By David L. Brown
How thin is the line that divides world food supplies from famine? This thin: If China were to import another five percent of its total grain needs, it would completely eliminate all grain available in the world’s export markets.
The reason why this is is possible is due to the rapid industrialization of China. Prime farmland is being replaced by roads, factories, houses, and parking lots. Production of wheat, rice and corn is moving to lower quality land, and areas more prone to drought and heat events. Add in the growing number of Chinese, and their desire to consume more calories, and you have an interesting collision of forces.
Of course, I have written here before that I believe China is heading for a fall. The rising new middle class there may soon be a receding one, and industrialization already is slowing due to the collapse of export markets and may soon recede as well. But nevermind, the point of the statement above is to illustrate how vulnerable the Earth has become to food shortages.
The factoid I quoted (from this article on the Seed Daily web site) is merely one example of the forces at work as rising human population meets the declining resources of the planet. There are similar examples everywhere you look. Fisheries have virtually collapsed and trawlers are busy dredging the last living things from our oceans. Tillable land is being converted to uses other than agriculture, while soil erosion chips away at what is left. Resources of fresh water are being pumped from aquifers deep in the Earth, water that is not being replaced. These water sources will eventually run dry, and in fact already have done so in some places (i.e., Saudi Arabia).
The present economic slowdown may be the best news for the world, because it will slow the rising demand for higher standards of living, cause funding for infrastructure projects that gobble up farmland, and generally put a brake on the runaway train that the world economy has become. It may even help slow and reverse the growth of human numbers, which is the root cause of the threats to our ecosystem and the very future of civilization.
Yes, that may seem cold-hearted but it is appropriate on this 200th anniversary year of the birth of Charles Darwin to remember that the future belongs to the fittest, and that Mother Nature wields a pruning knife. Species come and go, adapt and evolve, and natural selection applies to all species including homo sapiens.
I suspect that Nature has never had to deal with anything quite like us, so it is not easy to predict how things will turn out. One lesson I think we can draw from geologic history is that conditions can turn on a dime. We all know the story of the asteroid that ended the Age of Dinosaurs. But more recently we have learned that the Younger Dryas, a thousand year return to Ice Age conditions about 12,000 years ago may have been caused by a comet impact over North America that could have killed off the Clovis human population as well as many of the megafauna that previously inhabited the hemisphere. Similar if less devastating events have happened at regular intervals throughout history. Such comet or asteroid strikes can affect the climate worldwide, creating short term freak cold spells or even, as in the case of the Younger Dryas, a centuries-long return to glacial periods.
Another worldwide effect results from major volcanic eruptions. Just a couple of decades ago we experienced the Mount Pinatubo eruption that cooled the entire Earth for several years. We are presently experiencing cooler conditions due to an unusual number of smaller eruptions during 2008.
Point: Human population and agricultural production is already balanced on the edge of disaster. What happens if even a modest climate-changing event should take place, such as Pinatubo? A reduction of just a few percentage points in world crop yields would be a disaster. A significant drop of 20 or 30 percent would mean absolute calamity. And, any study of history will tell us that such events are relatively common. In the brief period of time since about the end of WWII conditions have remained generally favorable. In the future, historians may consider that a tragedy rather than a boon, because it has allowed humanity to grow far beyond the ability of the Earth to sustain us.