Contents lists available at ScienceDirect Marine Pollution Bulletin journal homepage: www.elsevier.com/locate/marpolbul Are Mediterranean Marine Protected Areas sheltered from plastic pollution? S. Liubartseva a,* , G. Coppini b , R. Lecci b a Fondazione CMCC — Centro Euro-Mediterraneo sui Cambiamenti Climatici, Bologna, Italy b Fondazione CMCC — Centro Euro-Mediterraneo sui Cambiamenti Climatici, Lecce, Italy ARTICLEINFO Keywords: 2D Lagrangian modeling Coastline plastic flux Inverse problem Ranking plastic sources Sea surface circulation ABSTRACT Comparisons of six selected Mediterranean MPAs were conducted to find similarities and site-specific differences in coastline fluxes and sources of plastic marine litter. Output from the recently developed 2D Lagrangian model for the Mediterranean was post-processed to study (1) the National Park of ses Salines d’Eivissa i Formentera, (2) Nature Reserve of Bouches de Bonifacio, (3) North-East Malta MPA, (4) Specially Protected Area of Porto Cesareo, (5) Community Importance Site of Torre Guaceto, and (6) Ethniko Thalassio Parko Alonnisou Voreion Sporadon. Model coastline fluxes of plastic ranged from 0.4 to3.6kg(kmday) −1 , which is relatively low com- pared to the average flux of 6.2±0.8kg(kmday) −1 calculated over the Mediterranean 2013–2017. Shipping was identified as a major source of plastic litter in all MPAs studied, contributing 55%–88% of total plastic. Site- specific rankings of the top 5 land-based plastic sources revealed that sea surface kinematics control plastic drift. 1. Introduction The Mediterranean network of Marine Protected Areas (MPAs) was created to safeguard marine areas from loss and destruction of habitats, resource exploitation, eutrophication, invasive marine species, climate change,pollution,anddumping(Colletal.,2010). Approximately 1231 MPAs are currently maintained in the Mediterranean Sea, covering ∼7.14% (179,798km −2 ) of the total sea surface. The goal is to cover 10% by 2020 (MedPAN, 2016). At present, the Mediterranean MPA network plays an important role in providing ecosystem services, mi- tigating impacts of environmental threats, and increasing the ecological and socioeconomic resilience of coastal communities. Plastic marine litter poses a growing threat to MPA resources due to debris ingestion, entanglement, bioaccumulation, and changes to the integrity and function of habitats (Thiel et al., 2018). The threat to marine biota is well recognized for many taxa, including birds, mam- mals, sea turtles, fish, and a range of invertebrates (Vegter et al., 2014). Plastic debris may transport absorbed toxins (Rochman, 2015), and spread harmful algal bloom species (Masó et al., 2007) and pathogens (Viršek et al., 2017). Accumulation of plastic in benthic sediments might alter the quality of seabed habitats (e.g., seagrasses and cor- alligenous biocoenoses) by imposing physiological and toxicological risks (Casoli et al., 2017). The problem is exacerbated further by the semi-enclosed nature of the Mediterranean Basin, densely populated coasts, passage of 30% of the world's maritime traffic, and tourism, which has recently demonstrated stable growth in Mediterranean Europe (UNEP/MAP, 2015). Land-based sources of plastic litter are primarily unprotected land- fills and dumps located near the coast, in addition to riverine systems, overflow of sewage systems, and extreme events (e.g., floods, storm surges, excessive rainfalls). Sea-based plastic litter can be discarded accidentally or deliberately from all types of ships (e.g., merchant vessels, ferries, cruise liners, commercial and recreational fishing vessels) and offshore installations. Despite the regulations included in the International Convention for the Prevention of Pollution from Ships (MARPOL 73/78), deliberate waste emission to the sea may occur, and it is almost impossible to monitor and regulate. The widespread use of plastic materials in the fishery and aquaculture sectors additionally contributes to marine litter due to abandoned, lost, or otherwise discarded fishing gear (Lusher et al., 2017). In the absence of systematic monitoring of plastic litter over all the Mediterranean MPAs, numerical modeling offers a holistic approach that can shed light on the potential impact of plastic pollution at basin and regional scales (Aliani and Molcard, 2003; Mansui et al., 2015; Liubartseva et al., 2016; Fossi et al., 2017; Politikos et al., 2017; Zambianchi et al., 2017; Liubartseva et al., 2018; Shchekinova and Kumkar, 2018). A wide variety of useful applications can be identified and implemented by superpositioning marine biodiversity and calcu- lated plastic distributions or their derivatives (Coll et al., 2012). Such methodologies were developed and applied successfully to marine https://doi.org/10.1016/j.marpolbul.2019.01.022 Received 6 November 2018; Received in revised form 10 January 2019; Accepted 10 January 2019 * Corresponding author. E-mail address: svitlana.liubartseva@cmcc.it (S. Liubartseva). Marine Pollution Bulletin 140 (2019) 579–587 0025-326X/ © 2019 Elsevier Ltd. 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