Vertical characterization of particles in stratified lakes

Density stratification is a distinctive feature of lakes characterized by a less dense layer (epilimnion) on top of a denser water (hypolimnion) separated by a strong density jump (pycnocline) between them. While the main driver of thermal lake stratification is temperature, this phenomenon changes the vertical particles distribution, which in turn may affect lake stratification, when suspended particles (including both non-organic and organic ones) cause an overall increase in water column density. Sinking of particles to denser layers changes the sinking rates and may produce particle accumulation at the density interface (pycnocline) having important consequences for organic matter turnover. To investigate the interaction of the physical water properties and distribution of particles as a consequence of the stratification, we used in this study the particle tracking system UVP 6 (Under Vision Profiler) for particle characterization in a stratified Lake Stechlin, Berlin, Germany. The preliminary results, as expected, show that the particle abundance changes in concordance with temperature, which proves the dependency of particle characteristics (size and concentration) on the vertical temperature distribution.