Inorganic Fertilizer and Coral Bleaching Dr. Dan DiResta 9/7/05 Nancy Williams Neera Khurana Vijal Patel Danny Benito

Last Week We… Developed a standard curve for the Bradford Assay Used the Bradford Assay to find the milligrams of protein per gram of wet weight of polyps Compared our results to the other three groups

Group Comparisons All of the groups’ results were within a magnitude of 10 of eachother % difference from the average was calculated for each group

Purpose To find out if exposure to an excess concentration of nitrate over one month will cause coral bleaching in Xenia sp. We know that too little Nitrate can cause coral bleaching, but can too much do the same?

Hypothesis Ho: Upon increasing the concentration of nitrate in the tank to 1.5ppm, the zooxanthellae density and amount of chlorophyll will remain constant. H1: Upon increasing the concentration of nitrate in the tank to 1.5 ppm, the zooxanthellae density and amount of chlorophyll will drop.

Procedure Since the optimal concentration of nitrate for growth is below 1mg/L, we will increase the concentration to 1.5mg/L in the tank. Use provided nitrate kit to test the initial (ambient) nitrate concentration of the tanks. Calculate the amount of nitrate that needs to be added to 8L tank to achieve a concentration of 1.5 mg/L nitrate. Repeat step each Wednesday for 4 weeks, each time restoring the nitrate concentration to 1.5 mg/L. Test the corals for zooxanthellae density, protein concentration, and chlorophyll content on each Wednesday

Controls In the control tank, everything except for nitrate will remain constant. (light, salinity, pH, temperature, etc.)

Works Cited Cokos, B., Jones, S., McClanahan, T.R., Pietri, D., Steneck, R.S. Interaction Between Inorganic Nutrients and Organic Matter in Controlling Coral Reef Communities in Glovers Reef, Belize. Mar Poll Bull 2005 May; 50 (5): 566-575. Iglesias-Prieto, R., Rodriguez-Roman, A. Regulation of photochemical activity in cultured symbiotic dinoflagellates under nitrate limitation and deprivation. Mar Bio 2005 April; 146 (6): 1063-1073.