Reporting of the harmful effects that plastic pollution has on marine ecosystems has grown in the past two decades, with almost 700 marine species recorded to ingest plastic. In an effort to identify hotspot areas for plastic accumulation, harmonized protocols have been introduced across regions to quantify how much plastic is in the marine environment; floating on the sea surface, suspended in the water column, and settling on the seafloor with size fractions ranging from nanoparticles to mega-debris. Advanced modelling techniques using regional and global hydrodynamic models coupled with empirical data for ground truthing have provided spatially explicit maps of plastic pollution for studied and remote areas in order to identify sinks and sources. Alarmingly high plastic densities in many regions worldwide have identified their effects on the trophic web, with studies ranging from zooplankton to ichthyofauna to cetaceans. Moreover, these studies have reported ingestion/entanglement of plastic debris to cause not only ecotoxicological effects triggering biomarker responses from plastic exposure but also the potential lethality due to physical harm. Considering the link between plastic pollution in the marine environment and its impacts on marine diversity, this session aims to highlight multidisciplinary approaches to understanding connectivity and transferability of plastic pollution and within marine ecosystems and its effects on species. We invite researchers who employ multifaceted methods investigating plastic pollution to submit their research to this session.
Lead Organizer: Montserrat Compa, Centro Nacional Instituto Español de Oceanografía, Centro Oceanográfico de Baleares, Consejo Superior de Investigaciones Científicas (IEO-CSIC) (montserratcompa@gmail.com)
Co-organizers:
Carme Alomar, Centro Nacional Instituto Español de Oceanografía, Centro Oceanográfico de Baleares, Consejo Superior de Investigaciones Científicas (IEO-CSIC) (carme.alomar@ieo.csic.es)
Salud Deudero, Centro Nacional Instituto Español de Oceanografía, Centro Oceanográfico de Baleares, Consejo Superior de Investigaciones Científicas (IEO-CSIC) (salud.deudero@ieo.csic.es)
Joaquín Tintoré, Balearic Islands Coastal Observing and Forecasting System (SOCIB) (jtintore@socib.es)
Presentations
10:30 AM
PLASTIC POLLUTION IN A WARMING WORLD: WHAT ARE THE RISKS FOR ENGINEER SPECIES? (4834)
Primary Presenter: Marine Uguen, Université de Lille (marine.uguen@hotmail.fr)
Plastic pollution and the growing climate crisis are fundamentally linked not only in their underlining societal and economic nature of the problem but also in their co-occurrence in the environment. Indeed, they both pose a threat to habitats worldwide and endanger ecological engineers with cascading effects on the community these key species support. Here, we presented a short literature review on the effect of Micropalstics (MP) and their associated leachates – contaminants released by MP - and aerial heat stress on marine mussels, important ecosystem engineers in marine benthic systems. We underline the discrepancies in research effort (e.g. species, life stage, polymers used), and highlight the scientific knowledge gap on the combined effect of the two stressors, i.e. MP leachates and heat stress. We further assessed the impact of MP leachates on the ability of the mussel Mytilus edulis to survive heat stress. In addition, we asked whether differences in pollutants between virgin MP and those stranded on the beach may impact differently such ability. Mussel survival rates decreased when concurrently exposed to MP leachates and heat stress than when exposed to a single stress, particularly when in seawater with beached MP leachates. Our results stress the importance of a more integrated approach to determine the overall risk that ecological engineers may experience under increasing anthropogenic pressure.
10:45 AM
ADDING CONTEXT TO THE IMPACTS OF MICROPLASTICS ON SEAFLOOR CARBON CONSUMPTION (5069)
Primary Presenter: Samantha Ladewig, University of Auckland (samanthamladewig@gmail.com)
The accumulation of plastic pollution in marine sediments are projected to surpass organic carbon loads in some places in the near future. Therefore, it is important to understand the effects on these blue carbon zones, especially amid the climate crisis. We used a carbon consumption assay to gauge the effects of increased plastic pollution to the seafloor. Assay plates were filled with carbon-based media with and without polyester microfibers. To incorporate habitat heterogeneity, plates were deployed at 10 plots, each reaching 15 cm in depth, across intertidal flats of the Waitemata Harbour of Auckland, New Zealand. Results showed that media consumption rates change spatially and are largely driven by organic matter content, mud content, or mean grain size. This highlights the dependency of carbon degradation on the ambient sedimentary environment. Importantly, sedimentary environmental drivers were different for media with and without microplastic. Our results indicate that microplastic polyester fibers break ecosystem relationships and alter carbon cycling dynamics. Most importantly, our results illustrate the essential role that habitat heterogeneity plays in seafloor carbon consumption and the complexity of real-world microplastic-ecosystem impacts. Our multidisciplinary approach adds context to ecosystem-level effects of plastic pollution on seafloor carbon consumption rates.
11:00 AM
BIOACCUMULATION AND BIOMAGNIFICATION OF MICROPLASTICS AT DIFFERENT INTERTIDAL TROPHIC LEVELS (5471)
Primary Presenter: Zulema Varela, University of Santiago de Compostela (zvarelario@gmail.com)
Microplastics (MPs) pollution in the marine environment is one of the most serious environmental concerns of recent years. Despite the serious problem it represents, there is still a lack of knowledge, and it is unclear whether MPs biomagnify in marine food webs in the same way as persistent organic pollutants or whether they may have the potential to biomagnify more in some food webs than in others depending on the type of organism or the geographical scale. Therefore, the aim of this study is to characterize the concentrations of MPs in different intertidal trophic levels of the Ría de Arousa and Vigo (Galicia, NW Spain) and to check if there is biomagnification of these pollutants. Samples of brown algae Fucus vesiculosus and Fucus ceranoides as primary producers, mussel Mytilus galloprovincialis as filter feeders and the gastropod Nucella lapillus as predators, all of them stored in an environmental specimen bank at the Universidade de Santiago de Compostela, were used. The results obtained showed the presence of MPs in all the species studied, mostly polyamide 6 fibers of different coloring, but not the existence of biomagnification between trophic levels. Moreover, no spatial pattern was observed depending on whether the different sampling points were located in more or less anthropized areas of the rias. However, further studies are needed to confirm these preliminary results, which will serve to assess the impact and risks of bioaccumulation and biomagnification of MPs in coastal marine food webs and inform plastic waste management.
11:15 AM
Global plastic waste generation and macroplastic transport to land, rivers, and oceans since 1990 (5616)
Primary Presenter: Charlotte Laufkotter, University of Bern (c.laufkoetter@gmail.com)
Mismanaged waste, and in particular terrestrial and marine plastic pollution, represent some of the most pressing environmental issues. Yet, on a global scale waste generation has only been quantified for the year 2015. Estimates of macroplastic flow into environment and oceans therefore only exist for the year 2015 and into the future. Additionally, estimates of riverine and terrestrial plastic emission into the ocean are highly uncertain and strongly surpass the observed amount of plastic in the ocean. Here we use machine learning to estimate country-specific waste collection from 1990-2019, showing an increase in globally collected waste from about 1.1 billion ton in 1990 to 1.9 billion tons in 2019. The amount of plastic in the waste stream has increased from about 100 mio tons in 1990 to 400 mio tons in 2019, albeit with substantial uncertainties. We then estimate that between 40 and 1300 mio tons of macroplastic have leaked into the environment cumulatively since 1990. We next use observed macroplastic pollution in rivers to constrain the plastic flow into the ocean. Preliminary results suggest that between 0.1 and 16 mio tons of plastic have likely been transported to the ocean cumulatively, with mid-point estimates of 0.95-3.7 mio tons. Overall, our results indicate that due to a lack of observational constraints, previous parameterizations of plastic transport over land have resulted in significant overestimates.
11:30 AM
MICROPLASTIC POLLUTION AND FEEDING REGIME INTERACTIVE EFFECTS ON REEF-BUILDING CORALS (5853)
Primary Presenter: Maria Lopez, Justus Liebig University (maria.a.lopez@allzool.bio.uni-giessen.de)
Microplastic (MP) pollution is a rapidly increasing stressors for corals and reef ecosystems. While MP exposure leads to increased photosynthetic efficiency of the coral-associated photosymbiont, its interaction with heterotrophic feeding, the second source of coral energy, is less well explored. To address this knowledge gap, we studied the responses of two reef-building coral species (Pocillopora verrucosa and Stylophora pistillata) ina six-week MP aquarium experiment with different feeding regimes: CF (twice-weekly feeding of the microplastic-free control group), MP + CF (400 ppl mix of MP types + control feeding), and MP + HF (400 ppl MP + high, daily feeding). To assess the interactive effects of MP and feeding regime, we measured coral growth, photosynthetic efficiency, and photosynthesis and respiration rates. Surprisingly, coral growth was similar under all feeding and microplastic treatments. However, high feeding modulated the effects of MP on the photosymbiont of Pocillopora verrucosa, with increased photosynthetic efficiency and respiration in the MP + CF treatment compared to the other treatments. In contrast, Stylophora pistillata was not affected by MP exposure alone, but when combined with high feeding photosynthetic efficiency decreased. This decrease could be explained by an increase in their heterotrophic activity. These findings highlight that the feeding regime has an effect on the corals response to MP. Thus, future studies should consider the interactive effects of MP pollution and food availability to better mimic the natural environment.
11:45 AM
Sargasso Sea Vibrio bacteria: underexplored pathovars in a perturbed habitat (7004)
Primary Presenter: Tracy Mincer, Florida Atlantic University (tmincer@fau.edu)
We fully sequenced the genomes of 16 Vibrio cultivars isolated from eel larvae, microplastic debris, the pelagic brown macroalga Sargassum, and seawater samples collected from the Caribbean and Sargasso Seas of the North Atlantic Ocean. Annotation and mapping of these 16 bacterial genome sequences to a microplastic-derived Vibrio metagenome-assembled genome created for this study showcased vertebrate pathogen genes closely-related to cholera and non-cholera pathovars. Phenotype testing of cultivars confirmed rapid biofilm formation, hemolytic, and lipophospholytic activities, consistent with pathogenic potential. Our study illustrates that open ocean vibrios represent a heretofore undescribed group of microbes, some representing potential new species, possessing an amalgam of pathogenic and low nutrient acquisition genes, reflecting their pelagic habitat and the substrates and hosts they colonize.
SS047 Multidisciplinary Approaches to Understanding Plastic Pollution in Marine Ecosystems and Its Effects on Marine Species
Description
Time: 10:30 AM
Date: 7/6/2023
Room: Sala Ibiza B