According to FAO,
livestock is responsible for the 18% of the greenhouse gas emissions, while
only 13% is due to transport.
El lunes sin carne de
McCartney, EFE / ELPAÍS.com - Londres / Madrid - 15/06/2009.
with worldwide production of milk and beef expected to double in the next 30
years, the United Nations has called livestock one of the
most serious near-term threats to the global climate. In a 2006 report that
looked at the environmental impact of cows worldwide, including forest-clearing
activity to create pasture land, it estimated that cows might be more dangerous
to Earth’s atmosphere than trucks and cars combined.
Greening the Herds: A New Diet to Cap Gas, by Leslie Kaufman, June 5,
2009, New York Times.
EFE / ELPAÍS.com - Londres / Madrid - 15/06/2009
Uno de los vegetarianos más famosos del mundo, Paul
McCartney, se ha sumado a una campaña internacional que recomienda que la gente
renuncie algún día de la semana al consumo de carne para combatir el cambio
climático: Lunes sin carne.
El ex Beatle y sus hijas, Stella y Mary, intentan
persuadir a los consumidores para que adopten una dieta vegetariana al menos un
día a la semana, con el objetivo de reducir las emisiones de gas invernadero de
la cabaña mundial, que contribuyen de modo significativo al peligroso
calentamiento del planeta.
La familia McCartney ha conseguido apoyo de personalidades del mundo del
espectáculo, la empresa y la ciencia, como los actores Kevin Spacey, Woody Harrelson y Joanna Lumley, el cantante Chris Martin y el empresario Richard Branson,
fundador de la aerolínea Easyjet.
"Deberíamos preocuparnos por el cambio climático porque, si no lo
hacemos, vamos a dejarles en herencia a nuestros hijos y a los hijos de éstos
un problema gravísimo", ha advertido McCartney al periódico británico The Independent. Y
es que los ecologistas están preocupados por el impacto medioambiental de los
animales destinados a la alimentación humana y en concreto por la destrucción
de masas forestales en el Amazonas y otros lugares en beneficio de la
ganadería.
Las vacas emiten en sus regüeldos grandes cantidades del gas metano, que
supera en 21 veces el efecto invernadero del dióxido de carbono. De hecho,
según
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June 5,
2009, New York Times
HIGHGATE,
Libby, age 6, and the 74
other dairy cows on Guy Choiniere’s farm here are at
the heart of an experiment to determine whether a change in diet will help them
belch less methane, a potent heat-trapping gas that has been linked to climate
change.
Since January, cows at 15
farms across
As of the last reading in
mid-May, the methane output of Mr. Choiniere’s herd
had dropped 18 percent. Meanwhile, milk production has held its own.
The program was initiated
by Stonyfield Farm, the yogurt manufacturer, at the
“They are healthier,” he
said of his cows. “Their coats are shinier, and the breath is sweet.”
Sweetening cow breath is a
matter of some urgency, climate scientists say. Cows have digestive bacteria in
their stomachs that cause them to belch methane, the second-most-significant
heat-trapping emission associated with global warming after carbon dioxide. Although
it is far less common in the atmosphere than carbon dioxide, it has 20 times
the heat-trapping ability.
Frank Mitloehner,
a University of California, Davis, professor who places cows in air-tight tent
enclosures and measures what he calls their “eruptions,” says the average cow
expels — through burps mostly, but some flatulence — 200 to
More broadly, with
worldwide production of milk and beef expected to double in the next 30 years,
the United Nations has called livestock one of the
most serious near-term threats to the global climate. In a 2006 report that
looked at the environmental impact of cows worldwide, including forest-clearing
activity to create pasture land, it estimated that cows might be more dangerous
to Earth’s atmosphere than trucks and cars combined.
In the United States, where
average milk production per cow has more than quadrupled since the 1950s, fewer
cows are needed per gallon of milk, so the total emissions of heat-trapping gas
for the American dairy industry are relatively low per gallon compared with
those in less industrialized countries.
Dairy Management Inc., the
promotion and research arm of the American dairy industry, says it accounts for
just 2 percent of the country’s emissions of heat-trapping gases, most of it
from the cows’ methane.
Still, Erin Fitzgerald,
director of social and environmental consulting for Dairy Management, says the
industry wants to avert the possibility that customers will equate dairies
with, say, coal plants. It has started a “cow of the future” program, looking
for ways to reduce total industry emissions by 25 percent by the end of the
next decade.
William R. Wailes, the head of the department of animal science at Colorado State University who is working on the cow of the
future, says scientists are looking at everything from genetics — cows that
naturally belch less — to adjusting the bacteria in the cow’s stomach.
For the short run,
Professor Wailes said, changes in feed have been the
most promising.
Stonyfield Farm, which started as a
money-raising arm for a nonprofit organic dairy
school and still has a progressive bent, has been working on the problem longer
than most.
Nancy Hirshberg,
Stonyfield’s vice president for natural resources,
commissioned a full assessment of her company’s impact on climate change in
1999 that extended to emissions by some of its suppliers.
“I was shocked when I got
the report,” Ms. Hirshberg said, “because it said our
No. 1 impact is milk production. Not burning fossil fuels for transportation or
packaging, but milk production. We were floored.”
From that moment on, Ms. Hirshberg began looking for a way to have the cows emit
less methane.
A potential solution was
offered by Groupe Danone,
the French makers of Dannon yogurt and Evian bottled
water, which bought a majority stake in Stonyfield
Farm in 2003. Scientists working with Groupe Danone had been studying why their cows were healthier and
produced more milk in the spring. The answer, the scientists determined, was
that spring grasses are high in Omega-3 fatty acids, which may help the cow’s
digestive tract operate smoothly.
Corn and soy, the feed
that, thanks to postwar government aid, became
dominant in the dairy industry, has a completely different type of fatty acid
structure.
When the scientists began
putting high concentrations of Omega-3 back into the cows’ food year-round, the
animals were more robust, their digestive tract functioned better and they
produced less methane.
The new feed is used at 600
farms in
A reason farmers like corn
and soy is that those crops are a plentiful, cheap source of energy and protein
— which may lead some to resist replacing them. But Ms. Laurain
said flax cost less than soy, although grain prices can fluctuate. The flax
used in the new feed is grown in
If the pilot program was
expanded, she said, a heating facility would be built in the
Ms. Laurain
maintains that even if the feed costs more, it yields cost savings because the
production of milk jumps about 10 percent and animals will be healthier, live
longer and produce milk for more years.
The methane-reduction
results have been far more significant in France than in the Vermont pilot —
about 30 percent — because the feed is distributed there not just to organic
farms, where the animals already eat grass for at least half the year, but also
to big industrial farms.
Farms in the Vermont
program, like Mr. Choiniere’s, are also relying on Valorex’s method for measuring methane reduction, which
involves analyzing fatty acids in the cows’ milk. Professor Wailes,
of
Mr. Choiniere
said that regardless of how the tests turned out, he planned to stick with the
new feeding system.
“They are
healthier and happier,” he said of his cows, “and that’s what I really care
about.”