We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Freeze-thaw aging and microbial colonization converts microplastics into nitrogen cycling hotspots
AI summary Read the abstract
Researchers combined metagenomic analysis with microcosm experiments to show that freeze-thaw cycles physically crack and oxidize microplastic surfaces, transforming them into microhabitats that host specialized microbial communities with enhanced nitrite-reducing activity and elevated nitrous oxide emission potential — recasting microplastics as metabolically active hotspots under climate-warming conditions.
As global warming intensifies, the frequency of freeze-thaw events increases, significantly impacting microbial metabolism and biogeochemical cycling. However, the synergistic effects of freeze-thaw cycles (FTCs) and pervasive microplastics (MPs) on microbial community assembly and nitrogen cycling remain poorly understood. Here, we conducted a microcosm experiment integrating metagenomic and random forest model to elucidate the co-regulatory mechanisms of FTCs and MPs on plastisphere microbial communities and nitrogen metabolism. Results revealed that FTCs accelerated the environmental aging of MPs, inducing surface cracking and oxidation, thereby creating microenvironments favorable for microbial colonization. In the experimental microcosms, the combined effects of FTCs and presence of MPs increased microbial richness and diversity, promoted community differentiation between sediment and plastisphere, and increased microbial niche specialization. Functional analyses showed that FTCs induced a functional reconfiguration of the plastisphere nitrogen metabolism, with a selective enrichment of key enzyme genes, such as nitrite reductase, which may enhance nitrite redox activity and N₂O emission capacity. In the plastisphere, the contribution of Acinetobacter to nitrogen cycling increased, whereas Nitrospira declined, possibly due to oxygen limitation. Overall, our findings suggested that FTCs may facilitate transformation of MPs from inert pollutants into potentially metabolically active microhabitats, providing critical insights for assessing emerging pollutants and climate change.
More Papers Like This
Microplastic biofilms as potential hotspots for plastic biodegradation and nitrogen cycling: a metagenomic perspective
AI summary Read the abstract
Researchers used genetic analysis to study the microbial communities that form biofilms on different types of microplastics in an estuarine environment. They found that these plastic-associated communities contained genes for both plastic degradation and nitrogen cycling, suggesting the biofilms may play dual roles in the ecosystem. The study indicates that microplastic surfaces in waterways create unique microbial habitats that could influence both pollution breakdown and nutrient processing.
Marine plastisphere expands the ecological niche and evolutionary dynamics of nrfA-dependent nitrite ammonifying bacteria
AI summary Read the abstract
Scientists discovered that microplastics floating in the ocean host thriving communities of bacteria that process nitrogen in ways different from the surrounding seawater, including hundreds of previously unknown bacterial types. This matters because as plastic pollution accumulates in our oceans, it may be quietly reshaping the marine nitrogen cycle, a process essential to ocean ecosystem health and even greenhouse gas levels, adding another layer of environmental concern beyond the plastic itself.
Plastisphere-mediated nitrogen cycling and N2O emissions in inland waters: A systematic review
AI summary Read the abstract
Researchers synthesized evidence that microplastic biofilms in freshwater systems selectively enrich nitrifying and denitrifying bacteria while suppressing the gene responsible for converting nitrous oxide to nitrogen gas, creating conditions that amplify N₂O emissions — with biodegradable plastics posing an unexpectedly complex greenhouse gas risk.
Microplastics alter nitrous oxide production and pathways through affecting microbiome in estuarine sediments
AI summary Read the abstract
Researchers found that both petroleum-based and biodegradable microplastics increased nitrous oxide production in estuarine sediments, with biodegradable polylactic acid plastics showing greater effects by altering microbial nitrogen cycling pathways.
Hidden link between microplastic biofilms and aquatic nitrogen transformation: From regulator to diverse ecological effects
AI summary Read the abstract
This review pulls together existing research on how microplastics floating in lakes, rivers, and oceans become coated with slimy microbial communities (called biofilms) that can change how nitrogen pollution is processed in water. The concerning part: these microplastic biofilms can trigger the release of nitrous oxide, a potent greenhouse gas, while also potentially disrupting the natural nitrogen cycle that keeps aquatic ecosystems healthy. While this doesn't directly test effects on human health, it matters because it shows microplastics aren't just passive pollutants—they're actively reshaping water chemistry and ecosyst
Research digests by email
When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.