What changes will need to be made to agricultural practices in order to double food production for predicted population growth this century?

WHO: Jonathan A. Foley, Kate A. Brauman, Emily S. Cassidy, James S. Gerber, Matt Johnston, Nathaniel D. Mueller, Christine O’Connell, Deepak K. Ray, Paul C. West, John Sheehan, Institute on the Environment (IonE), University of Minnesota, Saint Paul, Minnesota, USA
Navin Ramankutty, Department of Geography and Global Environmental and Climate Change Centre, McGill University, Montreal, Quebec, Canada
Christian Balzer, Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, California, USA
Elena M. Bennett, School of Environment and Department of Natural Resource Sciences, McGill University, Montreal, Quebec, Canada
Stephen R. Carpenter, Center for Limnology, University of Wisconsin, Madison, Wisconsin, USA
Jason Hill, Institute on the Environment (IonE), University of Minnesota, Department of Bioproducts and Biosystems Engineering, University of Minnesota, Saint Paul, Minnesota, USA
Chad Monfreda, Consortium for Science, Policy and Outcomes (CSPO), Arizona State University, Tempe, Arizona, USA
Stephen Polasky, Institute on the Environment (IonE), University of Minnesota, Department of Applied Economics, University of Minnesota, Saint Paul, Minnesota, USA
Johan Rockström, Stockholm Resilience Centre, Stockholm University, Stockholm, Sweden
Stefan Siebert, Institute of Crop Science and Resource Conservation, University of Bonn, Bonn, Germany
David Tilman, Institute on the Environment (IonE), University of Minnesota, Department of Ecology, Evolution& Behavior, University of Minnesota, Saint Paul, Minnesota, USA
David P. M. Zaks, Centre for Sustainability and the Global Environment (SAGE), University of Wisconsin, Madison, Wisconsin, USA

WHAT: Looking at all of the recent research on agricultural processes and working out how we can feed 9 billion people without also cooking the climate

WHEN: 20 October 2011

WHERE: Nature, Vol. 478, October 2011

TITLE: Solutions for a cultivated planet (subs req.)

Currently, 1 in 8 people globally lack access to food or are chronically malnourished. This alone is a large problem for world food systems, however with the population expected to increase to 9 billion by 2050 the problem just got even bigger. Our agricultural food systems are estimated to require doubling in order to feed all those extra people.

How will agricultural food systems have to change this century to provide global food security while also reducing the environmental impacts that agricultural practices have caused leading to increasing climate change?

This is the question these researchers set out to answer in another wonderful example of science being a collaborative sport.

Agriculture currently uses 50% of the earth’s ice-free surfaces. 12% is used for crops we eat directly, while 38% is used for pasture to grow livestock as well as other things like biofuels (2%). We as a species have used pretty much all the land that is available on the planet for agriculture – the land we haven’t farmed is tundra, desert, mountains or cities. Agriculture is the single biggest land use on the planet.

Innovation is going to be the major key to increasing global food production in this century, given that there’s not much more land we can farm on effectively. Global crop yields increased by 56% between 1965-1985 with the advent of mechanised and industrialised agricultural practices. However, between 1985-2005 yields only increased by a further 20%, and yields are increasing by smaller margins each year.

The four major solutions this group of researchers came up with to feed the world sustainably were:

1. Ending Agricultural Geographical Expansion

Most of the land currently being cleared for new agriculture is in the tropics and contributing to tropical deforestation. This is an issue for two reasons: firstly because deforestation worldwide is a huge contributor to greenhouse gas emissions and climate change, but also secondly because most tropical land is less productive than land that is already being farmed. This means that the productivity gained is less than the greenhouse gasses emitted through the deforestation.

Luckily for the authors of the paper, one of the major drivers of tropical deforestation is local economic drivers, which means the solution to this issue is socio-economic and this group of scientists will leave that for the economists.

2. Closing Yield Gaps

Recent research has looked at ‘yield gaps’ which is where different farms in the same area with the same soil and climate conditions end up with different crop yields. Closing those yield gaps and making sure each farm is as productive as possible is one gap that could contribute greatly to feeding the world. The research shows the greatest room for improvement is in areas of Africa, Latin America and Eastern Europe.

Closing the yield gap by 95% (so that your farm is 95% as productive as your neighbour’s farm) could increase world food production by 58%. If we only managed to close the yield gap by 75%, there would still be a 28% increase in food production.

However, doing this while simultaneously reducing the environmental impacts from intensive agriculture requires farmers to look more at Precision Agriculture methods.

3. Increased Efficiency

The current agricultural usage of water, nutrients and chemicals is unsustainable. Excess nutrient use has affected Nitrogen and Phosphorus cycles which has led to farmland without enough soil nutrients because of losses in the agricultural processes and deadzones in oceans from too much nutrient runoff.

The research found that nutrient excesses were worst in areas of China, Northern India, the USA and Western Europe, and recommends that these countries implement nutrient recycling and recovery programs to minimise use.

4. Food Delivery Systems

Food delivery systems need to be reformed in order to feed 9 billion people. The paper points out that a dietary shift away from meat would make land much more productive as it would be growing crops for direct human consumption, but they’re also realistic about how unlikely it is that we’ll all become vegetarian.

However there are much more immediate efficiencies to be found reducing waste in supply chains. The UN Food and Agriculture Organisation estimates that 1/3 of all food is never consumed. It either gets damaged in transit, or is not sold and gets thrown out. Making our supply chains from farm to table shorter and more efficient will be key to feeding the world.

The researchers point out that feeding 9 billion people successfully will only be possible if all of the above strategies are implemented at once. Better yields and food delivery systems won’t be very useful if deforestation continues and climate change starts wiping out all the yield gains. Similarly, ending deforestation alone won’t be very useful if water and nutrient use don’t become more efficient and yields are affected by shortages.

The paper suggests scaling up some solutions that are already being implemented by some farmers like precision agriculture, drip irrigation, organic soil remedies (like no-till farming), buffer strips and wetland restoration in low lying areas, drought resistant crops and low fertilizer crops, perennial grains and paying farmers for environmental services.

As with combating climate change, feeding the world is going to take new and innovative practices which not only improve the farming business, but also improve the resilience of agricultural food systems, and all of these solutions need to be tried simultaneously. But I guess no-one ever said solving the world’s problems was going to be easy!