Changes over to 40%, 60% and even 100% organic farming can feed the world. Interestingly, this is only possible if we also do two things we’re supposed to do anyway. So what are these two crucial components of a truly sustainable diet, which would need to accompany organic farming?
It can sometimes seem fanciful to speculate on whether organic farming can feed the world, when so little of the land area of earth is farmed organically.
Nevertheless, a new study in Nature Communications, (Muller et al 2017) shows that it is possible to feed 10 billion humans using organic farming, albeit when accompanied with other changes.
However – and very importantly, these changes are necessary to carry out anyway. Primarily, they involved reduced meat consumption and a corollary decline in the area of land used to grow crops to feed animals; increased use of traditional methods of bringing Nitrogen into the farming systems (via clover and legumes) and reduced food waste.
This shift to organic production would reduce fossil fuel use, greenhouse gas emissions, Nitrogen related pollution and pesticide use. The guardian reported that “this is important, as converting other land such as forests, cerrado or peatlands to agricultural use would increase greenhouse gas emissions from the land.”
The main problem in a 100% shift to organic farming, the paper suggests, is guaranteeing an adequate supply of Nitrogen. This is only a problem at the very top end of their speculation – ie at over 80% conversion to organic farming – and not at issue at lower levels of conversion to organic. And, needless to say, we are some distance from 80% organic!
Nevertheless, even this problem is surmountable, with better regulation of food waste, including the potential integration of (composted) human food waste into the food system.
“Additional measures are needed to ensure adequate N-supply on croplands. Potential measures include optimizing legume management, recycling nutrients from various organic wastes and increasing nutrient use efficiency.”
It is also stated by the authors that increases below 100% in the overall organic land area, combined with necessary food system changes, are well capable of feeding the world and ensuring adequate Nitrogen supply:
“Overall, the results show that, for example, a food system with a combination of 60% organic production, 50% less food competing feed and 50% reduced food wastage would need little additional land and have an acceptable N-supply, when medium CC (climate change) impacts on yields are assumed.”
Similarly, even a partial conversion of 40% of the world’s farm land to organic, with various combinations of reduced crop growing for animal feed and reduced food waste are viable, involving in some cases reduced overall land use.
There are, nevertheless, problems with this study, some of which are acknowledged in the paper. With an absence of data in certain areas, they make questionable presumptions about organic farming.
For example, it lists a “10-20% increase in soil erosion under 100% organic conditions, because of increased land area farmed organically.” They further state that they are assuming similar soil erosion rates in organic and conventional farming.
This does not adequately take into account ample evidence for organic farming and soil building – both practical (e.g. using composted farm yard manure, using rotations, cover crops etc) and in the peer reviewed science, including meta studies of all available themed research. Neither does it contemplate improvements in organic techniques, including the potential adoption of the best regenerative techniques by increasing numbers of organic farmers. Indeed there are, inevitably, many improvements and refinements possible in organic not yet contemplated.
They also presumed a similar water demand for both systems, despite evidence that organic performs better under water stressed conditions, and did not have the capacity to model biodiversity into the study.
The potential for collapse of aspects of the food system under continuing present conditions, with for example pollinator population decline, is thus not considered.
They do make a presumption that full conversion to organic with the other two food system changes (reduced food waste and increased legume production/reduced meat consumption) would give an overall positive score for biodiversity.
Read the full paper:
Strategies for feeding the world more sustainably with organic agriculture
A version of this article has also appeared in the Irish Examiner farming