Differentiation of cyanophyte, algal and suspended sediment signatures in the 2015 CyanoHAB in Sandusky Bay, Lake Erie
Joseph D. Ortiz1, George S Bullerjahn2, Stephen Schiller3, Jeffrey C Luvall4, Kristen Slodysko1,5, Robert M McKay2, John Lekki6, Justin Chaffin7, Darren L Bade8, Dulcinea Avouris1, Taylor Tuttle2, Emily Davenport2, Fangyu Zheng1, Kyle Carey1, Shannon Hunter1, Amber Huston1 and Kalpani Manurangi Ratnayake1, (1)Kent State University Kent Campus, Geology, Kent, OH, United States, (2)Bowling Green State University, Biological Sciences, Bowling Green, OH, United States, (3)South Dakota State Univ, Physics, Brookings, SD, United States, (4)NASA MSFC NSSTC, Applied Science Team, Huntsville, AL, United States, (5)University of Washington, Environmental and Occupational Health Sciences, Seattle, WA, United States, (6)NASA Glenn Research Center, Optics and Photonics Branch, Cleveland, OH, United States, (7)Ohio State University, Stone Laboratory, Put-in-Bay, OH, United States, (8)Kent State University, Biological Sciences, Kent, OH, United States
Abstract:
Lake Erie and it's marginal basins have faced progressively severe CyanoHABs in recent years due to nutrient-driven eutrophication. The CyanoHAB in Sandusky Bay is more persistent that the bloom associated with the western basin of Lake Erie. The two blooms are driven by different dominant taxa. While the Western Basin bloom is associated with Microcystis, the dominant cyanophyte in the Sandusky bloom is Planktothrix. Here we present field data, which documents spatial and temporal differences in the cyanophyte and algal composition of these two blooms, and within the Sandusky Bloom.
This new method of hyperpsectral analysis developed in the Water Quality Lab at Kent State University allows the identification of phytoplankton and cyanophytes, suspended sediment and CDOM using visible derivative spectroscopy, a method with the potential to transform monitoring of algal composition and CyanoHABs in aquatic systems (Ortiz et al, 2013a,b, Ali et al. 2013, Ali et al. 2014). For example, we can differentiate the signature of Microcystis from that of Planktothrix. Our approach can be applied to multispectral and hyperspectral reflectance data collected in the field using handheld instruments, in the lab, or through airborne or satellite remote sensing. The results from our most recent field season indicate the 2015 CyanoHAB exhibited considerable bio-complexity, with contributions from several types of cyanophytes, algae, suspended sediment, and colored dissolved organic matter. By application of visible derivative spectroscopy to statistically decomposed visible hyperspectral data, we differentiate and quantify the relative proportion of various cyanophyte and algal components associated with the Sandusky bloom. Growth experiments from different sites in the bay document the presence of diatoms in the inner bay, with Planktothrix in the outer bay.
