Changes in cation concentrations in red spruce wood decayed by brown rot and white rot fungi

Red spruce (Picea rubens Sarg.) wood blocks were incubated in modified soil block jars and inoculated with one of nine white rot or brown rot basidiomycetes. Concentrations of calcium, magnesium, potassium, iron, and aluminum were determined using inductively coupled plasma emission spectroscopy in wood incubated 0, 1.5, 4, and 8 months after inoculation. Concentrations of calcium and magnesium tended to increase with time in a linear fashion in wood inoculated with fungi. Patterns of change in potassium concentrations varied. Concentrations of iron and aluminum were high in wood decayed by some of the fungi, particularly Postia placenta (Fr.) M. Larsen & Lombard. Temporal trends in wood cation concentration varied among decay fungi tested, indicating that species of decay fungus should be considered when examining the role of wood decay in nutrient cycling in the forest.