Nitrogen, in soil

Table 3 Effects of ploughing out of old permanent grassland at various dates. Estimated contribution in 1995 to nitrate-nitrogen in soil and, if leached, to the nitrate concentration in drainage from the soil (assumed to be 250 mm per year)...

K. Mengel, Turnover of organic nitrogen in soils and its availability to crops. Plant Soil 7S/ 83 (1996). 

P. C. Brookes, L. Landman, and D. S. Jenkin.son, Chloroform fumigation and the release of soil nitrogen a rapid extraction method to measure microbial biomass nitrogen in soil. Soil Biol. Biochem. 17331 (1985). 

E. S. Jensen, Mineralization-immobilization of nitrogen in. soil amended with low C N ratio plant residues with different particle sizes. Soil Biol. Biochem. 26 519 (1994). 

As the one of the main end products of protein metabolism in living organisms, urea is a primary source of organic nitrogen in soil (from animal urine, fertilizers, etc.). Monitoring the level of urea is important for medicine, as well as for environmental protection. Urease is an enzyme that breaks the carbon-nitrogen bond of amides to form carbon dioxide, ammonia and water. This enzyme is widely used for determination of urea in... 

Jenkinson DS (1990) The turnover of organic carbon and nitrogen in soil. Phil Trans Royal Soc Series B 329 361-368... 

Rice CW, Moorman TB, Beare M (1996) Role of Microbial Biomass Carbon and Nitrogen in Soil Quality. SSSA Special Pub 49 203-216... 

In other titrations, the component to be titrated is separated from soil and subsequently titrated. The simplest of these is the determination of soil ammonia. However, all forms of nitrogen in soil are important, so methods of converting other nitrogen-containing compounds to ammonia, distilling it, and determining its concentration by titration are important. 

Nitrogen in soil organic matter is mostly found in proteins and amino acids. Although the specific analysis for these important and interesting compounds... 

This technique has found very limited applications in soil and sediment analysis and is particularly useful when routine automated analyses at the mg L 1 level of large numbers of samples is required. The technique has been applied to the determination of total phosphorus, total organic carbon and total nitrogen in soils, total organic carbon in non-saline sediments and total sulphur in saline sediments. 

Nelson and Sommers [44] have described a Kjeldahl digestion procedure for the determination of total nitrogen in soils in which the sample is digested with sulphuric acid using a selenium catalyst. The digest is steam distilled with sodium hydroxide and ammonia titrated with 3.5mM sulphuric acid. Various other workers have discussed the application of Kjeldahl digestion to the determination of total nitrogen in soils [45-47]. 

Table 12.7 Determination of nitrate- plus nitrate-nitrogen in soil after extraction by manual and automatic techniques... 

The Kjeldahl digestion-titration technique [44] discussed in section 12.5.1.1 for the determination of total nitrogen in soils has been applied to the determination of total nitrogen in sediments. 

HMSO (1979) Method 57. Nitrogen in Soil. The Analysis of Agricultural Materials. RB 427, 2nd edn., London. 

The Analysis of Agricultural Materials, 2nd edn, R.B. 427. HMSO, London, (1979) Method 2, p. 6. Preparation of Samples of soil Method 8, p. 21. Boron, water soluble in soil Method 57, p. 134. Nitrogen in soil Method 62, p. 148. Organic matter in soil Method 63, p. 151. Particle size distribution in soil... 

Many fertilizers are based on ammonia compounds. Modem agriculture requires more nitrogen in soils than is normally replaced by the nitrogen cycle, hghtning, decaying plants and animals, and other natural means... 

Hook JE (1983) Movement of phosphates and nitrogen in soils following apphcation of municipal wastewater. In Nielson DW, Elrik DE, Tanji KK (eds) Chemical mobility and reactivity in soil system. Soil Sci Soc Am Spec Publ 11 241-255... 

The analysis of soils and plant material are common examples used to demonstrate ICP applications. Dahlquist and Knoll(43) compared the preparation and ICP analyses of botanicals (16 elements) and soils (11 elements) with few exceptions the ICP values for the CII botanicals were in excellent agreement with the assigned values, and the soil analyses were in excellent agreement with FAA analyses of soil digests. )ones( 4) reported the analysis of 17 elements in plant material and soils but confirmation of the two analyses was not given. Alder, et. aJ.(75) describe the unique analysis of ammonia-nitrogen in soils by gas evolution into an ICP no interferences were observed from the concomitants evaluated and acceptable recoveries were obtained. Irons et. al.(76) compared the ICP analyses of 13 elements in NBS orchard leaves and bovine liver to the data obtained by FAA and energy dispersive x-ray. 

Brand W (2002) Mass spectrometer hardware for analyzing stable isotope ratios. In P de Groot (ed.) Handbook of stable isotope analytical techniques. Elsevier, Amsterdam Brandriss ME, O Neil JR, Edlund MB, Stoermer EF (1998) Oxygen isotope fractionation between diatomaceous silica and water. Geochim Cosmochim Acta 62 1119-1125 Bremner JM, Keeney DR (1966) Determination and isotope ratio analysis of different forms of nitrogen in soils. III. Soil Sci Soc Am Proc 30 577-582 Brenninkmeijer CAM (1993) Measurement of the abundance of CO in the atmosphere and the and 0/ 0 ratio of atmospheric CO with applications in New Zealand and Australia. J Geophys Res 98 10595-10614... 

Figure 4.2 Concentration of nitrogen in soils subjected to different concentrations of tylosin.

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