Natural and anthropogenic dispersal of cyanobacteria: a review

Abstract

Cyanobacteria are oxygenic photosynthetic organisms that are prevalent in freshwater and marine ecosystems. A proportion of the cyanobacteria in a given locality are known to be introduced from other regions and are able to cause harmful cyanobacterial blooms. However, the processes by which cyanobacteria is relocated are not well described. This review presents the various natural and anthropogenic methods of cyanobacterial transport, with emphasis on the dispersal of problematic taxa. Natural mechanisms for transport of cyanobacteria include meteorological phenomena such as dust storms and tsunamis, which facilitate the long-distance transport of cyanobacteria through the air and rafting debris in oceans, respectively. Cyanobacteria can also be transported by animals such as worms, seabirds and planktivorous fish. The influence of anthropogenic activities on cyanobacterial distributions is also discussed, with focus on transport through international shipping and on rafting surfaces provided by plastic pollution. In this study, a total of 150 species of cyanobacteria from 64 genera were identified to be transported across a combination of natural and anthropogenic methods. As cyanobacteria are organisms that are prevalent in many ecosystems, an understanding of these transport processes will allow for improved assessment and monitoring of introduced toxic cyanobacterial species.