Deciphering the “Dissolved”: Ecological Roles of Aquatic Viruses

Abstract:

Viruses are an abundant and ubiquitous part of aquatic ecosystems, where they play critical roles in biogeochemical cycling and infect all organisms from the smallest bacteria to the largest charismatic megafauna. Viral ecologists have made great strides in understanding the abundance and diversity of aquatic viruses, as well as their roles in bacterial mortality and horizontal gene transfer. This talk will present data on viral diversity and spatial and temporal variability in Florida's freshwater springs and discuss current trends, limitations, and controversies in our thinking about viruses in aquatic ecosystems. The impact of viruses on aquatic biogeochemistry is most frequently evoked through the act of host lysis and relatively few studies have examined the contribution of viral particles themselves to the dissolved organic matter pool, which is operationally defined by its ability to pass through a 0.2 micron filter. This talk will present evidence for the recently proposed Ferrojan Horse Hypothesis, which suggests a potential role for viruses in oceanic iron cycling, and its implications for a wide range of ecosystems.