Abstract:
The study analyzes the influence of abiotic factors on the overgrowth of higher aquatic
vegetation in lakes of various origins within the protective zone of the Saralinsky section of the
Volga-Kama Nature Biosphere Reserve. The work examined 94 parameters, including
morphometric characteristics of the lakes, physicochemical properties of bottom sediments, and
hydrochemical indicators. Statistical data processing with Spearman's correlation coefficient
revealed key patterns. The proportion of the littoral zone correlates with the accumulation of
nitrogen (r = 0.77, p ( 0.05) and organic matter in bottom sediments (BS), which stimulates
vegetation development. The granulometric composition of the sediment affects plant
distribution: cattails dominate in silty sediments (correlation with clay: r = 0.72, p ( 0.05), while
reeds thrive in sandy sediments. As lake area increases, the concentration of pollutants
(ammonium, nitrates, phenols, COD) decreases due to the dilution effect (r = -0.62 to -0.74, p
( 0.05). Heavy overgrowth (50-95% of the water area) is associated with eutrophication,
increased pH in bottom sediments and water (r = 0.61-0.71, p ( 0.05), and phenol accumulation
in water (r = 0.81, p ( 0.05)
