It is
possible to feed more than 9 billion people with organic production methods
with a small increase in the required crop acreage and with decreased
greenhouse gas emission. But this assumes considerable reduction in food
wastage and in the quantities of feed grown to animals.
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| Picture: Ann-Helen Meyer von Bremen |
The research
builds on assumptions of a 25% reduction in yield with organic methods, the
continued increase in global population up to more than 9 billion 2050 as well
as different scenarios of impact of climate change on agriculture yields. The
model doesn’t assume any change in the area used for grazing. The researchers
acknowledge that different research show big variation in the ”yield gap”
between organic and conventional. It is primarily research from Europe that shows
big yield gaps, while other studies show much smaller gaps, if any. In general
their assumptions are conservative and could hardly be accused of being biased
in favour of organic.
Obviously, if
consumption patterns are equal and yields are lower and population increases, more
land would be needed with a large-scale conversion to organic agriculture. But if
food waste is reduced with 50% and this is combined with a 50% reduction in the
use of human-edible crops as animal feed, less land would be used compared to a
reference scenario (the assumed population, consumption and production as per
2050 in FAO:s analysis) – still more than today though.
The biggest
agronomic challenge for such a large scale conversion to organic would be the
supply of nitrogen. On the up-side of that, the reactive nitrogen overload of
the whole biosphere, one of the biggest changes in local and global biological
cycles, would be reduced and gradually disappear. The researchers acknowledge
that recycling of human waste and food waste into the agriculture system could
reduce the nitrogen deficiency in agriculture, but they have not included that
in the model.
The
exclusion of synthetic fertilizers leads to big reductions of greenhouse gas
emissions, as both the use and production of nitrogen fertilizers are major
causes for emissions. Emissions from ruminants (cows, sheep and goats) will
increase somewhat as their total numbers will increase (but less than the
increase of population). Similarly, the greenhouse gas emissions from rice
cultivation will increase because of more rice being produced.
The
combination of the lower yields and the increase of leguminous plants (beans
etc) in order to fix nitrogen makes the availability of animal feed lower. So
the decreased use of human-edible crops as feed for animals is rather a
production necessity than something triggered by consumption changes. The
reduction of animals will mainly be for monogastric animals such as pigs and
chicken as they are the ones that mainly eat human-edible crops.
The results
of the study coincides with similar results on a national and regional level.
For instance, researchers
from the Nordic countries concluded that it would be possible to feed
between 31 and 37 million people (compared to the current 26 million) in the
Nordic countries with organically produced food assuming substantial reduction
in meat consumption.
One can claim
that the results also show that you can’t convert the agriculture system to
organic without increasing the cultivated lands considerably. Because, despite
the conclusions of the authors, that is also a result from their scenarios. If
nothing else is changed land demand will increase with 33%.
Ultimately,
all this modelling and scenario-building has limited value and the results are
very much fixed by the assumptions and input data. The food system is a dynamic
system where you can’t change just one or two parameters and keep the rest the
same. But models and scenarios can still help us to identify certain critical
conditions.
The choice
of the authors to change food wastage and the proportion of food fed to animals
is a rather reasonable choice and not taken out of the blue. One can assume
that food will become more expensive with a large-scale conversion to organic
and that will reduce waste considerably. Similarly, using human-edible food as
feed for animals will be less interesting from a commercial perspective when they
become more expensive. The
dramatic increase of consumption of pig and chicken meat is as much a result of
cheap grains and soy beans as of consumer demand. The increased consumption of pulses to
compensate for the reduction of meat coincide with a need to increase the
cultivation of such crops to adjust to nitrogen shortages.
There are
also other assumptions that could be included in models. The total calories
produced under the scenarios are far above what people need to eat and as
obesity is now a big global problem, one could have reduced calories available
and thus be able to show even better results AND an improved health status of
the world’s population. Improvements in the utilization of grasslands could
also have been a parameter to consider.
Finally,
the economic feedback loops are very important. There are several ways to
increase yields in agriculture, of which the use of chemical fertilizers and
pesticides are just two. They are admittedly important, but one can increase
productivity by deploying more work, other nature resources (e.g. water), by
switching crops or taking more crops per year. What is done is mainly determined
by economic factors. Very few farms, organic or non-organic, produce at their
maximum, but they produce what is optimal given prices of factors of production
and output prices. In most cases, production per person has been much more
important that production per unit of land. But in a world with limited land
resources and 9 billion people, this will sooner or later change.
So yes, we
can. If we want to.
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