Map of the central-western Mediterranean Sea showing the location of all sampling stations and the distribution of un-corrected plastic densities expressed as grams of plastic per km2.
Size of the circles is proportional to measured concentration values on a logarithmic scale. Particles <700 μm and synthetic fibers were not included in density calculations. Data were plotted using GPS Visualizer (http://www.gpsvisualizer.com/) and post-edited in Adobe Illustrator CS5. Background map freely retrieved from DEMIS OpenGIS Web Map Server under open copyright licence (http://www.demis.nl/home/pages/wms/docs/OpenGISWMS.htm).