December 15, 2006

The impact of modern agriculture on land use

Agriculture has only been around for about 10,000 years and the reasons for its success are not clear since the archeological evidence suggests that early farmers were, nutritionally speaking, not as well off as their contemporary hunter-gatherers. It may have been that since grains can be stored over years of bounty and used in lean years, farmers were better able to withstand adverse times and thus better able to sustain themselves over longer times than their rivals in lifestyles.

However, the rise of agriculture led to some serious distortions in the use of land. In nature, diversity abounds, for the simple reason that different plants species provide services for others. Some provide shade, others fix nitrogen, others protect from wind, others retain water, and so on, each enabling the others to flourish. So natural lands tend to produce a mixture of these various forms of life. The widespread growth of farming and the use of lands for single crops like rice, wheat, and corn marked a significant change since it stripped the land of its diversity.

These crops like wheat, rice, and corn have some advantages. Mainly they transform solar energy into bundles of carbohydrate energy that are tight, transportable, and relatively long lasting. Apart from the hydrocarbons like oil, these are the most concentrated form of energy. But in creating this new form of agricultural energy, we have been essentially drawing upon the reserves of energy created and stored in the land over periods of millions of years before the arrival of agriculture.

Most of this stored agricultural energy existed in the form of prairies. In his February 2004 Harper's essay The oil we eat, Richard Manning describes how energy from the Sun is stored in this particular form of plants.

A prairie converts that energy to flowers and roots and stems, which in turn pass back into the ground as dead organic matter. The layers of topsoil build up into a rich repository of energy, a bank. A farm field appropriates that energy, puts it into seeds we can eat.

The cost of using that topsoil for farming is apparent, according to Manning. "Walk from the prairie to the field, and you probably will step down about six feet, as if the land had been stolen from beneath you." This represent our using up of the world's long accumulated energy capital that has been stored in the soil. Jared Diamond in his book Collapse: How Societies Choose to Fail or Succeed (p. 489) similarly saw a visual example of this during a recent visit to Iowa where a church had been built in the 19th century in the middle of farmland. As a result of the land around it being cultivated over the years and using up the stored resources in the soil, the church now stands like an island about ten feet above its surroundings.

As we use up this soil this way, we have to replenish it using artificial fertilizers. "Oil is annual primary productivity stored as hydrocarbons, a trust fund of sorts, built up over many thousands of years. On average, it takes 5.5 gallons of fossil energy to restore a year's worth of lost fertility to an acre of eroded land—in 1997 we burned through more than 400 years' worth of ancient fossilized productivity, most of it from someplace else."

So after using up our inheritance that was in the rich soils, we use up our inheritance that was stored in the form of oil to cover up for the first loss, borrowing from Peter to pay Paul, so to speak. This process was accelerated by the arrival of what are called "wheat-beef" farming people six thousand years ago who, within the relatively short time of 300 years, became the dominant agricultural group, pretty much eliminating the hunter-gatherers. But single crop agriculture like wheat depletes the soils, leading to famines. Manning points out that between the years of 500 and 1500, "Britain suffered a major "corrective" famine about every ten years; there were seventy-five in France during the same period."

However, as these two countries became sea-faring colonial powers, they were able to use the riches of the colonies to reduce the famines at home. This also led to inequalities in resource consumption between the colonizers and the colonized.

But as the populations of these wheat-beef communities grew because of the abundance of food, they had to keep moving on, finding new sources of prairie grasslands to conquer and use up. After they arrived in the US, this drive to open up fresh lands happened here too, as settlers moved west searching for new land in order to tap its vast reserves of soil energy.

But at some point the sources of new land became exhausted. There were no new prairie frontiers to exploit. So then what happened? The 'green revolution' occurred in which genetic modifications produced rice, when and corn species that, combined with the use of increased irrigation and artificial fertilizers, produced three times the yield they had before. Most people might think that this was a good thing, since it enables the production of more food that can feed more people more cheaply. Manning argues that this is the worst thing to have happened.

One reason, Manning argues, is that it moved poor people off their own land while enabling their growth in numbers. "In the forty-year period beginning about 1960, the world's population doubled, adding virtually the entire increase of 3 billion to the world's poorest classes, the most fecund classes. The way in which the green revolution raised that grain contributed hugely to the population boom, and it is the weight of the population that leaves humanity in its present untenable position. . .[T]he methods of the green revolution . . . added orders of magnitude to the devastation. By mining the iron for tractors, drilling the new oil to fuel them and to make nitrogen fertilizers, and by taking the water that rain and rivers had meant for other lands, farming had extended its boundaries, its dominion, to lands that were not farmable."

It is clear that we cannot go on consuming resources at this rate. It seems to me like we have only three choices:

1. Perpetuate existing wide disparities in rates of consumption by the use of brute force. This will inevitably lead to more and more global conflicts, and an inevitable collapse as resources get used up.
2. Allow for increased rates of consumption globally as the newly emerging countries like China and India also start to consume at current first world rates. This will lead to an even more rapid global collapse than option 1 since resources will be used up even more quickly.
3. Reduce consumption rates in the first world while at the same time making resources more equitable worldwide so that we can bring worldwide rates to a level that is sustainable and yet provides the world's population with a decent although not luxurious standard of living.

While I favor the third option, that requires global cooperation and sharing, ideas that are not that popular these days. I fear that the other two options are more likely to be adopted.

POST SCRIPT: Middle East politics round up

The invaluable Juan Cole gives a handy round up on the state of play in the Middle East, including the emergence of Saudi Arabian interests as a big factor. He also discusses something that has not been emphasized much in the media, and that is the possible reason why Dick Cheney was "summoned" to Saudi Arabia just after Thanksgiving and was "read the riot act" by the Saudi king, and the abrupt resignation this week of the Saudi ambassador to the US.

The fact that the Saudis can snap their fingers and Cheney immediately gets on a plane and goes to get lectured by them is another indication of how weakened the US has become by its invasion of Iraq. At least we can be thankful that Cheney didn't shoot the Saudi king in the face.


Trackback URL for this entry is:


I have read this article and found it to be very useful. I have come to notice that this article is written very professionally and would like to share it with my friends. Thanks for providing us such a nice informative Article!

Posted by Add Link or Submit Link to Agriculture Directory on September 1, 2008 11:53 PM

very good informative article...its real this modern technology impacts on agriculture on land use

Posted by Online Doctor Consultation on September 19, 2008 01:02 AM

agricultures are backbone to the world to lead healthy life

Posted by Online Doctor Appointment on November 11, 2008 12:48 AM

I have graduated in Applied physics. I really like the article and the information you share, especially "the reserves of energy created and stored in the land over periods". People start thinking on it and need to have proper research on this area. Thanks for this article.

Posted by Drip Irrigation on January 30, 2009 03:40 AM

I think it's about time we had a radical rethink of our agricultural policies and started working with nature instead of treating her like a servant we can flog to death.

Posted by Solar Can Save Us on July 24, 2010 11:46 AM

Sadly, I agree with your conclusion. The idea of first world countries agreeing to take sensible action is noble and logical, but it has rarely occurred historically and the current economic pressures pretty much make it a non-starter. I am also interested in your thoughts on the reduction in the types of seeds available per species. I've read that the seeds for soybeans have been reduced to three or four different strains. Would this not lead to a bigger risk of famine due to disease?

Posted by Solar Energy on July 26, 2010 02:43 PM

Well, I really really liked the article. But this what will happen..The same way when we went to war in the desert. You have to build up.

And that is exactly what will happen. All those movies about flying this and that,, well you first begin to see farms being built up..

And then the other technologies will come into existences. But that is what will be happening. People are starting to think outside that box...Also you heard that first from Jordan Eske...Farm land will start building up and then buyers will be leasing levels and so on..

Posted by solarbatterycharger on July 29, 2010 02:22 PM

"...As we use up this soil this way, we have to replenish it using artificial fertilizers..." A not so good alternative to getting the ideal way of fertilizing soil. Why not resort to using organics? It is so far the best way to replenish the use up soil.

Posted by caring for roses on July 30, 2010 04:26 AM

I am also interested in these seeds? Please write an article about that. I would love to know more.
Also, I like that idea about the farming up...I think though that in order for that to happen, they have to figure out how that piping and sunshine would get into the land. I am sure it would be some complex thing, but it is possible. If I find an article I will post it here for others.
Lastly, that really stinks about more global conflicts. When can we think ourselves into a way of peace instead of conflict, with our minds so smart and complex, you would think we would have that figured out..

Posted by linkmagnet on July 30, 2010 10:50 PM

The third choice promotes good camaraderie at its highest level. But implementing it effectively proves to be an "impossible dream"?

Posted by fathers day gifts on July 31, 2010 08:57 PM

I have been publicly speaking on the subject of conservation for years. Now that it is as apparent as it is what is coming I still do not see a shift of the masses to support life remaining on earth. I wish more people would realize the information in your post is something they can use to direct or mitigate what is coming.

Posted by Fertility Spell on August 4, 2010 02:15 AM

I think option one will run us into the ground faster than option two. Conflict burns more resources such as oil much faster then peace.

Posted by Computer Repair on August 4, 2010 02:19 AM

I am a little concerned about your claim that it would be helpful to reduce the types of seeds available currently in each species. It seems like it might lead to more rapid decline and eventual extinction.

Posted by Ida Topps on November 24, 2010 02:58 PM

I think no 3 is the solution: Reduce consumption rates in the first world while at the same time making resources more equitable worldwide.

Posted by Dan on March 2, 2011 04:24 AM

We inherited rich soils from Mother Nature, but our inheritance has been ravaged by chemicals.

The rich soil is still possible with the microbial and mineral balance restored. Without this balance you have dead soil.

Posted by Tim on May 13, 2011 09:27 PM


Might it not be argued the Arab Spring is being sparked by rising food prices that have effectively acted as the "last straw" in Egypt, Tunisia and so on. I believe it is so and many people view this as an isolated event in the Mideast, but I think it could spread to other countries who face similar problems.

Perhaps I am just becoming a bit paranoid, but it seems we are on the cusp of huge resource problems in many areas. We face problems with water, oil, rare minerals, copper and who knows what else. These would seem to paint a picture of overuse, but I can't see how it will subside given our every growing population as a species. While I too would like to see an adult discussion in the world about moderation, I fear war and conflict will be the practical result of these problems. It seems to be so at the moment. Thoughts?


Posted by Richard on June 18, 2011 04:38 PM

I too have the sense that we are on the brink of a resource problem that we are not paying attention to. I elaborated on this theme in this post.

Posted by Mano on June 20, 2011 06:07 PM

The agricultural revolution is the backbone of the industrial and technological revolutions, freeing up man-hours. We could easily ruin our soil and be forced to hydropnics (much more expnesive) if we are not careful. Solar control such as with solar window films could aid us with our resource problems that Richard above mentioned.

Posted by Joe Davidson on September 13, 2011 01:48 PM

It was topical for me to see this interpretation of solar energy with respect to grains:

**These crops like wheat, rice, and corn have some advantages. Mainly they transform solar energy into bundles of carbohydrate energy that are tight, transportable, and relatively long lasting. Apart from the hydrocarbons like oil, these are the most concentrated form of energy. But in creating this new form of agricultural energy, we have been essentially drawing upon the reserves of energy created and stored in the land over periods of millions of years before the arrival of agriculture.**

I had just been explaining to cousins on the weekend about where the energy comes from.

I agree with the article, I think it is more likely choices one and two will be selected in the absence of a global fairness movement. Working in the solar industry in Sydney, I've noticed a massive swing in attitudes away from doing solar because it is right and will help others+future generations, to a climate of 'I need to see 30% return from this before I'll consider it'.

Posted by Thomas Bywater on November 1, 2011 09:37 PM

So many people are talking about the economy and how we are leaving behind a massive debt for our children.

Your article reveals a much more serious - and global - debt that is being created every time we eat a bowl of Kellogs - or fuel up with corn-based ethanol.

I hope this becomes a message that reverberates outside of the scientific community and into public consciousness.

Posted by Quinton Hamp on November 5, 2011 09:36 PM