LAUSR

ABSTRACT Kutser, T., Metsamaa, L., Vahtmäe, E. and Aps, R., 2007. Operative monitoring of the extent of dredging plumes in coastal ecosystems using MODIS satellite imagery. Journal of Coastal Research, SI 50 (Proceedings of the 9th International Coastal Symposium), 180 – 184. Gold Coast, Australia, ISSN 0749.0208 MODIS band 1 imagery is the only satellite data with acceptable spatial resolution (250 m) and sufficient revisit times (up to 4 times a day) potentially available for monitoring dredging plumes. The aim of this study was to determine the potential use of MODIS band 1 imagery in an optically sophisticated environment such as the Baltic Sea coastal waters for monitoring of total suspended matter in natural conditions and near dredging activities. It was found that there is linear correlation between MODIS band 1 (620-670 nm) reflectance and the total suspended matter concentration measured from water samples. The regression algorithm was used to produce suspended matter concentration maps and monitor dredging activities. The results showed that in such shallow water environments as the Estonian Coast resuspension caused by strong wind may increase the suspended matter concentration to the levels similar to those occurring during dredging. Areas affected by wind resuspension are much larger than the areas affected by dredging plumes. Therefore, the natural variability of suspended matter concentration has to be taken into account when estimating environmental impact of dredging activities on local ecosystems.