Transformation of organic phosphorus

Bowman, R.A. and Cole, C.V. (1 978)Transformations of organic phosphorus substrates in soils as evaluated by NaHCOj extraction. Soil Science 125, 49-54. 

In this chapter, we discuss the various approaches that have been used to determine organic phosphorus in the water column and sediments of aquatic ecosystems. We then review the limited number of studies that have examined transformations of organic phosphorus in aquatic ecosystems, and finally assess how organic phosphorus interacts with the aquatic cycles of other nutrients. 

The role of microorganisms in the transformation of organic phosphorus to inorganic phosphorus in soils has long been recognized. Microorganisms can influence DIP release in soils as follows ... 

Within the last decade it has become obvious that photochemical reactions play an important role in the transformations of organic matter. Most studies in this respect have focused on organic carbon. However, photochemical reactions are not restricted to carbon, but also affect other elements including nitrogen (see below), sulfur (e.g. Brugger et ah, 1998 Dierdre et ah, 2003 Hatton, 2002), phosphorus (observations limited to humic-rich lake water—see Mopper and Kieber, 2002), and metals (see Zepp, 2003). 

Oxidative processes play an important role in the degradation of organic phosphorus ester insecticides. However, one of the degradation product is often biologically more active than the parent compound. The oxidative activation of schradan is a typical example, and may serve as a guide of more general validity to the biochemical transformation of other N-alkyl phosphoroamidates. 

Gardolinski, P.C.F.C., Worsfold, P.J. and McKelvie, I.D. (2004) Seawater induced release and transformation of organic and inorganic phosphorus from river sediments. Water Research 38, 688-692. 

Structural studies and identification of organic phosphorus compounds by two-dimensional Fourier-transform ion cyclotron resonance mass spectrometry... 

When combined with NMR spectroscopy, NMR can be used to evaluate linkages between carbon and phosphorus transformations (Gressel etal., 1996 Moller et al., 2000). The main advantage of solution NMR spectroscopy is that it allows direct identification of organic phosphorus forms, although a proportion of the soil organic phosphorus remains unidentified due to its incomplete recovery from soil. In the future, this could be overcome by solid-state P NMR, but this is currently impractical due to low phosphorus concentrations and the presence of paramagnetic impurities, especially in tropical soils (Condron etal., 1997). 

Friesen, D.K. and Blair, G.J. (1988) A dual radiotracer study of transformations of organic, inorganic and plant residue phosphorus in soil in the presence and absence of plants. Australian Journal of Soil Research 26, 355-355. 

In terms of key interactions at the ecosystem level, it is expected that plant production and its associated effects on the amounts and transformations of organic carbon in the soil-plant system will have the greatest overall impact on the dynamics of organic phosphorus. The amounts, forms, distribution and associated dynamics of organic carbon and phosphorus in soil are influ-... 

While mechanistic studies of transformation processes are important, they must be complemented by kinetic data. The kinetics of these processes provides key information for interpretation of the importance of these processes for aquatic ecosystem ecology. Transformation rates of organic phosphorus need to be determined accurately with labelled substrates or other appropriate methods, because net rates of processing do not allow accurate interpretation of the cycling and importance of certain nutrient species. For example, Hudson et al. (2000) used a novel method to observe rapid turnover of organic phosphorus supporting high rates of production in the absence of phosphate. Traditional measures of net... 

This chapter reviews descriptions of organic phosphorus components and associated transformation processes as they are used in mechanistic models of aquatic systems. Different approaches have been developed for modelling organic phosphorus in lakes, rivers, sediments, marine systems and sewage treatment plants. A review of some... 

This section overviews the treatment of organic phosphorus transformation processes in biogeochemical models of lakes and rivers. Some milestones in the historical development are illustrated with represen-... 

An improved knowledge of the mechanisms and rates of organic phosphorus transformations, so that we can better predict the consequences of management interventions on organic phosphorus dynamics. 

Drawing on the latest research and opinion, this book contains state-of-the-art reviews of organic phosphorus characterization and transformations in the environment. It is aimed at scientists with an interest in nutrient dynamics in all fields of environmental science. The seventeen chapters are organized into three main sections. Section 1 describes analytical techniques used to characterize organic phosphorus compounds in environmental samples, with chapters dedicated to state-of-the-art procedures involving chromatographic separation, nuclear... 

Microbial biomass regulates storage and transformation of phosphorus, and flow of phosphorus through the soil microbial pool can be substantial. In phosphorus-limited wetlands containing significant quantities of organic phosphorus, bioavailability of phosphorus may be regulated by... 

Thionyl chloride and phosphorus tribromide are specialized reagents used to bring about particular functional group transformations For this reason we won t present the mechanisms by which they convert alcohols to alkyl halides but instead will limit our selves to those mechanisms that have broad applicability and enhance our knowledge of fundamental principles In those instances you will find that a mechanistic understand mg IS of great help m organizing the reaction types of organic chemistry... 

The analysis of phosphates and phosphonates is a considerably complex task due to the great variety of possible molecular structures. Phosphorus-containing anionics are nearly always available as mixtures dependent on the kind of synthesis carried out. For analytical separation the total amount of phosphorus in the molecule has to be ascertained. Thus, the organic and inorganic phosphorus is transformed to orthophosphoric acid by oxidation. The fusion of the substance is performed by the addition of 2 ml of concentrated sulfuric acid to — 100 mg of the substance. The black residue is then oxidized by a mixture of nitric acid and perchloric acid. The resulting orthophosphate can be determined at 8000 K by atom emission spectroscopy. The thermally excited phosphorus atoms emit a characteristic line at a wavelength of 178.23 nm. The extensity of the radiation is used for quantitative determination of the phosphorus content. 

The methods available for synthesis have advanced dramatically in the past half-century. Improvements have been made in selectivity of conditions, versatility of transformations, stereochemical control, and the efficiency of synthetic processes. The range of available reagents has expanded. Many reactions involve compounds of boron, silicon, sulfur, selenium, phosphorus, and tin. Catalysis, particularly by transition metal complexes, has also become a key part of organic synthesis. The mechanisms of catalytic reactions are characterized by catalytic cycles and require an understanding not only of the ultimate bond-forming and bond-breaking steps, but also of the mechanism for regeneration of the active catalytic species and the effect of products, by-products, and other reaction components in the catalytic cycle. 

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