What If the World’s Soil Runs Out?

A broken food system is destroying the soil and fuelling health crises as well as conflicts, warns Professor John Crawford of the University of Sydney.

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This is a “what if” interview from the World Economic Forum’s Risk Response Network. To view the rest of the series, click here.

It’s a strange notion, but some experts fear the world, at its current pace of consumption, is running out of useable topsoil. The World Economic Forum, in collaboration with TIME, talked to University of Sydney professor John Crawford on the seismic implications soil erosion and degradation may have in the decades to come.

Is soil really in danger of running out?

A rough calculation of current rates of soil degradation suggests we have about 60 years of topsoil left. Some 40% of soil used for agriculture around the world is classed as either degraded or seriously degraded – the latter means that 70% of the topsoil, the layer allowing plants to grow, is gone. Because of various farming methods that strip the soil of carbon and make it less robust as well as weaker in nutrients, soil is being lost at between 10 and 40 times the rate at which it can be naturally replenished. Even the well-maintained farming land in Europe, which may look idyllic, is being lost at unsustainable rates.
Why haven’t we heard more about this?

Probably because soil isn’t sexy. People don’t always think about how it’s connected with so many other things: health, the environment, security, climate, water. For example, agriculture accounts for 70% of our fresh water use: we pour most of our water straight onto the ground. If soil is not fit for purpose, that water will be wasted, because it washes right through degraded soil and past the root system. Given the enormous potential for conflict over water in the next 20-30 years, you don’t want to exacerbate things by continuing to damage the soil, which is exactly what’s happening now.

(MORE: Feeding the Planet Without Destroying It)

How does soil erosion happen?

Soil is a living material: if you hold a handful of soil, there will be more microorganisms in there than the number of people who have ever lived on the planet. These microbes recycle organic material, which underpins the cycle of life on earth, and also engineer the soil on a tiny level to make it more resilient and better at holding onto water.  Microbes need carbon for food, but carbon is being lost from the soil in a number of ways. Simply put, we take too much from the soil and don’t put enough back. Whereas the classic approach would have been to leave stubble in the field after harvest, this is now often being burnt off, which can make it easier to grow the next crop, or it’s being removed and used for animal feed. Second, carbon is lost by too much disturbance of the soil by over-ploughing and by the misuse of certain fertilizers. And the third problem is overgrazing. If there are too many animals, they eat all the plant growth, and one of the most important ways of getting carbon into the soil is through photosynthesis.

What happens if this isn’t addressed?

There aretwo key issues. One is the loss of soil productivity. Under a business as usual scenario, degraded soil will mean that we will produce 30% less food over the next 20-50 years. This is against a background of projected demand requiring us to grow 50% more food, as the population grows and wealthier people in countries like China and India eat more meat, which takes more land to produce weight-for-weight than, say, rice.

Second, water will reach a crisis point. This issue is already causing conflicts in India, China, Pakistan and the Middle East and before climate change and food security really hit, the next wars are likely to be fought over unsustainable irrigation. Even moderately degraded soil will hold less than half of the water than healthy soil in the same location. If you’re irrigating a crop, you need water to stay in the soil close to the plant roots. However, a staggering paper was published recently indicating that nearly half of the sea level rise since 1960 is due to irrigation water flowing straight past the crops and washing out to sea.

Who will be impacted the most?

Soil erosion is most serious in China, Africa, India and parts of South America. If the food supply goes down, then obviously, the price goes up. The crisis points will hit the poorest countries hardest, in particular those which rely on imports: Egypt, for example, is almost entirely dependent on imports of wheat. The capacity of the planet to produce food is already causing conflict. A lot of people argue that food price hikes caused the Arab spring, and may even have contributed to the recent violence following the release of an anti-Islam film.

(MORE: Food Fight! Stores, Producers, Consumers Battle over High Food Prices)

What about richer countries?

They will have to deal with more refugees fleeing from truly desperate situations. Then there’s the fact that this is happening at a time of economic difficulty in the West, with growing disparities across society and some people already having to resort to charity to feed themselves.  The connection here with health is significant. Cheap food tends to be low in protein and high in carbohydrate, which is exactly the wrong balance for a healthy society. By reducing food to a mere commodity, we have created a system that is degrading the global capacity to continue to produce food, and is fuelling a global epidemic of diabetes and related chronic disease. Obesity in the US cost 150 billion dollars – 20% of the health budget  - in 2008, the latest figures available, and this huge cost will rise as the broken food system takes its toll.

Why is the food system broken?

The big picture is that the amount of land per person has been shrinking over the last 100 years: we now have about a quarter of a hectare per person on the planet and we’re using half of the total land area on the globe for agriculture. If you think of that little quarter hectare, we’re asking more of it than ever before, largely because of population and the modern diet, which is totally inappropriate. Governments have not got this right. We’re subsidising unsustainable food production systems at the cost of our health and our environment. Soil is not costed into food, which means that farmers don’t have the financial capacity to invest in their soil to turn the situation around. Crop breeding is exacerbating this situation. Modern wheat varieties, for example, have half the micronutrients of older strains, and it’s pretty much the same for fruit and vegetables. The focus has been on breeding high-yield crops which can survive on degraded soil, so it’s hardly surprising that 60% of the world’s population is deficient in nutrients like iron. If it’s not in the soil, it’s not in our food.

What should be done about this?

Significant progress is technically quite straightforward. There’s a lot we can do, we just have to choose to do it and provide the right support where it is needed. First-off I’d focus on getting carbon back into the soil, by reversing bad farming practices like tillage, nutrient mismanagement, removing stubble and over-grazing. We can add manure and consider using human waste from cities as fertiliser, instead of just flushing it all out to sea.

In the longer term, breeding targets need to focus more on human nutrition as well as productivity, and on traits that improve the soil. We need to find new ways of bringing together scientists and farmers to harness the expertise of both. From a policy standpoint, probably the most important thing is to find pricing mechanisms that take into account the environmental, health and other costs of a broken system. Farmers need to be appropriately rewarded for regenerating the environment and producing food that supports a healthier society.

Finally we need to recognise that this is a global problem that would benefit from a global approach. We don’t need to reinvent the wheel in each country, and we don’t have time to do so. It takes decades to regenerate soil.  I find it quite ironic that while the Mars Curiosity Rover is poking around looking for life in Martian soil, we’re in the process of extinguishing life in our own.

MORE: Climate Change and Farming: How Not to Go Hungry in a Warmer World


Strangely, it is animals, and not so strangely, biodiversity of micro-organisms and natural weed growth that nurtures our soils. The thought that mono crop production of rice or wheat and vegetables etc replenishes the soil is silly: mono crops are what are destroying our top soils along with the chemicals and pesticides used to force grow less-healthy mono crops.

Returning the land to animals, yes even bovine, is the only way to go. Far more nutrients and human nutrition could be had from this practice.

Paleo understandings in diet and life style is now becoming mainstream and only from this will our soils be replenished.

Paleo is no longer controversial, except in the politically correct. The times are changing and if they don’t, find a plot in the mountains and hope for the best.


We are caught in a vicious cycle of taking unsustainable agricultural shortcuts for their humanitarian cause of 'providing for the growing populace', when we are actually causing the population to grow because of these shortcuts. We then should come up with even worse unsustainable shortcuts to feed even more and more people. -Greg, editor for http://www.primeblog.us


Its great that people want to be organic . . . that works for creating healthier people on a small scale, but does not help the loss of soil.  In order to produce a crop that is organic, you have to till the ground to prevent weeds, then plant the crop, then till the ground to prevent weeds and deal with weeds all season long, because organic means no herbicide, insecticide, or any other chemical. 

If the whole agriculture community went organic, we would be far short of the total production we need to feed the world, we would create more and more soil loss by having to till and not having the residue of prior crops on the ground because of the need to deal with weeds (thereby creating less and less organic matter in the soil), we would also loose many many many more cattle to diseases that are prevented by shots (creating less and less for us all to eat), the dairy milk production would decrease as cattle are moved to grazing systems (for a producer this loss of production is compensated for by not having to spend as much time feeding the cattle, because they find their food on their own). 

Itis great that local people are organic and give the option for people to be healthier by buying their produce . . . but organic is far less environmentally friendly than you would believe.  For everyone to be organic is an awesome goal, but in the scale of the world it is unrealistic. 


This article is a must read for every human on earth!

It is in our hands to solve the problem, but we will need the political will.

1.Stop erosion and soil degradation as well as desertification which we cannot afford in view of the need to feed a rising world population.

2.Stop soil mining (extraction without reposition) and depletion of organic matter in the soils and instead use sustainable agricultural production systems

3.Expand conservation agriculture based on No-tillage (Zero tillage) to those regions and soils in the world where these practices are still not used (about 90% of the area). This will need resources for research and development as well as for extension and diffusion.


This is a decent article right up until the point where they talk about what can be done.  After reading what can be done, the consumer will have no idea what he or she can do as an individual to help alleviate the problem.  Then they go on to talk about that it's a global issue.  Well, this really makes an individual feel powerless.  The fact of the matter is you can do something and the transition to sustainability will start locally.  

Local organic produce is food that is produced in a sustainable way, most likely grown with compost, not hormone/antibiotic-injected animal feces.  Eat it.  

For example, a local organic tomato will have many more vitamins and minerals and is not sprayed with chemicals to make it ripen.  Additionally, it is not shipped across the country to a supermarket.  Yes it may be more expensive to buy, but the cost of the soil, water, animal waste, fuel, environment, and human health that comes with mass produced food items certainly costs more.


This article does bring awareness of a critical issue to the masses.  However, they solutions suggested are archaic and incomplete.  The use of human sewage on soil would only intensify the issue, as it contains so many toxic pharmaceuticals and other toxic chemicals we ingest.  In fact, even manure should be from animals feed organic high quality feed appropriate to their species (that means cows eat grass) and composted aerobically first.  It also means we must stop using chemicals on our crops and our soils.  Hemp is a crop that when grown in rotation with other crops actually increases the health of the soil.  This article seems to indicate that livestock is bad as well since it is associated with over grazing.  That is poor land management.  There are livestock land management practices that actually increase the health of the soil.  Allan Savory and Joel Salatin are good sources of this information.


I agree with, " probably the most important thing is to find pricing mechanisms that take into account the environmental, health and other costs of a broken system".  A demonstrated model of this system is called EcoCommerce, which allows a new economic concept to emerge called "symbiotic demand" .  This was described in EcoCommerce 101 and is illustrated at https://prezi.com/87xwfvhpnas0/symbiotic-demand/ 


We can't use human waste, since most of it nowadays is full of pharmaceutical compounds, thanks to the pill popping culture.


Overall, humans aren't that bright. In fact, on the whole we're pretty stupid and greedy. This is just more proof. Now all the nut jobs are stocking up on AR15's and assault rifles INSTEAD OF LISTENING TO THE SCIENTIFIC COMMUNITY. This is not going to end well.


it is Biblical;  

The Terra Preta Prayer
Our Carbon who art in heaven, Hallowed be thy name

By kingdom come, thy will be done, IN the Earth to make it Heaven.

It will give us each day our daily bread and forgive us our atmospheric trespasses

As we forgive those who trespass against the Kyoto protocols

And lead us not into fossil fuel temptation, but deliver us from it's evil

low as we walk through the valley of the shadow of Global Warming,

I will feel no evil, your Bio-fuels and fertile microbes will comfort me,

For thine is the fungal kingdom,

and the microbe power,

and the Sequestration Glory,

For ever and ever (well at least 2000 years)


Soil Carbon Dream
I have a dream that one day we live in a nation where progress will
not be judged by the production yields of our fields, but by the color
of their soils and by the Carbon content of their character.
I have a dream today.
I have a dream that one day, a suite of earth sensing satellites
will level the playing field, giving every farmer a full account of
carbon he sequesters. That Soil Carbon is given as the final arbiter,
the common currency, accountant and Judge of Stuartship on our lands.
I have a dream today.
I have a dream that one day every valley shall be exalted, every
hill and mountain shall be made forest, the rough soils will be made
fertile, and the crooked Carbon Marketeers will be made straight, and
the glory of Soil Sequestration shall be revealed, and all flesh shall
see a Mutually assured Sustainability.
This is our hope.

My apologies to Dr. King, but I think he would understand my passion



Reality check for the modern consumer age. Lawns will be turned into food gardens, composting and even "night soil" will become survival tools as the U.S. Dollar is watered down by the feds to Zimbabwe Bucks. Walking folks will replace the cars, few will be able to find jobs after the Chinese "population Bomb" is set off, and Thorium will be the power of the Pan Eurasian empire, leaving the western world stuck on stupid, radio active waste ridden, and scarce oil dependent. Western World Mongrel Trash already unwelcome in the new reality. We must guard our soil for our very lives in a world changing at computer pace now, and examine closely the real corporate morality and aims and goals. Straw Bale, Hemp Bale and Hempcrete blocks, and de urbanization to sustainable lifestyles may be an answer for a large part of humanity - a humanity that cannot survive without good healthy well husbanded top soils - it is Biblical.


Fertile soil doesn't fall from the sky. The contribution of bacterial remnants to soil fertility has been underestimated until now
14 December 2012
Helmholtz Centre For Environmental Research - UFZ

The contribution of bacterial remnants to soil fertility has been underestimated until now
Remains of dead bacteria have far greater meaning for soils than previously assumed. Around 40 per cent of the microbial biomass is converted to organic soil components,  {} Until now It was assumed that the organic components of the soil were comprised mostly of decomposed plant material which is directly converted to humic substances. In a laboratory experiment and in field testing the researchers have now refuted this thesis. Evidently the easily biologically degradable plant material is initially converted to microbial biomass which then provides the source material to soil organic matter.

However, when I read of the discovery at the Advanced Light Source, with new NMR techniques, about fungal potassium being the primary nucleating catalyst for rain. That vision of how life calls the rain is another unaccounted for ecological serviceprovided the fungal kingdom in a healthy soil.

How Fungi May Create the Amazon's Clouds ; http://discovermagazine.com/2012/sep/04-mushroom-cloud


Demonstration, Using quantitative 13C nuclear magnetic resonance (NMR) spectroscopy measurements, concludes that both Terra Preta soils and Midwest dark soils contain 40%+ of their organic carbon (SOC) as pyrolytic carbon, that this pyrolytic carbon can account for all CEC

Abundant and Stable Char Residues in Soils: Implications for Soil Fertility and Carbon
Sequestration , J.-D. Mao, R. L. Johnson, J. Lehmann, D. C. Olk, E. G. Neves,
M. L. Thompson and K. Schmidt-Rohr, Environ. Sci. Technol.,  http://pubs.acs.org/doi/abs/10.1021/es301107c

New avenues of confirmation, new pathways for applications are cropping up all over. The vision of the fungal world calling
the rain, The farms in Switzerland eliminating odor of manure,closing the nutrient loop with Biochar feed rations provide a feast of new learning and imagination.


Agreed, annual grain agriculture, the way it is practiced now, is monstrously horrific.  Perennial systems, such as tree cropping savanna systems and pasture/rangeland systems are reversing soil loss and desertification where well managed and not overgrazed, and feeding more mammals in nature than other systems.  Look up Colin Seis' pasture cropping methods in Australia and see how grains can be grown more profitably with little erosion, while adding soil carbon and building topsoil.  Mark Shepard's new book, Restoration Agriculture, is a remarkable discourse on mimicking nature to create abundant and profitable agricultural systems.  We need to quickly learn the regenerative methods that will reverse the downward spiral we are in.

"First-off I’d focus on getting carbon back into the soil, by reversing bad farming practices like tillage, nutrient mismanagement, removing stubble and over-grazing."  Very important.  An excellent first step.  "We can add manure and consider using human waste from cities as fertiliser, instead of just flushing it all out to sea."  Also true, but these amount to what John Kempf calls importing carbon and carbon generation.  

Nature has a way of doing much more than that.  Kempf calls it carbon induction.  http://www.nofamass.org/sites/default/files/attachments/Carbon_Building_Carbon_Cycling_John_Kempf.pdf.   According to Horst Marschner, Mineral Nutrition and Higher Plants, a healthy plant can exude sugars, lipids, and amino acids into the root zone at 60-70% of net productivity of the plant.

Photosynthesis uses CO2 from the atmosphere and, combined with water, form sugars which are manufactured into the other substances by plant dna.  The exudates are used to feed soil microbes which eventually become humic substances -- stable carbon sinks which help soils aggregate and hold moisture. So a plant weighing 100 gm above ground may have a root system of 100 gm, for a total plant mass of 200 gm. If 2/3 of the plant productivity is microbe food, then that is another 400 gm, or 600 grams of total productivity from a plant which is only 100 gm of green matter.  Every ton of pasture can produce five tons in the soil, much of that becoming new topsoil.  While other methods take more work and produce less topsoil, induction lets nature do most of the heavy lifting.  Managed grazing, http://www.savoryinstitute.com/,  loosening subsoil using for instance a Yeomans keyline plow, and addition of soil biology can assist nature in this mighty task.

The whole key is that we need much more life on the planet and IN the planet to get it again functioning as a healthy system.  Without it, 50 million acres per year of desertification, 150 species extinct daily, 35 million acres per year of deforestation, in addition to the erosion and flooding, will continue to take its toll.  We will lose our home, with nowhere else to go.  It is up to those of us who envision the possibilities that more life can bring, to make the choices, find the vacant land, help the farmer, learn about grazing, and figure out how to help make this happen.  Doom and gloom, and passing the buck are not part of this formula.  Find some acres and get started!

See also www.soilcarboncoalition.org, and www.amazingcarbon.com.

One more note.  "... soil isn’t sexy."  Sorry, but according to Australian carbon farmer Darren Doherty, "Soils are Seq-C."  It's true!



Endowment and Security for the future can be obtained by implementingthe Accounting of soil carbon as the base measurement of sustainability for all  Ag and Biofuel ventures. 

Aligning incentives to get a farmer paid for their good works is where carbon markets should all grow from. The farmer will always have the lowest cost system for sequestration of carbon and it is about time that the carbon markets recognize that as it's very foundation. A foundation far more secure than any other market, certainly Wall Street or even US savings bonds. All political persuasions agree, Building soil carbon is good. 

The timing for this is also very good with California instituting a carbon cap and trade system, with Australia moving forward with their carbon farming initiative and Canada, at least Alberta, considering carbon farming.Re-Building the World's Soil: The Role of Soil Carbon Methodology for U.S. and Global Carbon Offset Projectshttp://www.prweb.com/releases/2012/12/prweb10185341.htm

 For anyone interested in, or confused by, Biochar Soil Technologies, Please view my presentation and slides of this openingtalk for the USBI Biochar conference in Sonoma California. This is the third US Biochar conference,after ISU 2010 and Colorado 2009 

Carbon Conservation for Home, Health, Energy & Climate 


Modern Thermal conversion of biomass burns only the hydrocarbons in that biomass, conserving the carbon for the soil. At the large farm orvillage scale modern pyrolysis reactors can relieve energy poverty, food insecurity and decreased dependency on chemical fertilizers.Pleasetake a look at this YouTube video by the CEO of CoolPlanet Biofuels, guided by Google's Ethos and funding, along with GE, BP and Conoco, they are now building the reactors that convert 1 ton of biomass to 75 gallons of bio – gasoline and 1/3 ton Biochar for soil carbonsequestration.



human extinct in about 100 years .... other species will regroup and grow after that ... a new smarter evolution will hopefully happen ...


Common sense says that over time the world population can only equal what each acre of land can sustainably produce times the number of arable acres.  We are caught in a vicious cycle of taking unsustainable agricultural shortcuts for the humanitarian cause of 'providing for the growing population', when we are actually causing the population to grow because of these shortcuts.  We then need to come up with even worse unsustainable shortcuts to feed even more people.  As we of course will do nothing about this situation, nature will sadly adjust in her own horrific way. 


No comments, huh... imagine that.  Humankind is working very hard towards its own end.  C'est la vie.


@BPts How does tilling results in soil loss ? Tilling creates oxygenated environment for the soil, which is actually more healthy for soil. Only thing you have to prevent is runoff because of rains, which is easy. Btw we have no need of dairy and cattle's, they are incredible but meaningless burden on all of us and environment,


What about the organic garlic from most stores in America . . . it is grown in China, and shipped over to to America. 

Is it better to look at food as better for myself when I eat/use it, or look at food as better for the global system when I eat/use it?   Check it out in your local stores . . . you will be surprised at where organic garlic comes from.


Ultimately it will be up to consumers to make the change.  This should not be a political issue where we rely on our government to do something.  Vote at the grocery store with your wallets.


@jdyer2  It is a nightmare that we can avoid but governments, big corporations and their interests will be tough contenders with which to work. Crazy new ideas like Paleo and free energy and a return to the understanding and teaching of true science, (the four principles of the scientific method, honestly followed)  may be on the horizon to a new norm as our only hope. We must learn to think and question outside the box that has caused our problems. Peer review as it is now practiced must be investigated and returned to its relevant intention and purpose. I believe in the power of our species to find the answers. Sometimes the clearest thinking can come when one’s back is to the wall.


This article is very helpful:)