SAIN project findings were presented at Royal Society meeting

Professor David Powlson of SAIN Working Group 1 was invited to speak at Royal Society meeting, "Reducing greenhouse gas emissions from agriculture: meeting the challenges of food security and climate change", held on 28th February - 1st March 2011 in London. The title of Prof Powlson's speech was "Greenhouse gas emissions associated with nitrogen fertiliser - lessons from a situation of nitrogen excess in China". The abstract of the speech is as following:

China is responsible for the manufacture and use of over 30% of the worlds nitrogen(N) fertiliser and at least 30% of global nitrous oxide(N2O) emissions. There is clear evidence that the country has "overshot" the quantity of fertiliser N required to maximise crop production and that rates applied to major grain crops could be decreased by at least 30% with no yield penalty. Greater reductions are possible for horticultural crops. N fertiliser carries a significant greenhouse gas （GHG) cost - in part from carbon dioxide (CO2) emissions from fertiliser manufacture and in part from N2O emissions, both direct and indirect, when applied to soil. Total emissions (manufacturing, transport, direct and indirect losses from soil) are estimated at about 12t CO2 - equivalent per t N. Evidence indicates that much of the N2O is from nitrification rather than denitrification, suggesting that nitrification inhibitors could be effective in reducing agricultural emissions. Other techniques such as deep placement of fertiliser and use of urease inhibitors may increase N use efficiency and decrease ammonia volatilisation which is presumed to be a major contributor to indirect N2O emissions. A conservative estimate is that annual agricultural GHG emissions in China are in the range 1200 - 1400 Mt CO2 - equivalent, representing about 20% of total emissions from all sectors. N fertiliser is extimated to account for at least 32% of agricultural emissions. Reducing N use by 30% would deliver a GHG emissions reduction equivalent to at least 2% of China's total emissions from all sources, in addition to numerous other benifits. To achieve this, more effective methods of delivering information to farmers are essential as are policy changes to remove incentives for the over-production and over-application of N fertiliser.

Click the following link for more information about the Royal Society meeting: http://royalsociety.org/events/reducing-greenhouse-gas/