Leachable Additives of Tire Particles Explain the Shift in Microbial Community Composition and Function in Coastal Sediments
Journal
Environmental Science and Technology
Journal Volume
56
Journal Issue
17
Pages
12257
Date Issued
2022-09-06
Author(s)
Abstract
Massive microplastics are deposited in the coastal zone. Tire particles (TPs) are an important microplastic source, but little is known about how TPs affect the microbial community composition and function in coastal sediments and the role leachable additives play in TP toxicity. Here, a microcosm experiment was performed using coastal sediments amended with different doses of TPs and with their leachable additives to investigate their effects on the sediment microbial community composition and function. Environmentally relevant concentrations of TPs can change the microbial community structure, decrease community diversity, and inhibit nutrient cycling processes, including carbon fixation and degradation, nitrification, denitrification, and sulfur cycling in sediments. Notably, the raw TP and leachate treatments showed consistent effects. A variety of additives were found in the pore water of sediment, and they could explain over 90% of the variations of the community structure. Further modeling revealed that leachable additives not only directly influenced community function but also indirectly affected community diversity and function by shifting the community structure. In addition, rare taxa could be crucial mediators of ecological functions of sediment microbial community. Combined, this study provides novel insights into the role of TPs' leachable additives in affecting sediment microbial community and function.
Subjects
additive | coastal sediments | ecological function | microplastics | pore water
Publisher
AMER CHEMICAL SOC
Type
journal article