Long-term variations of phytoplankton primary production in a shallow, polyhumic reservoir

Multiannual and seasonal variation of phytoplankton primary production parameters were investigated in a polymictic, polyhumic dam reservoir. High values of the gross production indicate increasing eutrophication of reservoir waters already from the first years of its existence. The predominance of the total respiration over the net production is caused by substantial natural loads of dissolved organic matter fed to the reservoir from the peaty-forest catchment.