European Diatom Database-African Dataset

The European Diatom Database (EDDI) is a web-based information system designed to enhance the application of diatom analysis to problems of surface water acidification, eutrophication and climate change. The East African dataset and North African dataset were harmonized to construct a unified African data set. Transfer functions were developed from the subsequent training set for inferring past conductivity (r2= 0.87), pH (r2= 0.77), and ratios between alkali and alkaline earth metals (r2 = 0.81) and carbonate-bicarbonate and sulphate + chloride ions (r2 = 0,82) (Gasse et al., 1995) and the model has subsequently been applied to several diatom sequences to reconstruct lake chemistry (e.g. Fritz et al., 1999; Dagnachew et al., in press ; Chalie and Gasse, in press ; Gasse, 2001 ; Gasse, in press ; Verschuren et al., 2000 ).