This is a free event! Phytoplankton play an important role as the base of marine food webs and their productivity is heavily influenced by the availability of nutrients. Human activity can change the amount and type of nutrients introduced to the coastal ocean, impacting the structure and composition of phytoplankton communities. Examples of how human activity in southern California impacts phytoplankton communities will be discussed, including examples from the Orange County Sanitation District diversion of sewage effluent to a nearshore pipe during the fall of 2012. Bio: Dr. Erica Seubert completed her PhD at the University of Southern California in 2013 as a part of the laboratory of Dr. David Caron. Her work focuses on phytoplankton community dynamics, with a specialization in harmful algal blooms.