Plants display 'molecular amnesia': important discovery for genomics research and quest for better crops

Plant researchers from McGill University and the University of California, Berkeley, have announced a major breakthrough in a developmental process called epigenetics. They have demonstrated for the first time the reversal of what is called epigenetic silencing in plants. The study, "A Position Effect on the Heritability of Epigenetic Silencing," was published in the open acces journal PLoS Genetics. The discovery was made by researching maize plants.

The findings are important to develop a better understanding of gene regulation in the continuing quest to breed enhanced crops that produce higher yields, are more resistant to disease and can better tolerate environmental stress – all keys to helping improve the world's food, fiber, fodder and fuel supply. But perhaps even more important, the discovery may lead to new insights into how epigenetic processes work in the human body, which could assist in developing new ways of modifying our genetic makeup to help us avoid such diseases as cancer.

Although nearly every cell in our body is genetically identical, the researchers explained, each cell type expresses a distinct set of genes. Changes to the proteins around which DNA is wound are called "epigenetic" modifications, because they alter patterns of this gene expression without changing the actual DNA sequence. However, like changes in DNA sequence, epigenetic modifications can be passed on from parent cell to daughter cell, ensuring each cell line has the proper characteristics consistently over many generations.

This process must be repeated each generation, and there is good evidence in animals that, during early development, there is a wave of epigenetic reprogramming that effectively "resets" this system. Some genes, it seems, must be more actively reset than others. And genes that do the same thing in every cell, regardless of tissue type, may not have to be reset at all.

One kind of gene is quite distinct from all of the others, because it is nearly always epigenetically inactivated. These are the genes carried by transposons, or "jumping genes." Transposons are mutagens, genes that can modify their host cell in different ways, and lead to a predisposition to cancer, for example.

The researchers' experiments with maize suggest the propensity to maintain epigenetic states can vary depending on the position of the transposons within the genome.

Many organisms, from worms to humans to plants, have learned to tame transposons by epigentically "silencing" them: if they can't express their genes they can't jump. If they can't jump for long enough, their DNA sequence slowly accumulates errors, and they become molecular fossils. Most transposons in most organisms are silenced in this way, but some remain quite active.

In previous studies from the laboratory of two of the article's authors, UC Berkeley professors Damon Lisch and Michael Freeling, with the support of the National Science Foundation at UC Berkeley, epigenetic silencing was triggered in maize. Once triggered, the maize plant "remembers," and keeps the transposon "silenced" generation after generation, even after the trigger is lost:
energy :: sustainability :: biomass :: bioenergy :: plant biology :: molecular biology :: genetics :: epigenetics :: crop breeding :: maize ::

"However, we have found that at some positions in the genome, this is not the case. At these positions, although the trigger works fine, and the transposon is silenced, once the trigger is lost, the transposon reawakens," said Jaswinder Singh, a professor in the Plant Sciences Department at McGill University, and lead author of the new article.

This "molecular amnesia" has never before been documented in plants and no one has seen it associated with a particular position in the genome of any species before. These data suggest the epigenetic landscape of plant genomes may be more subtle and interesting than previously thought, with the ability to remember epigenetic silencing varying depending on position.

"This may relate to the degree to which a given gene or group of genes must be reprogrammed each generation," Singh said. "We can now use transposons to probe for variations in the epigenetic landscape of the maize genome. It may turn out that forgetting can be as important as remembering. Our findings suggest that erasure of heritable information may be an important component of epigenetic machinery."

References:
Singh J, Freeling M, Lisch D (2008) "A Position Effect on the Heritability of Epigenetic Silencing", PLoS Genet 4(10): e1000216. doi:10.1371/journal.pgen.1000216

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Young people prefer cars over green transport options

Some worrying news: young people find the prospect of driving cars more attractive than other modes of travel that are kinder to the environment, according to research conducted by a researcher at the University of the West of England. The results indicate there is a lot of work to do on making public transportation and even cycling 'sexier'.

Dr Tilly Line has just completed her PhD entitled ‘The attitudes of young people towards transport in the context of climate change.’ Dr Line’s work examined how young people are influenced by knowledge about climate change when it comes to making choices about how they will travel when they become adults. The study concentrated on the views of young people aged between 11 and 18 years and the findings found an overwhelming desire by young people to drive.

Specific attention was give to how climate change considerations affect these intentions. Overall it was found that the participants have a general understanding of the link between transport and climate change, but when it comes to their attitudes towards different modes, they place higher value on identity, self-image, and social recognition than the environment. It is this that explains their positive attitudes towards the car and driving in favour of alternative modes. For example, the participants pointed to learning to drive as “a mile-stone in teenage life” - something that everyone does at seventeen. They also pointed to the car as a symbol of social status and the importance of their role as a driver in their friendship groups. - Dr Line

Some comments from young people who took part in the study:

Limousines, they’re like a really special thing for like if you’re posh or you have lots of money. That’s why I want to have one of them. - 11 yr-old female participant

Me and my friends share lifts to school in the mornings. Now our friends, all of our group have actually passed, we take it in turns to drive places...we share everything. - 18 yr-old female participant

Dr Line adds that, although it is recognised that transport policy makers are likely to require an understanding of the degree to which these values and attitudes are universally held among young people, it is suggested that policy aimed at reducing the public’s reliance on the car and increasing their use of alternative modes, should recognise such values, particularly in relation to soft policy measures (including marketing activities) targeting the socio-psychological motivations for travel choice.

For example, one answer may be to promote cycling as a signal of success and ‘being cool’, rather than promoting the environmental benefits of this behaviour.

The importance of climate change shouldn’t be forgotten however. It isn’t the case that young people dismiss this issue, but more that they feel powerless to make a difference. Dr Line found that the young people think of climate change as being something that will not be felt until far off in the future and that there is little that they can do as individuals:
energy :: sustainability :: biomass :: bioenergy :: petroleum :: transportation :: public transport :: bicycle :: car culture :: climate change ::

There are little things you can do, but nothing that will change the world, because individually we’re only little people. - 11 yr-old female participant

I’d like to change it. But I know I wouldn’t be able to, just me. If I really tried I know that I would just be wasting my life trying to do one thing I knew I couldn’t change. - 11 yr-old female participant

The participants also suggested that although they receive information about what climate change is, they lack information about what they can do to tackle it:

You don’t really get told what to do. …Instead of just saying ‘we’re polluting the world’, tell us what we can do about it. - 11 yr-old male participant

Dr Line concludes: "On a positive note, I found that a number of the young people welcomed the idea that hard policy ideas leading to enforced travel behaviour away from reliance on cars would lead to a change in behaviour. But that this would only be possible if walking, cycling and public transport was easily accessible and reliable. This was even the case amongst those participants already driving and it seemed to stem from the belief that such action would empower more people to attempt to tackle climate change through changes in their travel behaviour as everyone would have to behave in the same way."

I think some people may want to help the environment but they don’t do anything about it but then again if they were forced to then they’d have to. ...I mean eventually it’s going to happen anyway. It’s going to come to a point in time where there’s going to be a ban on cars or something …there’s just going to be no feasible way they can have all the cars on the road. - 18 yr-old male participant

References:
Bristol UWE: Young people choose cars above greener transport options - December 04, 2008.

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Cover crops and composting can offset carbon loss from corn stover ethanol production

As the United States continues to develop alternative energy methods and push towards energy independence, cellulosic-based ethanol has emerged as one of the most commercially viable technologies. Corn stover remains the most popular source available, but the loss of soil organic carbon (SOC) associated with the removal of corn fodder as a cellulosic ethanol feedstock is of agricultural and environmental concern. In a recently published article, researchers found that it may be wiser to replace corn with energy crops like miscanthus and switchgrass, because they not only yield more biomass, they also build carbon in soils, instead of removing it (previous post).

However, in the November-December 2008 issue of Agronomy Journal, scientists from Michigan State University show that with 'carbon augmentation' practises, even corn fields can become carbon sinks. They report on the effectiveness of the integration of cover crops, manure, and compost, to supplant carbon loss in corn stover removed by cropping systems. The results indicate that corn stover based bioenergy cropping systems can be managed to increase short-term carbon sequestration rates and reduce overall net global warming potential by using no-till planting methods and a manure-based nutrient management system [note: no mention of biochar yet - which may be a vastly superior carbon augmentation practise, because it doesn't merely sequester carbon temporarily, it does so quasi-permanently; in some types of soil, biochar also improves some of the most important soil functions, thus reducing fertilizer needs and lowering emissions of potent greenhouse gases like N2O and CH4].

The MSU research team measured soil carbon changes as well as nitrous oxide and methane gas emissions from corn stover-ethanol field plots managed under various carbon augmentation practices (table, click to enlarge). In addition to the gas emissions measured in the field, other carbon emissions assessed included estimates for the manufacturing carbon cost of crop inputs; methane emissions from the livestock manure source; methane and nitrous oxides generated during manure storage and application; and the fuel used in crop production and in gathering and land applying the manure.

“These results show that bioenergy cropping systems, particularly those integrating livestock manure into their management scheme, are a win-win option on both alternative energy and environmental fronts,” says Kurt Thelen, member of the research team.

Thelen says this research demonstrates that under proper management, livestock manure can supplant carbon lost from corn stover removal, and actually provide an environmental benefit, both in terms of greenhouse gas (GHG) mitigation, and from the established improved soil properties associated with increasing SOC levels such as increased water retention:
energy :: sustainability :: biomass :: bioenergy :: biofuels :: ethanol :: corn :: cellulosic :: soil carbon :: no-till :: cover crops :: manure :: biochar ::

For every gallon of gasoline burned, the equivalent of 19 lbs of CO2 is released to the atmosphere which contributes to the environmental GHG problem, says Thelen. Conversely, this work shows that in the not too distant future, choosing a cellulosic ethanol alternative at the pump may actually result in a net removal of CO2 from the atmosphere.

Research is ongoing at Michigan State University to evaluate the environmental, agronomic, and economic sustainability of bioenergy cropping systems. Support for this work was provided by USDA-CSREES, the CASMGS program, and the Michigan Agricultural Experiment Station.

Picture: Harvesting corn leaves and stems for use in biofuel production reduces carbon in the soil, the researchers found. The more material harvested, the less carbon in the soil. Credit: Photo by Don Hamerman.


References:
Bradley E. Fronning, Kurt D. Thelen and Doo-Hong Min, "Use of Manure, Compost, and Cover Crops to Supplant Crop Residue Carbon in Corn Stover Removed Cropping Systems", Agronomy Journal, 100:1703-1710 (2008), DOI: 10.2134/agronj2008.0052

Biopact: Perennial biomass crops build soil carbon - December 04, 2008

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Perennial biomass crops build soil carbon

Converting farm fields to energy crops can increase or decrease greenhouse gas emissions, depending on where – and which – biofuel crops are used, University of Illinois researchers report this month. The researchers analyzed data from dozens of studies to determine how planting new biomass crops can influence the carbon content of the soil. Their findings will appear next month in the first issue of the journal Global Change Biology Bioenergy - a new scientific journal in the Global Change Biology series, published by Blackwell.

Plants use the sun's energy to convert carbon dioxide from the atmosphere into the organic carbon that makes up leaves, stems and other plant parts. As plants decay, this carbon goes into the soil. Organic carbon is an important component of soil health and also influences atmospheric carbon dioxide levels. Whenever the soil is disturbed, as occurs when land is plowed or cleared of vegetation, some of this carbon returns to the atmosphere in the form of carbon dioxide.

From the time that John Deere invented the steel plow, which made it possible to break the prairie sod and begin farming this part of the world, the application of row crop agriculture to the Midwest has caused a reduction of soil carbon of about 50 percent, says Evan DeLucia, a professor of plant biology at Illinois and corresponding author on the new study.

Any debate on the environmental consequences of using plants to produce liquid fuels should also consider how each option affects soil carbon, DeLucia said.

The biggest terrestrial pool of carbon is in the soil. The top meter of soil holds more than three times the amount of carbon stored in either vegetation or the atmosphere, so if you do little things to change the amount of carbon in the soil it has a huge impact on the atmosphere and thus global warming. - Evan DeLucia

Unlike corn, which must be replanted every year, perennial grasses such as switchgrass and Miscanthus preserve and increase carbon stores in the soil. These and other grasses have been proposed as high-energy alternative feedstocks for biofuel production:
energy :: sustainability :: ethanol :: biomass :: bioenergy :: biofuels :: energy crops :: perennial :: polyculture :: switchgrass :: miscanthus :: soil carbon ::

Currently, ethanol is produced by fermenting the starch in corn kernels, but significantly more liquid fuel energy can be harvested from the stems and leaves of plants. The technology for producing this "cellulosic" ethanol is still quite expensive, but many believe that it will displace corn ethanol as the technology advances.

About 20 percent of the corn crop currently goes into ethanol production in the U.S., DeLucia said, "so we began with the hypothesis that it might be good for soil carbon to put a perennial biofuel crop on the landscape instead of corn."

The researchers analyzed published estimates of changes in soil organic carbon in landscapes converted from natural or agricultural land to biofuel crops. They focused on corn, sugar cane, Miscanthus, switchgrass and native prairie grasses. They also evaluated the impact of harvesting and using corn stover (the plant debris left over after corn is harvested) as a cellulosic biofuel source.

Their analysis showed that converting native land (grassland or forest) to sugarcane dramatically reduced soil carbon, creating a carbon deficit that would take decades to repay. While perennial grasses add carbon to the soil each year, DeLucia said, it could take up to a century for the sugar cane to rebuild soil carbon to former levels on native land.

Harvesting the corn residue for cellulosic ethanol production also reduced the carbon in the soil. The more plant residue was removed, the more the soil carbon declined.

Planting perennial grasses on existing agricultural lands had the most beneficial effect on soil carbon, the researchers found. Although there was an initial drop in carbon as fields were converted from corn to Miscanthus, switchgrass or native perennial grasses, the loss was fairly quickly offset by yearly gains in soil carbon as the grasses became established.

"Consistent with our hypothesis, the perennial feedstocks like Miscanthus and switchgrass start building soil carbon very, very early on," DeLucia said. "From a purely carbon perspective, our research indicates that putting perennial biofuel crops on landscapes that are dominated by annual row crops will have a positive effect on soil carbon."

The finding "seems to walk you right into the food for fuel debate," DeLucia said, referring to the controversy over using agricultural land for fuel production. But because the U.S. is already devoting about 20 percent of its corn crop to ethanol production, he said, it would make sense to eventually use that land to produce a much higher yielding biofuel feedstock that has the added benefit of increasing organic carbon in the soil.

DeLucia and his colleagues will present their findings this month at the 2008 Fall Meeting of the American Geophysical Union. Evan DeLucia is also an affiliate of the Institute for Genomic Biology and the Energy Biosciences Institute at the University of Illinois.

Quicknote on biochar
It's interesting to note that DeLucia has not yet looked at biochar, a new technology that turns the equation on its head. With biochar, crops are grown to turn them into a stable form of carbon that can be permanently sequestered in soils (or biomass waste is used). This sequestration via biochar is quasi-permanent - the carbon stays locked up for hundreds to thousands of years.

This is in contrast with the carbon sequestered either by no-till farming or by perennial grass crops as the one studied by DeLucia. These forms of carbon sequestration are only temporary. In the no-till case, the biomass in the soil is turned into CO2 and other GHG gases very rapidly. After a few years, all the carbon has been released back into the atmosphere. Biochar, on the contrary, locks up the C for centuries.

Biochar is made by pyrolysing biomass. Interestingly, during this pyrolysis process - heating in the absence of air or in a low oxygen environment - hydrogen-rich 'waste' gases can be captured and used to produce energy. If used to replace fossil fuels, this bio-energy is no longer carbon-neutral, but effectively carbon-negative because of the total amount of C used as a feedstock, around 50% is sequestered into soils.

One of the most interesting research pathways into bioenergy farming systems, will be the study of growing carbon-sequestering polycultures of perennial crops, and using them in biochar concepts.

Liquid or solid biofuels?
Another point to note is that turning cellulose into biofuels is not the most efficient way to use a given stream of biomass. A considerable number of studies shows that on a farm-to-wheel basis, using biomass for the generation of electricity used in (plugin-) electric vehicles is much more efficient than converting that biomass into a liquid or gaseous fuel for use in internal combustion engines. A still more efficient way to use biomass is in combined heat and power (CHP) or for pure heat generation.

A recent Canadian study, for example, showed that using solid biofuels generate heat presents a five to 10-fold increase in the capacity to offset greenhouse gas emissions, compared to first-generation biofuels (earlier post). Cellulosic ethanol would be more efficient than first-generation fuels, but they remain liquid energy sources - that is, the cellulose undergoes an energy-intensive conversion process - to be used in the rather inefficient internal combustion engines.

The future of biomass for transportation may well be the production of energy crops for biochar, the waste-energy of which is used to generate carbon-negative electricity for use in electric vehicles (driving such a car would mean that you would not simply be generating "zero emissions", you would actually generate "negative emissions" and take CO2 out of the atmosphere -- see "the strange world of carbon-negative energy"). Such integrated biomass energy and char concepts, would be coupled to smart-grids and to the other renewables that are going to power the electric transportation future.

Picture: Converting agricultural land to perennial grasses, such as Miscanthus, has a beneficial effect on soil carbon. Credit: Photo by Don Hamerman

References:
Global Change Biology Bioenergy - Article not yet available at the time of publishing.

Energy Biosciences Institute.

Biopact: Study: solid biofuels 570% more efficient than corn ethanol in reducing GHG emissions - September 10, 2008

More on perennials as bioenergy crops:
Biopact: Tallgrass Prairie Center to study polyculture prairie hay for bio-electricity: combining conservation and restoration with bioenergy - December 03, 2007

Biopact: Carbon negative biofuels: from monocultures to polycultures - December 08, 2006

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CGIAR: Targeted agricultural investments will yield high results, slash poverty in Africa

The Consultative Group on International Agricultural Research (CGIAR), the world's leading agricultural research group, is calling for specific investments in African agriculture to make hundreds of millions of people there less vulnerable to volatile world markets, economic crises and climate change. Investing in Africa's agriculture and focused crop research offers tremendous returns, the group says. The current crises offer an excellent opportunity to make socially relevant investments that could help the poor in a way that no other investment can.

Concerned that the global financial crisis will lead to cuts in funding for projects in developing countries, leaders of the CGIAR told a conference that relatively modest, well-targeted investments could greatly boost the livelihoods of people living on less than $1 a day.

Speaking at the group's annual meeting in Maputo, the experts on global agriculture warned that cuts in funding for research or programs for implementing new discoveries would be catastrophic for millions of smallholder farmers and their families throughout Africa and much of Latin America and Asia.

Our researchers have proven in the past that just small amounts of funding can boost crop yields, defeat devastating pests, and ultimately lift farmers and their families out of poverty – allowing them to earn enough money to send their children to school. - Katherine Sierra, CGIAR chair

Substantially increasing public investment in agricultural research in the developing world as well as investment in the CGIAR over the next five years would by 2020 cut by more than half the number of people in sub-Saharan Africa living on less than $1 a day, according to a new report by the International Food Policy Research Institute (IFPRI). It is one of the 15 research centers supported by the CGIAR.

The report concluded that the expansion of long-term agricultural research and development will be critical to ensure food security for the poor, especially in light of the major ramifications of a global economic slowdown, on top of the adverse impacts of climate change on crop yields.

With both the financial and food crises already starting to affect us now – and with climate change impacts on the horizon – it is especially important to make well-targeted investments that bolster agricultural output across the world. - Ren Wang, CGIAR's director

In the last year, a report by a number of African agricultural experts at the Association for Strengthening Agricultural Research in Eastern and Central Africa (ASARECA), the CGIAR, and Regional Strategic Analysis and Knowledge Support Systems (ReSAKSS), found that global food price inflation often has no relation to the price in developing countries – and sometimes the increase in local price is far above the global average. One reason for the volatility is that developing countries are insufficiently integrated into regional markets.

"Best Bets" for Investments in Agriculture
The IFPRI report gives more than a dozen specific financial forecasts on the returns from increased investment in agricultural research, showing how the return can be multiplied many times. The CGIAR's "best bets'' for future research priorities include:

• Controlling severe stem-rust infections in wheat, which has spread from eastern Africa to the Middle East and beyond. This would require US$37.5 million and benefit nearly half the world's population – 2.88 billion people.
• Boosting small-scale fisheries, which would help improve the livelihoods of 32 million fishing families in Africa and Asia, and improve the diets of millions more. This would call for US$73.5 million.
• Finding and developing drought-tolerant maize varieties and spreading them in Africa, which would cost US$150 million and directly benefit 320 million Africans.

biomass :: bioenergy :: biofuels :: energy :: sustainability :: agriculture :: food :: research :: rural development :: poverty alleviation :: Africa ::

For many years, agricultural research has received neither the attention nor the investment it requires to help farmers on a large scale, said Joachim von Braun, director general of IFPRI, who spoke at Monday's opening of the CGIAR meeting.

We have a great opportunity today. We've already proven that our research has impact, generating huge benefits for poor farmers and consumers. We now need to scale up this success.

Farmers Benefit from Research Results
The efforts of CGIAR scientists have already helped millions of people, for example, the spread of New Rice for Africa varieties – or NERICA. Average upland rice yield has long stood at 1 ton per hectare in sub-Saharan Africa. But farmers report now that NERICA varieties are yielding two to five times more than that.

In southern Nigeria, Janet Olatunji, along with other members of a farmer cooperative in the village of Ogbese, was skeptical at first about NERICA varieties, which were developed by CGIAR scientists. But in 2007, her one hectare of rice earned a profit of $1,200 – a windfall for her. This year, she planted three hectares of the NERICA varieties.

In Mozambique, another success is in the making through the promotion of new varieties of sweetpotatoes. These have two major benefits – offering farmers a productive cash earner and providing their children with additional vitamin A which is extremely important for their development.

"I'm starting to feed sweetpotato to my baby,'' said Deolinda Charles, 32, who carried her four-month-old baby, Carlos, on her back inside a wrap one day earlier this year in the village of Boane, about 20 kilometers outside Maputo's city center. "The researchers told me that it would help him grow up well, that he would get vitamin A from it. That makes me very happy.''

Global Overview of Crises: Financial Systems to Food Prices
The CGIAR's annual meeting highlighted those and other successes. But several of the world's leading thinkers on global agriculture voiced serious concerns. Mozambique's president, Armando Guebuza, opened the conference with a speech about opportunities to invest in Africa's agricultural markets – stressing that donors and investors must not miss this opportunity to have a major impact.

At an afternoon plenary session, four experts focused on new demands on agricultural research and promising areas in which research can help produce much greater crop yields. The speakers included von Braun, the IFPRI director general; Hans Herren, the 1995 World Food Prize Laureate and co-chair of the International Assessment of Agricultural Knowledge, Science, and Technology for Development; A. Namanga Ngongi, president of the Alliance for a Green Revolution in Africa (AGRA); and Justin Lin, Sr., vice president and chief economist of the World Bank.

Lin spoke about how global economic trends could impact agriculture in the developing world. Von Braun also addressed that issue, citing specific examples of how investment in agriculture could make a significant difference in the lives of poor farmers.

The CGIAR is a strategic agricultural research alliance dedicated to generating and applying the best available knowledge to stimulate agricultural growth, raise farmers' incomes, and protect the environment. It supports 15 research centres worldwide conducting groundbreaking work to nourish the future.

References:
CGIAR: Annual General Meeting 2008 - Investing in Agricultural Science: The Best Bet for the Future - Maputo, Mozambique : December 1- 5, 2008

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Fraunhofer researchers make bioplastic from liquid wood

Bioplastics made from cellulosic biomass, such as forestry or crop waste, offer a smarter way to use biomass than turning it into liquid biofuels. Per hectare of crops grown or per quantity of biomass, cellulosic bioplastics offset more petroleum and GHG emissions than liquid cellulosic biofuels (previous post). Most of these next-generation bioplastics, which no longer rely on easily extractible starch or sugar like that found in corn or sugarcane, are made from a limited range of feedstocks and research is still in an early stage. However, German engineers from the Fraunhofer Institute have already added a new feedstock for bioplastics and show the final product is ready for market. The plastics are made from what's called 'liquid wood', a lignin-rich product.

Most plastics are based on petroleum. A bioplastic that consists of one hundred percent renewable raw materials helps to conserve this resource. Limiting its use also reduces greenhouse gas emissions. The researchers have optimized the new wood-based plastic in such a way that it is even suitable for products such as Nativity figurines. Toys have to put up with a lot of rough treatment: they are sucked by small children, bitten with milk teeth, dragged along behind bobby cars, and every now and then they have to survive a rainy night outdoors. Whatever happens, it is vital that the material does not release any softeners or heavy metals that could endanger children.

Toys can be made of the new feedstock, called 'liquid wood', in the future. The advantage is that this bioplastic, known as 'Arboform', is made of one hundred percent renewable raw materials, more specifically lignin-rich biomass, and is therefore neither depenent on fossil oil or easily extractible starches, vegetable oils or sugar from crops.

Researchers at the Fraunhofer Institute for Chemical Technology ICT in Pfinztal and the Fraunhofer spin-off TECNARO GmbH have developed the material. But what exactly is liquid wood?

The cellulose industry separates wood into its three main components – lignin, cellulose and hemicellulose, explains ICT team leader Emilia Regina Inone-Kauffmann. The lignin is not used in papermaking, however. Researchers at TECNARO mix lignin with fine natural fibers made of wood, hemp or flax and natural additives such as wax. From this, they produce plastic granulate that can be melted and injection-molded.

Car parts and urns made of this bioplastic already exist, but it is not suitable for toys in this form: To separate the lignin from the cell fibers, the workers in the cellulose industry add sulfurous substances. However, children’s toys should not contain sulfur because, for one reason, it can smell very unpleasant.

Now the scientists were able to reduce the sulfur content in Arboform by about 90 percent, and produced Nativity figurines in cooperation with Schleich GmbH. Other products are in the planning stage, says TECNARO’s managing director Helmut Nägele.

This is a challenging task: sulfur-free lignins are usually soluble in water – and therefore unsuitable for toys. On no account must they dissolve if they are left out in the rain or if children suck them. With the aid of suitable additives, the TECNARO scientists were able to modify the bioplastic in such a way that it survives contact with water and saliva undamaged.
A big question is: can the material be recycled?
energy :: sustainability :: biomass :: bioenergy :: wood :: lignin :: bioplastic :: renewable :: recycling ::

To find that out, the researchers produced components, broke them up into small pieces, and re-processed the broken pieces – ten times in all. They did not detect any change in the material properties of the low-sulfur bioplastic, so that means it can be recycled, says Inone-Kauffmann.

It will be interesting to study the energy and carbon balance of products made by this new process. If they were to show a strongly positive balance, they could become a green resource capable of reducing a considerable amount of petroleum. Lignin is considered to be, worldwide, the largest but most under-utilized biomass feedstock available for bioenergy and bioproducts.

The question is whether the liquid wood bioplastics will be able to compete with potentially more lucrative lignin-based products, such as carbon fiber composites, which are currently under study.

Image: Nativity figurines made of 'liquid wood' called Arboform. Credit: TECNARO GmbH and Fraunhofer-Gesellschaft

References:
Biopact: Researchers find bio-based bulk chemicals could save up to 1 billion tonnes of CO2 - December 17, 2007

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CarboAfrica project: Africa can reduce atmospheric CO2 levels, agriculture to play crucial role

Although Africa contributes significantly to global greenhouse gas (GHG) emissions from sources other than fossil fuels, it could be absorbing more carbon from the atmosphere than it puts back in, according to CarboAfrica, an international research project of 15 institutions from Africa and Europe that includes the UN's Food & Agriculture Organisatin (FAO). To get the most out of Africa's future climate role, reducing emissions from agriculture is considered to be crucial. So is preserving the continent's existing carbon sinks.

Studying wild fires in South Africa's Kruger Park, carbon dioxide flows in the rainforest of Ghana or weather patterns in Sudan, CarboAfrica's research indicates that, as opposed to its minor part in global GHG emissions from fossil fuels — less than 4% of the world's total — Africa makes a major contribution to GHG emissions from natural sources, FAO said today.

As to deforestation and fires, Africa accounts for 17 percent and 40 percent of the global aggregate emissions respectively. In addition, it strongly influences the atmospheric variations of CO2 between seasons, and from year to year — half of them can be attributed to Africa.

"These first results show that Africa plays a key role in the global climate system," said Riccardo Valentini of the University of Tuscia, Italy, and project coordinator of CarboAfrica, which was set up in 2006 with €2,8 million of funding from the European Commission's research department.

It's the carbon cycle
What matters most though, Valentini stresses, is the balance between carbon captured through photosynthesis by Africa's vast expanse of forests and savannas, and carbon released into the atmosphere as a result of deforestation, fires and forest degradation — Africa's ‘carbon cycle'.

Our evidence so far indicates that Africa seems a ‘carbon sink', meaning that it takes more carbon out of the atmosphere then it releases. If confirmed, this implies that Africa contributes to reducing the greenhouse effect, thus helping mitigate the consequences of climate change. - Riccardo Valentini, CarboAfrica project leader

CarboAfrica has been observing Africa's Sub-Saharan carbon cycle through a network of monitoring stations in eleven countries for the last two years.

The preliminary results, to be finalized by 2010, were discussed at a conference in Accra/Ghana, that brought together over 100 participants from the international scientific community, governments and the United Nations.

Agriculture is crucial
"Agriculture must play a central role in reducing Africa's carbon emissions even more," said Maria Helena Semedo, Representative of FAO's Regional Office for Africa, opening the meeting:
energy :: sustainability :: biomass :: bioenergy :: carbon cycle :: greenhouse gas emissions :: agriculture :: carbon sink :: deforestation :: Africa ::

"We should reach out to farmers in Africa, teaching them how to use their land and their forests in such a way that Africa's carbon cycle becomes our ally in the battle against climate change," she said. "It is crucial, and possible, that such efforts contribute to increasing food security at the same time."

Ms Semedo stressed that through appropriate soil management, such as practiced by conservation agriculture, GHG emissions from agriculture can be reduced, while at the same time increasing productivity and even harnessing agriculture against the woes of climate change.

In line with the UN's Convention on Climate Change, avoiding deforestation and extending Africa's forest cover, should be another top priority.

References:
CarboAfrica website.

CarboAfrica introductory leaflet [*.pdf]

FAO: climate change portal.

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Biochar could help tropical forest conservation

The conservation of tropical rainforests and other biodiverse ecosystems in the (sub)tropics faces tremendous challenges. Simply declaring that a region becomes a conservation area without taking away the pressures that threaten the integrity of the area, doesn't work. The social and economic needs of local populations have to be taken into account. And this is where many conservation projects often fail. Biochar, a technique to boost the fertility of poor tropical soils, could help in solving this particular problem.

Conservation challenges
Forest conservation projects are confronted with pressures that range from the global (e.g. the expansion of agriculture in response to global market forces) to the very local (e.g. slash-and-burn farming by poor rural people who rely on this technique to survive.) The global forces are difficult to control, but the local pressures can be addressed. Most conservation projects will attempt to search for alternative livelihoods for the local people who used to depend on the ecosystem that is now to be protected. But this in itself is a major challenge. Not all people who live in and around a conservation area can be employed in ecotourism, for example. And these populations still need food, energy and social services to meet their basic needs, so the pressures on the conservation zone will remain.

When a conservation project turns local farmers into forest guards or tourism guides, the farming activities may be phased out in the immediate vicinity of the area, only to pop up elsewhere because local demand for food, fiber, forest products and energy does not disappear. This phenomenon, known as 'leakage' is one of the weak points of most current forest conservation efforts. In some cases, projects may even generate 'conservation refugees' - people who are chased away from their land that is turned into a protected area, and now need to fend for themselves elsewhere. In extreme cases this violence can involve the use of military force (see the brilliant overview in the forthcoming book by Mark Dowie, Conservation Refugees - The Hundred-Year Conflict between Global Conservation and Native Peoples, MIT Press, May 2009).

However, nowadays most conservation efforts are 'hybrids', in that they no longer militarize conservation areas, but instead open them up so that local people can keep benefiting from their land and forests. However, this requires complex and expensive transitions from rudimentary land use techniques - such as slash-and-burn farming - to more refined concepts, such as agroforestry.

The emergence of a growing market for ecosystem services may greatly help forest conservation projects, because this market would generate extra revenues that can tackle some of the challenges. The funds may flow towards the people who would else have been displaced by the project or whose livelihoods need to be transformed to make it work.

Biochar: a win-win-win
This is where biochar, a promising new land-use strategy, comes in. Biochar can simultaneously protect conservation areas, without the need to force local farmers to give up farming, while tapping ecosystem service markets and preventing 'leakage'. Biochar might thus represent a win-win-win situation and make forest conservation projects more feasible:
energy :: sustainability :: biomass :: bioenergy :: land-use :: biochar :: rural development :: tropical forests :: conservation ::

How is this possible? It is easy to understand. Biochar is a carbon-rich product obtained from the pyrolysis of biomass. When this porous, recalcitrant substance is added to acidic, nutrient-poor tropical soils -- the infertile soils that push people in tropical forest areas to rely on slash-and-burn farming -- the soils become far more fertile and productive. Biochar does this by positively altering the fundamental biological, chemical and physical properties of these problem soils. Among other things, biochar makes soils less acidic, enhances their nutrient and water retention capacity, increases their cation exchange capacity, and aerates the soil.

Biochar can thus short-circuit the slash-and-burn cycle, make subsistence farming at the forest frontier far more productive, and thus reduce local pressures on forests. More food, fiber and biomass can be produced on a plot of land that has been amended with char. In some cases, grain yield increases of 880% have been recorded when highly weathered soils received biochar and mineral fertilizer, as compared to the same soils only receiving fertilizer. Depending on local circumstances, a single hectare of farm land amended with biochar can protect some 5 to 20 hectares of pristine forest.

What is more, biochar not only enhances the productivity of poor tropical soils and thus reduces pressures on local ecosystems, it also doubles as a stable, permanent carbon sink. That is: it helps fight climate change. In the future there should be carbon credits available for sequestering biochar in soils. Biochar projects could thus generate two types of carbon credits: direct credits obtained from storing recalcitrant char in soil, and indirect credits obtained from avoiding deforestation.

Linking biochar and forest conservation
When biochar projects are linked to conservation areas, a potential synergy emerges that can overcome the gap between the economic needs of local rural populations and the requirement to reduce pressures on the protected zone.

By creating 'biochar buffers' around forest areas, local farmers could keep on farming and supply local populations with food, fiber, fodder and forest products. Because their fields are now far more productive, their farming activities would not threaten the conservation area. Farmers would remain farmers. Conservationists would not have to transform the local people's lives by inventing entirely new jobs for them. At the same time, the risk of 'leakage' is reduced as well: food and biomass production will not be displaced, but remains locally rooted.

Moreover, biochar's capacity to restore the fertility of depleted soils makes it possible to expand these 'biochar buffers' outwards, away from the conservation area. Without biochar, local farmers would work their way inwards, toward the protected region as their soils deplete and they need new land. They would thus threaten the integrity of the conservation zone. With biochar, abandoned farm plots with their depleted soils that no longer yield food, can be taken back into production.

One of the key pressures on forest conservation zones, namely land clearing for farming, would thus be deflected and even turned around. As biochar zones expand outward and keep generating enough food and biomass on previously abandoned land, the margins around the conservation area can gradually be reforested.

The concept of creating 'biochar buffers' around conservation areas needs to be explored further. The way we presented it here is crude and many questions about the feasibility of such a concept remain. But the growing evidence of biochar's capacity to keep soils productive, especially at the tropical forest frontier, hints at a potential synergy between conservation and local development.

References:
Christoph Steiner: Slash-and-char as Alternative to Slash-and-burn - soil charcoal amendments maintain soil fertility and establish a carbon sink, Cuvillier Verlag, December 2007.

Mongabay: "Ancient Amazonian technology could save the world" - May 17, 2007

Mongabay: The biochar revolution begins - Biochar fund to fight hunger, energy poverty, deforestation, and global warming - March 10, 2008

On conservation projects that generate 'conservation refugees', see the work of an NGO that grew out of resistance to the creation of a natural park in the Omo valley of Ethopia: Native solutions to conservation refugees.

Mark Dowie, Conservation Refugees - The Hundred-Year Conflict between Global Conservation and Native Peoples, MIT Press, May 2009.

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