaten crop yields and food security. A separate study found biochar removed 92.6% of microplastic particles in test samples, suggesting a possible mitigation approach that requires further evaluation.
Microplastics Harm Soil Fertility and Drive Release of Nitrous Oxide — a Greenhouse Gas ~300× More Potent Than CO₂
Researchers at the Chinese Academy of Sciences found that microplastics in soil stimulate bacterial denitrification, converting soil nitrates into nitrous oxide (N2O), a greenhouse gas roughly 300 times more potent than CO2. This process reduces soil fertility and may threaten crop yields and food security. A separate study found biochar removed 92.6% of microplastic particles in test samples, suggesting a possible mitigation approach that requires further evaluation.
12:24, 02.11.2025Environment
Microplastics linked to nutrient loss and increased nitrous oxide emissions
Researchers at the Institute of Urban Environment, Chinese Academy of Sciences, report that microplastic contamination impairs soil function and stimulates bacterial denitrification, converting soil nitrates into gaseous forms including nitrous oxide (N2O). The peer-reviewed study, published in Environmental Science & Technology, tested mixtures of common microplastics such as polyethylene terephthalate (PET) and polyvinyl chloride (PVC) and found that higher microplastic concentrations amplified microbial denitrification activity in soil.
Denitrification can deplete essential soil nitrogen, reducing fertility and potentially lowering crop yields and food security. It also releases N2O, a potent greenhouse gas with roughly 300 times the global warming potential of CO2 over a 100-year timeframe, making these emissions important for both agriculture and climate change.
These findings indicate that microplastic pollution in agricultural and natural soils may have a twofold impact: undermining soil productivity while adding to greenhouse gas emissions that drive warming and extreme weather.
"Our findings contribute to a deeper understanding of the ecological effects of MP contamination on soil health and nutrient cycling. More importantly, they underscore the need to incorporate MP diversity into soil management strategies to mitigate nitrogen loss and safeguard soil ecosystem services," the authors wrote.
In related work, a separate research team reported that biochar — a stable, carbon-rich product made from plant biomass — removed 92.6% of microplastic particles in their laboratory samples. While promising, field-scale trials and long-term assessments are needed to confirm effectiveness and feasibility for agricultural application.
Practical responses include reducing single-use plastics and improving waste-management practices to limit further microplastic release, while supporting research into mitigation options (for example, biochar amendment and targeted soil management) to protect soil health and limit additional greenhouse gas emissions.