Phosphorus speciation and C:N:P stoichiometry of functional organic matter fractions in temperate forest soils

Background and aims Phosphorus (P) availability is crucial for forest ecosystem productivity and soil organic matter (SOM) is an important source for P. This study was conducted to reveal carbon (C), nitrogen (N) and P distributions in functional SOM fractions. We hypothesised that (1) most of the organic P (Porg) is part of the particulate SOM, (2) particulate SOM stores increasing share of P with decreasing soil P content and (3) the C:Porg ratio of mineral-associated SOM is smaller than that of particulate SOM.