Floating macrolitter leaked from Europe into the ocean

Abstract

he input of solid waste from terrestrial sources to the world's oceans has become a major environmental threat, positioning marine litter and plastic pollution as priority issues in the international agenda [1][2][3][4] . If no effective measures are taken, the prospects for future growth in the production and use of plastics foresee an unsustainable increase in the amount of waste accumulated in terrestrial and aquatic ecosystems around the world 5-7 , with potential impacts on biodiversity and human health 8,9 . Jambeck et al. 10 provided a first approach to modelling mismanaged waste (MW), regarding items as waste if littered or inadequately disposed of on land. Considering the population within a 50-km distance buffer from the coast and assuming a range of conversion rates to marine debris of between 15 and 40% MW, the authors estimated a global annual input of 4.8-12.7 million tonnes (Mt) of plastic to the marine environment. This range of conversion rates of MW to marine debris (15-40%) was based on municipal water quality data gathered in the San Francisco Bay (California) watersheds. Field measurements of plastic input to the oceans are, however, essential for evaluating MW land-ocean transfer rates 6,11,12 , still leaving considerable room for improvement.Rivers act as conduits to the ocean, funnelling the waste dumped into the drainage basins and, as such, they contribute to better understanding the input of litter to the ocean from terrestrial sources. Lebreton et al. 11 and Schmidt et al. 12 estimated the export

Rivers as Plastic Reservoirs

“…On global (Jambeck et al, 2015;Borrelle et al, 2020;Meijer et al, 2021), regional (Bai et al, 2018;van Calcar and van Emmerik, 2019;González-Fernández et al, 2021), and local levels (van Emmerik et al, 2019a;Schöneich-Argent et al, 2020;Vriend et al, 2020), several assessment strategies have been developed to estimate the plastic mass flows from land into rivers, and finally into the ocean. In recent years, the focus on estimating plastic emissions has shifted more toward understanding what happens with plastic within river systems before it makes it into the ocean.…”

Towards Underwater Macroplastic Monitoring Using Echo Sounding

“…The Guadalete river is known as one of the most polluted rivers in Spain. In the river basin 390,542 inhabitants are located, the estimated mismanaged waste is 6,073 tonnes per year (González-Fernández et al, 2021). It has an average width of 100 m, the depth at the measuring location was approximately 6.3 m. The sensor was deployed from a pedestrian bridge (of 100 m wide) over the river.…”

Macroplastic Debris Transfer in Rivers: A Travel Distance Approach

“…Given that modelled estimates of plastic flux have been generated using some form of calibration based on field measurements, the quality of these estimates are directly affected by the quality of these field measurements. Field measurements, however, are scarce, not standardised, spatially and temporally variable and are biassed by the higher frequency of studies in North American and European rivers (González-Fernandez and Hanke, 2017;van Emmerik et al, 2018van Emmerik et al, , 2019aGonzález-Fernandez et al, 2021). Research is ongoing to improve field measurements of plastic concentration (e.g., van Emmerik et al, 2018).…”