Incorporating Microbial Species Interaction in Management of Freshwater Toxic Cyanobacteria: A Systems Science Challenge

Abstract

Water resources are critically important, but also pose risks of exposure to toxic and pathogenic microbes. Increasingly, a concern is toxic cyanobacteria, which have been linked to the death and disease of humans, domesticated animals, and wildlife in freshwater systems worldwide. Management approaches successful at reducing cyanobacterial abundance and toxin production have tended to be short-term solutions applied on small scales (e.g., algaecide application) or solutions that entail difficult multifaceted investments (e.g., modification of landscape and land use to reduce nutrient inputs). However, implementation of these approaches can be undermined by microbial species interactions that (a) provide toxic cyanobacteria with protection against the method of control or (b) permit toxic cyanobacteria to be replaced by other significant microbial threats. Understanding these interactions is necessary to avoid such scenarios and can provide a framework for novel strategies to enhance freshwater resource management via systems science (e.g., pairing existing physical and chemical approaches against cyanobacteria with ecological strategies such as manipulation of natural enemies, targeting of facilitators, and reduction of benthic occupancy and recruitment). Here, we review pertinent examples of the interactions and highlight potential applications of what is known.

Toward a Brighter Future: Enhanced Sustainable Methods for Preventing Algal Blooms and Improving Water Quality

“…Future studies must focus on sustainable, innovative solutions that are both environmentally friendly and cost-effective. Methods such as nutrient reduction, biomanipulation, and the use of targeted, minimally disruptive algicides are highlighted [202,203].…”

Understanding the Risks of Diffusion of Cyanobacteria Toxins in Rivers, Lakes, and Potable Water

“…On the other side, cyanophages, a natural virus that feeds on cyanobacteria cells and infects them, can kill cyanobacteria when introduced into infected waters [ 310 ]. Other biocontrol strategies involve adding plant extracts or certain aquatic organisms to waters that are already infested [ 311 , 312 , 313 ]. Several plant extracts, including Salvinia molesta [ 313 , 314 , 315 ] inhibit cyanobacteria growth.…”

“…Other biocontrol strategies involve adding plant extracts or certain aquatic organisms to waters that are already infested [ 311 , 312 , 313 ]. Several plant extracts, including Salvinia molesta [ 313 , 314 , 315 ] inhibit cyanobacteria growth. Phytoplanktivorous fishes, including silver carp, big-head carp ( Hypophthalmichthys nobilis , previously Aristichys nobilis ) and tilapia ( Oreochromis niloticus ) are direct consumers of phytoplankton (including MC-producing M. aeruginosa ) and zooplankton, and thus are widely used in the non-traditional bio-manipulation of cyanobacterial blooms [ 142 ].…”