Plant pigments in woodland soils

Low concentrations of carotenoids and chlorophyll derivatives are present in the organic matter of surface horizons of woodland soils. Before leaf fall chlorophyll breaks down more rapidly than carotenoids, while the reverse is true in soils. Pigment concentrations in the organic matter of sediments from productive lakes are usually much higher than concentrations in the litter and humus layers of woodland soils. This suggests that the contribution of woodland litter and humus to the organic matter in such sediments is outweighed by contributions from aquatic macro-phytes and phytoplankton.