Microplastics are plastic particles ranging in size from 1 µm to 1 mm. They can be composed of different types of polymers and come in a variety of shapes and sizes. Microplastics are found in aquatic ecosystems, where they are affected by biotic and abiotic factors that change their properties. The main source of microplastics in the aquatic environment are wastewater treatment plants, which receive microplastic particles mainly from cosmetics and fibres from synthetic clothing. Most of recent studies have confirmed the impact of microplastics on aquatic organisms, especially aquatic animals such as fish and water fleas, but the impact on aquatic plants has not been well understood yet.
In this context, the aim of this diploma thesis was to determine the effects of microplastics on the aquatic plant duckweed Lemna minor, in particular the specific growth rate of the plant, the length of its roots and the content of photosynthetic pigments. We used two types of polyethylene microspheres extracted from cosmetic products; pristine microplastics and aged microplastics which was subjected to an ageing process in surface water. Microplastics did not have negative effects on the specific growth rate of duckweed. On the other hand, microplastics effected root length and concentration of photosynthetic pigments. Therefore, based on results, we confirmed that microplastics can negatively affect duckweed. This demonstrated that the presence of microplastics in ecosystems is a serious problem that we will need to address more in the future, for our own benefit and for the benefit of other organisms in the entire environment.
|