Lauren Johnson—student of Trinity University in San Antonio, Texas—was awarded the MBL Associates Prize for Excellence in Independent Research in the Semester in Environmental Science (SES). The prize, sponsored by Friends of the MBL, was awarded based on her presentation at the 23rd annual SES student research symposium, which was held at the MBL in December 2019.  Johnson's research explored the effects of nutrients and agitation on carbon update and isotopic composition in the macroalga Ulva lactuca.

Lauren Johnson

According to her advisor, MBL Research Scientist Javier Lloret, Johnson's work provided "fresh insights" into claims in the literature that Ulva can switch between 3-carbon and 4-carbon photosynthetic pathways during nutrient limitation. Evidence for this "switch" has been based on changes in the isotopic composition of the algae thought to occur when high nutrient supply stimulates rapid algae growth. Johnson demonstrated that similar isotopic changes could also be induced by diffusion limitation of carbon uptake.

"Lauren did a superb job of fielding questions after her presentation," said Lloret.