Biofilm assemblage and activity on plastic in urban streams at a continental scale

Plastics entering freshwater ecosystems are colonized by microbial biofilms, and microbe-plastic interactions can influence ecosystem processes and plastic fate. In this study, we assessed biofilm metabolism and community structure on plastic (foamed polystyrene and polyvinyl chloride) and natural substrates (unglazed ceramic tile) in urban streams spanning a nested geographic gradient in the continental United States. In addition to assessing biofilm metabolism by measuring biofilm biomass, respiration and chlorophyll-a levels, we used next generation amplicon sequencing of marker genes to characterize the bacterial, fungal and algal assemblages of the biofilms.