Phosphorus compounds, soils

Mortland, M.M. and Gieseking, J.E. (1952) The influence of clay minerals on the enzymatic hydrolysis of organic phosphorus compounds. Soil Science Society of America Proceedings 15, 10-13. 

PHOSPHORUS (In Biological Systems). Phosphorus is required by every living plant and animal cell. Deficiencies of available phosphorus in soils are a major cause of limited crop production, Phosphorus deficiency is probably the most critical mineral deficiency in grazing livestock. Phosphorus, as orthophosphate or as the phosphoric acid ester of organic compounds, has many functions in the animal body. As such, phosphorus is an essential dietary nutrient. 

Phosphorus containing fertilizers Phosphates are the basic substances in these fertilizers. Phosphorus is also essential for plants. Phosphorus compounds are produced by powdering rock phosphate and adding sulfuric acid to it. The resulting products - phosphoric acid and calcium salts (from the rock) are directly applied to the soil to increase its phosphorus content. Potassium fertilizers examples Potassium chloride, Potassium nitrate etc. A complete fertilizer contains nitrogen, phosphorus and potassium in a fixed ratio. This is called NPK fertilizer. 

Fertilizers are compounds or mixtures usually used to supply potassium, nitrogen, and phosphorus to soil. If a bag of fertilizer consists of almost pure KNO3 (potassium nitrate), what percentages of those three important elements should appear on the label ... 

M. A. Adams and L. T. Byrne (1989). 31P NMR analysis of phosphorus compounds in extracts of surface soils from selected karri (Eucalyptus diversicolor f. Muell.) forest. Soil Biol. Biochem., 21, 523-528. 

Modern, high-yield agriculture is dependent on regular fertilization with phosphorus compounds that are either immediately soluble in the soil solution or become soluble at a rate sufficient to supply the crop. A factor to contend with in phosphate fertilization is soil... 

In 2008, more than 95 percent of all the phosphate rock mined in the United States was used in the manufacture of fertilizer and animal feed supplements. Modern farmers use enormous amounts of synthetic (artificial) fertilizer on their crops. This synthetic fertilizer contains nitrogen, phosphorus, and potassium, the three elements critical to growing plants. These elements normally occur in the soil, but may not be present in large enough amounts. Adding them by means of synthetic fertilizer helps plants grow better. Most farmers add some form of synthetic fertilizer to their fields every year. This demand for synthetic fertilizers accounts for the major use of phosphorus compounds. 

Because plants need nitrogen compounds, potassium compounds, and phosphorus compounds to grow, these are often added to the soil as fertilizers. Potassium sulfate, which is used to make fertilizers, is made industrially by reacting potassium chloride with sulfur dioxide gas, oxygen gas, and water. Hydrochloric acid is formed with the potassium sulfate. 

Organic phosphorus compounds, primarily inositolhexaphosphates (probably more than 50% of all organic phosphates), occiu in soils. The parent cyclic polyol, inositol, exists in numerous stereoisomeric configurations, of which myo-, scyllo-, neo-, and cZZ-inositol have been isolated from soils as phosphate esters. The hexaphosphate of myoinositol (myo-IHP), phytic acid, occurs in plant tissues. It often occurs as phytin, the calcium magnesium salt. Esters of myo-IHP are readily adsorbed in acidic soil solution by clay minerals and finely divided hydrated oxides of iron and aluminum. Organic sulfur compounds present in soils probably occur primarily as amino acids—e.g., cysteine, cystine, and methionine. 

Enzymatic reactions can be used as a means of both characterizing and releasing classes of organic phosphorus present in waters, soils and sediments. For example, phosphate monoesters can be quantified by the use of a phosphomonoesterase such as alkaline phosphatase. Alternately, the high specificity of some enzymes for particular substrates can be used as the basis for determination of specific organic phosphorus compounds, or as part of a post-separation quantification step. 

Fig. 1.5. High-performance liquid chromatographic separation of phosphorus compounds determined in soil leachate using a strong anion exchange stationary phase. Reprinted from Espinosa etal. (1999) with permission from the American Society of Agronomy.

Preconcentration and separation of trace phosphorus compounds in soil leachate. Journal of Environmental Quality 28, 1497-1504. 

Turner, B.L., Mahieu, N. and Condron, L.M. (2003) Phosphorus-31 nuclear magnetic resonance spectral assignments of phosphorus compounds in soi I NaOH-EDTA extracts. Soil Science Society of America Journal 67, 497-510. 

NMR spectroscopy was first used on soil extracts by Newman and Tate (1980), and since then has advanced our knowledge of organic phosphorus in soils and environmental samples more than any other technique. Phosphorus NMR spectroscopy may be used on solid or extracted samples, with the advantage that all phosphorus species in a sample can be characterized simultaneously without the need for complex cleanup and chromatographic separation procedures. However, the heterogeneous physical and chemical properties of soils, relatively low phosphorus concentrations, and the natural association of phosphorus with paramagnetic ions such as iron and manganese, make P NMR analysis of soil samples more complicated than studies of purified compounds. Phosphorus NMR experiments on environmental samples... 

Makarov, M.l. (1998) Organic phosphorus compounds in alpine soils of the northwestern Caucasus. Eurasian Soil Science 31, 778-786. 

Makarov, M.L, Haumaier, L., Zech, W. and Malysheva, T.l. (2004) Organic phosphorus compounds in particle-size fractions of mountain soils in the northwest Caucasus. Geoderma 118, 101-114. 

In the experiments where added organic phosphorus substrates are present, their low adsorption on soil constituents makes the comparison with natural organic phosphorus compounds unrealistic (Findenegg and Nelemans, 1993 Joner et al., 2000). 

Inositol phosphates are often the most abundant organic phosphorus compounds in soils, although they are less common in aquatic samples. They include a sequence of phosphate monoesters, from inositol hexa-kisphosphate to inositol monophosphate (Mandal and Islam, 1979 Harrison, 1987), in various stereoisomeric configurations [myo, scyllo, neo, B-cbiro) of the sugar inositol (Anderson and Malcolm, 1974 Anderson et al., 1974 Cosgrove, 1980 Harrison, 1987 Turner et al, 2002). These compounds are... 

In aquatic environments, substantial amounts of inositol phosphates have been reported in lake waters (McKelvie et ah, 1995) and estuarine sediments (Suzumura and Kamatani, 1995). Other more labile organic phosphorus compounds, such as phosphate diesters and adenosine triphosphate, which account for only a small proportion of the total organic phosphorus in soils, are particularly important in lake and marine sediments (Carman et ah, 2000), as are labile polyphosphates (Hupfer et ah, 1995). 

Besides naturally occurring organic phosphorus compounds, the soil organic phosphorus concentration can be increased by manure and slurry application and, to a lesser extent, by the use of phosphorus-containing pesticides. Many soils receive animal manure, in which typical phosphorus concentrations are many times... 

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