Abiotic-Biotic Interrelations in the Context of Stabilized Ecological Potential of Post-Mining Waters

The creation of man-made reservoirs has become more common globally and provides many important technical, biological, and socio-economic functions. The study focused on abiotic-biotic and trophic interrelations responsible for ecological potential and biodiversity in potentially stabilized conditions of the aquatic ecosystem. Therefore, the analyses concerned 2014-2015 and 2018-2019, assuming repeatable hydrochemical conditions, in three chambers (C1-C3) of the Kamien sedimentation pond supplied through opencast mine drainage. The studies indicated eutrophic levels and at least good ecological potential. Phytoplankton were quite abundant at an average biomass of 10.0 mg L-1, while zooplankton and planktivorous fish were estimated at 0.51 mg L-1 and 74.3 g m(-2), respectively The general order of the growth level in chambers was C-1 > C-2 > C-3, C-1 > C-2 > C-3, and C-1 < C-3 < C-2 for phytoplankton, zooplankton, and planktivorous fish, respectively, and indicated clear differences. Both mechanisms of the top-down and bottom-up effects were revealed in all chambers. Some significant differences between abiotic and biotic (i.e., fish density and biomass, phytoplankton density) factors were recorded on a temporal scale, whereas the density and biomass of planktivorous fish were significantly differentiated on a spatial scale. The stabilized conditions concerned relatively high biodiversity but quite abundant phytoplankton and lower zooplankton abundances, trophic efficiency, and eutrophy under the maximum ecological potential.