Abiotic factors driving cyanobacterial biomass and composition under perennial bloom conditions in tropical latitudes

摘要: While warming and eutrophication have increased the frequency magnitude of harmful cyanobacterial blooms globally, scenario for many eutrophic tropical freshwaters is a perennial year-round bloom. Yet, drivers persistent are less understood when conditions such as light, temperature, nutrients favor cyanobacteria growth year-round, especially in regions facing recurrent periods drought. In order to understand dominance, we assessed abiotic related abundance dominance two dominant bloom-forming genera Raphidiopsis Microcystis, six shallow, man-made lakes located semiarid Northeastern region Brazil during prolonged regional Lower water level corresponded phosphorous nitrogen concentration and, consequently, phytoplankton biomass. Cyanobacterial biomass was also proportional phosphorus concentrations blooms. genera, seldom co-occurred temporally switch between them driven by transparency. Our results illustrate effects drought induced reductions on composition shallow lakes. Given ideal (i.e., high light temperature), droughts may be expected intensify risk multitude problems associated with eutrophication.