Adaptacje zooplanktonu do wybranych zanieczyszczeń w miejskich zbiornikach wodnych

Abstract

Application of road salt during winter is a routine measure in countries of the northern hemisphere. Elevated salinity has toxic effects on freshwater organisms, including a key link in freshwater foodwebs – cladocerans from the Daphnia genus. Therefore, it becomes necessary to understand the threats that road salt and its substitutes pose to freshwater ecosystems, and to search for innovative solutions to reduce road salt pollution. This dissertation presents the results of field and laboratory studies that shed light on the problem of road salt pollution. Field studies conducted on four urban ponds located in Lodz showed that the problem of road salt pollution was not limited to the winter period - elevated concentrations of chloride ions persisted in the water during the spring months as well. Moreover, based on natural ecosystems, it was possible to observe a negative correlation between zooplankton density and chloride ion concentrations in water exceeding chronic concentrations. However, it was the characteristics of the ponds that were the main factor determining the density of zooplankton in the studied ponds. Laboratory studies showed that elevated NaCl concentrations were a main factor determining in the hatching success of Daphnia magna and Thamnocephalus platyurus from spore eggs. Laboratory studies using Juncus effesus and Schoenoplectus lacustris have indicated the phytodesalinization potential of these species, which creates a possibility for future use of these plants in nature-based solutions, such as constructed wetlands, that could mitigate the road salt pollution.