Basics of nutrient cycling ORGANIC ORGANIC MATERIALS MATERIALS AVAILABLE UNAVAILABLE AS NUT IENTS AS NUTRIENTS Fossilization Living Coal. organisms. oil, detritus peat 月espiration, decomposition Assimilation excretion photosynthesi Erosion、burning of fossil fuels INORGANIC INORGANIC MATERIALS MATERIALS AVAILABLE AS NUTRIENTS Weathering, UNAVAILABLE erosion AS NUTR佳NTS Atmosphere. -。o1 Minerals water Formation of in rocks sedimentary rockBasics of nutrient cycling