Summary: | Increased ocean acidity because of global warming has the potential to cause coral to bleach. Bleaching, or the loss of symbiotic dinoflagellates by coral and sea anemones, has also been linked to increased temperature and increased irradiance. Bleaching is caused by photoinhibition or the breakdown of the photosynthetic mechanism of the symbiotic zooanthellae of the corals and sea anemones. In this experiment, I explored the potential effects of anthropogenic carbon dioxide on the sea anemone, Aiptasia pallida. I hypothesized that individuals of the sea anemone Aiptasia pallida would bleach when exposed to artificial sea water with decreased pH. I bubbled CO2 through artificial sea water and set up three treatment groups (pH 8.1, pH 7.8, and pH 7.4). Contrary to my hypothesis, the anemones only bleached significantly when exposed to the pH 7.4 treatment level. While all anemones used in the experiment appeared smaller and generally less healthy than anemones maintained in an aquarium, this difference was most prominent in the pH 7.4 treatment level. My results indicate that the pH 7.8 treatment level may actually aid the vitality of the zooxanthellae and subsequently the anemone itself by providing the zooxanthellae with extra CO2 for photosynthesis.
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