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Diurnal variation in nitrous oxide fluxes and impact on agricultural emission factors - CC0232

Description
Nitrous oxide emissions from agriculture are making a significant contribution to greenhouse gas effects and there are a number of ongoing exercises which are contributing to the construction of robust inventories of the contributions of various components of agriculture. This is required in order that policies can be developed to enable the recently agreed targets for reduction of greenhouse gas emissions can be met. One of the major problems associated with nitrous oxide is the extent of spatial and temporal variability which occurs. A contributory factor to the temporal effects is a recently demonstrated diurnal change in N20 emissions. Most measurements of emissions are based on a single short exposure period (usually c. 1h), which, depending upon when it was taken can impose a considerable bias and inaccuracy when this is expressed on a 24h basis. The present project aims to quantify this effect so that correction factors can be applied to current emission factors and a more accurate assessment of agricultural contributions can be made. This will then provide a sounder basis on which to develop future policies.
Objective
The objectives are as follows:
1. To confirm and quantify the diurnal variability in N2O fluxes in a range of agricultural managements and crops.
2. To determine effects at different times of the year.
3. To determine effects on key characteristic soil types.
4. To develop a simple model description to allow the derivation of correction factors.
5. To demonstrate effects of applied corrections on N2O emissions on agricultural soils.
Project Documents
• Final Report : Diurnal variation in nitrous oxide fluxes and impact on agricultural emission factors   (74k)
• Final Report - Annex : Diurnal variation in nitrous oxide fluxes and impact on agricultural emission factors - Table   (896k)
Time-Scale and Cost
From: 1998

To: 2001

Cost: £219,242
Contractor / Funded Organisations
Institute of Grassland and Environment Research (IGER)
Keywords
Climate and Weather              
Climate Change              
Environmental Protection              
Greenhouse Effect              
Sustainable Production              
Fields of Study
Agriculture and Climate Change