Article contents
On the Question whether Nitrites or Nitrates are produced by non-bacterial processes in the Soil
Published online by Cambridge University Press: 27 March 2009
Extract
The experiments described in the following pages were made with a view to discover how far purely physical and chemical processes, known to take place in the soil, may be expected to give rise to nitrites and nitrates. Scattered throughout the extensive literature on nitrification are occasional papers tending to show, what might also be expected on theoretical grounds, that non-bacterial processes may be important sources of nitrates. Formerly these processes were considered to be the only sources, then came the brilliant researches of Schloesing and Muntz, Warington, Winogradsky, and others on nitrifying organisms, and non-bacterial processes were forced into the background. Now that a full knowledge of the various sources of nitrogen compounds in the soil has become so indispensable to the agriculturist, it seemed desirable to make a careful examination of the various chemical and physical processes known to take place in the soil, and to ascertain whether they make any direct or indirect contribution to its stores of nitrates. To this end we have repeated and extended such of the recorded observations bearing on the subject as seemed to merit repetition; we have also devised other experiments to make the examination as complete as possible.
- Type
- Research Article
- Information
- Copyright
- Copyright © Cambridge University Press 1906
References
page 445 note 1 We use the expression “induced oxidation” in preference to “autoxidation” to denote the acceleration of the rate of oxidation of one substance brought about by the simultaneous oxidation of another.
page 445 note 2 Annalen Chem. u. Pharm. 1862, 124, 1.Google Scholar
page 445 note 3 The Griess-Ilosvay test for nitrous acid was introduced in 1879.
page 445 note 4 Among the former were Böhlig (Ann. Chem. Pharm. 1863, 125, 21);Google Scholar Carius (ibid. 1874, 174, 31); Weith, and Weber, (Berichte 1874, 7, 1745);Google ScholarWarington, (Journ. Chem. Soc. 1881, 39, 229),CrossRefGoogle ScholarBaumann, (Landw. Versuchs. Stat. 1888, 217);Google ScholarNeumann, , Chem. Centr. 1890, 665);Google Scholaron the other hand, Zabelin, (Ann. Chem. Pharm. 1864, 130, 82)Google Scholarv., Loesicke, Arch. Pharm. 1879 [3] 14, 58;Google ScholarScheurer-Kestner, (Bull. Soc. Chem. 1883; [2]39, 289);Google Scholar and Schaer, (Arch. Pharm. 1905, 243, 198) supported Schönbein's contention.CrossRefGoogle Scholar
page 446 note 1 The reagent consists of two solutions, (a) 1 grm. of sulphanilic acid (C6H4NH3SO3H) is dissolved in 14.7 grams of glacial acetic acid and 285 c.c. water. This is best done by warming the sulphanilic acid with the acetic acid, to which an equal bulk of water has been added. The remaining water must be added carefully. (b) 0.2 gram of a naphthylamine is dissolved in 14.7 grams of glacial acetic acid and 325 c.c. water, taking the same precautions as before. The two solutions are kept separate. 1 c.c. of each is added to the liquid under examination.
page 446 note 2 Physikalische Zeitschrift, 1902, 3, 574Google Scholar: see also Ebert and Ewers, ibid. 4, 162.
page 447 note 1 Ber. 1890, 23, 1443.CrossRefGoogle Scholar
page 448 note 1 Chem. Zeit. 1903, 27, 149.Google Scholar
page 448 note 2 Landw. Versuchs. Stat. 1904, 60, 103.Google Scholar
page 448 note 3 For nitrates we used the phenol sulphonic acid test as modified by Wiley, and found it worked admirably. Mix 15 grams of phenol with 92.5 c.c. of sulphuric acid and 7.5 c.c. of water and digest on the water-bath. The solution to be examined is evaporated to dryness on the water-bath, 1 c.c. of the reagent is added, then 1 c.c. of water, the whole warmed and allowed to stand for 15 minutes. It is then diluted to 25 c.c. and made alkaline with ammonia, when a yellow colour appears.
page 448 note 4 Landw. Versuchs. Stat. 18, 452.Google Scholar
page 448 note 5 Trans. Chem. Soc. 1881, 371.
page 449 note 1 This Journal, Part 3, p. 261.
page 449 note 2 Amer. Chem. Journ. 1903, 29, 236Google Scholar
page 450 note 1 Cf. Berthelot, , Ann. de Chimie, 1877 [5] 12, 440.Google Scholar
page 450 note 2 Cf. Berthelot, , Comptes Rendus, 1889, 108, 543.Google Scholar The idea that ammonia is produced when moist iron and zinc are allowed to stand in air was commonly held at one time, see Gmelin's, Handbook, Vol. 2, p. 417.Google Scholar
page 451 note 1 Collard de Martigny (Journ. de Chimie Médicale, 1827, III. 517Google Scholar) was one of the first to make the experiment in this way.
page 451 note 2 Landw. Versuchs. Stat. 1904, 60, 103.Google Scholar
page 451 note 3 This was secured by placing in the apparatus a small dish of concentrated ammonia solution, which was renewed from time to time.
- 1
- Cited by
