EISEN (CHEMISCHE ELEMENTE); EISENGRUPPE (MINERALOGIE); GEOCHEMISCHER KREISLAUF (GEOCHEMIE); EUTROPHE SEEN (HYDROLOGIE); DIAGENESE (ABLAGERUNGSMILIEU); MIKROORGANISMEN (BIOLOGIE); MODELL-EXPERIMENTE + MODELLE (OZEANOGRAPHIE); GREIFENSEE, SEE (KANTON ZÜRICH); IRON (CHEMICAL ELEMENTS); IRON GROUP (MINERALOGY); GEOCHEMICAL CYCLE (GEOCHEMISTRY); EUTROPHIC LAKES (HYDROLOGY); DIAGENESIS (SEDIMENTARY ENVIRONMENT); MICROORGANISMS (BIOLOGY); MODEL EXPERIMENTS + MODELS (OCEANOGRAPHY); LAKE OF GREIFENSEE (CANTON OF ZURICH)