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Optimising slurry application timings to minimise nitrogen losses: OPTI-N - ES0115

Description
The overall objective of the project is to develop practical slurry application timing strategies to minimise nitrogen (N) losses to the air and water environments. Replicated field scale experiments will be carried out on four commercial farms covering a range of livestock and cropping systems, soil and climatic conditions. Ammonia, nitrous oxide and nitrate leaching losses will be measured from contrasting improved technology slurry (bandspread/shallow injection) application timings. The effects of the contrasting application timing strategies on different N loss pathways (i.e. N ‘pollution swapping’) will be quantified. We anticipate that the slurry application timings made in close synchrony with active crop growth will result in lower overall N emissions to the air and water environments, although the balance of emissions may change. The fertiliser nitrogen replacement value of the slurry applications will be measured to quantify effects of the contrasting timings on crop N recovery. Also, the effects of the different slurry application timings on grass silage quality will be assessed at three of the sites. This information will be important in developing and promoting practical slurry application timing strategies that reduce nitrogen losses to the wider environment, and for the validation of models such as MANNER and NGAUGE.

The results from this project will assist DEFRA in achieving its key role of implementing the EU Directive on Integrated Pollution Prevention and Control, the EU National Ceilings Directive arising from the EU Acidification Strategy, N protocol of the UNECE Convention on Long-Range Transboundary Air Pollutants, EU Nitrates Directive, EU Water Framework Directive and the Kyoto Protocol for reducing greenhouse gas emissions. The work also supports DEFRAs policy objectives of protecting and improving the environment by limiting nitrogen losses from agricultural land, and improving the utilisation of nitrogen from farm manures as part of sustainable farming systems.
Objective

The overall objective of the project is to develop practical slurry application timing strategies to minimise nitrogen losses to the air and water environments.

In more detail, the study objectives are:

1. To quantify the effects of contrasting bandspread/shallow injected slurry application timings on ammonia and nitrous oxide emissions from arable and grassland soils.
2. To quantify nitrate leaching losses following autumn-winter bandspread/shallow injected slurry applications on arable and grassland soils.
3. To quantify the effect of bandspread/shallow injected slurry application timings on slurry fertiliser N replacement values and crop yields and quality.
4. To develop slurry application timing guidelines to minimise N losses to the air and water environments and to maximise crop N recovery.

Project Documents
• Final Report : OPTI-N Final Report   (4854k)
Time-Scale and Cost
From: 2002

To: 2006

Cost: £881,587
Contractor / Funded Organisations
ADAS UK Ltd.
Keywords
Air Pollution              
Ammonia              
Climate Change              
Environmental Protection              
Nitrates              
Pollution              
Water Pollution