The map shows the estimated increase in biomass production that would be attainable if potential cropping intensities and commercial, market-oriented management practices were utilised.

The map shows the estimated increase in biomass production that would be attainable if potential cropping intensities and commercial, market-oriented management practices were utilised.
Photo: © LMU

Cropland’s untapped potential

The rising demand for food around the world can be met without expansion of agricultural cropland – provided the land now available is optimally exploited – says a new study by scientists in Germany.

In order to keep pace with projected rates of population growth, global agricultural production will have to be increased by 70 to 100 per cent over the next 35 years. Many research studies have concluded that this is a virtually impossible task. But a new study carried out by a team led by Professor Wolfram Mauser at the Department of Geography at Ludwigs-Maximilians University (LMU) in Munich/ Germany comes to a very different conclusion.

“The stock of agricultural land currently in use has the potential to feed this growing population, and even to exceed the projected demand for the year 2050. In other words, we could actually produce more than we will need,” says Mauser.

Crucially, the new study takes into account two important factors whose potential impact on crop yields has been neglected so far. First, the new work considers the potential impact of increased cropping intensity, i.e. production of more than one harvest annually. Secondly, in collaboration with economists in Professor Gernot Klepper’s group based at the Kiel Institute for the Global Economy (IfW) in Kiel, Germany, the LMU team estimated the degree to which yields could be enhanced if profit-maximising management practices, focusing on commercial production of crops for national and international markets, were adopted on a global scale.

Eightfold increase possible

Multiple harvests could increase yields by 39 per cent without expanding the land area devoted to agriculture. However, the new study estimates that adoption of a commercially oriented approach to land usage, in which crops are cultivated on current cropland at locations where they yield the highest profits, could boost this result by a further 30 per cent. The regions projected to have the greatest potential to benefit from such a step are Sub-Saharan Africa, Latin America, India and China.

If, in addition, one assumes that optimal agricultural practices appropriate for each major commercial crop are implemented on a global scale, a further increase of 80 per cent is feasible, according to the authors. This last estimate agrees with an earlier estimate by the UN Food and Agricultural Organization (FAO). Putting all of these factors together, the new study concludes that global crop yields could be enhanced relative to current figures by close to 150 per cent.

The authors themselves were surprised by the projected magnitude of the potential increase in crop yields. Thus, their study suggests that yields in Sub-Saharan Africa could be increased by up to eightfold. Moreover, significant increases are also attainable in Asia. “This latter result was unexpected, because agricultural land in India, for example, is already subject to highly intensive use. But, obviously, great potential lies in improving crop and farm management practices,” says Mauser.

(LMU/wi)

More information:

Nature Communications 2015, DOI: 10.1038/ncomms9946

More land, fewer harvests (09.18.2014)