05 Apr 2010

Out of the Demographic Trap: Hope for Feeding the World

In Africa and elsewhere, burgeoning population growth threatens to overwhelm already over-stretched food supply systems. But the next agricultural revolution needs to get local — and must start to see rising populations as potentially part of the solution.
By fred pearce

I bring good news from Machakos, a rural district of Kenya, a couple of hours drive from Nairobi. Seventy years ago, British colonial scientists dismissed the treeless eroding hillsides of Machakos as “an appalling example” of environmental degradation that they blamed on the “multiplication” of the “natives.” The Akamba had exceeded the carrying capacity of their land and were “rapidly drifting to a state of hopeless and miserable poverty and their land to a parched desert of rocks, stones and sand.”

Since independence in 1963, the Akamba’s population has more than doubled. Meanwhile, farm output has risen tenfold. Yet there are also more trees, and soil erosion is much reduced. The Akamba still use simple farming techniques on their small family plots. But today they are producing so much food that when I visited, they were selling vegetables and milk in Nairobi, mangoes and oranges to the Middle East, avocadoes to France, and green beans to Britain.

What made the difference? People. They made this transformation by utilizing their growing population to dig terraces, capture rainwater, plant trees, raise animals that provide manure, and introduce more labor-intensive but higher-value crops like vegetables. For them, “multiplication” of their numbers has been the solution rather than the problem. They have sprung the demographic trap.

The story of Machakos convinces me that humanity is not done yet — our ingenuity may still save us from succumbing to planetary limits, and we can feed a growing world population.

For most of human existence, the land appeared limitless. Whenever populations grew too large for comfort, societies occupied new land. But by the 1960s, most of the best land was taken and the frontiers were being
We know we can feed 10 billion people, because we are already growing enough.”
pushed up inhospitable mountainsides onto poorer soils, and into the last tropical rainforests.

“The battle to feed all of humanity is over,” Paul Ehrlich famously declared in his 1968 book, The Population Bomb, in which he predicted widespread famine because of overpopulation.

But human ingenuity stepped in. In the past half century, thanks to the “green revolution,” the world has added just 10 percent to farmland but more than doubled food production.

What next? The world was brought up short in 2008 by soaring food prices on international markets. Politicians were unnerved as food riots broke out in more than a dozen countries. Prospect magazine headlined “The Return of Malthus.” We may now be able to feed nearly 7 billion people. But world population is expected to reach 9 or 10 billion later this century. Can we feed them all?

Pessimists have a point. We are undermining agriculture by damaging water and soils. We use more than half of the world’s river flows each year, mostly to irrigate crops. We are recklessly mining irreplaceable underground water reserves. By some estimates, a third of the world’s fields are losing soil faster than natural processes can create it. And now comes the threat of climate change.

But bleak though the figures are, they are no worse than those in the 1960s. Just as then, they reveal not natural limits but the current limits of our competence, both political and technical. Feeding the world in the 21st century requires doing things dramatically better.

The “green revolution” is still keeping pace with population. The trouble is that consumption of grain is growing faster, driven by the world’s growing appetite for biofuels and for meat and dairy products. Of the two billion tons of grain grown around the world, less than half is eaten directly by people.

Paradoxically, this is good news, says U.S. demographer Joel Cohen. “We know we can feed 10 billion people, because we are already growing enough — if they have a vegetarian diet.” The real threat is consumption patterns, not “overpopulation.” But at least we know the world can be fed.

A second cause for optimism is that farm yields in most of the world are a small fraction of the potential using existing seeds. Africans typically grow
The next agricultural revolution needs to help poor farming communities manage their soils better.
one ton of grain on a hectare, Asians grow three tons and Europeans and North Americans upwards of five tons. Futurologist Jesse Ausubel of Rockefeller University in New York says that “if during the next 50 years or so, the world’s farmers reached the average yield of today’s U.S. corn grower, ten billion could be fed with only half of today’s cropland, while they eat today’s U.S. calories.”

That may be far-fetched. But the flipside of our reckless management of water and soils is that we could do things so much better. Conservation farming has vast potential to protect soils. And simple drip irrigation systems could halve global water use by farmers. It’s not rocket science. It’s just tubes with holes in.

Of course, it is one thing to ensure there is enough food on the global dinner table, but quite another to make sure everyone has a seat at the table. Subsistence farming communities make up the majority of the world’s hungry. It matters little to them whether the global grain warehouses are full if their village granaries are empty.

The next agricultural revolution needs to get local. It needs to help these poor farming communities find ways to manage their own soils better by using livestock to fertilize soils, conserving rainwater in case of drought, breeding and exchanging local crop varieties, and finding natural predators for troublesome pests.

In particular we are talking about Africa. Malthusian thinking holds sway here. Many would agree with British demographic doomster Maurice King of Leeds University, who argues in an editorial he co-authored that “large parts of sub-Saharan Africa are demographically trapped... committed to a future of starvation and slaughter.”

But such pessimism is dangerous. It echoes the Malthusian fatalism that the British used to excuse their inaction during the Irish potato famine a
Demography may help drive communities to crisis, but it does not define how they respond.
century and a half ago: “nothing to be done... too many people... brought it on themselves... better let the carnage play out.”

More importantly, the idea of overpopulated Africa simply is not true. The continent contains 11 of the world’s 20 least-densely populated nations and only one of the 20 most densely populated. Africa’s problem is bad agriculture, not too many people.

Robert Watson, chair of the UN’s International Assessment of Agricultural Knowledge, Science and Technology for Development, which reported in 2008, says of Africa: “Today’s hunger can be addressed with today’s technology. It’s not a technical challenge, it’s a rural development challenge. Farm yields across the continent can be raised from a typical one ton per hectare to four or five tons.”

It can be done. Good news is not hard to find in Africa. And often — as in Machakos — it is more people, not fewer, that can be the key.

Machakos is certainly not unique. In the highlands of western Kenya, the Luo people showed me how they were replacing their fields of maize with a landscape richer both commercially and ecologically. They had planted woodlands that produced timber, honey, and medicinal trees. I saw napier grass, once regarded as a roadside weed, sold as feed for cattle kept to provide milk and manure.


The Other Inconvenient Truth:
The Crisis in Global Land Use

Land Use
As the international community focuses on climate change as the great challenge of our era, it is ignoring another looming problem — the global crisis in land use. With agricultural practices already causing massive ecological impact, the world must now find new ways to feed its burgeoning population and launch a “Greener” Revolution.
In West Africa, Dutch geographer Chris Reij has charted a similar revival since the famines of the 1970s. Again, he says, it is labor-intensive management of the land that often holds the key. “The idea that population pressure inevitably leads to increased land degradation is a much repeated myth,” he says. “It does not. Innovation is common in regions where there is high population pressure. This is not surprising. Farmers have to adapt to survive.”

There will be exceptions — distressing situations where farmers are unable to rescue their declining environments, and places where fast-rising populations trigger a dangerous tailspin of decline, and where land disputes, war, and bad government leaves communities incapable of harnessing their human resources. But to suggest that Africa is doomed is a dangerous lie. Demography may help drive communities to crisis, but it does not define how they respond.

And as with Africa, so perhaps with the planet. I bring good news: human ingenuity. Rising populations may bring more mouths to feed, but they also bring more hands to work and brains to think. We are not done yet.


Fred Pearce is a freelance author and journalist based in the UK. He is environment consultant for New Scientist magazine and author of the recent books When The Rivers Run Dry and With Speed and Violence. His latest book, The Coming Population Crash and Our Planet’s Surprising Future, will be published this month. In earlier articles for Yale Environment 360 Pearce has written about the demographics of overpopulation and the threat posed by overconsumption on the planet.

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Your article is more balanced than the old cornucopian arguments of Julian Simon -- though the last paragraph bids fair to channel "The Ultimate Resource" -- but I counsel even more nuance here.

The question is not "Can the world feed X billion people at a basic level of subsistence?" but rather "Can the world feed X billion people with a satisfying material quality of life, one that provides enough food security to enable people to achieve aspirations that don't threaten the continued existence of all life of on earth?" In the sense of the second question, the world is already vastly overpopulated: by well-fed Americans like me (especially so) but also by people from all economic strata in all regions.

I have yet to see a convincing argument (including ones that purport to show a dire collapse of social structure by an aging, below-replacement population) that refutes the idea that a gradual attrition from current population levels, in every region of the world, would be a benefit, both socially and environmentally.

Posted by Dave Harmon on 05 Apr 2010

The problem with the human endeavor is not that we are evil, or wrong, or stupid, or irresponsible, but that our endeavor is so concentrated, so intensive, and so unabashed in its pursuits without the requisite capability of encompassing it all. It's too much of us.

Think about our evolution. For millions of years we had no idea what was going on. We had no language, no imagination, and then developed rudimentary forms of both and started to carve out tools, and mix pigments, and paint on walls, depicting what we saw in our mind's eye. But we are not used to this. Life here, is not used to what we do. We've been with civilization for 5,000+ years, and we expect to get it all right.

We've been with modern civilization as we know it for less than a century, with billions of people, an insurmountable flow of goods and information, an unprecedented influx of techonological wizardry when barely ten thousand years ago we were just starting to accidentally experiment with plant types and crops, and not knowing what the hell we were doing? Evolution takes time. Of species, of societies, of the mind, and of the heart. But we move so quickly we can't catch up with ourselves. By the time we've seen what we've done it's too late and we're not entirely sure what we've done in the first place. We live and we learn, yes, and that's part of the human experience, but we're at a point were we have little leeway to screw up.

Our imaginations have no boundaries, no worries of consequence, no challenge to overcome. But when we take our dreams and bring them out here, we have to find ways to reconcile our fantasy with reality. It'll be some time before we're any good at that.

Posted by Mustang on 05 Apr 2010

So... More hands make light work. Does this mean that we'll be so much better off when our population has doubled to 14 billion? Perhaps we should target 28 billion; then, oh surely then, our work load will be light indeed!

Let us posit that the planet can, with ideal management systems in place, support 28 billion and that we can find the energy and food to provide a high-tech lifestyle to all. OK, now tell me why? Why would we choose a population size of 28 billion? What, precisely, is the object of maximizing our number?

Posted by OldStone50 on 07 Apr 2010

All the benign policy improvements which Fred sketches in here could be done by a global
population half, a quarter, a tenth, a hundredth, a ten-thousandth of what it is now, with equally good effect for human society, and with the added bonus that our one and only overall life-support system -- "...Earth's beauty-dress, her life-robe...." (Ted Hughes: 'October Salmon' in 'River'), the unstressed global wilderness, would be much less damaged than it is today.

Reading Fred's output from time to time, I'm starting to suspect that he's an incorrigible
technowhizz cornucopian (still believe in growthforever, do you Fred?) who is still able to
believe, in the face of the growing and already massive tidal wave of evidence to the contrary,
that everything at least +could+ be for the best in this best of all possible worlds: Pangloss on
steroids. I wish I could believe that he's right, really I do. But I don't.

The reality -- I intuit -- is that the Earth is already carrying an inherently unsustainable
population overshoot of humans -- a bloom -- and that our numbers -- as with any bloom --
are bound to crash. We are simply not exempt just because, well, you know, we're Homo
Sapiens +Sapiens+ so move over Gaia and make room for the new master!

Ha! As if!

Our creative resourcefulness for a while longer, whilst there are still some niches of possibility
left to stuff just a bit tighter, might stave off the general global holocaust for a bit more time,
whilst we continue to add yet more humans to the bloom. But my uncomfortable instinct is that that is just going to make the crash even more horrific, when it finally overwhelms us.

And anyway, the +fact+ is that over my whole lifetime (70 years) and longer the holocaust has already been happening anyway, and continues right now: literally hundreds of millions living in wretched poverty and dying early and horribly. The comfortable techno-fantisising of us members of the Pampered Twenty Percent, in our redoubts of insulated and blinkered
privilege, has done nothing -- literally zero -- to alter that reality to any significant degree. Nor is there any slightest sign now that we're about to amend our ways radically.

What's going to happen, I suspect, is that the net relation between global birth rate and death
rate is going to reverse quietly; and then the now-negative gap will increase in fits and starts,
as the global dieoff of our human overshoot population gets going.

This is going to happen to us as fate. As Dmitry Orlov says, control of our numbers and of the
circumstance which keep four-fifths of us in poverty, was never within our control whilst our
numbers were on the way up, and there's not the slightest reason to think that we shall be
able to control the situation when they're crashing down again.

We have some further evolution to do yet, before we can get to that state of competence --
if ever.

Posted by Rhisiart Gwilym on 07 Apr 2010

I wish the article had explained how Machakos produced the miracle it did. The rest of the world seems, intractably, to be on the opposite path, toward disintegration and chaos. And crises multiply through global and human systems that are dysfunctional. There are countless good examples like Machakos, yet, the global monster of inappropriate governance outpaces and drowns them on a worldwide level.

I don't know how Machakos managed its transformation (apart from growing its population, which is clearly not, by itself, a formula for improved governance). It's critical to know, so as to discern whether or how their success could be extrapolated to the bigger picture. Meanwhile, we all just seem to be flailing around.

Given the power of the USA to effect global change (good or bad), I would start here. What are we doing to help ourselves live sustainably and set the pattern for the rest of the world to follow? We have a system of government that is deadlocked. We have rising inequality, an overheated media, a loss of democracy, all-devouring agri-business, and fractured programs, good or bad, which don't portend to shared endeavor, to common purpose.

I have been thinking that it requires a gigantic, evolutionary initiative by the international community, led by the USA, to switch from the train track toward planetary holocaust to one that puts us on a more sustainable path. I didn't see this path as one in which population growth would be encouraged, but I take the point that there are way to use already large population for general benefit. This is an existential moment, where we simply act in the most enlightened way we can think of, test the results, and adjust our actions accordingly.

Maybe there's a beneficial way to "sop up" Mexico's large immigrant population to do massive, well coordinated work projects that help both communities toward that more sustainable path.

Posted by Trevor Burrowes on 07 Apr 2010

Dear Dr. Pangloss:

This kind of fuzzy feel good thinking is the final death knell for the planet. People are the problem, not their customs and institutions. In civilized societies we voluntarily limit reproduction, primarily through education, women's liberation, and the vitiating effects of ennui. Those not so constrained need to be controlled by coercive methods if necessary. The alternative is famine and war, nothing new to history, but more pernicious than ever given the available tools and already exhausted state of the biosphere. The Rwandan genocide is the wave of the future, a poster child for the consequences of cornucopeian thinking and a prelude to the night of long knives when we will all join in the cannibal feast. The bottom line is that Malthus was right and you are horribly wrong.

Posted by Bruce Morgan on 08 Apr 2010

Yes, good points. We can feed the world on people power, sans gmos and their chemical kin.

I wish the author had gotten a bit more specific on what the innovations we need look like, though. One way it looks is agroforestry, the interplanting of shade/fodder shrubs with food crops, which is a system talented at boosting yields while building local water tables. The Heifer project is doing this in Sierra Leone, Ghana, and Cameroon, and others are piloting it elsewhere.

Such permaculture-type systems are also not necessarily 'labor intensive.' They take care and attention from people, but growing food this way is simple and elegant, and does not conjure the same visions as do endless digging and plowing.

Orion Grassroots Network

Posted by Erik Hoffner on 08 Apr 2010

Machakos sounds like a great idea; it should be replicated elsewhere. Is it the answer to feeding 10 billion people? I doubt it. Cities in Africa - as elsewhere - are already overcrowded with unemployed people bombarded by the media with temptations to eat more meat, drive cars, have better homes, live the life we do here. Better farming methods will help those still on the land but isn't going to solve this drive to have more.

We shouldn't be distracted from efforts to solve population increase and environmental disaster.

Posted by Lawrence Sunderland on 08 Apr 2010

This article raises many good points but misses one major one: nitrogen (N) fertilizers are not even mentioned. N fertilizer drives increasing yields in agricultural systems more than any other variable, yet only 50 percent of what is applied ends up in the plant. The rest ends up elsewhere - air, soil, and water - often with serious ecological consequences. These effects are manageable, and Africa uses far too little N now, but no food system improvements will happen without N.

Posted by Michael Beman on 08 Apr 2010

The Green Revolution will die with the dwindling reserves of cheap oil. Nature will cull the excess humans in areas that can’t grow their own food without oil based fertilisers.

Whatever fertile land that is left in places like Africa will be taken over by big corporations to grow crops for the production of bio fuel. The lives of Africans will grow cheaper as oil prices rise.

Ronnie Wright

Posted by Ronnie Wright on 08 Apr 2010


I looked at the web site, found it intriguing and left a comment.

The problem I have with your analysis is that the dire conditions you forecast are happening too slowly or too far away to galvanize people to change. And if you're saying, never mind, breakdown will occur nonetheless, just wait and see, that is not an ethical position to take.

The destruction of the planet is a moral failure, and you don't resolve it by suspending morality. We'll either succeed or fail together.

Posted by Trevor Burrowes on 12 Apr 2010

Good points. Maybe we can feed the world on people power. The Systems should take care and attention from people, but growing food this way is simple and easy, and does not conjure the same visions as do endless digging and plowing. We have to do some further evolution, before we can get to that state of competence.

Jenny Breitner

Posted by Blütenpollen on 14 Apr 2010

The implied argument: A large population can either produce or consume. In most cases, by far, it consumes, and with devastating consequences. So is our large population to be seen as an unused asset, or is it an absolute detriment?

Posted by Trevor Burrowes on 16 Apr 2010

This article, partly, takes a leaf out of the book "Reap" by Colin Tudge. A worthy read.

Posted by Stuart Williams on 24 Apr 2010

As usual, Fred Pearce's writing and thinking about demography make little sense. He must be tickled that we are still adding another 80 million people to the planet each year! Thank goodness Earth is not a finite place and economists are right when they argue that all resources are either infinite or infinitely substitutable. The more of us there are, according to Fred, the happier we'll be. Ah, yes, let us grow at any cost.

Posted by Gary Peters on 24 Apr 2010

In his "Coming Population Crash", Fred Pearce cites Gandhi with approval: "There is enough for everyone´s need, but not for everyone's greed". The falsity of this view was shown by the Italian theorist Gaetano Mosca in 1895: "At a well-served table....everyone can find a way to satisfy,let us say a gargantuan, hunger without pilfering his neighbor's portion. But that is not the case when we are sitting at the allegorical banquet of life. Then the will to get the better of others, to satisfy one´s caprices,passions, lusts, can, unhappily, be boundless and insatiable. A man will try to have ten, a hundred, a thousand portions,so that by distributing them among others he may bend them to his will. In the struggle for preeminence, that man triumphs who can most lavishly dispense the means by which human needs and human vices are satisfied".
Regarding world population, the UN Population Division, the US Bureau of the Census and the Population Reference Bureau agree that the peak population will not be reached until about 2080, and that it will then exceed 10 billion. There is no reason to fear a gradual decline after the peak has been passed.

Posted by Bernard Gilland on 13 May 2010

This is words and good will. As everyone learnt, inferno road is paved with good will and denial. There are two symmetrical problems: a cultural push to overpopulate in traditional human culture (just read the bible and remember all these old man and ladies pressing their youngsters to have kids), because work force is power both for the family and the chief (or the president, ask poutine), and a push to overconsume in today globalized world. Of course, better can be done, but the problem is that better will not be enough if population and human land occupation is not decreasing to make space for a collapsing world ecosystem.

So the problem is not how to twist nature to feed the world, but how to change our approach of life to adapt to the real world that we cannot recreate to our will, especially with the poor understanding we have of it right now.

What i hear and see apart from the peole you are talking about is a completely destroyed nature and land by transportation and industry in europe (no more migratory fishes, no more predator to control pests naturally etc). So knowing that the world could do a better job is nice, but knowing why it is unlikely to do it might be more useful. Because right now the reality is appaling.

You are talking about green revolution, green revolution is oil revolution (pestcicde, fertiliser). Oil will soon be to expensive and phosphate will not finish this century.

Posted by kervennic on 16 Jul 2010



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