“PH”INGERPRINTING WEST COAST TIDE POOLS: COMMUNITY METABOLISM BOTH DRIVES AND RESPONDS TO PH VARIABILITY
Coastal ecosystems are highly variable environments where restricted water motion, terrestrial influences, and feedbacks between benthic productivity and calcification strongly influence local biogeochemistry. To understand how climate change stressors, such as rising CO2, will impact biodiversity and ecosystem functioning in dynamic coastal ecosystems, we must understand how local physical and biological processes drive coastal biogeochemistry. Across sites in California and Oregon, we characterized algal and invertebrate community composition, quantified physical tide pool metrics, and conducted daytime and nighttime sampling to assess community metabolism rates in 15 tide pools at each site. Community composition significantly impacted pH variability: pH values were all greatest in pools with the highest cover of algae relative to invertebrates whereas physical pool characteristics had negligible to no impacts on pH. Further, the slope of the relationship between net ecosystem calcification and production increased as mean pH decreased, indicating that differences in community-driven calcification and production rates are likely the dominant drivers of pH variability in tide pools. A key finding of this study is that community metabolism both controls and responds to pH variability, complicating our ability to predict how ocean acidification will impact coastal ecosystems. However, our results also underscore the ability of intertidal algae to control local biogeochemistry, impact the biology and ecology of associated organisms, and potentially buffer coastal ecosystems from the threat of ocean acidification under changing climatic conditions.
Silbiger, N. J., University of California at Irvine, USA, firstname.lastname@example.org
Sorte, C. J., University of California at Irvine, USA, email@example.com
Location: 305 A/B
Presentation is given by student: No