Lab Report 2 Ailani Hernandez Ocean Acidification 10 04 2023 Materials and Methods The purpose of this lab of ocean acidification is to examine how acidity affects shells and how air pollution affects ocean acidification This experiment was conducted at Kownlton Marine Research Station on a small island off the east coast of Florida To collect readings specialized equipment and scuba gear are assembled and field equipment are put together Acropora intermedia nobilis and Porites lobata are the two forms of coral that are present in the 5 underwater tubes that make up the climate change field experiment site The tubes control the temperature of the water within while releasing ambient CO2 It is then observed how the water and the corals are affected by environmental changes In total 5 identical tubes are being utilized in this experiment Since Tube 1 was the control tube no adjustments were performed In Tube 2 the temperature of the testing environment was elevated by 3 C and the impacts of the environment were observed A higher CO2 exposure level of 750 ppm was programmed for Tube 3 In Tube 4 it was planned to have an elevated CO2 exposure of 750 ppm as well as an elevated temperature of 3 C The increased CO2 exposure in Tube 5 was set at 1500 ppm The interval between the next measurements was then around 6 months By inserting each tool into the airlock to acquire readings from within the control tube s Tube 1 first reading was obtained With the help of an underwater pulse amplitude modulated fluorometer Fv Fm a reading was collected The meter displayed the corals heath Green indicates healthy yellow indicates unhealthiness and red indicates extreme unhealthiness death The degree of the water acidity was then measured using an underwater pH meter Afterwards the underwater digital camera was used to acquire rough measurements Then observations regarding the dissolution of calcite were made using the underwater digital microscope Results Table 1 Measurements of temperature CO2 concentrations Fv Fm measurements pH levels bleaching percentages and calcite dissolution for Acropora and Porite Tubes Time months pCO2 ppm Temp C pH Acropora Porites Acropora Porites Acropora Porites Fv Fm Fv Fm bleach bleach Cal Dis Cal Dis 8 05 Green Green N A N A Control Control Tube 2 Tube 3 Tube 4 Tube 5 Control Control Tube 3 Tube 5 Tube 2 Tube 4 0 6 6 6 6 6 0 6 6 6 6 6 400 400 400 750 750 1500 400 400 750 1500 400 750 25 25 28 25 28 25 25 25 25 25 28 28 8 05 8 05 7 82 7 82 7 55 Green Green Yellow Yellow Yellow Yellow Red Red Red Red 8 05 7 82 7 55 8 05 7 82 Green Green Yellow Yellow Red Red Yellow Yellow Red Red 0 0 15 7 29 30 0 0 7 30 15 29 0 0 9 3 22 20 0 0 3 20 9 22 No Change No Change Small Change Small Change Large Change No Change No Change Small Change Small Change Large Change No Change Small Change Large Change No Change Small Change No Change Small Change Large Change No Change Small Change Table 2 Measurements of temperature CO2 concentrations Fv Fm measurements pH levels bleaching percentages and calcite dissolution for Acropora and Porite Tubes Time months pCO2 ppm Temp C pH Acropora Porites Acropora Porites Acropora Porites Fv Fm Fv Fm bleach bleach Cal Dis Cal Dis 8 05 Green Green N A N A Figure 1 A measurement of the changes in pH balance caused by rising CO2 levels Figure 2 The percent bleaching of Acropora and Porites as a function of pCO2 levels Figure 3 The percent bleaching of Acropora and Porites as a function of pH balances Discussion and Conclusions Looking at the graphs we can see that a drop in acidity corresponds to a drop in the bleaching percentage In Acropora the percentage reduces to 7 when the pH level rises from 7 55 to 7 82 At 25 it appears to diminish more quickly in Acropora than in Porites but remains the same rate at 28 It can be seen that pH becomes less acidic as pCO2 levels rise Bleaching percentage appears to be significantly influenced by temperature The percentage of bleaching in both increases as temperature rises but pCO2 stays the same Acropora grows noticeably more than Porites when pCO2 is likewise elevated As for calcite dissolution it shows that as you increase the pCO2 levels it begins to create a change in those calcite dissolutions for both Acropora and Porites It may be concluded that warmer and CO2 richer settings will be detrimental to the coral ecology Some consequences of these global warming is coral bleaching leaving these corals to be vulnerable and making it much more difficult for them to reproduce and end up dying off