Chemistry and Dynamics of Soil Organic Phosphorus
This chapter presents an overview of the chemical nature of soil organic phosphorus (P) and its role in determining the dynamics, availability, and mobility of soil P in agroecosystems. It emphasizes recent advances, including the application of novel analytical techniques such as 31P nuclear magnetic resonance spectroscopy and isotope exchange and dilution, and the role of organic P in the transfer of soil P to watercourses in runoff. The transfer of P in drainage from agricultural soils to watercourses is a key component of the global P cycle, and has important implications for water quality, because the enrichment of receiving waters with P can contribute to eutrophication. It is clear that diffuse P pollution cannot be effectively managed without a comprehensive appreciation of the role of organic P. The determination of organic P in drainage waters is almost exclusively based on operationally defined procedures involving size separation and crude chemical speciation.