abstract
In forested streams, leaf litter decomposition is a vital ecosystem process, governed primarily by aquatic hyphomycetes. These fungi are crucial mediators of nutrients and energy to invertebrates and higher trophic levels. Very little information is available on the impact of low concentrations of different sizes of nanoplastic particles (NPPs) on leaf litter decomposition and aquatic hyphomycetes communities. Besides, NPPs impact on leaf litter nutritional quality and invertebrate feeding behaviour is unknown. We conducted a microcosm assay with varying concentrations (0-25 mu g L-1) of small (100 nm; SNPPs) and large (1000 nm; LNPPs) plastic particles to assess their impact on leaf litter decomposition, sporulation rates and community structure of aquatic hyphomycetes. Furthermore, leaf litter was retrieved and fed to invertebrates to assess feeding rates. Our results indicated that leaf litter decomposition, fungal sporulation and abundance were significantly affected by NPPs concentrations and sizes. By contrast, leaf litter nutritional quality was impacted only by sizes. The NPPs, particularly SNPPs, augmented leaf litter polyunsaturated fatty acids (18-31%), consequently improving food quality; however, invertebrates' feeding rates were not impacted. Overall, our study provides novel insights on the risks posed by NPPs with pronounced impact at the basal trophic level.
keywords
COPPER-OXIDE NANOPARTICLES; FATTY-ACIDS; BREAKDOWN; TOXICITY; FUNGI; MICROPARTICLES; MICROPLASTICS; PREFERENCES; INDUCTION; EMISSIONS
subject category
Engineering; Environmental Sciences & Ecology
authors
Seena, S; Gutierrez, IB; Barros, J; Nunes, C; Marques, JC; Kumar, S; Goncalves, AMM
our authors
acknowledgements
This work is financed by national funds through FCT-Foundation for Science and Technology, Portugal within the scope of the projects UIDB/04292/2020 granted to MARE-Marine and Environmental Sciences Centre and UIDP/50017/2020+UIDB/50017/2020 (by FCT/MTCES, Portugal) granted to CESAM-Centre for Environmental and Marine Studies, and CICECO-Aveiro Institute of Materials (UIDB/50011/2020 & UIDP/50011/2020) . Irene B. Gutierrez acknowledges the project POR-BIOTA, E-Infrastructure Portuguese Information and Research in Biodiversity (POCI-01-0145-FEDER-022127) , which co-financed this research supported by Competitiveness and Internationalization Oper-ational Programme and Regional Operational Programme of Lisbon, through FEDER-Fundo Europeu de Desenvolvimento Regional and FCT. S. Seena (IT057-18-7254) and A.M. M. Goncalves (IT057-18-7253) ac-knowledges the University of Coimbra for the contract. C. Nunes is supported by FCT, within the scope of the framework contract foreseen in the numbers 4, 5 and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19. N. Coimbra is also appreciated for assisting in field trips.