We review published data of re-oligotrophication studies in different types of lakes and discuss whether re-oligotrophication by phosphorus reduction measures can affect seston quality in lakes due to an increase in C:P ratios of food for zooplankton. We analyze whether such an increase in elemental ratio may give rise to a stoichiometric constraint or bottleneck for regulation of phytoplankton by zooplankton and thus cause a decrease in trophic transfer efficiency. Because seston C:P ratios of seston tend to decrease with increasing P concentration in lakes, i.e. by increasing eutrophication, the reverse may be true, i.e. the C:P ratio of the seston will increase when lakes become re-oligotrophicated by P reduction. This may imply lower food quality for P-demanding seston grazers, like Daphnia, which have both relatively low C:P ratios and are quite homeostatic with regard to C:P ratios. Consequently, the reduced grazer biomass may lead to lower grazing pr Most investigated lakes – both deep and shallow – responded by improvement in underwater light climate due to reduction of P loadings. Several compensatory mechanisms prevented the occurrence of a stoichiometric bottleneck for top-down control. From a few documented cases of both deep and shallow lakes, where seston stoichiometry, the presence of Daphnia and the trophic transfer efficiency were concurrently measured during the process of re-oligotrophication, we may conclude that the anticipated
Original languageEnglish
Pages (from-to)189-202
Issue number3-4
StatePublished - 2008

ID: 54472