Posts Tagged ‘food security’

Special journal issue “Feeding 9 billion by 2050: challenges and opportunities”

16/04/2015 2 comments

In its April edition, the journal ‘Food Security’ presents a series of papers presented at an OECD meeting on “Feeding 9 billion by 2050: challenges and opportunities”.

The articles cover a range of topics related to future food security, ranging from general outlooks over the debate of sustainable intensification to water, the role of fish, or the impact of soil degradation.

Graph of the year 2013: Proportion of calories delivered as food

Although already well into 2014, here is my personal “Graph of the Year 2013”: The proportion of produced calories that are delivered to the food system.


Source: Cassidy et al., Environm. Res. Lett. 8 (2013) 034015

The figure is one output of a study carried out by Emily Cassidy and colleagues of the University of Minnesota that was published in the journal Environmental Research Letters.

The researchers approach the challenge to provide sufficient amounts of food amidst global population growth, increased biofuel production and changing dietary preferences from a different angle than is widely done. Instead of estimating the increases in farm prodution necessary to satisfy the rising needs for agricultural products they analyze the current allocation of the world’s crop production to different uses.

According to the study, only 55% of global calorie production is directly used for human consumption. The remaining 45% serve either as animal feed or other uses such as industrial purposes and biofuels. In consequence, 41% of all calories produced are lost from the global food system. While the crops grown on one hectare could satisfy the caloric needs of 10 people, currently only 6 people are fed.

The graph gives a global overview of the fraction of the calories delivered to the food system per calories produced.  It shows that the losses from the food system are highest where livestock production, industrial uses and biofuels production are of a high importance. These are mainly the most affluent regions (e.g. North America, Europe), but also the regions in which agriculture is oriented at the production of animal feed for the global market (e.g. Eastern South America).

The arguably most important conclusion from the analysis is that if the crop calories used for feed and other uses were shifted to direct human consumption, up to around 4 billion more people could be fed. Or, perhaps easier to achieve, already small changes in the allocation of crops to animal feed and biofuels could significantly increase global food availability.


Livestock and global change: Special feature in PNAS

Is a fertilizer revolution the right recipe for African agriculture?

It is often argued that to increase its farm yields and close its yield gap, Africa needs a new Green Revolution, based on the expanded use of fertilizer. An intriguing analysis by Pablo Tittonell of Wageningen University, however, tells a somewhat different story (find it on p.17ff. in Tittonell’s inaugural lecture at WUR.

In an on-farm research program carried out in Western Kenya, Tittonell and others compared maize yields on the fields of 60 households under different management regimes. A part of the plots was managed by the farmers themselves, with or without use of fertilizers. Another part was managed by researchers without the use of fertilizers, only taking care of the right planting time and plant spacing, frequent weeding, and using certified local cultivars. A third part of the plots was managed by the researchers with the use of N-P-K fertilizers.


Source: Taken from Tittonell (2013).

The figure shows the striking result that the plots managed by researchers even without fertilizers had higher yields than the plots managed by the farmers, thus illustrating the potential of proper agronomic management. In particular with rising distance from the homestead this potential is high.

On the other hand, the figure also shows that N-P-K fertilization has an even higher potential for increasing yields. However, the researchers also argue that, given the current quality of the road network, bringing the amounts of fertilizers required to obtain significant yield increases at scale to the rural communities would not be feasible .

The analysis raises a number of interesting questions. The overarching question is – taking optimized agronomic management and the use of higher amounts of N-P-K fertilizers as alternatives – what is the better alternative?

Read more…

Losses in the food chain – from field to household consumption

At the website of GRID-Arendal, Hugo Ahlenius presents a graph which shows the proportion of food energy produced on the fields actually arrives at the consumers: Of 4600 kcal produced only 2000 kcal are actually consumed. The remaining 2600 kcal are lost during harvest, distribution and in particular through the conversion to meat and dairy (1200 kcal).

Losses in the food chain

Losses in the food chain

Presenting responses to the environmental food crisis, a report by the UNEP elaborates more on the role of dietary change.

2012 Global Food Policy Report

The International Food Policy Institute (IFPRI) has just released its 2012 Global Food Policy Report.

Watch the introductory video:

Is going by bike better than being vegetarian?

Being vegetarian is perhaps one of the best lifestyle choices you can make. And one of the strongest argument for making this choice perhaps is that, depending on the type of meat and the production system it comes from, 1 food calorie from meat need by between 2 to 10 times more energy (I don’t know the exact numbers, but they are somewhere out there) than one from a plant based diet.

Not surprising that I was delighted to find the link to economz – visualizing your carbon footprint on the Food Tank website. economz is a visualization project with a very nice online tool which allows you to compose alternative meals from different popular food items and visualize the carbon foodprint of those meals in terms of car miles traveled.

Now, if I prepare a meal consisting of a steak with french fries and some tomatoes and broccoli (for the vitamins!) I learn that eating this dish once a day for one year corresponds to 3794 miles driven by car. Wow! A more reasonable and vegetarian dish with tofu, rice, broccoli and tomatoes is worth 1087 miles. This means that in this scenario going vegetarian (only for lunch) would safe me 2707 miles per year. That’s indeed very nice.

But well, I think again and what comes to my mind is that many people actually use their car a lot more every year and in fact those 2707 miles might not be that much. I have no idea about the average annual car use in a more or less developed society. But I can take my own daily commuting as a reference, which is around 15 miles. Assuming that I do all this by car at the moment (which I don’t), I would need to leave the car at home and take the bike on 180 days of the year to save the additional emissions from a steak-and-chips diet. That is substantial, and my tentative conclusion is that being vegetarian is about as good as going to work by bike during 75% of the year. More or less…