摘要：Sea eutrophication is a natural process, however in many cases is considered one of the major forms of water pollution affecting coastal areas, lakes and reservoirs all over the world. Many methodologies have been developed for assessing eutrophication and during the last decades, the contribution of remote sensing techniques has been proved very useful in this research area. Satellite data from various sensors have been processed and analysed by research groups all over the world for estimating chlorophyll a concentrations and consequently, eutrophication conditions in the marine environment. Further analysis of the spatial structure of the eutrophication phenomenon that includes detection of the degree of homogeneity and of the directions of maximum / minimum anisotropy is of great interest as well. In this study, an attempt was carried out for estimating the anisotropy in chlorophyll a spatial distributions produced by the process of satellite data. The North Aegean Sea was used as the case study area and SeaWiFS monthly satellite data acquired for February, May, July and September 2003 were analysed. As a result, four eutrophication maps illustrating the eutrophication levels in the North Aegean Sea were developed and further analysis of their spatial structure was carried out using variograms. Semi- and surface variograms were developed and the directions of minimum / maximum anisotropy as well as the degree of spatial correlation of the eutrophication phenomenon were assessed.
关键词：marine eutrophication; remote sensing; SeaWiFS; variograms; North Aegean
