Composition of the Low Molecular Weight Metabolome of Potamogeton perfoliatus (Potamogetonaceae) as an Indicator of the Transformation of the Ecological State of the Littoral Zone

The composition and nature of changes in the low-molecular-weight metabolome (LMWM) of Potamogeton perfoliatus L. growing in six biotopes of Lake Ladoga with different types of anthropogenic load have been analyzed. According to the results, it is found that the total number of low-molecular-weight organic compounds (LMWOCs) in the P. perfoliatus LMWM composition is directly dependent on anthropogenic load, which is well marked by the development of cyanobacteria. The greater the intensity of pollution or eutrophication of waters, or the higher the number of cyanobacteria, the lower the total number of LMWOCs and their concentration. A strongly pronounced dependence of the total concentrations of groups of LMWM compounds on the anthropogenic disturbance of the biotope and the concentration of cyanobacteria is revealed. A decrease in the number, relative amount, total concentration of carboxylic acids, and number and content of unsaturated fatty acids and an increase in the composition and content of phenols and the total content of aldehydes and ketones depends on an increase in anthropogenic pressure. The specific composition of the LMWM of claspingleaf pondweed depends on its response to biotic and abiotic factors of the aquatic (including anthropogenic) environment. The features of the change in the composition of the P. perfoliatus LMWM make it possible to use it as an integral indicator of the anthropogenic impact on the littoral biotopes of water bodies and the deterioration of their ecological state.