Soil Organic Matter Management: The Roles of Residue Quality in C Sequestration and N Supply - Sustainable Management of Soil Organic Matter - page 141

Reduced tillage reduced mineral N losses to drains, but, on this soil
type, it also resulted in a larger requirement for fertilizer N after ploughing
out of long-term grass swards. No-tillage and deep ploughing retained more
carbon than conventional ploughing. However, there were large losses of
nitrogen as nitrous oxide from no-tillage and, initially, significant losses
of nitrate from deep ploughing. Thus, deeper ploughing than normal is
likely to be a better option for C and N conservation than no-tillage.
Experimental responses to treatments were strongly influenced by
climatic and topographical variability.
Acknowledgements
We are grateful to the many colleagues who helped with this experimental
work, especially Robert Ritchie for his efficient management of the field
experiment and Rab Howard and Frances Wright for collection and analy-
sis of water samples. Funding for this project was provided by SOAEFD.
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