Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Better water management could halve the global food gap

16.02.2016

Improved agricultural water management could halve the global food gap by 2050 and buffer some of the harmful climate change effects on crop yields. For the first time, scientists investigated systematically the worldwide potential to produce more food with the same amount of water by optimizing rain use and irrigation. They found the potential has previously been underestimated. Investing in crop water management could substantially reduce hunger while at the same time making up for population growth. However, putting the findings into practice would require specific local solutions, which remains a challenge.

“Smart water use can boost agricultural production – we’ve in fact been surprised to see such sizeable effects at the global level,” says lead-author Jonas Jägermeyr from the Potsdam Institute for Climate Impact Research. In a water management scenario the scientists call ambitious, global kilocalorie production could rise by 40 percent, while according to UN estimates roughly 80 percent would be needed to eradicate hunger by the middle of this century.


Drip irrigation. Photo: thinkstock

But even in less ambitious scenarios, results show that integrated crop water management could make a crucial contribution to filling the plates of the poor, says Jägermeyr. “It turns out that crop water management is a largely underrated approach to reduce undernourishment and increase climate resilience of smallholders.”

+++Large yield increase potential in China, Mexico, Australia+++

The scientists have run comprehensive biophysical computer simulations, constraining these in such a way that croplands do not expand into forests and no additional water resources are needed. As it is a global study, it provides detailed vegetation dynamics and water use effects in river basins – certainly too coarse to simulate farm-level conditions but suited to identify regional hotspots.

For example, the yield increase potential of crop water management is found to be particularly large in water-scarce regions such as in China, Australia, the western US, Mexico, and South Africa.

“Assessing the potential is tricky: If upstream farmers reroute otherwise wasted water to increase irrigation and production, less water returns to downstream users and consequently this can affect their production,” says co-author and team leader Dieter Gerten. “Below the line, we found that the overall production increases. Still, this of course poses quite some distributional challenges. Also, a lot of local government regulation and incentives such as-micro credit schemes are needed to put crop water management into large-scale practice.”

+++Mulching and drip systems to counter climate change impacts+++

The scientists took into account a number of very different concrete water management options, from low-tech solutions for smallholders to the industrial scale. Water harvesting by collecting excess rain run-off for instance in cisterns – for supplementary irrigation during dry spells – is a common traditional approach in some regions such as the Sahel region in Africa, but is under-used in many other semi-arid regions such as Asia and North America. Mulching is another option – the soil gets covered either simply with crop residues left on the field, reducing evaporation, or with huge plastic sheets. Finally, a major contribution to the global potential is upgrading irrigation to drip systems.

It is especially under ongoing climate change that water management becomes increasingly important to reduce food risks. The reason is that global warming is likely to increase droughts and change rainfall patterns, so water availability becomes even more critical than before. Assuming a moderate CO2 fertilization effect – plants take up CO2 and could hence benefit from higher concentrations in the air, but the magnitude of this effect is still under debate –, the study shows that in most climate policy scenarios water management can counterbalance a large part of the regional warming impacts on farming. Yet if greenhouse-gas emissions from burning fossil fuels are not reduced at all, in a business-as-usual scenario, water management will clearly not suffice to outweigh the negative climate effects.

+++Given the planetary boundaries, decision-makers should look into water use+++

”Water management is key for tackling the greater sustainability challenge,” says Wolfgang Lucht, co-author of the study and co-chair of PIK’s research domain Earth System Analysis. “It has been an issue in many local and regional studies and its effects on farm level have been well demonstrated, but on the global level it has been somewhat neglected. The renewed Sustainable Development Goals – while stipulating sustainable agriculture among all nations – need to be based on more evidence on how to achieve it; they do not focus on water use very much. Since we’re rapidly approaching planetary boundaries, our study should indeed draw the attention of decision-makers of all levels to the potential of integrated crop water management.”

Article: Jaegermeyr, J., Gerten, D., Schaphoff, S., Heinke, J., Lucht, W., Rockström, J. (2016): Integrated crop water management might sustainably halve the global food gap. Environmental Research Letters 11, 025002 [doi: 10.1088/1748-9326/11/2/025002]

Weblink to the article once it is published: http://iopscience.iop.org/article/10.1088/1748-9326/11/2/025002


For further information please contact:
PIK press office
Phone: +49 331 288 25 07
E-Mail: press@pik-potsdam.de
Twitter: @PIK_Climate

www.pik-potsdam.de

Jonas Viering | Potsdam-Institut für Klimafolgenforschung

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>