Same but different: A framework to design and compare riverbank macroplastic monitoring strategies.

Abstract:

Riverine plastic pollution negatively impacts aquatic ecosystems and the human livelihoods dependent on them. The development of effective mitigation policy measures requires monitoring data for a better understanding of the sources, transport mechanisms and sinks of riverine macroplastics. Monitoring of riverine macroplastic (>0.5 cm) is often done through the quantification of anthropogenic litter on riverbanks. However, currently available methods vary substantially, causing difficulties when comparing data collected using different methods.

We present a framework to support governments, practitioners, and scientist with the design of a monitoring strategy best fit for their research questions, and available resources. By synthesizing monitoring strategies currently in use, we have distilled four key elements to a monitoring strategy: (1) space, (2) time, (3) observers, and (4) item categorization. We provide an overview of the range of possibilities for each element, and the trade-offs that are associated with each option. We then show how to use this framework by offering possible strategies for two frequently asked research questions.

With this presentation we aim to provide a first step towards harmonization of riverbank plastic strategies, as well as to simplify the process for new monitoring efforts to be set up.

Preprint version of the manuscript: https://doi.org/10.31223/osf.io/jp6a2