Systems analysis of the effect of application methods on the entry of sulphur into pastures grazed by sheep.

Published online
01 Jan 1974
Content type
Journal article
Journal title
Journal of Applied Ecology

May, P. F. & Till, A. R. & Cumming, M. J.

Publication language


Quantitative estimates of the effects of different methods of S application on the entry of 35S into the grazed pasture system were made on an analogue computer. A model of a closed recycling system was used with least-squares methods to derive estimates of parameters associated with S entry via soil and plants. Model-generated behaviour was compared with observations on the specific radioactivity of wool following a single application of 35S to pasture in solid or liquid form with high and low levels of carrier sulphate. The results showed that a model based on a simple direct entry of S into the soil and plant was capable of fitting the experimental data for all methods of S application. However, the rate constants for the entry of S into soil and plant were affected by the form of S and the method of application used.

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