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The assessment of structure in tropical soils

Published online by Cambridge University Press:  27 March 2009

H. C. Pereira
Affiliation:
East African Agriculture and Forestry Research Organization

Extract

A comparison of methods of measuring the structural condition of cultivated surface soil was made for two important East African soil types.

The soil samples were drawn from two field experiments: (i) a tillage trial in coffee on a porous red lateritic clay soil of recent volcanic origin; (ii) a rotation trial for cotton, on a red sandy lateritic loam of granitic origin.

Of the measurements on soil cores, total porespace and field capacity (⅓ atmosphere) showed little change, while percolation rates, free-draining pore-space and a new rainfall acceptance test all reflected the observed field behaviour of the soils, and showed fairly close and highly significant correlation. Field sieving of dry clods gave highly significant differences in the lateritic clay, the stronger clods indicating the poorer soil condition. Drysieving for ½ mm. crumb was ineffective, as was wet-sieving after wetting under vacuum. Wetting by immersion gave some differences between treatments, but higher variability and no significant correlation with free-draining pore-space. Wetting by rainfall impact on dry crumbs gave the best wet-sieving tests on the clay soil. Different sieving techniques gave inconsistent results on the sandy soil. Crumb structure measurements are not efficient indications of structural conditions on these soil types, which are of wide occurrence in tropical countries.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1955

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References

REFERENCES

Coile, T. S. (1936). Soil Sci. 42, 139.CrossRefGoogle Scholar
Colman, E. A. (1947). Soil Sci. 63, 277.CrossRefGoogle Scholar
Dortignac, E. J. (1950). Soil Sci. 69, 95.CrossRefGoogle Scholar
Griffith, ap G. (1950). Uganda Dep. Agric. Record of Investigations, no. 1, 68.Google Scholar
Hardy, F. (1933). Emp. J. Exp. Agric. 1, 102.Google Scholar
Hursh, C. R. & Hoover, M. D. (1942). Proc. Soil Sci. Soc. Amer. 6, 414.CrossRefGoogle Scholar
Jamison, V. C. & Reed, I. F. (1949). Soil Sci. 67, 311.CrossRefGoogle Scholar
Keen, B. A. (1933). Emp. J. Exp. Agric. 1, 97.Google Scholar
Low, A. J. (1950). Trans. 4th Int. Soil Sci. Congr. III.Google Scholar
Low, A. J. (1954). J. Soil Sci. 5, 57.CrossRefGoogle Scholar
Lutz, J. F. (1947). Soil Sci. 64, 399.CrossRefGoogle Scholar
Martin, W. S. (1944). Emp. J. Exp. Agric. 12, 21.Google Scholar
McCalla, T. M. (1942). Proc. Soil Sci. Soc. Amer. 7, 209.CrossRefGoogle Scholar
Pereira, H. C. (1955). J. Soil Sci. (in the Press).Google Scholar
Pereira, H. C. & Beckley, V. R. S. (1952). Emp. J. Exp. Agric. 21, 1.Google Scholar
Pereira, H. C. & Jones, P. A. (1954 a). Emp. J. Exp. Agric. 22, 231.Google Scholar
Pereira, H. C. & Jones, P. A. (1954 b). Emp. J. Exp. Agric. 22, 23.Google Scholar
Pereira, H. C., Chenery, E. M. & Mills, W. R. (1954). Emp. J. Exp. Agric. 22, 148.Google Scholar
Reeve, R. C. (1953). Proc. Soil Sci. Soc. Amer. 17, 324.CrossRefGoogle Scholar
Richards, L. A. & Weaver, L. R. (1943). Soil Sci. 56, 331.CrossRefGoogle Scholar
Russell, E. W. (1938). Tech. Commun. Bur. Soil. Sci., Harpenden, no. 37.Google Scholar
Russell, E. W. & Tamhane, R. V. (1940). J. Agric. Sci. 30, 210.CrossRefGoogle Scholar
Slater, C. S. & Hopp, H. (1951). Agron. J. 43, 1.CrossRefGoogle Scholar
Smith, R. M. & Browning, D. R. (1946). Soil Sci. 62, 243.CrossRefGoogle Scholar
Smith, R. M. & Cernuda, C. F. (1951). Soil Sci. 71, 337.CrossRefGoogle Scholar
Swanson, C. L. W. (1950). Agron. J. 42, 447.CrossRefGoogle Scholar
Walkley, A. & Black, I. A. (1934). Soil Sci. 37, 29.CrossRefGoogle Scholar
Zwerman, P. J., Page, J. B. & Yoder, R. E. (1953). Proc. Soil Sci. Soc. Amer. 17, 159.CrossRefGoogle Scholar