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

More articles from Earth Sciences:

nachricht NASA finds newly formed tropical storm lan over open waters
17.10.2017 | NASA/Goddard Space Flight Center

nachricht The melting ice makes the sea around Greenland less saline
16.10.2017 | Aarhus University

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Researchers release the brakes on the immune system

18.10.2017 | Health and Medicine

Separating methane and CO2 will become more efficient

18.10.2017 | Life Sciences

Ocean atmosphere rife with microbes

17.10.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>