The Role of Soil Organic Matter and Manures in Sustainable Nutrient Cycling - Sustainable Management of Soil Organic Matter - page 284

conceptual models used can make comparisons problematic (Watson and
Atkinson, 1999). A standardized approach is required in order to compare
different farming systems appropriately, and the reliability and limitations
of the data need to be acknowledged. An approach which combines nutri-
ent budgets and soil measurements, along with other measurements such as
economic performance, may increase the reliability of such comparisons.
Acknowledgements
This work is funded by the UK Ministry of Agriculture, Fisheries and
Food. IACR-Rothamsted also acknowledges the grant-aided support of the
Biotechnology and Biological Sciences Research Council.
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