Particle aggregation in tropical reef ecosystems under local and global stressors
Local stressors such as coastal eutrophication in tropical ecosystems have long been assumed to be a key driver of detrimental community shifts in fringing and patch reefs at varying distances from the coast.
In combination with increasing global stressors such as high inorganic carbon concentrations the formation and settling of aggregates significantly increases and may contribute to the mortality of benthic organisms in coral reef ecosystems.
Two contrasting conditions, eutrophic coastal vs. oligotrophic outer shelf zones, were investigated in terms of nutrient dynamics, aggregate formation and sedimentation rates, as well as bacterial community composition.
Findings suggest that mechanisms of immediate nutrient uptake, aggregate formation and onsite sedimentation rates close to shore prevent an increase nutrient and organic matter loading to oligotrophic shelf waters and therefore mitigate major damage in coral reefs under constant anthropogenic pressure.