A CASE STUDY OF HOW BIOLOGY RESPONDS TO AN INCREASINGLY HYPERSALINE ENVIRONMENT - An Li Logo

A CASE STUDY OF HOW BIOLOGY RESPONDS TO AN INCREASINGLY HYPERSALINE ENVIRONMENT - An Li

An Li 

University of Chicago, Chicago, IL, USA

@astroanli

California's largest lake, the Salton Sea, has been steadily drying up since 2003 and has nearly doubled in salinity over the last 20 years. Studying how life adapts in a highly salinated and changing environment like the Salton Sea serves as an important analog for how life may adapt in other increasingly salinated environments. Here, we examine how algal biomass in the Salton Sea has responded to increases in salinity and decreases in water area through time. We combined in situ surface chlorophyll and salinity data, lake area from Landsat 8, and surface chlorophyll concentrations from Landsat 8 and the Airborne Visible Infrared Imaging Spectrometer (AVIRIS) to examine how increasing salinity affected lake biology from 2013 to 2020. Overall chlorophyll trends between the three data sources are comparable and remote sensing results track in situ chlorophyll trends; however, additional in situ data is necessary to better quantify the relationship. While annual chlorophyll averages stayed relatively constant, we found a noticeable increase in the maximum annual average of chlorophyll by 1.1 ?g/L per year from 2013 to 2020 using Landsat 8. Other changing factors such as increasing phosphorus may have offset the negative effect of increased salinity on algal biomass during this time. Our findings demonstrate that remote sensing allows us to better track the biological responses in the lake under increasingly salinated conditions and suggest that biological organisms are (so far) adapting.