The Study of Litter on Beaches
Plastic Waste and the Study of Litter on Beaches
Litter on the coastline is one of the most obvious signs of marine litter pollution. This study has an special relevance in Galicia, a community with nearly 1,500 km of coastline, of which nearly 300 km correspond to Galicia's 723 beaches. As litter found on the coastline can originate from numerous sources, measures to combat litter pollution need to target these different origin. Monitoring of litter pollution therefore also needs to be able to estimate the input from different sources in order to implement appropriate management and mitigation measures.
Surveys of litter stranded on the coastline are a primary tool for monitoring the load of litter in the marine environment and have been used world-wide to quantify and describe marine litter pollution. They can be used to measure the effectiveness of management or mitigation measures, identify the sources and activities leading to litter pollution and determine threats to marine biota and ecosystems.
The Convention for the Protection of the Marine Environment of the North-East Atlantic (OSPAR Convention) is the current legislative instrument regulating international cooperation on environmental protection in the North-East Atlantic. OSPAR Convention maintains a pilot project to assess quantities, composition and trends for marine litter found on beaches. The survey found that the most most frequently occurring marine litter items were made of non-degradable plastic or polystyrene.
Dr. Jesus Gago Piñeiro, from Instituto Español de Oceanografía (Spanish Institute of Oceanography), led a project in which the origin of the waste found on the beaches of Galicia was studied. His work provides some baseline value for beach litter on the Galician coast.
The results of this study found that the percentage of plastic waste among the litter found in the Galician coast is less than the average for the OSPAR area, but even so, plastics are the most abundant components. Similar results showing the ubiquitous presence of plastics items in the marine environment are found world-wide and indicate the predominance of plastics among marine litter.
As for the origin of these residues, the first place goes to fisheries, followed by tourism and sanitary. It is important to mention two points. First: Galicia has a major fishing tradition and a well-developed industry. The coastline of Galicia has 42 ports, most of them with large fishery activities (fishing, aquaculture and processing industries). In Galicia 4.6% of the active population is employed in the fisheries sector, a much higher percentage than in any other European Union country. It is therefore understandable that attention turned towards fisheries as the main source of waste.
Besides, it is noteworthy that in a region with a great deal of shipping traffic (around 45,000 merchant vessels per year), shipping was a minor contributor to litter. This fact destroys some prejudices that ascribe to marine traffic an outstanding role in the pollution of the seas.
It is also important to mention that in the OSPAR pilot project only beach litter items from the fishing sector showed a statistically significant increase on the sampled beaches.
As we already know, the plastic in the oceans is a threat to the ecosystem and to the humanity because it is a material that does not degrade, but is only broken into small particles that appear in the food chain and, therefore, in our own bodies.
Therefore, in order to evaluate the main sources, the measures to implement and their effectiveness for reducing beach litter, a regional analysis is extremely valuable. The local factors (rivers, ports, beachgoers, currents) influencing beach litter quantity and type need a specific analyses. Beach litter monitoring programmes based on regular surveys of stretches of beaches – as the study made by the Instituto Español de Oceoanografía – can be particularly valuable for defining background values and determining trends.
It should also be stressed that this information can be used as a basis for marine management decisions and policy development, to avoid pouring more plastic to the oceans.