Use of satellite imagery to estimate surface chlorophyll a and Secchi disc depth of Bull Shoals Reservoir, Arkansas, USA

Landsat Thematic Mapper data were acquired for four flyby dates that coincided with field data collection of chlorophyll a and Secchi disc depth for Bull Shoals Reservoir, Arkansas, USA. Predictive models were developed for chlorophyll a from July 1994 (R-2 = 0.80) and December 1994 (R-2 = 0.84) data and for Secchi disc depth (R-2 = 0.96) from February 1995 data. These models were then tested using historic chlorophyll a data compiled from the previous ten years. The July 1994 model satisfactorily predicted chlorophyll a levels in six of the ten years and this improved to five out of five years when only summer seasons were considered. Phytoplankton analyses suggested an influence on algorithm development with respect to species composition at the time of satellite flyby.