Organic as a Platform for Ecological Innovation in Agriculture

By Emma Bryce

It is estimated that agriculture contributes to around 25% of annual greenhouse gas emissions worldwide. As the climate becomes more erratic, changing weather patterns and rising temperatures are bringing into focus how agricultural practices can both help and hinder global warming, and how organic agriculture fits into the equation.

Just under half of those emissions are the result of land-use change, or the clearing of natural vegetation to make way for farmland that would otherwise be storing carbon dioxide. The other half of those emissions are related to farming practices themselves, such the release of nitrous oxide as a result of fertilizer use and methane production from livestock, and the fossil fuels used in production inputs.

While many proponents tout organic agriculture as the key to shifting food production in a more sustainable direction, critics point to a reduction in yield as the largest hurdle standing in the way of this goal. A recent study in Nature Communications analyzed how transitioning from conventional to organic farming practices would impact greenhouse gas emissions. While the study found that organic practice would reduce the climate pollution and emissions produced from conventional farming practices directly, it states that the reduced yield potential of organic systems (up to 40% less yield) meaning that it requires more land to produce the same amount of food, resulting in more land clearing and ultimately leading to greater emissions overall.

The Rodale Institute disagrees with this analysis and has conducted their own meta-analysis comparing conventional and organic farming systems in North America, with data showing that there is no statistical difference in yield between the two systems after comparing them over a 40 year period. In fact, while there is no statistical yield difference in years with average climatic conditions, in climate change scenarios, like years of drought, organic systems have been shown to have 30% greater yields than their conventional counterparts. Comparing conventional to organic systems is not straightforward due to the complex nature of organic production systems,  including crop rotations, varied soil building practices, livestock integration, and a host of other ecosystem benefits and services.

The key issue that many studies detracting from organic agriculture fail to recognize is the sequestration potential of healthy soils and the role of biodiversity in healthy agroecological systems. A study published in Agriculture, Ecosystems and the Environment found that when using certain best management practices, organic farming is able to bolster the soil’s carbon sequestration potential by 18% and increase soil microbial biomass carbon by an average of 30%. The most influential best management practices on overall soil health include using organic soil amendments, conservation tillage, and the use of cover crops. The study found that using best practices, especially in relation to soil amendments, can boost soil carbon sequestration potential by an average of 24%.

Organic farming has been shown to have greater ecological benefits compared to conventional practices, including reduced pesticide use and exposure, a decrease in eutrophication, enhanced biodiversity, reduced consumption of non-renewable resources, and a potential increase in carbon sequestration potential for well-managed soils. The combined ecosystem services produced by organic agriculture need to be accounted for. Focusing solely on GHG emissions rather than looking at ecosystem services as a whole would be short-sighted and irresponsible. The all-or-nothing argument for organic agriculture is potentially misleading and distracting. Context- and site-specific evaluations would allow for a better understanding of where organic production is more appropriate and effective in addressing GHG emissions and where it may not be.

What this highlights is the need for more research concerning the sequestration potential of organic soils, as well as the overall efficiency of complex diversified farming systems and the additional ecosystem services they provide.