We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Microplastics affect organic nitrogen in sediment: The response of organic nitrogen mineralization to microbes and benthic animals
AI summary Read the abstract
Researchers investigated how different types of microplastics affect organic nitrogen cycling in sediments, measuring the responses of key nitrogen-transforming microorganisms. They found microplastics alter the composition of organic nitrogen and suppress certain nitrogen cycling processes.
Organic nitrogen is a crucial component of the nitrogen element, and its mineralization by sediment organisms may trigger river eutrophication. Microplastics (MPs), as emerging contaminants, influence nitrogen cycling in sediments. However, the response of organic nitrogen mineralization to sediment organisms (microbes and benthic animals) under MPs pollution remains unclear. This study used microcosm experiments and structural equation modeling to explore the effects of benthic animals and sediment microbes on organic nitrogen mineralization in the presence of polystyrene, polypropylene, and polylactic acid. Compared to the sediment without MPs, the addition of MPs caused a 17 % decrease in ammonium concentration. However, benthic animals enhanced the organic nitrogen mineralization, resulting in a 63 % increase in ammonium concentration. MPs pollution also significantly increase the nodes and edges in the microbial network and decrease the abundance of the organic nitrogen mineralization gene (UreC). In contrast, benthic animals reduce the microbial network complexity, shape keystone microbes (Lysobacter, Flavobacterium, Terrimonas, and Pontibacter), and enhanced UreC abundance. Structural equation modeling was conducted to confirm that benthic animals regulate keystone microbes, thereby promoting organic nitrogen mineralization. These findings indicate that the bioturbation by benthic animals may give arise to a sustained increase in ammonium concentrations in rivers polluted by MPs, therefore, exacerbate river eutrophication.
More Papers Like This
Effects of microplastics on inorganic nitrogen dynamics in surface water sediments under different disturbance intensities
AI summary Read the abstract
Laboratory experiments showed that microplastics in sediments alter nitrogen cycling in freshwater systems in ways that depend strongly on concentration: low levels boosted ammonium release, while high levels suppressed it and amplified nitrate consumption. These disruptions to the nitrogen cycle could affect water quality and aquatic productivity, especially in systems that are frequently disturbed by dredging or flooding.
Effects of microplastics on nitrogen and phosphorus cycles and microbial communities in sediments
AI summary Read the abstract
Researchers found that PVC, PLA, and polypropylene microplastics altered nitrogen and phosphorus cycling in freshwater sediments by shifting microbial community composition, with effects varying by polymer type and biodegradability.
Polyethylene microplastic and soil nitrogen dynamics: Unraveling the links between functional genes, microbial communities, and transformation processes
AI summary Read the abstract
Researchers conducted a six-month experiment to understand how polyethylene microplastics in soil affect nitrogen cycling, a process critical for soil fertility and plant nutrition. They found that while total nitrogen levels stayed stable, microplastics significantly altered the forms of nitrogen present by increasing ammonium and nitrate while decreasing dissolved organic nitrogen. The study suggests that microplastics reshape soil microbial communities and their nitrogen-processing activities, potentially disrupting the natural nutrient balance in agricultural soils.
Unveiling the impact of microplastics with distinct polymer types and concentrations on tidal sediment microbiome and nitrogen cycling
AI summary Read the abstract
Researchers tested how five different types of microplastics at varying concentrations affect microbial communities and nitrogen cycling in tidal sediments over 30 days. They found that microplastics generally reduced microbial diversity and enhanced nitrogen fixation, with biodegradable PLA plastic showing concentration-dependent effects. The study suggests that microplastic contamination in coastal sediments can disrupt important nutrient cycling processes driven by microorganisms.
Microplastics affect sedimentary microbial communities and nitrogen cycling
AI summary Read the abstract
A microcosm experiment showed that microplastics added to salt marsh sediment altered microbial community composition and disrupted nitrogen cycling, including reduced denitrification rates, suggesting that microplastic contamination could impair important biogeochemical functions.
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.