Cyanobacterial Harmful Algal Blooms (cHABs) are an increasing threat to freshwater ecosystems because toxins may be produced and hypoxia may occur as the cyanobacterial cells decay. Understanding spatiotemporal variation in bloom development is crucial to protecting public health and the environment, but the methods used for this purpose in large lakes (satellites) are not effective in smaller lakes. We explore the utility of in-situ fluorometry for modeling spatiotemporal variation in three cHAB indicators (PC, Chl, and PC:Chl ratio) along the lotic-lentic gradient of small reservoirs in Southern Ohio.
Results/Conclusions
cHAB indicators varied significantly between reservoirs, were often very similar between sampling dates within each reservoir, but occasionally a very different pattern along the lotic-lentic gradient was observed. We were unable to consistently achieve stationarity prior to spectral analysis of any of the cHAB indicators we measured. These results suggest that in-situ fluorometry could be a useful tool for monitoring the development of cHABs in small waterbodies, but the monitoring plan should be customized on a lake by lake basis. Spectral analysis may not be possible using extrinsic (user-defined) methods and intrinsic methods, such as empirical mode decomposition, should be explored.