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Estimating nutrient content of animal slurries using electrical conductivity

Published online by Cambridge University Press:  27 March 2009

R. J. Stevens
Affiliation:
Department of Agriculture for Northern Ireland, Agricultural and Environmental Science Division, Newforge Lane, Belfast BT9 5PX, UK The Queen's University, Department of Agricultural and Environmental Science, Newforge Lane, Belfast BT9 5PX, UK
C. J. O'bric
Affiliation:
The Queen's University, Department of Agricultural and Environmental Science, Newforge Lane, Belfast BT9 5PX, UK
O. T. Carton
Affiliation:
Teagasc, Agriculture and Food Development Authority, Johnstown Castle Research and Development Centre, Wexford, Ireland

Summary

Electrical conductivity was evaluated for estimating the nutrient content of cattle and pig slurries. Slurry samples were collected in 1991 from the storage tanks of 48 cattle and 10 pig units on commercial farms in Ireland. Samples were analysed for NH4+ and total concentrations of Na, K, Ca, Mg and P. Electrical conductivity (EC) was measured on raw slurries (ECraw) and on slurries diluted by 10 with water (ECdilute). Relationships between EC and nutrient content were examined by correlation and linear regression analyses.

In both slurry types, NH4+ was the dominant cation with K+ second in importance on a molar basis. Within each slurry type, the concentration of each of these cations was significantly correlated with EC. Using ECdilute gave more accurate predictions of concentrations than ECraw, but even ECraw was a better predictor than dry matter (DM) content. The linear relationships between NH4+ or K+ and ECdilute explained > 82% of the variance within each slurry type. The P content in slurries was related better to DM than to EC. Since EC measurement could be by cheap, robust meters, its potential for on-farm use deserves further investigation.

Type
Crops and Soils
Copyright
Copyright © Cambridge University Press 1995

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References

Bril, J. & Salomons, W. (1990). Chemical composition of animal manure: a modelling approach. Netherlands Journal of Agricultural Science 38, 333351.CrossRefGoogle Scholar
Chescheir, G. M. & Westerman, P. W. (1984). Rapid methods for determining fertiliser value of livestock manures. ASAE Paper No. 84–4082. Michigan: American Society of Agricultural Engineers.Google Scholar
Griffin, R. A. & Jurinak, J. J. (1973). Estimation of activity coefficients from the electrical conductivity of natural aquatic systems and soil extracts. Soil Science 116, 2630.CrossRefGoogle Scholar
Hem, J. D. (1982). Conductance: a collective measure of dissolved ions. In Water Analysis, Vol. 1, Inorganic Species, Part I (Eds Minear, R. A. & Lawrence, H. K.), pp. 137161. London: Academic Press.CrossRefGoogle Scholar
Japenga, J. & Harmsen, K. (1990). Determination of mass balances and ionic balances in animal manure. Netherlands Journal of Agricultural Science 38, 353367.CrossRefGoogle Scholar
Kjellerup, V. (1986). Agros nitrogen meter for estimation of ammonium nitrogen in slurry and liquid manure. In Efficient Land Use of Sludge and Manure (Eds Kofoed, A. Dam, Williams, J. H. & L'Hermite, P.), pp. 216223. London: Elsevier Applied Science.Google Scholar
McAllister, J. S. V. (1962). Investigations into the storage and use of slurry. 1. The nutrient content of slurry produced in Northern Ireland, 1962. Research and Experimental Record of the Ministry of Agriculture, Northern Ireland 12, 123133.Google Scholar
Ministry of Agriculture, Fisheries and Food (1986). The Analysis of Agricultural Materials. London: HMSO.Google Scholar
Payne, V. W. E. (1984). Specific conductance of wastewater as an indicator of nutrient content. ASAE Paper No. 844086. Michigan: American Society of Agricultural Engineers.Google Scholar
Smith, K. A. & Chambers, B. J. (1993). Utilizing the nitrogen content of organic manures on farms – problems and practical solutions. Soil Use and Management 9, 105112.CrossRefGoogle Scholar
Sposito, G. (1989). The Chemistry of Soils. New York: Oxford University Press.Google Scholar
Tunney, H. (1984). Slurry-meter for estimating dry matter and nutrient content of slurry. In Long-term Effects of Sewage Sludge and Farm Slurries Applications (Eds Williams, J. H., Guidi, G. & L'Hermite, P.), pp. 216233. London: Elsevier Applied Science.Google Scholar
Tunney, H. & Molloy, S. (1975). Variations between farms in N, P, K, Mg and dry matter composition of cattle, pig and poultry manures. Irish Journal of Agricultural Research 14, 7179.Google Scholar
Unwin, R. J., Pain, B. F. & Whinham, W. N. (1986). The effect of rate and time of application of nitrogen in cow slurry on grass cut for silage. Agricultural Wastes 15, 253268.CrossRefGoogle Scholar
Wallace, G. F. & Barrett, P. (1981). Analytical Methods Development for Inductively Coupled Plasma Spectrometry. Norwalk: Perkin Elmer Corporation.Google Scholar