DrCayelanCarey
Experimentalcyanobacterialbloomscanincreasethebiomass,richness,diversity,andstabilityoftheeukaryoticphytoplanktoncommunityCyanobacterialbloomsareincreasinggloballyinmanyfreshwaterlakes,botheutrophicandoligotrophic.Freshwatercyanobacteriagenerallyhavenegativeeffectsoneukaryoticphytoplanktonineutrophiclakesbecauseoftheirabilitytoformdensesurfacescumsthatreducelightavailability.However,lessisknownabouttheeffectsofcyanobacteriaonotherphytoplanktoninoligotrophiclakes.WeconductedseveralexperimentsmanipulatingthedensityofGloeotrichiaechinulata,alargecolonialcyanobacteriumthatisincreasinglyobservedinlow-nutrientlakesinthenortheasternUnitedStatesandCanada.Inlow-nutrientmesocosms,Gloeotrichiaincreasedthebiomass,richness,anddiversityofotherphytoplankton,likelybecauseitincreasednitrogenandphosphorusconcentrationsinthemesocosms.Interestingly,wealsoobservedthatGloeotrichiastabilizedthecompositionoftheeukaryoticphytoplanktoncommunity:theno-Gloeotrichiacontroltreatmentexhibitedgreatermultivariatedispe