UNEP (United Nations Environment Programme) defines marine litter as any persistent, manufactured solid material discarded, disposed of or abandoned in the marine and coastal environment. Marine litter is a global and cross-boundary issue; it is found in all seas and oceans, and accumulates on the surface, seafloor and seashore. The presence of marine litter causes numerous impacts on the environment, biota, local economy and public health. It is perceived as one of the main threats to the marine environment by the general public. Nevertheless, only 15% of litter entering the sea reaches the shore; whileanother 15% remains floating on the surface, and 70% sinks to the seabed. Most of the scientific literature on marine litter has focused on defining the concept, and its origin and abundance in different seas, as well as the development of reporting protocols and monitoring guidelines. The next step is to reduce its abundance, in order to achieve "good environmental status" as defined in Descriptor 10 of the European Marine Strategy Framework Directive (MSFD), which deals with marine litter. Adequate management by local authorities, prevention and public awareness programmes are a key part of this process.
The objective of the LIFE LEMA project was to define a management service for local authorities for tackling the problem of floating marine litter (FML) before it arrives at shore areas with difficult access, or it sinks. The service, to be initially implemented in two transnational regions in the south-east of the Bay of Biscay (Gipuzkoa and Pyrnes-Atlantiques) would include tools and management plans. The replicability of the service would be assessed for the areas of Marseille and Bilbao. Most previous initiatives on FML have focused on defining amounts, source and composition, but LIFE LEMA aimed to going a step further by proposing an integrated protocol. Specific aims included:
The LIFE LEMA project implemented the collection of floating marine litter (FML) using two fishing vessels and three cleaning vessels during summer campaigns from 2017 to 2019. The 2017 campaign served to set a baseline, while the following two campaigns were used to validate a series of smart tools to predict the presence of FML, optimise collection and monitor these activities at the local level, and demonstrate the projects marine litter management system. During these campaigns, 42.7 tonnes of litter (80 tonnes if wood is also considered) were collected.
The project beneficiaries developed and validated a series of tools. These included a software tool (LEMA tool) that combines predictive models with metocean and historical data to predict convergence areas of marine litter to optimise collection and monitoring activities; and a remote video monitoring system based on infrared cameras that detects and monitors floating litter at river mouths, providing information for the prediction and early detection of FML. The installation of floating barriers in river mouths was found to have limited efficiency for collecting litter, but is useful for gathering information - especially for characterising FML and investigating its origin. A better understanding of the presence and accumulation of marine litter at sea was gained as a result of the project.
The socio-economic study concluded that sea cleaning vessels were more efficient for collecting FML (cost of 4-8/kg FML), but that fishing vessels were also efficient depending on FML density, time of year and the experience of fishers. Efficiency of collection increased with FML density, making the LEMA detection tool of particular interest in low-density areas with high density hotspots. The benefits of removing FML for the fisheries, aquaculture, ports, shipping and tourism sectors was estimated at between 2/kg and 8/kg, showing that all the vessels used in the project could be effective in economic terms.
The project demonstrated an alternative activity for fishing vessels that could supplement fishing incomes. The collection of marine litter could be used to profitably diversify the activities of fishing vessels during quieter fishing periods. The "field version" of the projects computing tool, which can be fitted to fishing vessels, was proven to be useful for the organisation of collection routes, and for recording data onboard that can subsequently be analysed by local authorities.
LIFE LEMA addressed the challenge of promoting cross-border and transnational cooperation to combat marine litter (highlighted by the Marine Strategy Framework Directive - MSFD) by developing a local holistic strategy with an innovative multidisciplinary and integrated approach. Besides, the project contributed to the debate on the implementation of the MSFD, the European Maritime and Fisheries Fund, and territorial policies that deal with the issue of marine litter that derives from many sectors. The project is also relevant to the Port Reception Facilities Directive and policies concerning waste and the circular economy.
A management plan and a guidance handbook for the collection of floating marine litter were drafted and disseminated, enabling the system to be replicated by other public authorities. LIFE LEMA raised awareness, which is a powerful tool to prevent the release and subsequent presence of litter in the sea. The project reached more than 500 000 people thanks to different dissemination materials and events, contributions on social media, workshops and conferences.
Further information on the project can be found in the project's layman report and After-LIFE Communication Plan (see "Read more" section).