Scientists: GM crops can play role in sustainable agriculture

Genetically modified (GM) crops may contribute to increased productivity in sustainable agriculture, according to a major study published in the June 8 issue of the journal Science. The research analyzes, for the first time, environmental impact data from field experiments all over the world, involving corn and cotton plants with a Bt gene inserted for its insecticidal properties.

The analysis [*abstract] was conducted by scientists at the National Center for Ecological Analysis and Synthesis (NCEAS) at the University of California, Santa Barbara, The Nature Conservancy, and Santa Clara University. The study is accompanied by a searchable global database for agricultural and environmental scientists studying the effects of genetically engineered crops ("Nontarget Effects of Bt Crops" database).

Biotechnology and genetic engineering are controversial because of concerns about risks to human health and biodiversity, but few analyses exist that reveal the actual effects genetically modified plants have on other non-modified species. In an analysis of 42 field experiments, scientists found that this particular modification, which causes the plant to produce an insecticide internally, can have an environmental benefit because large-scale insecticide spraying can be avoided. Organisms such as ladybird beetles, earthworms, and bees in locales with “Bt crops” fared better in field trials than those within locales treated with chemical insecticides.

“This is a groundbreaking study and the first of its kind to evaluate the current science surrounding genetically modified crops. The results are significant for how we think about technology and the future of sustainable agriculture.” - Peter Kareiva, chief scientist of The Nature Conservancy

According to lead author, Michele Marvier, of Santa Clara University, says the research for the first time provides an answer the question: do Bt crops have effects on beneficial insects and worms? The answer is that it depends to a large degree upon the type of comparison one makes. When Bt crops are compared to crops sprayed with insecticides, the Bt crops come out looking quite good. But when Bt crops are compared to crops without insecticides, there are reductions of certain animal groups that warrant further investigation. What is clear is that the advantages or disadvantages of GM crops depend on the specific goals and vision for agroecosystems:
biofuels :: energy :: ethanol :: biomass :: bioenergy :: energy crops :: agriculture :: biotechnology :: GM crops :: insecticides :: sustainability ::

As NCEAS Director, Jim Reichman explains, “This important study by an interdisciplinary research team reveals how an in-depth analysis of large quantities of existing data from many individual experiments can provide a greater understanding of a complex issue. The project is enhanced by the creation of a public database, Nontarget Effects of Bt Crops, developed by NCEAS ecoinformatics expert, Jim Regetz, that will allow other scientists to conduct congruent analyses.”

But GM crops are not only controversial for environmental reasons. Scientists have found that so-called 'terminator seeds' have had devastating social effects in some developing countries. These GM seeds make poor farmers dependent on multinationals, from which they have to buy new seeds every season. Traditionally, farmers use their knowledge and the seeds from their harvested crops to grow new plants the next season. But with the introduction of GM seeds both this knowledge and self-sustenance gets lost, as it was recently outlined in an interesting anthropological study of farmers in Warangal, India (earlier post).

So even though the new public database on "Nontarget Effects of Bt Crops" will be very useful in studying the environmental effects of GM crops across the world, a similar database of socio-economic effects on local communities would be welcome too.

The debate on GM crops is becoming increasingly important in the context of bioenergy and biofuels. In some countries, GM crops are already being used on a large scale for the production of ethanol (corn, maize) and biodiesel (canola, rapeseed), and serious research efforts are underway to develop next-generation genetically engineered energy crops that can be engineered in such a way that their properties allow for more efficient bioconversion. Major genome sequencing initiatives for biomass crops have been launched in the EU and the US, with the poplar - a potential energy crop - being the first tree to have had its entire genome revealed. Likewise, the cassava genome is being sequenced with the aim of improving starch production.


More information:
Michelle Marvier, Chanel McCreedy, James Regetz, Peter Kareiva, "A Meta-Analysis of Effects of Bt Cotton and Maize on Nontarget Invertebrates", Science, 8 June 2007:
Vol. 316. no. 5830, pp. 1475 - 1477, DOI: 10.1126/science.1139208

National Center for Ecological Analysis and Synthesis: New Study Finds Genetically Engineered Crops Could Play a Role in Sustainable Agriculture [*.pdf] - June 7, 2007.

Biopact: Plant scientists develop new tool to protect crops from modified genes - February 26, 2007

Biopact: Anthropological study explores the effects of genetically modified crops on developing countries - January 27, 2007

Biopact: The first tree genome is published: Poplar holds promise as renewable bioenergy resource - September 14, 2006

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China considers discontinuing coal-to-liquids projects

A recent study from the Carnegie Mellon Electricity Industry Center (CEIC) in the U.S. concludes that while enacting policies to subsidize the production of coal-to-liquids (CTL) transportation fuel would enhance national security by lowering oil imports, encouraging plug-in hybrids powered by coal-generated electricity is a less costly policy that also reduces oil imports and does more to lower greenhouse gas (GHG) emissions.

China, which is rich in coal but poor in petroleum and gas, has been on the forefront of experimenting with CTL fuels, but may put an early end to these projects, an official with the country's top economic planning agency has said (precisely because of some the reasons summed up in the CEIC's and similar studies).

The consideration came at a seminar hosted by Chinese Academy of Engineering, which looked at alternative fuels, in particular biofuels, and their role in the country's long-term energy security. Denmark-based Novozymes, the world's leader in enzymes and microorganisms used for the production of biofuels, was present.

After an evaluation of the nation's limited energy resources and its environmental status, a deputy director of the industry department of the National Development and Reform Commission (NDRC) told the seminar held in Beijing that "liquefied coal projects consume a lot of energy, though the successful industrialization of liquefied coal could help reduce the country's dependence on petroleum."

The liquefaction of coal is not only energy intensive but also results in a large amount of GHGs. The CEIC full life-cycle analysis of gasoline obtained from coal shows that the fuel results in complete 'well-to-wheel' emissions of 360 pounds CO2 equivalent per MMBtu of gasoline in the worst-case scenario and 220 pounds CO2 equivalent per MMBtu of gasoline in the best-case scenario (converted into annual CTL gasoline emissions: 1.18 lbs/mile (536.7 g/mi) in the worst case; 0.72 lbs/mile (325 g/mi) in the best case). This compares negativey with the well-to-wheel emissions of 264.6 g/mile for the conventional coal-generated electricity used in plug-in hybrids; 105.8 g/mile for the scenario with plug-in hybrids using electricity from advanced Integrated Gasification Combined Cycle (IGCC) plants with carbon capture and storage (CCS). The baseline for conventional gasoline was 344 g/mile (graph, click to enlarge).

In short, converting coal into liquid fuels is not a particularly sensitive thing for a country that is set to become the world's largest emittor of GHG's. The Chinese government said earlier it would invest more in developing alternative energy resources including biomass fuel and liquefied coal to substitute petroleum during the 11th Five-Year Program (2006-2010) period, amid concerns over the country's growing dependence on petroleum. But criticism in China over CTL-plans has been growing steadily (here):
energy :: sustainability :: ethanol :: biodiesel :: renewable :: biomass :: bioenergy :: biofuels :: greenhouse gas emissions :: coal :: coal-to-liquids :: China ::

China, the world's second-largest energy consumer, imported 162.87 million tons of oil in 2006, driving the country's reliance on imported oil up 4.1 percentage points from a year earlier to reach 47 percent, official statistics show.

The country is also confronted with huge capital demand and higher consumption of water and coal in producing the liquefied coal, the official said. A project in north China's Inner Mongolia Autonomous Region with a designed capacity of 1.08 million tons would need more than 50 billion yuan (US$6.58 billion) of investment, according to the NDRC's deputy director for industry.

He said the country had begun the coal-liquefying projects without trial industrialization operation, and the technologies involved were not sophisticated yet. And both coal and petroleum are non-renewable energy resources, he added. However, the country has never slackened its efforts to find substitutes for petroleum.

China said last week it had successfully excavated methane hydrates (also known as natural gas ice) from below the floor of the South China Sea after nine years of research in this field. Recovering these gas hydrates remains risky and requires much more research before being commercialised on any scale.

Meanwhile, China wants to meet its growing energy needs while reducing fossil fuel consumption as much as possible. The Chinese government therefor recently announced, in its first climate plan, it upheld the development of renewable resources as an important national strategy, and would continue to boost the development of biomass fuels and biogas, hydro-power, solar and wind power.

An ambitious biofuel project announced earlier this year consists of the establishment of a biomass forest the size of England (13 million hectares) in the province of Yunnan from which the China National Petroleum Corp (CNPC) will extract an estimated three-quarters of a million barrels per day of liquid biofuels.

Multinationals like South-Africa's Sasol, a pioneer in coal-to-liquids technolgy, has partnered with Chinese companies on a CTL project in the country, as has Royal Dutch Shell.

More information:
Xinhua: China may halt production of liquefied coal - June 10, 2007.

Paulina Jaramillo and Constantine Samaras, "For energy security and greenhouse gas reductions, plugin hybrids a more sensible pathway than coal-to-liquids gasoline", Carnegie Mellon Electricity Industry Center, April 2007.

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