Plastics in sea surface waters around the Antarctic Peninsula

Abstract

Although marine plastic pollution has been the focus of several studies, there are still many gaps in our understanding of the concentrations, characteristics and impacts of plastics in the oceans. This study aimed to quantify and characterize plastic debris in oceanic surface waters of the Antarctic Peninsula. Sampling was done through surface trawls, and mean debris concentration was estimated at 1,794 items.km^-2 with an average weight of 27.8 g.km^-2. No statistical difference was found between the amount of mesoplastics (46%) and microplastics (54%). We found hard and flexible fragments, spheres and lines, in nine colors, composed mostly of polyurethane, polyamide, and polyethylene. An oceanographic dispersal model showed that, for at least seven years, sampled plastics likely did not originate from latitudes lower than 58°S. Analysis of epiplastic community diversity revealed bacteria, microalgae, and invertebrate groups adhered to debris. Paint fragments were present at all sampling stations and were approximately 30 times more abundant than plastics. Although paint particles were not included in plastic concentration estimates, we highlight that they could have similar impacts as marine plastics. We call for urgent action to avoid and mitigate plastic and paint fragment inputs to the Southern Ocean.

Figure 1

Abundance of micro (purple) and mesoplastics (green) per sampling point in Antarctic waters. The map was created using the marmap package and graphics were inserted using the mapplots package and add.pie function on R 3.5.0 (https://www.r-project.org).

Figure 2

Concentrations and colors of plastics per sampling point off the Antarctic Peninsula.

Figure 3

Dispersal model of plastic particles sampled with a manta net in surface waters of twelve points off the Antarctic Peninsula. The model backtracked seven years of dispersal, using ocean surface current data from HYCOM and Stokes drift data from WaveWatchIII.

Figure 4

Fourier Transform Infrared (FTIR) spectra from (a) red, (b), green, and (c) yellow ocean paint fragments compared with those from the hull of the ship (red and green) and the manta net frame (yellow); (d) general appearance of paint pieces sampled around the Antarctic Peninsula.

Figure 5

Diatoms found in the Antarctic Plastisphere. (A) Chaetoceros sp.; (B) Melosira sp.; (C) Thalassiosira cf. antarctica Comber, (D) Thalassiosira sp.; (E) Eucampia antarctica (Castracane) Mangin (resting spore valve); (F) Navicula sp.; (G) Navicula cf. perminuta Grunow; (H) Pseudogomphonema cf. kamtschaticum (Grunow) Medlin; (I) Synedropsis sp.; (J) Extruded polystyrene foam piece covered with pennate diatoms of genus Synedropsis (overview with 30× magnification); and K: 500× magnification of the polystyrene foam for better visualization of microalgae.

Figure 6

Groups of organisms attached to plastics and paint fragments sampled at surface waters in Antarctica. Coccoid (A) and elongated bacterial (B) colonies, and marine invertebrate (C) adhered to marine plastics; coccoid (D) and elongated cells of bacteria (E) and Tetraparma-like microalgae (Chrysophyceae - Parmales) (F) adhered to paint fragments.

Figure 7

Sampling area of marine plastics in surface waters of twelve points off the Antarctic Peninsula (a), using a manta net (b). The map was created using the marmap package and getNOAA.bathy function on R 3.5.0 (https://www.r-project.org).