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  • From: "Tradingpost" <tradingpost@lobo.net>
  • To: livingontheland@lists.ibiblio.org
  • Subject: [Livingontheland] Food and Population
  • Date: Wed, 03 Feb 2010 16:14:54 -0700



Food and Population
by Peter Goodchild 01 February 2010
http://www.culturechange.org/cms/index.php?option=com_content&task=view&id=600&Itemid=1

Farmers are invisible people, and middle-class city dwellers choose to
pretend that the long lines of trucks bringing food into the city at dawn
every day have nothing to do with the white-collar world. Perhaps it is a
mark of the civilized person to believe that the essentials of food,
clothing, and shelter have no relevance to daily life. Yet if the farmers
stopped sending food into the great vacuum of the metropolis, the great maw
of urbanity, the city would soon start to crumble, as Britain discovered in
the year 2000 [5]. The next question, then, is: Where does all this food come
from?

Is there such a thing as sustainable agriculture, or is “sustainable
agriculture” a self-contradictory term? To keep a piece of land producing
crops, it is necessary to maintain a high level of various minerals. The most
critical are phosphorus (P), potassium (K), and especially nitrogen (N).
These minerals might be abundant in the soil before any cultivation is done,
but whenever crops are harvested a certain amount of the three critical
elements is removed.

The native people of North America had a simple solution: abandonment [3]. No
fertilizer was used, except for the ashes from burned undergrowth and corn
stalks. As a result, the soil became exhausted after a few years, so the
fields were abandoned and new ones were dug. Primitive agriculture in many
other parts of the world has been similar, and sometimes such a technique is
called “slash-and-burn.”

A common partial solution to the N-P-K problem, used in many countries for
centuries, has been to turn crop waste into compost and put it back onto the
land. The problem with that technique, however, is that one cannot create a
perpetual-motion machine: every time the compost is recycled, a certain
amount of N-P-K is lost, mainly in the form of human and animal excrement
(after the crops are eaten) but also as direct leaching and evaporation. One
can come closer to sustainability by recycling those human and animal wastes,
but the recycling will always be less than perfect. After all, nitrogen,
phosphorus, and potassium are elements, and by definition they cannot be
created. Of the three elements, nitrogen is by far the most subject to loss
by leaching, but to some extent that can also happen with phosphorus and
potassium.

In the original organic-gardening movement pioneered by Sir Albert Howard in
the early years of the twentieth century, nothing but vegetable compost and
animal manure was allowed. In modern organic gardening, a common technique is
to replace lost minerals by adding rock powders, particularly rock phosphate
and granite dust. For most present-day gardeners and farmers, the usual
response to the problem of soil replenishment is to apply artificial
fertilizer, N-P-K largely derived from those same types of rock used in
organic gardening. (In fact, the use of rock powders in later organic
gardening sounds suspiciously like a drift toward artificial fertilizers.)
When the fragile international networks of civilization break down, however,
then neither rock powders nor artificial fertilizer will be readily
available. These materials are very much the products of civilization,
requiring a market system that ties together an entire country, or an entire
world.

Writing early in the twentieth century [4], F.H. King claimed that farmers in
China, Japan, and Korea were managing to grow abundant crops on about one
tenth as much cultivable land per capita as Americans, and that they had done
so for four thousand years. If they kept their land producing for 40
centuries, what was their secret? The answer, in part, is that most of
eastern Asia has an excellent climate, with rainfall most abundant when it is
most needed. More importantly, agriculture was sustained by the practice of
returning almost all waste to the soil — even human excrement from the cities
was carried long distances to the farms. Various legumes, grown in the fields
between the planting of food crops, fixed atmospheric nitrogen in the soil.
Much of the annually depleted N-P-K, however, was replaced by taking
vegetation from the hillsides and mountains, and by the use of silt, which
was taken from the irrigation canals but which originated in the mountains.
The system, therefore, was not a closed system, because it took materials
from outside the farms.

These three countries are, in any case, problematic as sources of
agricultural “wisdom.” King remarks that “the first days of travel in these
old countries force the over-crowding upon the attention as nothing else
can.” In a chapter on Tientsin, he cites a Scottish physician’s description
of a common solution to over-crowding: “In times of famine the girls
especially are disposed of, often permitted to die when very young for lack
of care. Many are sold at such times to go into other provinces.” As for the
hard labor and low remuneration, King says of a Japanese rice farmer that “it
is difficult for Americans to understand how it is possible for the will of
man, even when spurred by the love of home and family, to hold flesh to tasks
like these.” The “miracle” of growing so much food on so little land was
largely due, therefore, to neither technology nor topography, but to the fact
that starvation was the only alternative.

Besides using vegetable compost and animal manure for increasing the
sustainability of agricultural land, many societies have employed related
techniques, such as crop-rotation, fallowing, cover-cropping, and green
manuring. If any of these techniques includes the use of legumes, nitrogen is
added to the soil. Such practices also replenish the humus content of the
soil, important for retaining moisture and minerals.

In some societies, agriculture meant slow but inexorable burnout, as was the
case for most of Europe. In other cultures (China, Japan, Korea etc.) the
response was to recycle intensively. As much as possible, vegetable compost
and human and animal excrement had to be reclaimed, and other loss was made
up by importing soil and vegetation from the wilderness. Even for those
cultures, however, a growing population exacerbated the problems.

Vernon Gill Carter and Tom Dale [2] claim that all previous civilizations
have managed to destroy their agricultural systems, except for a few
societies that were lucky enough to have sufficient annual flooding, thereby
replenishing their soils from an outside source. The Egyptians long ago had
such replenishment from the Nile, which brought a small but sufficient annual
supply of silt from the highlands of Ethiopia and central Africa; it was
Egyptian grain that kept the Roman Empire alive. The inhabitants of
Mesopotamia received new silt annually from the Tigris and Euphrates. Carter
and Dale regard the Indus Valley civilization as in a similar situation to
that of Mesopotamia. Perhaps the situation of China, Korea, and especially
Japan is similar to that of Egypt, since all three Asian countries (as
described by King) used to derive much of their soil fertility from
river-borne silt. In describing the Far East, however, Carter and Dale are
generally closer to the mark than King. Speaking of China, they note that
“erosion as a whole continues to ruin much of the land, reducing China, as a
whole, to the status of a poor country with poor undernourished people,
mainly because the land has been misused for so long.”

In the first chapter of Walden, Thoreau says that it would be better “to
select a fresh spot from time to time than to manure the old.” Perhaps he was
right. His method, which is essentially the type of practice referred to
above as abandonment, might not be ecologically sound, since on a large scale
it would mean leaving behind a long string of what used to be called
“worked-out farms.” For a large population of farmers and consumers, such a
method would be impractical, although many ancient cultures tried it. On a
very small scale, however, it might not be so ecologically unsound, since the
abandoned spot would, over many years, revert to reasonably fertile land,
particularly if there were wild legumes to replace the nitrogen.

One further possible disadvantage to Thoreau’s suggestion is that preparing
the “fresh spot” might require a good deal of work. It is noteworthy that the
native North Americans preferred forest, rather than grassland, as sites for
agriculture — the forest land was more fertile, and digging up heavy sod
(especially on the prairies) would have been arduous with the available
tools. The native people girdled the trees (cutting a ring of bark from
around each tree) to kill them, and then felled the trees much later, with
fire and axes.

Actually, if the abandoned land is taken up again at a later date, the
practice of abandonment tends to fade into that of fallowing, another
practice to be found in many societies. With the traditional European method
of fallowing, half the land is left to revert to grass and weeds for a year
before being plowed again. Alternately, a farmer’s land might be divided into
three parts, and the fallow portion might be part of a system of crop
rotation.

World agriculture faces the problem of a reduction in arable land, but there
is also the problem of water. The natural availability of water has always
been one of the most critical factors in farming. Nearly half of the United
States receives only 20 inches or less rainfall annually. Low precipitation,
however, is a problem on every continent. In a real survival situation, what
are the chances that anyone would be able to pick up a plastic hose and get
an endless supply of clear cold water? Not very great. Even wells, cisterns,
and ponds would be useless if their water flow had been controlled by
electricity. When water must be pumped by hand or carried in buckets, it
becomes a precious commodity.

One possible response to aridity is dry farming, leaving crops at the mercy
of the weather, relying solely on whatever rain may fall [4]. Grains,
legumes, potatoes, and several other crops can be farmed in this way. “Dry
farming” will again become a popular term, as the aquifers run out of water
and modern systems of agriculture become largely impossible. The essence of
dry farming is to space out plants so that the distance between them is two
or three times greater than usual. The roots can thereby spread out in all
directions, finding water that has been stored in the ground in previous
months. Because each plant has more room in which to grow, reducing plant
density does not lower the total yield by an equal amount. To make the best
use of the water in the ground, all weeds must be removed, because most water
vanishes by evaporating from the leaves of any plants that are growing on
that soil. The ground must be hoed or otherwise cultivated frequently, so
that the surface is kept watertight under a “dust mulch”: water does not
easily pass through a layer of well-disturbed dust, since the lack of water
and the separation of soil particles prevent capillary action [6]. Further
conservation of soil moisture can be achieved by the use of windbreaks. Dry
farming is an excellent means of producing food without dependence on complex
technology. Dry farming, however, can only make better use of the world’s
soil; it cannot increase the yield of the world’s crops.

But the world’s food problems cannot be solved merely by devising a method to
increase agriculture. The world’s human population is now approaching 7
billion, while the amount of arable land is not great. Massive inputs of
artificial fertilizers and pesticides only replace one problem with others:
poisoned water, eroded soil, and insufficient humus. Even the world’s present
arable land is rapidly disappearing under cities and highways. Nor can we
extend that land by pumping more water from underground, because the aquifers
cannot be made to yield more water than they receive.

The real solutions bear little resemblance to anything that is intellectually
fashionable. What is of primary importance is to discard the glib, facile
sermons that are often tacked on: “We must do such-and-such” or “We have to
do such-and-such.” After all, who is the “we” in these statements? If “we”
means the poor and powerless, then the statements may be false, because often
such people cannot force the political and economic elite to make massive
changes in policy. If “we” means the rich and powerful, then the statements
are even more likely to be false, because these people have only to say, “No,
we don’t have to. We are in power, and no one can make us change — certainly
not silly book-scribblers.”

There may be something resembling sustainability, depending partly on one’s
definitions, but it would have little to do with the simplistic concepts that
are usually put forward. In the first place, there is nothing “natural” about
agriculture. Agriculture has only been practiced for about ten percent of the
entire history of Homo sapiens, and in that sense it is still an experiment
with uncertain results. To plow the earth is to “go against Nature,” since it
means disturbing the soil, the intricate, complex surface of the planet. Even
the slightest and shallowest disturbance causes chemical and biological
losses of various sorts. Yet in some countries one can drive for days without
seeing an end to cultivated land (or, of course, concrete and asphalt).
Almost no attention is paid to the final consequences of such practices, and
the relentless quest for money makes it unlikely that serious attention will
ever be paid. Even on a theoretical level, the permanent feeding of humanity
is not simple. Any long-term solution would require paying as much attention
to restoration of the land as has previously been paid to its cultivation.

Secondly and more importantly, to maintain a permanent balance between
population and cultivation would require a considerable reduction in the
former. It is foolish to say that the gap between food and population can be
met by increasing the production of food. The error, a rather obvious one, is
that an increase in food is inevitably followed by a further increase in
population, which in turn leads to another shortage of food. Since the dawn
of the human race, people have been trying to find ways to increase the food
supply; often they have succeeded. Perhaps the biggest success of all was
agriculture itself, the discovery that one can deliberately put seeds into
the ground and foster their growth, rather than going off into the jungle to
look for plants growing in the wild. That particular revolution led to a
great increase in human population. The original problem, however, simply
recurred. The solution (some means of increasing food) always leads straight
back to the original problem (an excess population).

But these two forces do not act merely in a circular fashion. It would be
more exact to say that they act as an ever-widening spiral. If we double the
food supply, and thereby induce a doubling of human population, the new
problem (that of excessive population) is not entirely identical to the
original problem, because as the spiral widens it creates further dangers.

At some point, we push the planet Earth to the point where it can no longer
maintain that spiral. We can convert vast quantities of petrochemicals into
fertilizers and pesticides, we can draw water out of the deepest aquifers and
even desalinate the oceans, but at some point we have to face the fact that
the Earth is only a small rock, small enough that it can be encircled by a
jet plane in a matter of hours. We are squeezing both our residential areas
and our farmlands beyond endurance. The greatest danger of such a spiral is
that when it breaks, it will do so in a far more destructive way than if the
problem had been solved earlier. When the human race suddenly finds itself
unable to manage the reciprocity of overpopulation and food production, there
will be no more choices left to make.

References

1. Brengle, K.G. Principles and Practices of Dryland Farming. Boulder,
Colorado: Colorado Associated University Press, 1982.

2. Carter, Vernon Gill, and Tom Dale. Topsoil and Civilization. Rev. ed.
Norman, Oklahoma: U of Oklahoma P, 1981.

3. Driver, Harold E. Indians of North America. 2nd ed. rev. Chicago:
University of Chicago Press, 1961.

4. King, F.H. Farmers of Forty Centuries, or, Permanent Agriculture in China,
Korea and Japan. Various editions.

5. McMahon, Kathy. “Remember, Remember the 5th of September, 2000.” Peak Oil
Blues. www.peakoilblues.com

6. Solomon, Steve. Water-Wise Vegetables. Seattle: Sasquatch, 1993.


Peter Goodchild is the author of Survival Skills of the North American
Indians, published by Chicago Review Press. His email address is odonatus
[at] live.com.





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