The Ecological, Economic and Social Dimensions of Marine Plastic Pollution and Marine Plastic Pollution Interventions

Marine plastic pollution (MPP) has emerged as one of the most pressing global environmental challenges of the anthropocene. There has been an upsurge in investment to mitigate MPP; however, interventions can be costly, inequitable, and ineffective in achieving their objectives. In my dissertation, I aim to research key considerations for creating cost-effective, equitable mitigation strategies for MPP and its impacts to marine biodiversity and coastal communities. In chapter one, I introduce the challenges plastic pollution poses. In chapter two, I use seascape ecology theory to present the concept of the plastic-scape and describe how seascape ecology principles, methods, and approaches to transdisciplinary science can inform research to mitigate MPP. In chapter three, I present a framework to help decision makers estimate the total cost of MPP interventions and partial costs accrued by stakeholder groups. I then apply this framework to two quantitative case studies and four comparative case studies to exemplify its use and highlight the ways spatial scale, temporal scale, and socio-economic conditions influence the intervention cost and cost distribution. In chapter four, I employ a trait-based approach to produce a framework for developing indices of species vulnerability to macroplastic pollution. Finally, in chapter five, I implement the framework developed in the previous chapter and present a multi-taxonomic, macroplastic vulnerability index for three marine taxa—mammals, birds, and turtles—to identify the marine species most vulnerable to macroplastic pollution in Hawai‘i. Overall, my dissertation shows how policy-driven, systemic research of MPP and its interventions can improve efforts to address MPP and its socio-economic and ecological consequences.