DEVELOPING METHODS TO DIFFERENTIATE SPECIES AND ESTIMATE COVERAGE OF BENTHIC AUTOTROPHS IN THE POTOMAC USING DIGITAL IMAGING

Abstract

This study developed methods for the quantification of benthic autotroph coverage in the Upper Potomac using digital imagery captured with drone-mounted cameras. Submerged aquatic vegetation (SAV) is an integral part of freshwater ecosystems and the presence or absence and abundance of SAV can be used as a barometer for ecosystem health. Cyanobacteria blooms occur regularly in the Upper Potomac during summer months and may be releasing cyanotoxins into the water. Drone imagery offers an easy and inexpensive way of generating coverage estimate of SAV and cyanobacteria which can then be used to assess ecological conditions. This study was able to differentiate substrate and benthic autotrophs with imagery captured at low altitude with 3 and 5-band cameras. This study also offers suggestions for differentiating between SAV and cyanobacteria if equipment with finer spectral resolution is available.