We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Laboratory tidal microcosm deciphers responses of sediment archaeal and bacterial communities to microplastic exposure
Summary
Researchers used a laboratory tidal simulation to study how different types of microplastics affect microbial communities in intertidal sediments over 30 days. They found that biodegradable plastics like polylactic acid significantly shifted both archaeal and bacterial community structures, particularly at higher concentrations. The study suggests that even so-called biodegradable plastics can substantially alter the microbial ecosystems in coastal sediment environments.
Microplastics (MPs) are 1-5 mm plastic particles that are serious global contaminants distributed throughout marine ecosystems. However, their impact on intertidal sediment microbial communities is poorly understood. In this study, we conducted a 30-day laboratory tidal microcosm experiment to investigate the effects of MPs on microbial communities. Specifically, we used the biodegradable polymers polylactic acid (PLA) and polybutylene succinate (PBS), as well as the conventional polymers polyethylene terephthalate (PET), polycarbonate (PC), and polyethylene (PE). Treatments with different concentrations (1-5%, w/w) of PLA- and PE-MPs were also included. We analyzed taxonomic variations in archaeal and bacterial communities using 16S rRNA high-throughput sequencing. PLA-MPs at concentrations of 1% (w/w) rapidly altered microbiome composition. Total organic carbon and nitrite nitrogen were the key physicochemical factors and urease was the major enzyme shaping MP-exposed sediment microbial communities. Stochastic processes predominated in microbial assembly and the addition of biodegradable MPs enhanced the contribution of ecological selections. The major keystone taxa of archaea and bacteria were Nitrososphaeria and Alphaproteobacteria, respectively. MPs exposure had less effect on archaeal functions while nitrogen cycling decreased in PLA-MPs treatments. These findings expanded the current understanding of the mechanism and pattern that MPs affect sediment microbial communities.
Sign in to start a discussion.
More Papers Like This
Unveiling the impact of microplastics with distinct polymer types and concentrations on tidal sediment microbiome and nitrogen cycling
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.
Diversity and functional genes of bacterial communities enriched from an estuarine sediment for degradation of polylactic acid microplastics
Researchers enriched bacterial communities from estuarine sediment to study their ability to break down polylactic acid microplastics, a common biodegradable plastic. After 60 days, the enriched cultures reduced the weight of the microplastics by 40 percent, with specific bacterial groups and degradation-related genes becoming more abundant. The study suggests that naturally occurring microbes in coastal sediments have meaningful potential to biodegrade certain types of plastic pollution.
Distinct microbial community structures formed on the biofilms of PLA and PP, influenced by physicochemical factors of sediment and polymer types in a 60-day indoor study
This 60-day lab study compared the microbial communities that grow on traditional polypropylene microplastics versus biodegradable polylactic acid (PLA) microplastics in sediment. Each plastic type attracted distinctly different bacterial communities, influenced by the plastic's properties and surrounding sediment chemistry. The findings suggest that even biodegradable plastic alternatives still alter microbial ecosystems in ways that could affect environmental and human health.
Microbial colonization and succession on polylactic acid microplastics (PLA MPs) in mangrove forests - the role of environmental conditions and plastic properties
Researchers incubated two types of biodegradable polylactic acid microplastics in mangrove ecosystems across four environmental settings for 90 days to study microbial colonization patterns. They found that microbial colonization progressed more rapidly in sediment than in water, and the type of plastic influenced which microbial communities developed. The study suggests that environmental conditions and plastic properties together shape how microorganisms interact with biodegradable plastics in natural settings.
Effects of microplastics on cold seep sediment prokaryotic communities
Researchers studied how polyethylene, polystyrene, and polypropylene microplastics affect microbial communities in cold seep sediments over a 120-day incubation period. The study found that microplastics significantly altered bacterial community structure in a type- and concentration-dependent manner, with some bacteria associated with plastic degradation increasing, while archaeal communities were less affected.