Figure 14

Relations between biomanipulation effects, lake properties and measures of intervention strength. Colours indicate whether changes of lake properties or intervention strength tend to strengthen or weaken the ability of biomanipulation to improve water quality (i.e. its ability to increase the Secchi depth or decrease the chlorophyll a concentration). Some of the meta-regressions summarised here are also presented in Additional file 12. The significance of the relations is indicated with one (p < 0.05), two (p < 0.01) or three (p < 0.001) asterisks. Lake areas, mean depths, retention times, pre-manipulation TP concentrations and fish removals were log-transformed. All analyses used the selected dataset with stocking-only biomanipulations excluded.