The biogeography of the Plastisphere: implications for policy

Abstract

Microplastics (particles less than 5 mm) numerically dominate marine debris and occur from coastal waters to mid‐ocean gyres, where surface circulation concentrates them. Given the prevalence of plastic marine debris (PMD) and the rise in plastic production, the impacts of plastic on marine ecosystems will likely increase. Microscopic life (the “Plastisphere”) thrives on these tiny floating “islands” of debris and can be transported long distances. Using next‐generation DNA sequencing, we characterized bacterial communities from water and plastic samples from the North Pacific and North Atlantic subtropical gyres to determine whether the composition of different Plastisphere communities reflects their biogeographic origins. We found that these communities differed between ocean basins – and to a lesser extent between polymer types – and displayed latitudinal gradients in species richness. Our research reveals some of the impacts of microplastics on marine biodiversity, demonstrates that the effects and fate of PMD may vary considerably in different parts of the global ocean, and suggests that PMD mitigation will require regional management efforts.

Dangerous hitchhikers? Evidence for potentially pathogenic Vibrio spp. on microplastic particles

“…In contrast, V. vulnificus and V. cholerae are more abundant in the Baltic Sea (Böer et al, 2012), which is also reflected by our findings. As already shown elsewhere, free-living bacterial communities in general differ significantly from plastic-attached ones (Amaral-Zettler et al, 2015;De Tender et al, 2015;Oberbeckmann et al, 2014;Zettler et al, 2013), which holds also for microplastics investigated here. With respect to potentially pathogenic Vibrio spp., the species V. vulnificus and V. cholerae were only isolated from seawater samples but not identified on microplastics in the framework of our study.…”

“…Recently the microbial community on marine plastics was targeted in several studies, highlighting the composition and diversity of plastic-attached microorganisms (Carson et al, 2013;Zettler et al, 2013;Oberbeckmann et al, 2014;Reisser et al, 2014;Amaral-Zettler et al, 2015;De Tender et al, 2015). Within the microbial community on the "Plastisphere" (Zettler et al, 2013) sequences related to the genus Vibrio, a group of bacteria also containing serious pathogens, were found (De Tender et al, 2015;Zettler et al, 2013).…”

“…The diverse microbial communities on marine plastic debris differed clearly from the surrounding seawater (Zettler et al, 2013;Oberbeckmann et al, 2014;Amaral-Zettler et al, 2015;De Tender et al, 2015).…”

“…With respect to plastic microbial communities, Oberbeckmann et al (2014) found that the structure and taxonomic composition of these plastic associated communities vary with plastic type, but also with geographical location and season. Moreover, Amaral-Zettler et al (2015) found that "Plastisphere" communities of the Atlantic and Pacific Ocean clustered more by geography than by polymer type, with exception of polystyrene that showed significant differences to polyethylene and polypropylene.…”

“…Zettler et al (2013) showed that microbial communities on marine plastic debris differ consistently from the surrounding seawater communities and coined the term "Plastisphere" for this habitat. Furthermore, Amaral-Zettler et al (2015) reported that "Plastisphere" communities are genetically unique from the free marine water communities that envelop them and possess dominant taxa that are highly variable and diverse. Moreover, the composition of biofilm communities on plastic in marine habitats varies with season, geographical location and plastic substrate type (Oberbeckmann et al, 2014).…”