Detection, identification and mapping of cyanobacteria — Using remote sensing to measure the optical quality of turbid inland waters

Abstract

The advantages of airborne scanning for the detection, identification and mapping of algal species, cyanobacteria and associated water parameters (such as turbidity) can be realized if current research outcomes are developed into operational methods based on images with high spectral resolution. Evidence for this has become available through data obtained recently in Australia from the Compact Airborne Spectrographic Imager. This paper shows how pigments associated with cyanobacteria are detectable, even in the very turbid waters typical of eastern Australia. It demonstrates how, if the waterbodies and their constituents can be characterized by a programme of field and laboratory measurement, current processing techniques and models allow the concentrations of different constituents (algae and particles) in the photic zone to be estimated and mapped. The challenge for operational remote sensing of optical water quality in Australia (and throughout the world) is seen to have two components. One is to provide an effective characterization of the target inland and adjacent coastal waters and the other is to streamline the data analysis to provide maps of water properties in the time and cost frameworks required for operational use.