University of Natural Resources and Life Sciences, Vienna (BOKU) - Research portal
Gewählte Master / Diploma Thesis:
Sarah Layendecker
(2023):
Living in a polluted environment - Microplastic intake of the Eurasian otter (Lutra lutra) in different habitats along the river Inn.
Master / Diploma Thesis - Institut für Wildbiologie und Jagdwirtschaft (IWJ),
BOKU-Universität für Bodenkultur,
pp 57.
UB BOKU
obvsg
- Abstract:
- Plastic emissions are an environmental problem concerning habitats all around the world. Microplastics (< 5 mm) especially pose a threat to organisms as they can be mistaken for food. In several studies microplastics (MP) have been found in spraints (=faeces) of the Eurasian otter (Lutra lutra). The extraction methods however varied, exacerbating comparisons. This study aimed to develop a protocol specifically for MP extraction from spraints. This was done by comparing protocols for the digestion of sewage sludge and the extraction of MP from organic samples. Steps were evaluated based on applicability and adjusted accordingly. The final protocol showed a recovery rate of 84%. This protocol was applied to 50 spraints collected at five sampling sites along the river Inn. Visual analysis showed that 97 % of the samples contained MP, with 475 particles found. Road abrasion and microfibres were the most abundant particle shapes but fragments, pellets and conglomerates could also be detected throughout the sampling sites. Additionally to this method, 43 particles (> 0.5 mm) were analysed with ATR spectroscopy due to their sufficient size, out of which seven particles showed spectra associated with plastics. External analysis with FTIR spectroscopy of five samples showed that the most prevalent plastic types were polypropylene and polyethylene. Furthermore, the sampling sites were studied for potential drivers of MP emissions, namely human population density, road density, wastewater treatment plants and land use. The sites were then compared regarding these drivers as well as the MP load found in spraints. No significant differences were found in MP load in spraints between the five sampling sites, despite significant differences between the drivers of MP emissions. This indicates that different or more MP pollution drivers are acting in a complex aquatic food web. More research is needed into the effects of ingested MP for otters to evaluate current potential threats.
- Beurteilende*r: Nopp-Mayr Ursula
- 1.Mitwirkender: Sittenthaler Marcia