Basics of nutrient cycling ORGANIC ORGANIC MATERIALS MATERIALS AVAILABLE NAVAI E AS NUTRIENTS AS NUTRIENTS Fossilization Living Coal organisms oil, detritus Respiration decompositi。n Assimilation excretion photosynthesis Erosion, burning of fossil fuels INORGANIC INORGANIC MATERIALS MATERIALS AVAILABLE AS NUTRIENTS Weathering, UNAVAILABLE erosion AS NUTRIENTS Atmosphere, soil, Minerals water Formation of in rocks sedimentary rock4 Basics of nutrient cycling