[Digestion] Biogas conversation rates

Reuben Deumling 9watts at gmail.com
Wed Jan 19 14:15:28 CST 2011


On Wed, Jan 19, 2011 at 12:04 PM, bingham <bingham at zekes.com> wrote:

>
> subsidized grains....under cut the production of corn ???? I would like to
> see the evidence of a subsidized grain effecting the production of corn in a
> third world setting. Most third world farmers, only cost, is the seed. Rain
> is free and the grass is free, to feed there beasts of burden is free. They
> do not use energy.
>

Your logic is a bit tricky to follow, but here's something to ponder in
relation to your notion that agriculture in the third world is (nearly) free
and does not use energy.

-----Forwarded Message-----
From: Earth Policy Release
Sent: Jan 14, 2011 2:00 AM
To: mcat at teleport.com
Subject: Earth Policy Release -- The Great Food Crisis of 2011

 [image: Earth Policy Institute] <http://www.earth-policy.org/>
  *THE GREAT FOOD CRISIS OF 2011*
*By Lester R. Brown
www.earth-policy.org/plan_b_updates/2011/update90

 Earth Policy Release
Plan B Update
January 14, 2011
*
*
 As the new year begins, the price of wheat is setting an all-time high in
the United Kingdom. Food riots are spreading across Algeria. Russia is
importing grain to sustain its cattle herds until spring grazing begins.
India is wrestling with an 18-percent annual food inflation rate, sparking
protests. China is looking abroad for potentially massive quantities of
wheat and corn. The Mexican government is buying corn futures to avoid
unmanageable tortilla price rises. And on January 5, the U.N. Food and
Agricultural organization announced that its food price index for December
hit an all-time high.

But whereas in years past, it's been weather that has caused a spike in
commodities prices, now it's trends on both sides of the food supply/demand
equation that are driving up prices. On the demand side, the culprits are
population growth, rising affluence, and the use of grain to fuel cars. On
the supply side: soil erosion, aquifer depletion, the loss of cropland to
nonfarm uses, the diversion of irrigation water to cities, the plateauing of
crop yields in agriculturally advanced countries, and—due to climate change
—crop-withering heat waves and melting mountain glaciers and ice sheets.
These climate-related trends seem destined to take a far greater toll in the
future.

There's at least a glimmer of good news on the demand side: World population
growth, which peaked at 2 percent per year around 1970, dropped below 1.2
percent per year in 2010. But because the world population has nearly
doubled since 1970, we are still adding 80 million people each year.
Tonight, there will be 219,000 additional mouths to feed at the dinner
table, and many of them will be greeted with empty plates. Another 219,000
will join us tomorrow night. At some point, this relentless growth begins to
tax both the skills of farmers and the limits of the earth's land and water
resources.

Beyond population growth, there are now some 3 billion people moving up the
food chain, eating greater quantities of grain-intensive livestock and
poultry products. The rise in meat, milk, and egg consumption in
fast-growing developing countries has no precedent. Total meat consumption
in China today is already nearly double that in the United States.

The third major source of demand growth is the use of crops to produce fuel
for cars. In the United States, which harvested 416 million tons of grain in
2009, 119 million tons went to ethanol distilleries to produce fuel for
cars. That's enough to feed 350 million people for a year. The massive U.S.
investment in ethanol distilleries sets the stage for direct competition
between cars and people for the world grain harvest. In Europe, where much
of the auto fleet runs on diesel fuel, there is growing demand for
plant-based diesel oil, principally from rapeseed and palm oil. This demand
for oil-bearing crops is not only reducing the land available to produce
food crops in Europe, it is also driving the clearing of rainforests in
Indonesia and Malaysia for palm oil plantations.

The combined effect of these three growing demands is stunning: a doubling
in the annual growth in world grain consumption from an average of 21
million tons per year in 1990-2005 to 41 million tons per year in 2005-2010.
Most of this huge jump is attributable to the orgy of
investment<http://www.earth-policy.org/plan_b_updates/2007/update63>in
ethanol distilleries in the United States in 2006-2008.

While the annual demand growth for grain was doubling, new constraints were
emerging on the supply side, even as longstanding ones such as soil erosion
intensified. An estimated one third of the world's cropland is losing
topsoil faster than new soil is forming through natural processes—and thus
is losing its inherent productivity. Two huge dust bowls are forming, one
across northwest China, western Mongolia, and central Asia; the other in
central Africa. Each of these dwarfs the U.S. dust bowl of the 1930s.

Satellite images show a steady flow of dust storms leaving these regions,
each one typically carrying millions of tons of precious topsoil. In North
China, some 24,000 rural villages have been abandoned or partly depopulated
as grasslands have been destroyed by overgrazing and as croplands have been
inundated by migrating sand dunes.

In countries with severe soil erosion, such as Mongolia and Lesotho, grain
harvests are shrinking as erosion lowers yields and eventually leads to
cropland abandonment. The result is spreading hunger and growing dependence
on imports. Haiti and North Korea, two countries with severely eroded soils,
are chronically dependent on food aid from abroad.

Meanwhile aquifer depletion is fast shrinking the amount of irrigated area
in many parts of the world; this relatively recent phenomenon is driven by
the large-scale use of mechanical pumps to exploit underground water. Today,
half the world's people live in countries where water tables are falling as
overpumping depletes aquifers. Once an aquifer is depleted, pumping is
necessarily reduced to the rate of recharge unless it is a fossil
(nonreplenishable) aquifer, in which case pumping ends altogether. But
sooner or later, falling water tables translate into rising food prices.

Irrigated area is shrinking in the Middle East, notably in Saudi Arabia,
Syria, Iraq, and possibly Yemen. In Saudi Arabia, which was totally
dependent on a now-depleted fossil aquifer for its wheat self-sufficiency,
production is in a freefall. From 2007 to 2010, Saudi wheat production fell
by more than two thirds. By 2012, wheat production will likely end entirely,
leaving the country totally dependent on imported grain.

The Arab Middle East is the first geographic region where spreading water
shortages are shrinking the grain harvest. But the really big water deficits
are in India, where the World Bank numbers indicate that 175 million people
are being fed with grain that is produced by overpumping. In China,
overpumping provides food for some 130 million people. In the United States,
the world's other leading grain producer, irrigated area is shrinking in key
agricultural states such as California and Texas.

The last decade has witnessed the emergence of yet another constraint on
growth in global agricultural productivity: the shrinking backlog of
untapped technologies. In some agriculturally advanced countries, farmers
are using all available technologies to raise yields. In Japan, the first
country to see a sustained rise in grain yield per acre, rice yields have
been flat now for 14 years. Rice yields in South Korea and China are now
approaching those in Japan. Assuming that farmers in these two countries
will face the same constraints as those in Japan, more than a third of the
world rice harvest will soon be produced in countries with little potential
for further raising rice yields.

A similar situation is emerging with wheat yields in Europe. In France,
Germany, and the United Kingdom, wheat yields are no longer rising at all.
These three countries together account for roughly one-eighth of the world
wheat harvest. Another trend slowing the growth in the world grain harvest
is the conversion of cropland to nonfarm uses. Suburban sprawl, industrial
construction, and the paving of land for roads, highways, and parking lots
are claiming cropland in the Central Valley of California, the Nile River
basin in Egypt, and in densely populated countries that are rapidly
industrializing, such as China and India. In 2011, new car sales in China
are projected to reach 20 million—a record for any country. The U.S. rule of
thumb is that for every 5 million cars added to a country's fleet, roughly 1
million acres must be paved to accommodate them. And cropland is often the
loser.

Fast-growing cities are also competing with farmers for irrigation water. In
areas where all water is being spoken for, such as most countries in the
Middle East, northern China, the southwestern United States, and most of
India, diverting water to cities means less irrigation water available for
food production. California has lost perhaps a million acres of irrigated
land in recent years as farmers have sold huge amounts of water to the
thirsty millions in Los Angeles and San Diego.

The rising temperature is also making it more difficult to expand the world
grain harvest fast enough to keep up with the record pace of demand. Crop
ecologists have their own rule of thumb: For each 1 degree Celsius rise in
temperature above the optimum during the growing season, we can expect a 10
percent decline in grain yields. This temperature effect on yields was all
too visible in western Russia during the summer of 2010 as the harvest was
decimated when temperatures soared far above the norm.

Another emerging trend that threatens food security is the melting of
mountain glaciers. This is of particular concern in the Himalayas and on the
Tibetan plateau, where the ice melt from glaciers helps sustain not only the
major rivers of Asia during the dry season, such as the Indus, Ganges,
Mekong, Yangtze, and Yellow rivers, but also the irrigation systems
dependent on these rivers. Without this ice melt, the grain harvest would
drop precipitously and prices would rise accordingly.

And finally, over the longer term, melting ice sheets in Greenland and West
Antarctica, combined with thermal expansion of the oceans, threaten to raise
the sea level by up to six feet during this century. Even a three-foot rise
would inundate half of the riceland in Bangladesh. It would also put under
water much of the Mekong Delta that produces half the rice in Vietnam, the
world's number two rice exporter. Altogether there are some 19 other
rice-growing river deltas in Asia where harvests would be substantially
reduced by a rising sea level.

The current surge in world grain and soybean prices, and in food prices more
broadly, is not a temporary phenomenon. We can no longer expect that things
will soon return to normal, because in a world with a rapidly changing
climate system there is no norm to return to.

The unrest of these past few weeks is just the beginning. It is no longer
conflict between heavily armed superpowers, but rather spreading food
shortages and rising food prices—and the political turmoil this would lead
to—that threatens our global future. Unless governments quickly redefine
security and shift expenditures from military uses to investing in climate
change mitigation, water efficiency, soil conservation, and population
stabilization, the world will in all likelihood be facing a future with both
more climate instability and food price volatility. If business as usual
continues, food prices will only trend upward.

**NOTE: This piece originally appeared in Foreign
Policy<http://www.foreignpolicy.com/articles/2011/01/10/the_great_food_crisis_of_2011?page=0,3>on
Tuesday, January 10, 2011.
*

#   #   #

Lester Brown is President of the Earth Policy Institute and author of
*World on the Edge: How to Prevent an Environmental and Economic
Collapse*(New York: W.W. Norton & Company, 2011) available online at
www.earth-policy.org/books/wote.


Data, endnotes, and additional resources
can be found on www.earth-policy.org.
* Feel free to pass this information along to friends, family members, and
colleagues!*
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