Georgia | Freshwater Research on Georgia’s Coastal Plain

Lead PI George Vellidis (UGA, Biological and Agricultural Engineering)
Co-PIs (current and past projects) Richard Lowrance (USDA-ARS), David Bosch (USDA-ARS), Susan Crow (UGA), Gary Hawkins (UGA), Catherine Pringle (UGA), Susan Reinhardt (UGA)
Graduate Students (UGA) Richard Carey (MS), Brian Gregory (MS), Casey Harris (MS), Andrew Mehring (PhD), Jason Todd (PhD)
Vellidis website
In collaboration with Dr. George Vellidis (UGA Tifton Agricultural Station), our lab has been doing research, on streams draining southern Georgia’s coastal plain, since the early 1990s.  Our early work was on the biogeochemical drivers and ecological consequences of low dissolved oxygen levels in coastal plain streams. The most common freshwater impairment on the coastal plain of Georgia is low dissolved oxygen (DO). The majority of water body segments listed on the 2004 303(d) list in the coastal plain of Georgia were in violation of DO standards established by the Georgia Environmental Protection Division. In fact, the highest percentage of DO-impaired streams in the US occurred in the southern coastal plain of Georgia. However, our collaborative research (conducted in three coastal plain watersheds) indicated that low DO in coastal plain streams was a natural condition for summer months.  Our lab was involved in hypothesis-driven research on causes and consequences of low dissolved oxygen in rivers, streams, and wetlands of the Georgia coastal plain (see Mehring et al. 2013; Todd et al. 2009, 2010; Carey et al. 2007).Our current research is focused on Salmonella, a harmful enterobacterium that can occur in water used to irrigate fruit and vegetable crops. We are working to identify how Salmonella is spread in the environment. This information is essential for agricultural management and food safety since Salmonella has caused recent outbreaks of foodborne illness from contaminated fruits and vegetables. Salmonella is capable of spreading between humans and wildlife, and it is also capable of surviving for long periods of time outside of any host. Objectives of our research include the following:

  1. Development of accurate and reliable water sampling protocols for use by farmers to test for Salmonella;
  2. Examination of storm runoff as a source of Salmonella in farm ponds that are used to store irrigation water;
  3. Assessment of crop contamination risks associated with irrigation splash water in crop fields; and
  4. Evaluation of wildlife as a potential source of Salmonella in farm landscapes.
Casey and samplerSouth Georgia agricultural pond