Christopher McGuire

I am interested in identifying human impacts on aquatic environments. I focus on the interface between terrestrial and marine systems, and evaluate phytoplankton, the base of the aquatic food web.  These tiny plant-like aquatic organisms may be affected by changes in many environmental variables, including light intensity, temperature, and nutrient availability. Human-sourced greenhouse gasses have caused atmospheric and oceanic temperatures to rise throughout the globe.  In addition, human dependence on intensive crop production has introduced elevated levels of nutrients into tributaries that reach the coastal ocean. Consequently, shifts in phytoplankton community structure have been observed and may continue be expected in the future.

My current projects focus on areas where excess nutrient loading generates negative ecosystem impacts.  Near the coastline of Huntington Beach, California, I participate in a collaborative study with the Orange County Sanitation District (OCSD) to monitor the effects of wastewater discharge into the coastal marine environment.  Here, I evaluate open water and point source outfall locations on a monthly basis to look for differences in phytoplankton assemblages and determine the threat of harmful algal species.  My second study site is the Salton Sea: a terminal body of water in Southern California fed primarily by agricultural runoff.  At this location, water quality conditions have declined so drastically that phytoplankton are now one of only a few organisms capable of sustaining life.  These study sites have potential to provide insight on how increased human impacts may affect aquatic environments in the coming decades.