Bio-optical properties of North-European turbid lakes

Optical remote sensing has become a useful tool for monitoring the aquatic environment. However, the quantitative interpretation of the satellite data in coastal waters and lakes is still complicated; consequently, in situ measurements retain their value. These data elucidate the connections between the types of lakes and environmental as well as climatic conditions. The purpose of the present work was to investigate the optical properties of North European lakes and to specify the peculiarities of turbid lakes. The main database was collected in three turbid Estonian lakes (Peipsi, Võrtsjärv and Harku), but also the data obtained from 22 southern Swedish lakes, 14 Estonian lakes and 15 southern Finnish lakes were used. Besides the analysis of the water samples special attention was paid to the attenuation of solar light in the water and the parameters describing this process. The results obtained in the present study definitely have an importance in ecological and climatic investigations, and they could be used for the further development of remote sensing algorithms in turbid and humic water bodies.