Nutrient competition experiments with periphyton from the Baltic Sea

Nutrient competition experiments were performed with periphytic microalgae from the Kiel Fjord, western Baltic Sea.Diatoms were dominant competitors at high Si:N ratios (under N-limited conditions) and high Si:P ratios (under P-limited conditions) Under lo silicate supply, cyanobacteria became dominant at low N:P ratios and chlorophytes at h ~g h ones.Changes in light intensity ~nfluenced the outcome of competition at the species level but not at the level of higher taxa.The nitrogen source (ammonium or nitrate) had no impact on the outcome of competition.