Euphotic zone depth according to measurements of the photosynthetically active radiation profile of Lake Teletskoye in August 2023: regional features

Abstract

The work analyzed measurements of the profile of photosynthetically active radiation (PAR) in Lake Teletskoye, obtained in August 2023. It was found that in the areas where rivers flow into the lake, the rate of vertical attenuation of photosynthetically active radiation is less than in the rest lake aquatorium. The maximum values of 0.577 m^-1 were found in the northern part of the lake, the minimum - 0.247 m^-1 in the central part of the lake, exposed to the river Chelyush runoff. All this indicates that the main source of dissolved organic matter is the degradation processes of organic matter in the lake itself, which are not associated with its supply due to river runoff. An estimate of the average PAR value attributable to the upper mixed layer was obtained. The range of its variability was from 0.13 to 0.62, which is also associated with river inflow.