Alumnos del Máster de Ecología Marina de la UIB defienden su tesis de máster

Alumnos del Máster de Ecología Marina de la UIB defienden su tesis de máster

El pasado 27 de marzo los alumnos del Máster de Ecología Marina de la Universitat de les Illes Balears, Miquel Àngel Nadal y Fernando Estarellas, defendieron sus respectivas tesis de máster, relacionadas ambas con la problemática de los microplásticos en el medio marino y dirigidas por Salud Deudero, investigadora del Centro Oceanográfico de Baleares del IEO.

• Evaluation and quantification of microplastic ingestion by semipelagic Boops boops (L.) individuals around the Balearic Sea. Miquel Àngel Nadal Nebot.

  

  Abstract: Microplastics litter has been recognized as a pervasive type of pollution in marine habitats worldwide and considered a global environmental problem. Laboratory studies of plastic ingestion have reported incidences in different marine organisms, including marine mammals, seabirds, turtles, fish and also plankton. This study is the first to document ingestion and quantify the amount of microplastic litter found in gastrointestinal tracts of Boops boops fish species from the Balearic Islands. From 337 fish captured from March to May in two localities in Mallorca island (Cap Blanc and Cala Ratjada) and two localities in Eivissa island (Espardell and Cala Tarida), microplastic filaments were found in 57.86% of gastrointestinal tracts analyzed of Boops boops. Of the 195 fish that had ingested microplastic the average number of pieces per fish was of 3.75(0.25). A total of 731 filaments of microplastics were identified using stereomicroscope techniques. The occurrence of microplastic litter among the food ingested was high; the frequency of occurrence was of 42.22% and 60% in Cap Blanc and Cala Ratjada, respectively, while in Espardell and Cala Tarida it was of 80.43% and 77.27%. In areas of Eivissa a total of 399 ingested microplastic filaments were recorded, in contrast to areas of Mallorca, where 332 microplastic filaments were reported. This results suggest a higher proportion of affectation around Eivissa island. In addition, in Mallorca it has been seen that there are less affected Boops boops individuals but those individuals affected, ingest a higher number of microplastics. The finding of plastic ingestion and posterior quantification of microplastics consumed by over 50% of Boops boops individuals of the Balearic Sea provides new data of the state of this sea and remarks the existing problems and the impacts which plastic litter from anthropogenic activities have on the marine environment.

• Análisis de microplásticos en el sedimento costero de las Baleares y su interacción con Holothuria forskali (Chiaje, 1823). Fernando Estarellas Calderón.

  

  Abstract: Almost all environments worldwide are contaminated by marine debris, especially plastics. There is now a greater concern for small plastic fragments, known as micro-plastics (synthetic polymer particles minor than 5 mm in diameter. In recent years the concentration of these micro-plastics has increased to 100 times, still a threat to the environment and marine organisms, due to their difficult extraction, their potential to enter the food chain and transfer persistent contaminants to organisms that ingest their toxicity resulting from its composition and its ability to carry non-native species. Because of their size, these may be ingested microplastic in the middle by a wide range of organisms (annelids, crustaceans, fish, whales) .It has been demonstrated that biofilms usually accumulate microplastic and traces of organic matter which are mixed with sediment, may well be ingested by organisms such as Holothuria sedimentívoros forskali. Previous studies conducted in laboratory showing that microplastic sedimentívoros can be ingested by organisms such as sea cucumbers, however no data on the abundance of micro-plastics in natural populations. In this paper we have analyzed the presence and amount of micro-plastics in the droppings of Holothuria forskali and the subtidal sediments of the Balearic Islands, since virtually no data on the distribution and dispersion of micro-plastics in the Mediterranean. In this study we sampled two areas with different degrees of protection and anthropological impact. One area is located in the National Park of the archipelago of Cabrera, this area contains areas with different degrees of protection: "Marine Protected Area Special Uses" and "Marine Protected Area Integral Reserve"; the other study area is located in the port of Andratx, an area considered "Non Protected" and more human pressure. Microplastic were observed in all samples analyzed sediment, so it is an abundant and ubiquitous residue sediment. The maximum values of abundance of micro-plastics have been observed in Santa Maria (Marine Protected Area Integral Reserve) 840 ± 170 microplastic / kg dry sediment. and an average of 260 ± 136 microplastic / kg of dry sediment.