Hostname: page-component-78c5997874-s2hrs Total loading time: 0 Render date: 2024-11-03T05:28:49.652Z Has data issue: false hasContentIssue false
  • English
  • Français

The Organic matter in heavy alkaline soils

Published online by Cambridge University Press:  27 March 2009

A. F. Joseph  and
B. W. Whitfeild
Get access Rights & Permissions [Opens in a new window]

Extract

1. Sudan soils are very low in organic matter, the total organic carbon being usually less than 1 per cent. In the Gezira, the humus carbon is about 40 per cent, of that of the total.

2. Humus preparations purified as far as possible could not be obtained ash-free. Specimens of humus from widely different sources contain nearly the same proportion of carbon.

3. Humus solutions (in very dilute alkali) keep fairly well in the dark. They also keep in bright sunlight if air is excluded. The use of standard solutions for colorimetric purposes is justified if not kept too long.

4. Field studies show that the humus content of good soil is greater than that of poor, and that there is a marked inverse connection between salt and humus content.

5. The above conclusion does not apply to the depth distribution of these constituents. In the Gezira, the maximum humus content is found at the fourth foot and the maximum salt content is found at about the same depth.

6. The total nitrogen content of the soils studied is low, usually about 0·03 per cent. About one-fifth of this is humus nitrogen, and the carbon-nitrogen ratio is about twelve to one.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 17 , Issue 1 , January 1927 , pp. 1 - 11
Copyright
Copyright © Cambridge University Press 1927

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

(1)Waynick, D. D. (1919). A Simplified Wet Combustion Method for the Determination of Carbon in Soils. Journ. Indust. and Eng. Chem. 11, 643.Google Scholar
(2)Beam, W. (1912 and 1913). The Determination of Humus in Heavy Soils. Cairo Scient. Journ. 6, 93 and 7, 219.Google Scholar
(3)Eden, T. (1924). A Note on the Colorimetric Estimation of Humic Matter in Mineral Soils. Journ. Agric. Sci. 14, 469.CrossRefGoogle Scholar
(4)Snyder, H. (1897). The Composition of Humus. Journ. Amer. Chem. Soc. 19, 738.CrossRefGoogle Scholar
(5)Cameron, F. K. and Breazeale, J. F.The Organic Matter in Soils and Subsoils. Journ. Amer. Chem. Soc. 26, 29.CrossRefGoogle Scholar
(6)Martin, F. J. and Massey, R. E. (1923). Nitrification in Sudan Soils. Wellcome Tropical Research Laboratories, Khartoum, Publication No. 29.Google Scholar
(7)Osborne, T. B. (1907). The Vegetable Proteins. Page 49. London, Longmans, Green & Co.Google Scholar
(8)Joseph, A. F. (1925). Alkali Investigations in the Sudan. Journ. Agric. Sci. 15, 407.CrossRefGoogle Scholar
(9)Russell, E. J. (1921). Soil Conditions and Plant Growth. Page 335. London, Longmans, Green & Co.Google Scholar
(10)Russell, E. J. (1921). Soil Conditions and Plant Growth. page 176.Google Scholar
(11)Shantz, H. L. and Marbut, C. F. (1923). The Vegetation and Soils of Africa. Page 218. American Geographical Society Research Series No. 13, New York.Google Scholar
(12)Hall, T. D. (1921). Nitrification in Some South African Soils. Soil Science, 12, 301.CrossRefGoogle Scholar
(13)Bal, D. V. (1925). The Determination of Nitrogen in Heavy Indian Soils. Journ. Agric. Sci. 15, page 454.CrossRefGoogle Scholar