| dc.description.abstract | Synthetic debris, more specifically plastic pollution, is a major concern to ocean ecosystems and wildlife globally. Five major accumulation zones (i.e. gyres) are identified to hold vast quantities of floating debris with concerns the Arctic is fast becoming a sixth. Despite growing research and political action, rates of production and emission continue to rise, with recent reports estimating around 10 million tonnes of plastic leaks into the marine environment every year (Boucher and Friot, 2017). This number forecast to increase in coming years (Geyer, Jambeck and Law, 2017). In Chapter 1 I present comparable assessment of sea-surface debris concentrations across three ocean basins. Using a single methodology, sea-surface trawl samples (n=44) were obtained from numerous locations within Arctic (ARC), Atlantic (ATL) and Pacific (PAC) Ocean basins, reporting a 100% incidence of synthetic material. Although particles appear ubiquitous, I report great variability in composition and type with concentrations varying greatly over spatial scale. With most identified particles offering no clear origin or form, except for pellets or microbeads, it is likely a vast proportion of sea-surface debris is of secondary origin, likely to have been floating at sea for some time. To the best of our knowledge, this is the first study of its kind to successfully utilise a single methodology to analyse and compare sea-surface concentrations of floating marine debris in numerous ocean basins, providing data in support of theories that the Arctic Ocean is fast becoming the world’s sixth major gyre. Chapter 2 sees me discuss and critically evaluate current attempts to combat the issue of marine plastic pollution. Encompassing both ‘hard’ (legally binding) and ‘soft’ (non-legally binding) policy, alongside preventative, mitigative, removal and behavioural strategies and solutions, developments, challenge and fragmented or flawed efforts are evaluated. Identifying ten focal point suggestions for the development of an effective global treaty, this Chapter sees me discuss avenues of research or policy - built on previous experience and success - necessary for the construction of a global agreement to combat marine plastic pollution. The findings presented in this thesis contribute to the understanding of marine plastic pollution as a trans-boundary planetary threat demanding immediate global action. They also highlight the need for collaborative action and research between global stakeholders, organisations, maritime industry and researchers stimulating coordinated attempts to mitigate its effect. Especially considering its support in theories suggesting concentrations of global plastic pollution in our oceans is increasing. Lastly it is hoped that both Chapter 1 and 2 provide useful criteria for methodologies (Chapter 1) and focal points (Chapter 2), to aid in the collection of baseline data, generate awareness and fundamentally aid in preventing vast quantities of plastic waste entering waterways across the globe. | en_GB |
