recently Professor Pimentel rounded up 22 esteemed colleagues --
also top researchers in each of their fields -- and compiled an
awesome work of breathtaking scope called Ecological Integrity:
Integrating Environment, Conservation and Health (Island Press,
Washington DC, Jan. 2001)
Among the many very appealing facets of Professor Pimentel is that
he is reasonably accessible and willing to discuss his methods,
his sources of data, and how he or his learned colleagues came up
with various calculations. At least he has been with inquiries from
VegSource. This stands in stark contrast to the "corporate"
scientists -- those who appear to work chiefly to enhance corporate coffers
by obfuscating issues, muddying waters and downplaying real risks
-- who are often unreachable or unwilling to comment or clarify,
or even defend, their questionable work. (For more on how
industry "scientists" often promote highly questionable,
discredited - or sometimes non-existent - studies to try to minimize
the seriousness of environmental problems, see our earlier article
on what celebrated Stanford Professor Paul Ehrlich terms "brownlash."
Opens new browser.)
Land Use and Animal Agriculture
With the assistance of Robert Goodland, Ph.D. (who is currently
the Enviromental Adviser to the World Bank, where he received Presidential
Excellence Awards in 1998 and 1999), Professor Pimentel provides
insight into land use for food.
shown in the table at right, Goodland and Pimentel cite data which
show that worldwide, food and fiber crops are gown on 12 percent
of the Earth's total land area. Another 24 percent of the land is
used as pasture to graze livestock that provide meat and milk products,
while forests cover an additional 31 percent. The small percentage
of forest and grassland set aside as protected national parks to
conserve biological diversity amounts to only 3 precent of the total
terrestrial ecosystem. Most of the remaining one-third of land area
is unsuitable for crops, pasture, and forests because it is too
cold, dry, steep, stony, or wet, or the soil is too infertile or
shallow to support plant growth.
The researchers point out that currently, a total of 3,265 pounds
of agricultural products (including feed and grains) are produced
annually to feed each American, while China's food supply averages
only 1,029 pounds/capita/year. The world average value is 1,353
pounds/capita/year. The low number for China correlates with a vegetarian
diet, the researchers point out, noting that most people in China
eat essentially a vegetarian diet.
Goodland and Pimentel believe that the present and future availability
of adequate supplies of fresh water is frequently taken for granted.
Natural collectors of water such as rivers and lakes vary in distribution
throughout the world and are frequently shared within and between
countries. All surface water supplies, but especially those in arid
regions, are diminished by evaporation. For insance, reservoir water
experiences an average yearly loss of about 24 percent.
All vegetation requires and transpires massive amounts of water
during the growing season. For example, a corn crop that produces
about 6616 pounds/acre of grain will take up and transpire about
534,600 gallons/acre of water during the growing season. To supply
this much water to the crop, not only must 855,119 gallons of rain
fall per acre, but also a significant portion must fall during the
The renowned scientists state that perhaps the greatest threat
to maintaining freshwater supplies is overdraft of surface and groundwater
resources used to supply the needs of the rapidly growing human
population and the agriculture that provides its food. Agricultural
production "consumes" more fresh water than any other
human activity. Worldwide, about 82 percent of the fresh water that
is pumped is "consumed" (so that it is nonrecoverable)
by agriculture. In the U.S., this figure is about 85 percent. All
people require a minimum of 24 gallons/day for cooking, washing,
and other domestic needs, while each American uses about 106 gallons/day
for domestic needs. Add to that a 1/4-pounder with cheese, and you've
added more than 3,000 additional gallons of water to your
daily consumption. About 80 nations in the world are already experiencing
significant water shortages. For instance, in China, more than three
hundred cities are short of water and the problem is intensifying.
Surface water in rivers and lakes and groundwater provide the freshwater
supply for the world. However, groundwater resources are renewed
at various rates but usually at the extremely slow rate of 0.1 -
0.3 percent per year. Because of their slow recharge rate, groundwater
resources must be carefully managed to prevent overdraft.
Yet humans are not effectively conserving groundwater resources,
the researchers note, and their overdraft is now a serious problem
in many parts of the world. Goodland and Pimentel cite several examples
worldwide to support this assertion. Most notably, they state that
in the vast U.S. Ogallala aquifer, annual overdraft is 130 to 160
percent above the replacement level. If this continues, this vital
aquifer is expected to become nonproductive in about 40 years. High
consumption of surface and groundwater resources is beginning to
limit the option of irrigating arid regions. Furthermore, the scientists
cite research showing that per capita irrigation area is also declining
because of salinization and waterlogging, both deleterious effects
of continual irrigation.
Throughout the book, Pimentel and his colleagues focus on the concept
of environmental sustainability. A big part of that equation, they
note, is to reduce demand for food, overall:
Reducing demand can be achived by eating more efficiently
on the food chain. Diet matters: environmental sustainability (ES)
can be brought about by reducing feeding inefficiencies, such
as those existing in producing grain-fed livestock, and encouraging
more efficient diets, such as plant-based ones.
The researchers note that the acceptability of plant-based diets
is a matter of degree, and that human societies differ in what diet
they find comfortable. Among those who restrict their consumption
of animal-based foods, there is a continuum from eschewing red met,
then "white" meat (poultry), then mammals or all terrestrial
aniamls. Some will eat cold-blooded animals but not warm-blooded
ones (i.e., some people eat fish, but not rabbits or chickens).
The figure above shows the environmental sustainability ratings
for where people eat on the food chain, and a proposed tax logic
to reflect the true environmental cost for various foods.
In their book, the researchers make detailed and virtually unassailable arguments
to support their wise conclusions on how we can achieve long-term
sustainability and integrity in agriculture:
- Most people of the world -- those already at the efficient,
low-impact end of the food chain -- would stay at the low end
of the chain, but would diversify their diet;
- Affluent people now eating at the top of the food chain would
pay full costs of their high-impact food choices, consonant with
the "polluter pays" principal, via food taxation for
those foods depleting resources at very high rates -- or elect
to consume more efficiently lower down the food chain;
- People starting to move up the food chain (e.g., in China and
India) would be encouraged to stop where they are -- and to consider
moving back down the chain.
Pimentel and Goodland note that incentives are needed to promote
grain-based diets by applying good economics and good environmental
management to food and agriculture. In particular, conversion efficiency
and "polluter pays" principals should be used in setting
full-price policies, which internalizes environmental and social
costs. They note that cattle feedlots and slaughterhouses consume
much water and generate much highly polluting waste. Wastes often
are not efficiently reused but are instead disposed of in the nearest
watercourse. Feed and forage production consume even more water.
These costs need to be internalized.
In the researchers' view, the highest taxes would fall on the least
efficient converters, namely hogs and cattle. Slightly lower taxes
would be assessed on sheep and those cattle grazing natural grassland.
No taxes would be paid on grains (rice, maize, wheat, buckwheat),
starches (potatoes, cassava), and legumes (soy, pulses, beans, peas,
peanuts). Modest subsidies on coarse grains (millet, pearl millet,
sorghum) would alleviate hunger and are unlikely to be abused (as
the rich usually won't eat such foods).
Encouragement for domestic or village-scale beneficiation, such
as of peanuts to peanut butter and cashew fruits to roasted nuts,
often doubles or triples the profit to the grower. Peanut butter
and cornflakes were invented expressly to increase the consumption
of those low-impact foods at the bottom of the food chain.
The authors conclude that "Adoption of such policies will
not solve world hunger overnight, but it will certainly help."
If you are looking for a comprehensive discussion of food choices
and ecological sustainability, head for your local or online bookstore
and pick up a copy of Ecological Integrity: Integrating Environment,
Conservation and Health. Written in a scholarly style by some
of our current greatest thinkers, this work is filled with valuable
facts, figures and loads of references to many other important works,
and is an invaluable addition to any ecologist's library.
See also How
Much Water to Make One Pound of Beef?
William Harris, MD, comments on Professor Pimentel's suggestion
to tax meat and dairy in order to reflect the real environmental
and health costs:
I have never
met David Pimentel but have always admired his work. I corresponded
with Robert Goodland at the time the World Bank was floating the
China-Smallholder Cattle Development Project and think we're lucky
to have him on our side.
As for taxing
meat I see pros and cons.
there's nothing politicians like better than levying new taxes
that they can run through their greedy fingers, so the pols might
go for it.
we'll never see the end of alcohol and tobacco because taxing
them provides huge revenues to the government. Taxing meat might
have the same effect.
If I were
carrying the ball on this I'd go for an across the board final and
complete end to all USDA subsidies, price supports, and "production
flexibility contracts" which would save the taxpayers a lot of money.
I don't like
to encourage more taxes for anyone and as a libertarian I support
the right of the individual to cut his own throat with the razor
of his choice as long as my taxes don't pay for the razor and the
guy's medical bills. That way his bad choices have their own unshielded
bad consequences and eventually he may come to his senses. We'd
be telling the meat folks that we're not the national nanny and
that they're free to raise and sell their stuff for whatever the
market will bear, but that we're not going to give them yearly bailouts
when profits don't meet their expectations, we're not going to pay
for their feed grains, pay their public lands grazing fees, shoot
their predators for them, and let the Rubes think meat is cheap
when their own taxes have already paid half the meat bill. Then
I'd insist that the IRS stop requiring that citizens pay a third
of the animal food advertising expenses. Under those conditions
I think the $.99 hamburger would disappear fairly soon and consumers
would suddenly discover an appetite for the healthy vegetables and
fruits that don't get much help from the USDA and the IRS in the