Yiyi Li1
1University of Tsukuba, Japan
Sea urchins are key species within marine benthic communities, playing a critical ecological role in controlling habitat structure and shaping community composition. However, recent studies on ocean acidification (OA) have highlighted that elevated anthropogenic-driven pCO2 levels in seawater can compromise the physiological and ecological performance of calcifying species, including sea urchins. To better understand the effect of OA on sea urchins, we conducted an incubation experiment on two locally dominant species, Echinometra sp. A and Diadema setosum, under present-day and four elevated pCO2 treatments (ranging from pH 8.05 to 7.45). During the incubation period, we measured their growth, survival, metabolic rate (oxygen consumption) and feeding intake at different timepoints to assess whether their responses change with increasing exposure to the elevated pCO2 conditions. Results indicated that the effects of OA appeared to differ between the two sea urchin species. Both species showed some short-term resistance to acidic environments as their oxygen consumption rate remained relatively similar to present-day conditions. Yet, food intake generally decreased with increasingly elevated levels of pCO2. These findings enhance our understanding of the physiological impacts of OA on calcifying benthic animals and provide insights into potential changes in sea urchin community composition under future OA scenarios.
Biography
Yiyi Li is a first-year PhD student at the Shimoda Marine Research Center at the University of Tsukuba in Japan. Previously, she was studying how ocean acidification affects coralline chemical cues and sea urchin larval settlement for her master’s degree. Currently, her research focuses on the physiological and ecological responses of marine benthic organisms to climate changes, especially ocean acidification, to understand the benthic ecosystem structure and functioning under future scenarios.