Eutrophication and Salinization as Risk Factors in the Translocation Process of an Endangered Glacial Relict Species

Species translocation is an increasingly used method in active plant conservation, but its high costs and risk of failure highlight the need for prior research to support its effectiveness. Salix lapponum plantlets obtained through micropropagation were subjected to two biological experiments under laboratory conditions. The plants were watered with aqueous solutions of NaCl (Experiment 1) and N-NO3 (Experiment 2) for a period of four weeks. The experiments were designed to simulate processes occurring in the natural habitats of the species- increased substrate salinity and eutrophication. To determine the plant response to the presence of NaCl and N-NO3 in the soil substrate, various morpho-physiological traits were examined, including selected growth parameters, relative water content (RWC), photosynthetic pigment content, selected chlorophyll fluorescence parameters, reactive oxygen species (ROS) accumulation, antioxidant enzyme activity, and anthocyanin content. The results showed that both tested factors acted as abiotic stressors. Exposure to NaCl solutions of various concentrations led to a significant deterioration in morpho-physiological parameters, whereas low concentrations of nitrate nitrogen stimulated the growth of S. lapponum. In response to stress, the plants activated defense mechanisms such as increased anthocyanin synthesis, elevated antioxidant enzyme activity, and maintenance of a high relative water content.