Discipline: Ecology Environmental and Earth Sciences
Subcategory: Microbiology/Immunology/Virology
Session: 3
Room: Exhibit Hall A
Nigel Veney - Norfolk State University
Co-Author(s): Diamond Liles, Norfolk State University, Norfolk, VA
Agriculture pollution is a global issue the major source of this pollution is ammonium nitrate pollutant accessing our waterways. Ammonium nitrate a major source of agriculture pollution is a byproduct of the fertilizer that pollutes aquatic environments from run offs in agriculture, industrial sites, landfills, and waste. The Environmental Protection Agency (EPA) mandates that 10 mg/L of ammonium nitrate is the highest level for human consumption and 17 mg/L is the chronic level for aquatic organisms. The purpose of this study is to use nitrifying bacteria (NB) to stabilize a polluted aquatic environment. This study will determine if ammonium nitrate pollutant toxicity can be modified by microbial bioremediation promoting the vitality and development of aquatic organisms. This study uses Lithobates catesbeinanus pre-metamorphic tadpoles in Gosner stage 30 because they are excellent environmental indicators. Tadpoles were exposed to ammonium nitrate concentrations daily for bioaccumulation: 10 mg/L (NB), 10 mg/L, 17 mg/L (NB), 17 mg/L, and a control tank. The nitrifying bacteria solution used in this study contained purified water, Nitrosomonas, Nitrosospira, and Nitrospira with the use of ceramic filtration methods. The water quality was tested weekly for ammonium/ammonia, nitrite, and nitrate levels. The other parameters observed were pH, dissolved oxygen, and temperature. Results demonstrate that ammonia toxicity correlates with lower pH levels, waste excretion, and ammonium nitrate pollutant. Nitrosomonas was active based on nitrite levels increasing in week two and during week three the increase levels of nitrate signaled Nitrobacter activity in the ammonium nitrate polluted tanks. Average dissolved oxygen level was 6.9 mg/L and temperature was 23.9?C the acceptable range for proper nitrification and development for the tadpoles. Results in this investigation depicted 100% mortality in the 10 mg/L ammonium nitrate without nitrifying bacteria and 40% mortality rate with nitrifying bacteria. The 17 mg/L with NB exhibited a negative microbial imbalance with 90% mortality rate. The 17 mg/L without NB had a 100% mortality with a higher nitrate level correlating with the presence of nitrifying bacteria. Tadpoles have reached Gosner’s stage 32 in the control tank. In future work, we plan to evaluate the standards for the amount of nitrifying bacteria required for different EPA levels of ammonium nitrate pollution for effective microbial bioremediation.
Funder Acknowledgement(s): I thank Mrs. Maureen Scott, NSU biology department, and STARS summer research. Funding was provided by the National Science Foundation #1000286
Faculty Advisor: Maureen Scott, mscott@nsu.edu
Role: Myself and the co author did all research work together. Prior to working in the lab I literature searched information pertaining to the research. I maintained the proper environment and parameters for the experimental subject, control, and nitrifying bacteria. while recording data daily on water quality after ammonium nitrate bioaccumulation using scientific instruments and mortalities within each experimental group. I observed the development of the tadpoles daily in comparison to the control group. Observing the aquatic organism development, microbial activity, and water quality I was able to accept or refute the hypothesis.