Identification and quantification of phosphate turnover indicators after long-term compost application – long-term and single season effects

Summary

Abstract Background and aims Soil organic phosphorus (P org ) is of interest for plant nutrition because it can comprise between 20 and 80% of total soil phosphate (P). This study aims to examine the effect of compost application on soil phosphatases and microbial biomass, which influence the P turnover and, furthermore, to examine the speciation of P org . Methods Soil from a long-term field experiment (since 1997) which compares compost application with inorganic fertilization was analyzed for calcium-acetate-lactate extractable P (CAL-P), Olsen-P, acid (Acid-P ase ) and alkaline (Alk-P ase ) phosphatase activity and microbial biomass P. P org speciation was additionally analyzed with liquid-state 31 P nuclear magnetic resonance spectroscopy ( 31 P-NMR). Results We found a significant in