Projects

The scientific research cooperation between the National Institute of Biology (project leader on the Slovenian side: Dr. Nataša Mori) and WasserCluster Lunz - Biologische Station (project leader on the Austrian side: Ass.Prof. Priv.Doz. Mag. Dr. Gabriele Weigelhofer) is co-financed by the Public Agency for Scientific Research and Innovation of the Republic of Slovenia.

Over the past decades, plastic production has increased dramatically, with estimates of production rates from 1.5 million tons in 1950 to 367 million tons in 2020. The widespread use of plastics in every segment of human lives results in the accumulation of high amounts of both larger plastic debris and microplastics (MPs, particles < 5 mm) in the environment. The main concerns about the presence of MPs in the environment are their persistence and durability, and harmful impacts on human health and other living creatures. For example, MPs can adsorb toxic organic pollutants, nanoparticles or metals from the environment, serve as a vector for invasive or pathogen microbial species and act as a reservoir for antibiotic-resistant and metal-resistant genes. Moreover, MPs in water environments offer a habitat for specific microbial communities (i.e. plastisphere) different from surrounding water and sediment communities. The occurrence of “plastisphere” together with MPs adverse effects on freshwater biota can have potential impacts on local and global biogeochemical cycles and ecosystem processes in freshwaters. Until now, the complex interaction between microbial communities as a key player in aquatic ecosystems and MPs, especially in freshwater, is poorly understood and needs to be further investigated. For example, pollution of freshwaters with MPs may have significant effects on the structure and function of aquatic sediment microbial communities. Amendment of sediments with polyethylene (PE), polyvinyl chloride (PVC), polyurethane foam (PUF) or polylactic acid (PLA) microplastics showed altered sediment microbial community composition and nitrogen cycling processes.

Many important ecosystem processes that are critical for stream ecosystems take place in the riverbed sediments, the hyporheic zone. MPs can accumulate in the hyporheic zones of streams exposed to municipal and industrial sewage effluents, affecting the natural biofilm community and changing microbial processes. However, so far, information on the effects of MPs accumulation on the microbial community and biogeochemical processes in the hyporheic zone are scarce. Our project aims at investigating the effects of MPs on the microbial community biomass, composition, and activity in hyporheic sediments. We will investigate changes in the biofilm community as well as changes in the nutrient and organic matter cycling in hyporheic sediments due to exposition to MPs via a laboratory column experiment. The study will provide scientific evidences about MP pollution impacts on self-purification processes in freshwaters which are one ot the most important ecosystem services nature deliver to human society.

The study is intended to initiate the scientific cooperation between the Austrian and Slovenian partners, exchange methods and know-how, and deliver first data as a base for a joint FWF WEAVE project, which will be written during proposed collaboration. Based on the results of the experiment, we will also prepare a common scientific paper on the role of MPs in benthic and hyporheic sediments and their effects on microbial and biogeochemical processes. Further cooperation possibilities are also within common participation in Horizon Europe projects or other funding schemes (LIFE, Interreg).