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A dystopia in the making, the global warming scenario is inspiring solutions straight from the pages of science fiction novels. One proposal would harness the power of the ocean to suck carbon dioxide from the atmosphere, either by tinkering with the oceans' ecological systems or by mechanically pumping liquefied carbon thousands of feet below the surface.
Advocates of "sequestration" argue that the ocean already functions as the world's largest carbon sink: it contains 50 times more carbon dioxide than the atmosphere, most of which is stored in sediments on the ocean floor. By enhancing the oceans' natural ability to trap CO2, the logic goes, we would dramatically reduce the amount of the greenhouse gas in the atmosphere.
Specifically, marine scientists are trying to figure out ways of multiplying the number of phytoplankton, the oceans' photosynthesizing organisms. To date, the only theory that has really been tested is something jokingly called "the Geritol solution." In 1995, a team of scientists was able to demonstrate that adding iron to waters near the Galapogos Islands doubled the amount of plankton and quadrupled its growth rate (see "Anemic Oceans," In Brief, March/April 1997). Exhilaration, however, was shortlived: The effect lasted only a day and the amount of carbon dioxide removed was far less than expected.
"It was a great science experiment," says Darren Goetze, a staff scientist at the Union of Concerned Scientists. "But by no means is this a reasonable way to get rid of atmospheric carbon dioxide." The ecological impact alone, says Goetze, is cause for rejecting iron fertilization. "Everything we know tells us these kinds of technological fixes don't work," he adds. "You can't increase the amount of one nutrient without affecting the entire marine food chain."
In the meantime, engineers and energy experts are masterminding schemes to liquefy carbon dioxide as it is released from power plants, and pump it into the deep ocean. "We're at the very beginning stages of research," says Howard Herzog of Massachusetts Institute of Technology's Energy Lab. "We feel there are ways to design ocean disposal strategies with near-zero environmental impacts." In a paper written last year, Herzog and his team concluded that the best approach would be to tow a pipe from a moving ship and inject carbon dioxide at depths of half a mile. Another solution involves creating a carbon lake by pumping liquid carbon dioxide into a deep ocean trench.
Apart from the billions of dollars such engineering feats are expected to cost, ocean storage is at best a temporary solution; over a period of 500 years or so, the carbon dioxide would eventually circulate back into the atmosphere, experts say. But the real problem, argue critics, is that sequestration treats the symptoms, not the cause.
"People are using it as an excuse not to reduce fossil fuel usage," says Goetze. "What we need to be doing is putting our money toward developing renewable energy sources and reducing global CO2 emissions."
CONTACT
Union of Concerned Scientists
2 Brattle Square
Cambridge, MA 02238
Tel: (617) 547-5552
--Linda Baker
Eco-Archaeology: Forward into the Past
How did the ancient Maya do it? While today a few hundred thousand descendants of the Maya survive with difficulty, the ancient community of two million developed a subsistence economy and a sophisticated political framework without destroying the rainforest for over 13 centuries.
"Old school" scientists still spend most of their time unearthing core sites and deciphering hieroglyphs. The new breed of "evolutionist" archaeologists got their start in the 1960s by investigating large areas around dig sites (their "suburbs," so to speak), studying human interaction at all strata of society and gathering plant and animal evidence. The practice is known as eco-archaeology.
"How a particular society adapts and relates to its environment helps explain why it has a particular size or form," says Dr. Barbara Price, a professor of anthropology at Columbia University. She adds that excavating tombs and temples can only go so far to explain the rise and fall of a civilization. Other important factors are "what constituted a household, how did the population make a living, and how was land distributed."
Monumental projects like the Mayan temples, the pyramids of Egypt or England's Stonehenge were built by complex societies, eco-archaeologists say, with a practical organization of labor, productive farmlands, and industries that sustainably produced building materials.
The practical application of eco-archaelogy is epitomized at El Pilar, the recently discovered and monumental Maya site straddling Belize and Guatemala. "The ancient Maya were an agricultural society," stresses Dr. Anabel Ford, El Pilar project director and head of the University of California's MesoAmerica Research Center, "and their achievements depended upon the success of their farmers." In excavating ancient houses, garden plots, cooking pots and cutting tools, the El Pilar project emphasizes the way most of the populace lived, not just the tiny elite that ruled them.
The ancient Maya practiced extensive polyculture, yielding long-term results by combining crops of maize, beans, cacao, fruit trees, medicinal plants, palms, cotton and tobacco. By this process, Dr. Ford says, they were mimicking the rejuvenating qualities of the forest in a human environment, without depleting their land, setting fires or polluting rivers. At El Pilar, the humble adobe homes surrounding the main sites will be resurrected to give a more complete picture of daily life. Sustainable resource management programs will focus on the "forest garden," which sustained the Maya for centuries.
John Bennett, Distinguished Scholar in Residence at Washington University in St. Louis, says the new field is an opportunity to see beyond scientific myopia, which slots academics into their own narrow disciplines. There's more to archaeology, he says, than unearthing royal tombs and deciphering hieroglyphs.
CONTACT
MesoAmerican Research Center
c/o The Institute for Social Behavioral and Economic Research
University of California at Santa Barbara, CA 93106-2150
Tel: (805) 893-8191
--Brigitte Bertrou Seligman
The Monarchs' Perilous Flight
Until 1976, the Monarch butterfly's winter migration site was one of life's enduring mysteries. In that year, the 40-year quest of a Canadian zoologist ended in a dramatic payoff in Mexico's transvolcanic mountain range: A butterfly-laden branch cracked and fell, revealing a single specimen bearing a wing tag: "Return to Museum of Zoology, Toronto, Ont."
His electrifying "Aha!" came as millions of orange, yellow, white and black butterflies clung to every branch and tree trunk for 300 feet in all directions. But today the southern nesting grounds of the world's most numerous, furthest-migrating butterfly are under siege.
The Monarch's eye-catching migration begins in southern Canada, where millions cross Lake Erie at Point Pelee National Park each fall. Park spokeswoman Tammy Dobbie estimates that 20,000 of the park's 44,000 annual visitors come to see the Monarch, for which the Canadian government provides three protected nesting areas.
At the other end of the migration, the Monarch fares less well. Mexican campesinos harvesting the Oyamel trees on which Monarchs nest are fast overpowering a feeble conservation effort in Mexico's five sanctuaries. Scientists are advancing strategies ranging from outright seizure of the land to stimulating ecotourism.
The habitat is indeed endangered, contends Professor David Gibo, a zoologist at the University of Toronto at Mississauga, "but the Monarch is doing just fine. There's a tendency to overstate the situation, forgetting the Monarch is a bug, and each female can produce 500 eggs. So if 498 die and only two survive, you have a stable population."
But Professor Orley "Chip" Taylor, director of Monarch Watch at the University of Kansas, fears a long-term threat. "The forest has to be made valuable for local people," says Taylor. "Ecotourism is one way to do this, but it hasn't helped enough. These communities are in very dire straits."
From November to March, thousands of Mexicans flock on weekends to a government-run butterfly visitor center in Michoacan state. The small admission fee goes to indigenous landowner groups called ejidos. But Taylor doubts that the fees are providing enough income. "Ecotourism revenues are limited to two of 11 of the major nesting sites," he says. "There are 54 ejidos in the region, and only four are directly benefiting from tourism" (while all are being asked to forgo logging).
What's needed, says Taylor, is a 40-year plan for forest management that focuses on "how resources can be extracted from the environment to support people." But time may be running out, and an international conference last fall failed to find a workable solution. Some experts give the Monarchs' wintering site only a decade or two.
CONTACT
Monarch Watch
Department of Entomology
Haworth Hall
University of Kansas
Lawrence, KS 66045
Tel: (888) TAGGING
--Paul Gainor
Snap, Crackle and Flop
Slaughter of the innocents: a bug zapper does its grizzly work.
© Ted Rose / Unicorn Stock Photos
Zzzt. Zzzt. Zap. That's the sound of your electric mosquito zapper in action, killing the little blood suckers--or at least that's what you think it's doing. Unfortunately, those snap, crackle and pops are electrocuting just about every other non-biting insect instead. University of Delaware entomology professor Doug Tallamy and his students recently picked through the fried remains of six bug zappers, and of 14,000 electrocuted bugs, only 31 were biting insects. "Believe it or not, mosquitoes are not my area of research," says Tallamy. "I was convinced the traps didn't work and wanted to know just how bad they were." Much the same results were obtained by a team of Dateline NBC investigators, which sifted through 10,000 carcasses--one night's haul--and found only eight mosquitoes. With around four million zappers working nights in the U.S., nearly 71 billion innocent insects are getting toasted each month.
Insect biologist Phil Pellitteri says the electric zappers emit ultraviolet light to attract mosquitoes. But these pesky insects aren't attracted to light. Instead, they hone in on carbon dioxide from our breath and, at close range, heat from our bodies, to find their meals. "Sometimes we talk about a revenge factor--people hear these things getting fried, and they think that they're killing mosquitoes," says Pellitteri. In reality, "they're killing lots of things that aren't mosquitoes." The most common bugs zapped are beetles, moths, flies, bees, ants, wasps and termites, many of which are beneficial for pollination and invasive insect control.
Tallamy explains that the non-target insects being killed comprise important components of aquatic and terrestrial food chains. "There is no such thing as a healthy ecosystem without insects," he says. Unfortunately, most homeowners consider all insects to be bad.
According to a lively online forum at the GardenWeb site, the death toll in other insects can be reduced by putting a fine mesh screen--big enough for mosquitoes to pass through, but not bigger bugs--around the zapper. Turning the miniature death chamber off during the daytime helps, too. Another alternative is putting up a bat house, since a single bat can devour thousands of mosquitoes each evening.
A new generation of heat- and CO2-emitting zappers is currently being developed. In tests, mosquitoes love 'em, and other bugs leave 'em alone. Says Tallamy, "Whether a homeowner is willing to pay a lot of money for a trap that only occasionally goes zap is anybody's guess."
CONTACT
Entomological Society of America
9301 Annapolis Road
Lanham, MD 20706-3115
tel: (301) 731-4535
--Wendee Holtcamp
Sowing the Seeds of Change
"Organics are extremely important for the future of the planet in terms of healthy soil and clean water," says Stephen Badger, president of the Santa Fe, New Mexico-based Seeds of Change, a mail order organic seed company. "It's farming in a way that is not detrimental to the ecosystem. Ultimately, it's something that we simply need to do for the health of our children and grandchildren."
According to Howard Shapiro, Seeds of Change's vice president of agriculture, conventionally produced seeds require enormous amounts of chemical pesticides, herbicides, fungicides and fertilizers. "If you turn a blind eye to this, you've lost the whole point," he says.
Ironically, the law allows chemically-produced seeds to be used to grow certified organic crops. That, says Jay Feldman, head of the National Coalition Against the Misuse of Pesticides, "betrays the system of agriculture inherent in the word 'organic'--a system that is respectful of the environment and protective of human health and wildlife."
Seeds of Change is the only company selling certified organic seeds on a national basis, but many other companies are involved locally. "Most seed companies do not grow their own seeds," Badger points out, "because it's very, very difficult. Growing seeds is probably one of the most complex agricultural tasks known."
Each seed variety must go through the arduous process of cleansing, testing, and storage, and there are many unpredictable elements, Badger explains. He recalls being just days away from a harvest of lettuce seeds when a flock of finches flew in under cover of darkness and ate everything. Weather, too, tends to wreak havoc on the harvests, and a poorly timed deluge can wipe out an entire crop. Avoiding disaster requires growing seeds of the same variety in several different locations. The company also hordes a backup supply of seeds for emergency use.
"Bad agricultural practices can end up polluting your water and your family," says Shapiro. "But a garden is supposed to be Eden in many ways, and that's what we're trying to help happen."
CONTACTS
National Coalition Against the Misuse of Pesticides
530 7th Street SE
Washington, DC 20003
Tel: (202) 543-5450
Seeds of Change
PO Box 15700
Santa Fe, NM 87506-5700
Tel: (888) 762-7333
--Chris Hayhurst
CONTACTS
Seeds of Change
PO Box 15700
Santa Fe, NM 87506-5700
Phone: (888) 762-7333
National Coalition Against the Misuse of Pesticides
530 7th Street SE
Washington, DC 20003
Phone: (202) 543-5450
Entomological Society of America
9301 Annapolis Road
Lanham, MD 20706-3115
Phone: (301) 731-4535
Monarch Watch
Department of Entomology
Haworth Hall
University of Kansas
Lawrence, KS 66045
Phone: (888) TAGGING
MesoAmerican Research Center
c/o The Institute for Social Behavioral and Economic Research
University of California at Santa Barbara, CA 93106-2150
Phone: (805) 893-8191
Union of Concerned Scientists
1616 P Street NW
Suite 310
Washington, DC 20036
Phone: (202) 332-0900
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