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In Situ and Remote Optical Monitoring of Aquatic Ecosystems

The field programme consisted of four Lake Erie research  cruises, in conjunction with Mr. M. Charlton, to collect data  consisting of optical parameters (spectral irradiance attenuation,  spectral remote sensing reflectance, and beam attenuation) along with  the concentrations of the main colour producing agents (chlorophyll,  dissolved organic carbon, and suspended sediments). Analysis of the  data has shown that the suspended sediments dominate the particulate  scattering and possess negligible optical absorption in the long  wavelength region of the visible spectrum.  Therefore, the  reflectance of the water body in the red is highly correlated with  the concentration of suspended sediments in the water column.  Interference by the presence of organic particulates was minimal for  the concentration ranges observed during the 4 cruises.      The determination of chlorophyll concentration from the  blue/green ratios of the aquatic reflectance, used in oceanic  studies, was found to be masked by the presence of dissolved organic  and suspended inorganic matter.   However, analyses of the in-situ  upwelling light spectra have shown that the measurement of the  chlorophyll fluorescence using three spectral bands, one coincident  with, and two adjacent to,  the fluorescence peak can be used to  estimate chlorophyll concentration in eastern Lake Erie.  Of major  importance to this methodology is that it may be applicable to  satellite imagery even if an accurate atmospheric correction cannot  be obtained for the imagery. Future research with assess the  applicability of these methodologies throughout the yearly biological  growth cycle and to the other Great Lakes. Results of this study can  lead to lakewide mapping of chlorophyll concentrations for each of  the Great Lakes.  These maps can be used to locate regions of high  nutrient (via the resultant high chlorophyll concentrations) as well  as estimate the primary productivity for each lake. 

In progress
Start Date
End Date
Scope of Study
Field Investigation
Scale of Phenomena
Natural Ecological Processes
Treatment / Manufacturing Processes
Valuation Study
Lake Basin Connecting Channels
Lake Erie
Lake Huron
Lake Ontario
Lake Superior
Purpose of Project
Program Effectiveness / Regulatory
Resource Being Monitored
Suspended Sediments
Annex Numbers
Surveillance and Monitoring

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