Discipline: Biological Sciences
Subcategory: Pollution/Toxic Substances/Waste
Phillicia Killebrew - Norfolk State University
Agricultural water pollution affects the vitality and diversity of aquatic environments and organisms. A major source of this pollution is ammonium nitrate, which enters our waterways via water runoff, groundwater contamination, and brush fires. This study evaluated the toxicity of ammonium nitrate and how it is affected by the physical parameters: pH, temperature, and bacteria, within aquatic environments. Lithobates catesbiana tadpoles were rinsed in sterile water and the mucus coats were swabbed to collect bacteria. The bacteria were cultured on nutrient agar plates and assessed to determine the natural flora of the tadpoles. The tadpoles, in Gosner stages 36-38, were placed into four tanks and ammonium nitrate was added, in concentrations of: 1.9mg/L, 10mg/L, and 17mg/L, with a fourth serving as a control. The tanks were examined and tested daily for ammonia concentrations, pH, temperature and observed for death. Increased pH, temperature and ammonia concentration compromised the bacterial flora of the tadpoles. Acute toxicity was observed after 21 days. Mortality rates of 62.5%, in concentrations, 17mg/L and 10mg/L. These factors acted independently and dependently. The pH decreased and the temperature increased these dependent variable affected the toxicity. Fluorescent spectroscopy demonstrated the ammonia concentrations increased consistently. The importance of this study demonstrated that environmental water pollution in our nation?s waterways affects the vitality and diversity of aquatic environments and organisms.
Not SubmittedFunder Acknowledgement(s): National Science Foundation (NSF)
Faculty Advisor: Maureen Scott, mscott@nsu.edu
Role: I was present for the entire research process.