Stormwater runoff drives viral community composition changes in inland freshwaters

Abstract

Storm events impact freshwater microbial communities by transporting terrestrial viruses and other microbes to freshwater systems, and by potentially resuspending microbes from bottom sediments. The magnitude of these impacts on freshwater ecosystems is unknown and largely unexplored. Field studies carried out at two discrete sites in coastal Virginia (USA) were used to characterize the viral load carried by runoff and to test the hypothesis that terrestrial viruses introduced through stormwater runoff change the composition of freshwater microbial communities. Field data gathered from an agricultural watershed indicated that primary runoff can contain viral densities approximating those of receiving waters. Furthermore, viruses attached to suspended colloids made up a large fraction of the total load, particularly in early stages of the storm. At a second field site (stormwater retention pond), RAPD-PCR profiling showed that the viral community of the pond changed dramatically over the course of two intense storms while relatively little change was observed over similar time scales in the absence of disturbance. Comparisons of planktonic and particle-associated viral communities revealed two completely distinct communities, suggesting that particle-associated viruses represent a potentially large and overlooked portion of aquatic viral abundance and diversity. Our findings show that stormwater runoff can quickly change the composition of freshwater microbial communities. Based on these findings, increased storms in the coastal mid-Atlantic region predicted by most climate change models will likely have important impacts on the structure and function of local freshwater microbial communities.

Effects of rainfalls variability and physical–chemical parameters on enteroviruses in sewage and lagoon in Yopougon, Côte d’Ivoire

“…As reported by many authors, SPM appears to be an important natural vehicle and a contribution to the survival of viruses in water (Rossi and Aragno 1999;Williamson et al 2014). Our work, performed on different sewage collection sites of the channel and lagoon seem demonstrate the existence of a significant and positive correlation between SPM and viral concentration in the lagoon environment.…”

Spatial and temporal dynamics of virioplankton in a high mountain tropical reservoir, El Neusa (Cundinamarca, Colombia)

“…VPR values from surficial littoral locations showed significant correspondences with the hydraulic volume of reservoir and precipitation levels (Spearman ρ = -0.68 and 0.55, respectively, P < 0.05). We believe that during the strongest rainfall levels (91-195 mm month -1 ) since September to November 2004 and April 2005, the entrance of allochthonous substrates by run-off or river discharges might stimulate the induction of lytic cycle in lysogenic prokaryotes or favor the exportation of certain allochthonous populations from land (e.g., Bergström & Jansson, 2000;Hewson et al, 2012;Williamson et al, 2014). In the limnetic locations, some high VPR peaks seem to be non-statistically related to rainfall and also with conditions of low water column stability, but an unexpected high value in December could be attributed possibly to the permanence of low temperatures (<16°C) in the water column (Fig.…”

Virus Ecology and Disturbances: Impact of Environmental Disruption on the Viruses of Microorganisms

“…Storms are a powerful macro-scale disturbance to any system, and Williamson et al examines the effect of stormwater runoff and the viruses therein on freshwater microbial communities (Williamson et al, 2014). Unique to this study is consideration of both the planktonic and particle-associated viral communities.…”