A correlation between optical properties from satellite data and some indicators of eutrophication in Lake Garda (Italy)

Here we present the first results of a research project in the field of optical remote sensing from a satellite platform to monitor the lacustrine environment. Landsat Thematic Mapper imagery was considered, on the basis of good performances in the visible bands, which is particularly useful for studies of water quality. The study involves Lake Garda (Italy) and concerns the correlation between remote sensing observations of the surface characteristics of water bodies and the eutrophication trend, as derived from bottom sediment cores. Image processing provided radiance-derived quantities, by means of transects, from the shoreline to the pelagic environment, in two separate sub-basins marked by different eutrophication. A correlation between the recent and present eutrophication trends and the optical properties of the water, as seen by remote sensing, was observed. This approach can be seen as a new remote sensing application to the study of lacustrine environments, since it permitted a comparison of instantaneous information, taken from a space platform, with a long-term data set obtained from sediments deposited at the bottom of the lake.