Organic Farming and Climate Change
Much is claimed about the impacts of organic farming on climate change, both positive and negative – the evidence is mixed and a real understanding depends on looking in more depth at the impacts of specific organic management practices on key components of climate change. This session compared the emissions and energy efficiency of organic farming and conventional systems, and looked at how the damaging greenhouse gases of methane and nitrous oxide can be reduced within agriculture. The key issue of carbon sequestration was also touched upon, and the difficulties with making accurate predictions in this field.
Nic Lampkin began the session with a presentation on how organic farming and climate change interact, stating that a careful assessment of evidence is required, but that real world data is highly variable. There is a risk, therefore, of basing policy on unreliable evidence. However, Professor Lampkin did provide examples of studies which demonstrated that organic farming uses less energy and is more efficient than conventional in terms of input/output, and a lack of fertilisers/pesticides accounts for a large part of this difference.
Jamie Newbold, from IBERS then gave a presentation on methane production from animal agriculture, highlighting that although ruminants contribute a significant amount towards global emissions, the fact that they are efficient convertors of grassland should not be forgotten. In the correct situation ruminants can therefore add to food security.
Dr. Christine Watson from SAC followed with a presentation on whether organic farming is sequestering carbon dioxide. Dr. Watson referred to a number of trials which demonstrated that conventional systems produced less organic matter and soil carbon than organic although added that it is difficult to make comparisons, as a range of methods have been used to measure carbon sequestration. Dr. Watson then gave a presentation on N2O emissions from organic farming, pointing out that wetter soils produce more N2O, and that highest N2O emissions come from land that was in clover the previous year. Dr. Watson also highlighted the importance of mitigation methods being cost effective. In the following debate it was highlighted that ‘zero-carbon’ is a difficult concept to quantify, as living is a ‘leaky process’.
It was also stated that organic farming’s best argument is not that we are better in terms of climate change. In terms of adaption to climate change, it was highlighted that the UK is already a climate gradient – we therefore already know how to cope with a range of climate measures and adaption is about applying this knowledge.
- Andreas Fliessbach's Presentation Slides
- Jamie Newbold's Presentation Slides
- Nic Lampkin's Presentation Slides
- Christine Watson's Presentation Slides