Abstract: Most of the world’s population live within 100km of a coastline and depend on coastal marine ecosystems for sustenance, shoreline protection, and economic resources. Because our shorelines are threatened by numerous local and global human impacts, it is essential to understand how they will change in the future. Coastal ecosystems persist in a highly dynamic environment, especially with respect to pH. This high variability of pH is driven by complex physical and biological processes that complicate climate change predictions. Using coral reefs and rocky intertidal ecosystems as examples, I discuss several case studies that highlight how pH, in combination with other anthropogenic stressors, affect ecosystem functioning. Specifically, I focus on how ecosystem function is affected by natural pH variability across multiple spatial scales, biological feedbacks between pH and ecosystem metabolism, and how a local stressor (nutrient enrichment) affects biologically-driven pH dynamics. Understanding the natural variability of coastal ecosystems and how organisms both drive and respond to changes in pH is necessary to project how ecosystem functioning will change in the future.

Biography: Nyssa Silbiger is a marine ecologist who uses a diverse set of laboratory, field, and quantitative techniques to understand the impact of climate stressors on organisms, communities, and ecosystem processes in the context of natural variability. Her love for ocean science began at Florida State University, where she conducted research on fiddler crab physiology and sea anemone-cleaner shrimp symbioses. She then earned her Masters of Science in Marine Sciences at the University of North Carolina at Chapel Hill, where she studied how reef sponges affect macroalgal growth by increasing nutrient concentrations. Her PhD at the University of Hawaii at Manoa focused on drivers of coral reef accretion and bioerosion and her postdoctoral research at the University of California, Irvine examined biological feedback loops in coastal ecosystems. Currently, she is an Assistant Professor at California State University, Northridge.