The environment in the news tuesday, 30 May 2006

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By Tim Bowler

30.5.2006

Germany is the world's biggest user of wind power, and it has ambitious plans to build even more wind turbines.

It has decided that generating nuclear power is not the way forward, and it has decided eventually to close all the country's existing nuclear power stations.

The country's great hope for is for a future of green energy, and in particular wind power.

However, some observers are now questioning whether all the investment in wind power makes economic sense.

Growing demands

Alsleben is a small market town in eastern Germany on the banks of the Saale river.

It's a quiet place surrounded by rolling farmland, but for the past few weeks the people here have been getting used to some new neighbours.

On the hills above them are 37 giant wind turbines. Alsleben is now the site of one of the biggest wind farms in the country.

Close up the engineering is impressive. The blades for these wind turbines are longer than the wing of a Boeing 747 jumbo jet. They are all built in the shape of aerofoils, in order to withstand speeds of up to 270 km an hour.

The site is owned by the US industrial conglomerate, General Electric. It is convinced that wind energy makes economic sense. GE reckons the demand for wind power in other European countries will grow in the same way that it has in Germany.

Under the Kyoto Protocol, Germany is committed to cutting its greenhouse gas emissions. Wind power has obvious advantages as the electricity it generates is non-polluting.

Cost estimates challenged

Germany's politicians plan to have 20% of the country's energy coming from renewable sources like wind by 2020.

But a row is brewing over the cost of building the power lines which will be needed.

Germany's energy agency says this will cost 1.1bn euros ($1.4bn; £750m) or an extra 17 euros a year for each household.

But energy specialist Professor Wolfgang Pfaffenberger, of Bremen International University, says these figures are too low and it will be domestic customers who will foot the bill.

"It is a big problem for industrial users to pay these extra prices because other countries have cheaper energy. To keep the jobs here, and stop businesses from leaving, more of the costs will be pushed to the domestic sector."

Alsleben's new wind farm is designed to supply electricity to 30,000 homes, but when the wind stops blowing, the blades stop turning and the power output falls to zero.

Critics say this underlines one essential drawback: you can't depend on wind for energy. Even if you build wind farms you still need conventional power plants in case the wind fails.

"We face many hours a year with more or less no wind," says Martin Fuchs, chief executive of one of Germany's biggest electricity grid operators, E.On Netz. "We can save only a very small number of conventional power stations."

Surges of wind-generated electricity risk overloading the grid, he adds, causing power blackouts.

These are charges the wind power industry robustly rejects. Christian Kjaer, of the European Wind Energy Association, says all electricity grids are designed to cope with power fluctuations.

"Fossil fuel or nuclear power stations are truly intermittent," he argues. "You never see 1000 megawatts of wind energy shutting down in a second, yet that's what conventional power stations do."

For now, few in Germany are questioning the country's wind energy programme.

The savings in terms of greenhouse gas emissions are politically popular.

Yet there is a lingering question-mark over the cost of all this, and whether building so many wind turbines truly makes economic sense.

GERMANY'S 2020 ENERGY GOALS

20% of all energy to come from renewable sources

28,000 megawatts of power from onshore windfarms

20,000 megawatts of power from offshore windfarms in the Baltic and North Sea ____________________________________________________________________________

29.05.06

Die Bundesregierung begrüßt nach den Worten Merkels „dieses Projekt, weil Deutschland auch bei modernen Umwelttechnologien Weltspitze bleiben soll, die die Energieeffizienz erhöhen, den CO- Ausstoß verringern und damit unser Klima schützen“.

Die Anlage soll bei der Braunkohleverarbeitung nicht das Treibhausgas CO in die Atmosphäre abgeben. Sie arbeitet nach dem so genannten Oxyfuel-Verfahren. Dabei wird das Kohlendioxid vom Rauchgas getrennt und unter Druck verflüssigt. Auf diese Weise kann das CO dauerhaft in unterirdischen Gesteinsschichten gespeichert werden. Entsprechende Tests des Geoforschungszentrums Potsdam laufen dafür bereits im Untergrundgasspeicher bei Ketzin im Havelland. In der Pilotanlage soll die Technologie zur Marktreife gebracht werden.

Vattenfall rechnet etwa für das Jahr 2015 mit dem Bau einer größeren Demonstrationsanlage. Voraussichtlich ab 2020 soll das neue Verfahren in einem CO-freien 1000-MW-Braunkohlekraftwerk kommerziell genutzt werden. Vattenfall-Europe-Chef Klaus Rauscher spricht von einem „Projekt mit historischen Dimensionen“, weil mit der Technologie „irgendwann die gesamte Welt fossile Energieträger CO- frei einsetzen“ könne.

Verfahren kostet Energie

Die Greenpeace-Klimaexpertin Gabriela von Goerne hat die angepriesene Umweltfreundlichkeit der weltweit ersten Pilotanlage eines kohlendioxid-freien Braunkohlekraftwerks jedoch als Augenwischerei kritisiert. „Ich bezweifle, dass diese Technologie umweltfreundlicher sein wird“, sagte von Goerne. Zwar gebe es auf den ersten Blick einen Zugewinn für die Luftreinhaltung. „Man muss aber die gesamte Prozesskette anschauen, und da zeigt sich, dass das Absondern des CO sehr viel Energie kostet“, so von Goerne. In der Folge müsse mehr Kohle verbrannt werden. Zudem müssten die unterirdischen Speicher langfristig und aufwändig überwacht werden. Schließlich sei nicht klar, wie sich das Kohlendioxid auf Dauer im Untergrund verhalte. „Es ist ja nicht so, dass wir Kohlendioxid in den Untergrund bringen, Deckel drauf und das war's dann.“ (dpa, afp)

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Associated Press:From Biofuels to Wind, Quest for Energy Alternatives Steps Up
By Dave Carpenter

29.5.2006

CHICAGO — The future of energy is bright in Said Al-Hallaj's invention lab at the Illinois Institute of Technology, and not just because of the solar window that lies in development on a table.

All around the lab are advanced alternative energy projects that testify to the war on oil that's proceeding quietly at laboratories and research centers across the country.

A tiny two-passenger electric car stands ready to drive 25 miles on one charge of its custom-designed pack of lithium-ion batteries, not unlike the ones that power laptops. A research assistant who's working out the kinks on an electric bicycle motors down a hallway at 20 mph, triple the speed of the hybrid fuel-cell scooter developed here.

Elsewhere, Al-Hallaj and another professor are converting an SUV into a plug-in hybrid vehicle using lithium-ion cells to double the fuel efficiency and reduce emissions. And a team of students is converting a gasoline-powered lawnmower to use hydrogen as fuel.

Some of the projects could be manufactured commercially right now, said Al-Hallaj, research associate professor of chemical and environmental engineering and coordinator of IIT's renewable energy program. The problem is cost, which keeps them from competing with oil -- for now.

"The implications if we succeed are unbelievable," Al-Hallaj said. "You're coming up with a solution that is clean and advanced -- (good for) energy, the environment and people who are burdened by high prices."

Solutions for high gasoline prices might seem painfully far off to drivers as summer travel season begins, but experts say the skyrocketing costs of oil and gas have given new momentum to the push to develop alternative fuels and alternative energy sources.

The efforts are readily apparent in the nation's heartland, where a boom in ethanol is expanding and scientists at laboratories far and wide are working to turn agricultural waste or "biomass" such as switchgrass, wheat straw, cornstalks and miscanthus into a fuel called cellulosic ethanol that could be produced commercially to reduce U.S. dependence on oil.

In a separate burst of alternative energy developments unrelated to transportation fuels, wind farms are sprouting up across the country thanks to larger, more efficient turbines, and nascent coal-to-energy technology holds promise for pollution-free power plants in the future.

The driving force for most of the energy efforts, though, is oil. And researchers are thrilled about the impetus that soaring prices have given their work.

"With petroleum prices being as high as they are, the stars are aligning for looking seriously at alternative fuels and chemicals," said Hans Blaschek, a University of Illinois microbiology professor working on the conversion of corn into butanol, a promising alternative to petroleum-based fuels.

The highest-profile existing oil alternative is ethanol. The corn-based fuel might not hold the key to an oil-free future, but it is providing at least a stopgap remedy while scientists look beyond corn for an answer.

The runup in gas prices has softened for now the argument that ethanol isn't economically competitive without federal subsidies, and it has accelerated plans for ethanol plants by farmers' cooperatives and Archer Daniels Midland Co., the Decatur, Ill.-based agribusiness, among others.

Still, ethanol's potential is limited by cost and transport issues and the fact that even those seemingly endless fields of corn in the Midwest are finite. Experts say corn-based ethanol isn't ever likely to displace more than 10 percent of the gasoline supply.

"We just don't have enough corn," said Dan Basse, an analyst for Chicago-based AgResource Co. "If you turned every corn plant in the country into ethanol, there still wouldn't be enough."

That's where biomass comes in. By using other crops and forest waste along with the entire corn plant, not just the kernels, the Department of Energy says enough cellulosic ethanol could be produced by 2030 to lower U.S. gasoline consumption 30 percent.

Scientists at the National Center for Agricultural Utilization Research in Peoria are among those on a mission to expand ethanol beyond a grain-based fuel, working intensely on how best to break down the cellulose of biomass into sugars and complex chemicals in order to produce ethanol economically. An optimal solution might still be a decade away.

Mike Cotta, who heads the U.S. Department of Agriculture-run center in Peoria, says many technical challenges remain to be overcome. Researchers must come up with more inexpensive and environmentally viable ways of converting the polymers that the bulky biomass materials are made of into simple sugars.

But a lot has happened in recent years to move them closer to their goal, including great progress cited by Cotta in developing cheaper, more efficient enzymes to break the materials down.

"We're going to need some major breakthroughs, but once these things get in place ... it's going to happen," he said.

At Argonne National Laboratory, 25 miles southwest of Chicago, a variety of biomass-related projects are being carried out with close involvement of not only the Energy Department but large corporations such as ADM and energy group BP PLC. Teams immersed in biofuels research there for years have had their efforts not only validated but given new life by the intensified focus on high energy prices and by President Bush's call in this year's State of the Union Address for America to break its "addiction" to oil by developing alternative fuels.

"It's just been totally crazy," Seth Snyder, section leader for chemical and biological technology, said of the stepped-up demand for workshops and research information. "Everybody's interested now. ... We've been saying all along we can make a big impact, and suddenly people are saying 'Maybe these people are right.'"

Environmentalists and scientists alike applaud the fact that alternative fuels and alternative energy sources are in the spotlight more than ever, but they say energy efficiency is still being neglected.

"There are many people who believe that biomass has the power to replace our appetite for gasoline," said Kimberly Gray, professor of civil and environmental engineering at Northwestern University. "But that will only occur with significant improvements in energy efficiency and smart growth."

Without a trend toward more and smaller hybrid vehicles combined with high-density, walkable communities, Gray said, the suggestion by some experts that biofuels could virtually eliminate Americans' demand for gasoline by 2050 is unrealistic.

Another biofuel with promise is biodiesel, which uses vegetable oil and other nontoxic ingredients and can be blended with conventional diesel fuel. The trucking industry in particular has interest, and the Department of Agriculture says it can reduce carbon emissions by 78 percent.

But despite growing use in some areas of B11 -- an 11 percent biodiesel fuel -- overall consumption is still relatively tiny and biodiesel is not likely to be an everyday alternative for motorists in the near future. Only a handful of large biodiesel plants exist nationwide.

"It's a small interest, pretty much where ethanol was back in the '80s, but it's growing," Basse said.

Dayton Keyes of the central Illinois town of Maroa decided not to wait. Angry about prices spiraling ever higher, the 37-year-old police officer built a small biodiesel reactor in his garage last year and now tanks up his Volkswagen Golf with a homemade fuel concocted from used cooking oil.

"It just ticks me off to no end to see that even a 10-cent change in the average fuel price kills us and our politicians are doing nothing to solve it," said Keyes, who commutes 105 miles round-trip daily to his job in Springfield. "I thought, 'Shoot, I'm going to try to do something about this.'"

Inspired by media reports about a cross-country excursion using cooking oil as fuel, he found information on the Internet, ordered a how-to book and invested close to $1,000 in constructing a reactor -- plus a few hours every week brewing up batches of biodiesel.

The result is a fuel that costs him only about 70 cents a gallon, gets 45 miles per gallon and has converted him to a biodiesel proselyte who hopes to hasten the time when biofuels abound. He is trying to get a full-fledged biodiesel plant up and running.

"Renewable resources is a buzzword right now, but you don't see evidence of it," he said. "I'm trying to get a biodiesel revolution going where people will start making their own fuel."

Those now in labs trying to devise cheaper energy solutions applaud federal and state government support but emphasize that more will be needed if they are to succeed.

"A lot of people in government who ridiculed energy conservation and alternative energies ... are now investors," said Al-Hallaj. "The people who are funding these projects are the same ones who said, `Drill and spend and forget about it.'"

Rather than a single breakthrough, experts say it will likely take a combination of energy developments to help break free of oil's grip.

"There are a lot of people out there who think there's a silver bullet to answer the energy challenge facing this country -- one technology that will answer everything," said Gerald Groenewold, director of the Energy and Environmental Research Center in Grand Forks, N.D. "Some people say wind's the answer to electricity generation, ethanol's the answer to vehicle generation. We think it will be a mix of a lot of things."

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The Seattle Post-Intelligencer: Study: global warming boosts poison ivy

29.5.2006

WASHINGTON -- Another reason to worry about global warming: more and itchier poison ivy. The noxious vine grows faster and bigger as carbon dioxide levels in the atmosphere rise, researchers report Monday.

And a CO2-driven vine also produces more of its rash-causing chemical, urushiol, conclude experiments conducted in a forest at Duke University where scientists increased carbon-dioxide levels to those expected in 2050.

Carbon dioxide is a greenhouse gas - a chemical that traps heat similar to the way a greenhouse does - that's considered a major contributor to global warming. Greenhouse gases have been steadily increasing in the atmosphere since the Industrial Revolution.

Poison ivy is common in woods around the country, making it a bane of hikers, campers, fighters of forest fires, even backyard gardeners. Its itchy, sometimes blistering rash is one of the most widely reported ailments to poison-control centers, with more than 350,000 reported cases a year.

Compared to poison ivy grown in usual atmospheric conditions, those exposed to the extra-high carbon dioxide grew about three times larger - and produced more allergenic form of urushiol, scientists from Duke and Harvard University reported.

Their study appears in this week's Proceedings of the National Academy of Sciences.

"The fertilization effect of rising CO2 on poison ivy ... and the shift toward a more allergenic form of urushiol have important implications for the future health of both humans and forests," the study concludes.

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30.5.2006

La Semaine du développement durable commence le 29 mai pour se prolonger jusqu'au 4 juin Une manière d'inciter citoyens, collectivités et entreprises à changer leurs habitudes pour ménager la planète et le climat.

Le concept, issu du Sommet de la Terre à Rio en 1992, semble mieux connu du grand public: il s'agit de combiner croissance économique, progrès social et préservation de  l'environnement.

"En 2002, seuls 9 % des Français avaient connaissance de cette notion, aujourd'hui 50 % disent connaître le mot et 40 % peuvent en donner la définition. Le terme est bel et bien entré dans l'usage courant", estime la ministre de l'Ecologie, Nelly Ollin. "Le thème commence à prendre du sens", reconnaît Christian Brodhag, délégué interministériel au développement durable. Ce dernier s'avoue plus "dubitatif sur les changements de comportement" qu'occasionne cette semaine d'événements, organisée pour la quatrième année consécutive.

En l'occurrence, près de 1400 initiatives, soit le double de l'an dernier, ont été retenues.

Le MEDEF (patronat) occupe le terrain en lançant un guide d'une centaine de bonnes pratiques à destination des entreprises. Celles-ci sont de plus en plus nombreuses à communiquer sur le développement durable.

Le ministère de l'Environnement réfléchit aux possibilités d'étendre "l'étiquette énergie",  déjà appliquée aux voitures et à l'électro-ménager à d'autres produits. But: signaler leur valeur en dioxyde de carbone (CO2). Par exemple, comptabiliser et afficher les émissions de gaz à effet de serre sur une barquette de fraises importées du bout du monde hors-saison. D'ici là, "aux consommateurs de se montrer responsables", estime la ministre de l'Environnement.

Ethicity, une agence de conseil aux entreprises en matière de développement durable, a réalisé une enquête sur l'état d'esprit de l'opinion française sur le dossier, en interrogeant en mars 4500 personnes représentatives. Une sur deux "se sent concernée par l'état de la planète", explique Ethicity. 83 %  indiquent avoir pris conscience de leur pouvoir d'action au travers de leurs achats. Et plus de 20 % pensent qu'il faut simplement consommer moins". Si rien ne répond à ces préoccupations, prévient l'agence, "on court le risque de voir les plus gros consommateurs opter pour la décroissance".

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Environment News Service: China's Three Gorges Dam to Begin Flood Control With a Bang

29.5.2006

The moment of truth for the world's largest dam will arrive on June 6. The main concrete wall of the Three Gorges dam on the Yangtze River must begin to hold water after a temporary cofferdam is demolished in a series of planned explosions.

The last of three cofferdams used in building the massive dam, the 140 meter (460 feet) high and 580 meter (.3 mile) long cofferdam generated power for construction crews building the main dam's right bank and served as a temporary barrier, excluding water from an area of the main dam that will soon be submerged.

The final concrete was poured for the dam's main wall on May 20, so the cofferdam is no longer needed, and preparations for the June 6 blasting operation have been completed, said a source with the China Three Gorges Project Corporation.

About 200,000 cubic meters of concrete will be removed during demolition. Explosives have been placed 35 meters (115 feet) underwater, making the blast "extremely difficult," said the company.

The cofferdam removal means the main dam is expected to begin its flood control function in time for the 2006 flood season. China's main flood season usually lasts from June to August.

The dam is planned to protect 1.5 million hectares of farmland and towns in the Jianghan Plain and Dongting Lake area from flood damage. The region is inhabited by some 15 million people.

Officials with the China Three Gorges Project Corporation say the dam was engineered to prevent 10 year floods, control 100 year floods and "even in case of a rare occurrence of 1,000 year flood, mass damages or injuries can still be prevented."

Deadly floods are a frequent occurrance along the Yangtze, China's longest and the world's third longest river, after the Nile and the Amazon. Floods have claimed more than one million lives in the past 100 years. The latest flood in 1998 claimed about 1,000 lives and caused approximately 100 billion yuan (US$12.5 billion) in economic losses.

The Three Gorges - the Qutang, Wuxia and Xiling Gorges - extend for about 200 kilometers on the upper and middle reaches of the Yangtze River.

The 185 meter (607 foot) high and 2,309 meter (1.4 mile) long dam across the middle reach of the Three Gorges is the world's largest dam of reinforced concrete, with a total of 28 million cubic meters of concrete poured.

Located in the central province of Hubei, near the town of Sandouping, the massive dam is said to have cost US$25 billion over the 17 years it has been in planning and construction.

Designed for power generation as well as flood control, when operating at full capacity, now scheduled for 2008, the project's 26 hydropower turbines are expected to produce 18.2 million kilowatts, up to one-ninth of China's output.

Compared to the coal-fired power stations with equivalent generating capacity, the Three Gorges Power Plant will decrease emission of 100 million tons of the greenhouse gas carbon dioxide, according to the China Three Gorges Project Corporation. The emission of two million tons of sulfur dioxide and 0.37 million tons of nitrogen oxides, which both contribute to acid rain, will also be prevented, company officials said.

The project includes the largest system of locks ever built, engineered to bring cargo ships 1,500 miles inland to Chongqing, the capital of the municipality carved from Sichuan province in 1997 to govern the project.

Pu Haiqing, deputy director of the State Council Three Gorges Project Construction Committee, told the official state news agency Xinhua that the completion of the dam completes just one phase of the project, and a great deal of work remains, including resettlement and environmental protection.

Now that construction of the Three Gorges dam is almost completed, an independent and transparent financial and environmental audit is needed, says Probe International, a nongovernmental organization based in Toronto that has been a persistent critic of the dam.

"To sort economic fact from fiction, China needs a comprehensive independent audit of the real costs of the Three Gorges project," says Probe International Executive Director Patricia Adams.

The energy and environmental think tank has worked for two decades with Chinese environmentalists and scholars to monitor the Three Gorges project, and led the international campaign against Canadian financing for the multibillion-dollar scheme.

"The audit should document all the revenue raised and spent building the dam," Adams says. "The project's environmental consequences and the dam-related disaster risks must also be quantified and taken fully into account."

Claims by the government and dam authorities that the Three Gorges project will cost about 200 billion yuan (US$25 billion) have never been independently verified, says Adams.

"No one knows for sure how much money has been poured into the project since construction began over a decade ago, or what costs will be paid out of the dam's electricity revenues. Nor is it clear whether the official cost estimate includes an additional six turbines in an underground powerhouse that was not part of the original project design," she says.

The same financial uncertainty applies to the Three Gorges Corporation's profits, says Adams. She points out that The Three Gorges' listed subsidiary, Yangtze Power Company, reported profits of US$417.5 million last year but those profits have not been verified by China's new power-industry regulator, the State Electricity Regulatory Commission.

Once the dam's environmental costs and liabilities are factored into the price, Probe International estimates the true cost of Three Gorges power would be at least several times the government fixed price of US$0.03 per kilowatt-hour.

Adams says that any full audit of the Three Gorges project must review, "Corruption and abuses in the resettlement of more than one million people."

The audit must include "dangerous" buildup of silt in the Three Gorges Reservoir behind the dam that will flood 632 square kilometers (395 square miles) of land to create a reservoir about 644 kilometers (400 miles) long by 112 kilometers (70 miles) wide.

Adams is concerned about the impact of silt buildup on the entire project's performance and revenues.

Auditors should also consider the increased risk of earthquakes and landslides due to the presence of the reservoir, she says, as well as damage to fish stocks due to changes in river conditions and the blocking of fish migration routes.

The China Three Gorges Project Corporation says the dam will relieve the invasion of saline tide in the Yangtze River's estuary where it empties into the East China Sea near Shanghai.

Probe International says salt-water intrusion and land erosion problems in the Yangtze estuary will be increased, not relieved, by the upstream dam project.

Earlier this month, Chongqing Municipality's Kai County announced a tree planting drive to create greenbelts in the peripheral area of the reservoir, formed by the periodic variation of the shoreline. This "fluctuation" area is expected to cover 45.2 square kilometers (11,169 acres).

Last year, the county says it planted 2,533 hectares (6,260 acres) of forests around the reservoir.

For a diagram of the role of cofferdams in Three Gorges construction, visit: http://www.britishdams.org/about_dams/3gorges.htm

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Diario de Sevilla: Alertan de la pérdida de fondo marino en el mar Mediterráneo
madrid. Un estudio puesto en marcha por el Instituto Mediterráneo de Estudios Avanzados (Imedea) y la Fundación BBVA advierte de que la regresión de las praderas submarinas –ecosistemas que ocupan aproximadamente medio millón de kilómetros cuadrados a escala global, se sitúa entre un 1 y un 2 por ciento anual y que en el Mediterráneo esta cifra llega a alcanzar el 5 por ciento.

En esta investigación se ha comprobado que estas praderas submarinas tienen capacidad de secuestrar CO₂ –cerca de medio millón de toneladas al año en el mar Mediterráneo, lo que las convierte en los sumideros de CO₂ más importantes de todo el Mediterráneo–, de retener sedimento, filtrar partículas y alimentar playas con materiales. Así, la degradación conlleva la pérdida de la biodiversidad que estos ecosistemas mantienen ya que al dejar de secuestrar CO₂ se agravaría el problema de calentamiento global.

Los resultados de este proyecto científico han permitido verificar, asimismo, la vulnerabilidad de las praderas submarinas al aporte de materia orgánica procedente de granjas de acuicultura, emisarios submarinos o vertidos desde embarcaciones, entre otras fuentes.

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Marc Mennessier

30 mai 2006

La réglementation américaine fixant la séparation entre parcelles transgéniques et non-modifiées pourrait ne pas être adaptée à l'Europe. C'est le seul moyen d'éviter l'apparition d'insectes résistants.

COMMENT LIMITER l'apparition d'insectes résistants aux toxines produites par les maïs transgéniques Bt ? Autrement dit, comment éviter que cette méthode de lutte qui permet à la plante de contrer les attaques dévastatrices de la pyrale, un papillon parasite, en sécrétant dans ses tissus son propre insecticide, ne devienne progressivement inefficace ?

Alors que ces cultures controversées commencent timidement à se développer en France (5 000 à 6 000 hectares prévus cette année), des chercheurs de l'Institut national de la recherche agronomique (Inra) et d'un laboratoire du CNRS-université Toulouse 3 soulignent, dans une étude publiée aujourd'hui dans la revue PLoS Biology, que la stratégie dite des «zones refuges», telle qu'elle est pratiquée aux Etats-Unis, n'est pas infaillible. Et qu'il convient de l'affiner avant d'envisager son utilisation en Europe.

De quoi s'agit-il précisément ? A partir du moment où l'homme tente de limiter les effectifs d'une population d'être vivants (microbes, végétaux, insectes...) des mutations génétiques, survenues au hasard, peuvent rendre quelques individus insensibles aux poisons qui leur sont administrés. Et cela quels que soient les moyens employés : antibiotiques, pesticides ou, en l'occurrence, toxines sécrétées par un gène provenant de la bactérie Bacillus thuringensis (Bt) puis incorporé au maïs...

Brassage génétique

Du coup, ces individus, très minoritaires au départ, vont paradoxalement bénéficier d'un «avantage sélectif» par rapport à leurs congénères qui continuent de périr et qu'ils vont, de ce fait, peu à peu supplanter. Pour éviter de rendre l'ensemble de la population résistante, il faut soit réduire la nature ou la fréquence des traitements, soit assurer un minimum de brassage génétique – autrement dit de croisements – entre individus résistants et sensibles pour «diluer» au maximum la fréquence du gène mutant.

C''est ce qui est fait avec les zones refuges. En implantant des variétés de maïs classiques à proximité de champs de maïs transgénique, les insectes restés sensibles aux toxines Bt peuvent continuer à se reproduire et à maintenir leurs effectifs. Du coup, on diminue le risque de voir deux individus porteurs de la mutation s'accoupler, condition indispensable pour donner naissance à un papillon résistant.

Des travaux antérieurs ayant montré que les pyrales adultes sont capables de se disperser sur plusieurs centaines de mètres, les Etats-Unis ont imposé, il y a six ans, une distance maximum de séparation de 800 mètres entre les maïs Bt et les zones refuges. Mais elle pourrait s'avérer trop élevée.

Comme l'explique Denis Bourguet, chercheur à l'Inra et cosignataire de l'étude, «le brassage génétique n'est pas aussi important qu'on le pressentait au départ. Nos résultats prouvent que plus de la moitié des mâles et surtout des femelles pyrales, 57% exactement, s'accouplent sur leur parcelle d'origine avant de se disperser». En clair, ces individus ont plus de chances de convoler avec un partenaire de même type génétique qu'eux, sensible ou résistant, que s'ils migraient vers la parcelle voisine avant de donner libre cours à leurs ébats.

Pour autant, Denis Bourguet estime prématuré d'en tirer des conclusions sur l'efficacité du dispositif tel qu'il est pratiqué outre-Atlantique. La fréquence d'individus résistants reste en effet très faible (moins d'un sur un million), du niveau de celui de l'Europe, après dix ans de culture à grande échelle de maïs Bt. En 2005, 45% du maïs américain était transgénique. Mais il est impossible de savoir si ce résultat est à mettre à l'actif des zones-refuges ou si la proportion d'individus résistants reste à un niveau de toutes façons trop faible pour être détecté. En France, l'implantation de zones refuges est inutile car les cultures non transgéniques ultramajoritaires jouent naturellement ce rôle. Pour l'instant.

"We want to look at greenness as a concept," says Adrian White, analytic social psychologist at Leicester. "For example, is there one homogeneous type of green person? Do people who compost also drive hybrid cars, or are there those who drive to recycling bins in their SUVs?"

Underpinning the research is German psychoanalyst Erich Fromm's theory of trait biophilia. This contrasted two personality types and the behaviour each determined. White says: "At one end of the scale you have the biophile, who is attracted to life and has a productive, creative personality, [eg Gandhi]. At the other end you have the necrophile, who is antisocial and solitary [eg Hitler]. Most of us are somewhere between the two. We expect our study to show that biophilia is the best predictor of how well people treat the environment.

"Research over the past 30 years has shown that cruelty to animals is closely linked to cruelty to human beings," explains White. "This begs the question as to whether we have a disposition to life in all its forms. Does the way you treat the environment reflect the ways in which you treat other people?"

A recently completed pilot study involving 100 online respondents has produced interesting results. The first part of the questionnaire asked how environmentally active individuals were in relation to the advice to be found on the government's website. For instance: do you buy recycled goods? Do you fit low-energy light bulbs? Do you car share?

The second part detailed a general measure of environmentalism and asked questions such as: are you a member of an environmental group? Would you boycott the products of a company that pollutes? How likely would you be to campaign on behalf of the environment?

"Our interim findings have shown that women are significantly greener than men," White says. "A league table for UK regions has still to be completed, but the pilot does point to the East Midlands as being less green than the national average."

According to White, the behaviour of the over-45s is an indication that biophilia develops with age. "Young people do, of course, support the idea of improving the environment, and even join organisations such as Greenpeace," he says. "But this doesn't necessarily mean that they actually use bottlebanks. I think these early results bear this out."

White and his team are still analysing the demographic differences in terms of socio-economic and educational status. However, he admits that he would be surprised if they did not conform to Fromm's theory.

"I think it possible that those in caring professions are more likely to be environmentally friendly," he says. "And since the financial rewards in this sector aren't great, I think these people are less likely to be materialistic. It's a case of the importance of being, rather than of having, and is characteristic of trait biophilia. It informs that individual's overall orientation to life." He adds: "Individualistic cultures can be seen to wreak more environmental damage. They also have higher rates of offending than collectivist communities."

Data from the current survey of 2,000 people will be analysed and published by the end of the year. White plans to repeat the exercise annually, in order to establish what patterns emerge. "Breaking down how biophilia and green-friendly behaviour develop over a lifetime will provide us with invaluable information," he says. "And it is information we need if we are serious about wanting to protect the planet."

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