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    Mongabay, a leading resource for news and perspectives on environmental and conservation issues related to the tropics, has launched Tropical Conservation Science - a new, open access academic e-journal. It will cover a wide variety of scientific and social studies on tropical ecosystems, their biodiversity and the threats posed to them. Tropical Conservation Science - March 8, 2008.

    At the 148th Meeting of the OPEC Conference, the oil exporting cartel decided to leave its production level unchanged, sending crude prices spiralling to new records (above $104). OPEC "observed that the market is well-supplied, with current commercial oil stocks standing above their five-year average. The Conference further noted, with concern, that the current price environment does not reflect market fundamentals, as crude oil prices are being strongly influenced by the weakness in the US dollar, rising inflation and significant flow of funds into the commodities market." OPEC - March 5, 2008.

    Kyushu University (Japan) is establishing what it says will be the world’s first graduate program in hydrogen energy technologies. The new master’s program for hydrogen engineering is to be offered at the university’s new Ito campus in Fukuoka Prefecture. Lectures will cover such topics as hydrogen energy and developing the fuel cells needed to convert hydrogen into heat or electricity. Of all the renewable pathways to produce hydrogen, bio-hydrogen based on the gasification of biomass is by far both the most efficient, cost-effective and cleanest. Fuel Cell Works - March 3, 2008.


    An entrepreneur in Ivory Coast has developed a project to establish a network of Miscanthus giganteus farms aimed at producing biomass for use in power generation. In a first phase, the goal is to grow the crop on 200 hectares, after which expansion will start. The project is in an advanced stage, but the entrepreneur still seeks partners and investors. The plantation is to be located in an agro-ecological zone qualified as highly suitable for the grass species. Contact us - March 3, 2008.

    A 7.1MW biomass power plant to be built on the Haiwaiian island of Kaua‘i has received approval from the local Planning Commission. The plant, owned and operated by Green Energy Hawaii, will use albizia trees, a hardy species that grows in poor soil on rainfall alone. The renewable power plant will meet 10 percent of the island's energy needs. Kauai World - February 27, 2008.


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Saturday, September 06, 2008

The problem with wind power in the UK: increased dependence on fossil fuels

The BBC News science section has an interesting sketch of the different ways in which Europe's wind power potential and costs are tied to different regional circumstances. Simon Cox asks what happens when the wind doesn't blow, and compares the reality of intermittent power production in Denmark and the UK. In Britain, it is concluded, scaling up wind power will either mean an increased dependence on ever costlier fossil fuels - a troubling outcome - or heavy extra costs for energy storage or for exports.

Experts counter this conclusion by stating that the baseload for wind in the UK does not have to be dirty or costly, but can come from biomass instead of fossil fuels (previous post on the UK's Renewables Advisory Board, which is increasingly seeing biomass power plants as key elements of an overarching strategy on reliable renewable energy).

In Denmark, Europe's most successful wind energy nation, excess power is exported to neighboring countries via an integrated infrastructure. And when the wind doesn't blow, the country buys electricity from the same neighbors to make up the balance. In the UK, however, this option is out of the question: there is a link to France and one being planned to Holland but these won't be able to shift the amount of power needed to balance the system when based on large scale wind power. Building the necessary infrastructure would make wind a very costly renewable energy source.

Another idea for Britain would be to store its wind power in giant batteries, but this is difficult, untried and again, very expensive.

This leaves backing up wind with fossil fueled baseloads. Most feasible will be a reliance on gas-fired power stations as these are the easiest to turn off and on. But this will mean a "dash for gas" - a resource that Russia, hardly Britain's most cooperative ally, has in spades.

Dieter Helm, professor of energy policy at Oxford University, says Britain could find itself badly exposed when it bets on wind power that needs to be backed up by ever more expensive and unreliable gas supplies. It would be "about the worst possible thing that one could conceive of given what's going on in Russia and given our dependence on Russian gas supplies":
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It could also prove costly. The energy company E.On recently estimated back-up power could cost up to £10bn per year across all the energy suppliers. That would add £400 to the average annual household energy bill for all Britons. Wind energy would not be the low-cost energy resource many predicted it to be.

The British government accepts it is a challenge to manage energy security and price rises but it is fully committed to reaching the EU's 2020 target. And to do this, it has taken wind power into the energy mix. But the questions surrounding the ambitious plans are mounting. If wind power mean an increased reliance on ever costlier fossil fuels, the 'renewable' and 'clean' resource may not be so green as expected. And the argument that wind power would boost energy security, would no longer hold, the experts say.

The EU is expecting its renewables target to become legally binding within the next year so the UK could be hauled before the European courts of justice and face huge fines, if it doesn't comply. This pressure has opened the door for alternatives to intermittent wind power. More and more policy makers, as well as renewable energy companies are looking at biomass, which is being increasingly seen as the more attractive renewable energy source - and precisely the one that can make wind really green by providing a clean baseload.

References:
BBC: When the wind doesn't blow - September 5, 2008.

Biopact: RAB: biomass now the key renewable energy source, as backlash against wind and solar grows - July 29, 2008.

Biopact: Energy major Total will not invest in wind power - the base-load fallacy -
October 15, 2007



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Friday, September 05, 2008

Pyrenees' glaciers may disappear in less than 50 years

Much has been said about the situation of the glaciers in Greenland and Antarctica, but little is known about those in the high mountain areas of the Iberian Peninsula. A Spanish study has now revealed, for the first time, that of all mountain areas only the Pyrenees has active glaciers left. What is more, the steady increase in temperature - a total of 0.9°C since 1890 - indicates that Pyrenean glaciers will disappear before 2050, according to the experts.

Researchers from the University of Cantabria, the Autonomous University of Madrid and Valladolid have produced a summary on the current situation in the Pyrenees, the Sierra Nevada and the Picos de Europa. The scientists based their work on how climate change has affected the glaciers since the so-called Little Ice Age (from 1300 to 1860) to conclude that only the Pyrenees have active glaciers left.
High mountains are particularly sensitive areas to climate and environmental changes, and how glaciers evolve there in response to climate change is one of the most effective indicators of current global warming, in this case evidenced in Iberian mountain ranges - Juan José González Trueba, lead researcher and professor from the University of Cantabria
The work, recently published in the journal The Holocene, represents Spain’s scientific contribution to the question of climate change effects on high mountains and glaciers. The authors compiled extensive data from current and historic glacier studies, as well as information from Spain’s ERHIN Programme to sketch the evolution of the deglaciation process to date. Their findings are a clear warning signal.

60% of Pyrenean glaciers have melted

There are currently only 21 glaciers in the Pyrenees (ten on the Spanish side and eleven on the French side) covering an area of 450 hectares. In just 15 years, since 1990, glaciological calculations have shown that rapid melting has caused the total regression of the smallest glaciers and 50%-60% of the surface area of the largest glaciers.

According to the study, between 1880 and 1980, at least 94 glaciers disappeared in the Iberian Peninsular altogether, and since the 1980s, the remaining 17 glaciers have disappeared as well. Glaciers are sensitive geoindicators of climate change. They are also features with a high heritage value. And most importantly, they provide drinking water to a large part of the planet's population.

A look back at the past
The glaciers in the Iberian Peninsula's mountains were formed in the Little Ice Age. The coldest period in which the greatest spread of glaciers in the Spanish high mountains was recorded occurred between 1645 and 1710:
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Between 1750 and the beginning of the 19th century small glaciers receded in the Pyrenees but soon recovered thanks to a new period of low temperatures. However, since then, temperatures have risen between 0.7ºC y 0.9ºC in Spain’s northern mountains, showing the effects of global warming.

The first evidence of the existence of glaciers in the Picos de Europa was discovered in the notes of geographers, naturalists and travellers at the end of the 19th century. Recent studies have shown that Cantabrian glaciers existed in historic times, always located on the north faces of the highest peaks, under an oceanic climate at extremely low altitudes, from 2190m to 2600m.

In the Sierra Nevada, scientists have verified the existence of the southernmost glacier in Europe during the Little Ice Age, under Mediterranean climate conditions, and where factors promoting the accumulation of snow were altitude, orientation (north side) and topographic conditions. This glacier, also indicated by the first naturalists, disappeared at the beginning of the 20th century. The rise in temperature caused its melting until it was transformed into a small “ice lens” buried beneath a dense blanket of deposits.

Image: glacier of the Monte Perdido in the Pyrenees. Credit: SINC / Juan José González Trueba.

References:

González Trueba, J.J; Martín Moreno, R.; Martínez de Pison, E.; Serrano, E. “’Little Ice Age' glaciation and current glaciers in the Iberian Peninsula”. The Holocene 18(4): 551-568 June 2008.

SINC: Los glaciares de los Pirineos desaparecerán en menos de 50 años - September 4, 2008.


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New framework to account for effect of aerosols on precipitation

A group of scientists affiliated with the International Geosphere-Biosphere Programme (IGBP) have proposed a new framework to account more accurately for the effects of aerosols on precipitation in climate models. Their work appears in the 5 September issue of Science magazine. Understanding the effects of aerosols on precipitation is of key importance to better assess the risks of flooding, drought and the availability of water for agriculture.

The increase in atmospheric concentrations of man-made aerosols — tiny particles suspended in the air — from such sources as transportation, industry, agriculture, and urban land use not only poses serious problems to human health, but also has an effect on weather and climate.

Recent studies suggest that increased aerosol loading may have changed the energy balance in the atmosphere and at the Earth’s surface, and altered the global water cycle in ways that make the climate system more prone to precipitation extremes.

It appears that aerosol effects on clouds can induce large changes in precipitation patterns, which in turn may change not only regional water resources, but also may change the regional and global circulation systems that constitute the Earth’s climate.

The proposed framework improves scientists’ ability to simulate present and future climates by integrating, for the first time, the radiative and microphysical effects of aerosols on clouds. The radiative effects of aerosols on clouds mostly act to suppress precipitation, because they decrease the amount of solar radiation that reaches the land surface, and therefore cause less heat to be available for evaporating water and energizing convective rain clouds. Microphysical effects of aerosols can slow down the conversion of cloud drops into raindrops, which shuts off precipitation from very shallow and short-lived clouds.

Model simulations suggest that this delay of early rain causes greater amounts of cloud water and rain intensities later in the life cycle of the cloud. This suggests that rain patterns are shifting, leading to possible drought in one area and flooding downwind in another area. In addition, greater cooling below and heating above leads to enhanced upward heat transport. Model simulations have shown that greater heating in the troposphere enhances the atmospheric circulation system, shifting weather patterns due to changes in convective activity.

Investigations of aerosol/precipitation effects are especially relevant to policy issues, as effects on the hydrological cycle may affect water availability, a great concern in many regions of the world:
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The IPCC, in its latest climate change assessment report, declared aerosols to be "the dominant uncertainty in radiative forcing (a concept used for quantitative comparisons of the strength of different human and natural agents in causing climate change)”. Therefore, aerosols, clouds and their interaction with climate are still the most uncertain areas of climate change and require multidisciplinary coordinated research efforts.

To that end, authors of the Science article are participating in a new, international research project designed to study the connections between aerosols, clouds, precipitation and climate (ACPC project). The project will bring together an international multidisciplinary group of scientists from the areas of aerosol physics and chemistry, cloud dynamics, and cloud microphysics under theauspices of two international research programmes, the International Geosphere-BiosphereProgramme (IGBP) and the World Climate Research Programme (WCRP).

Picture: aerosol contamination over Northern India and Bangladesh. Credit: Wikimedia Commons.

References:
Daniel Rosenfeld, Ulrike Lohmann, Graciela B. Raga, Colin D. O'Dowd, Markku Kulmala, Sandro Fuzzi, Anni Reissell, Meinrat O. Andreae, "Flood or Drought: How Do Aerosols Affect Precipitation?", Science 5 September 2008: Vol. 321. no. 5894, pp. 1309 - 1313, DOI: 10.1126/science.1160606


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Thursday, September 04, 2008

Huge growth of biomass sector in the UK


The United Kingdom is one of the worst performers in the EU when it comes to increasing its share of renewables in the energy mix. However, the country is rapidly speeding up its investments in clean energy, with biomass spanning the crown.

The UK now has a dedicated biomass capacity larger than 1400MW operational and in the pipeline. The interest in biomass has grown strongly because of its inherent advantages over intermittent sources and its cost-effectiveness.

Farmers Weekly Interactive has an interesting overview of recent developments in the sector in the UK.

Biomass fuels in Britain are both produced locally as well as imported. Many of the large power plants are located in coastal areas, facilitating (long distance) imports. Fuels include both waste biomass (wood from industry, green waste) as well as fuels made from dedicated energy crops, such as miscanthus or short rotation willow. Imports include wood chips and pellets from Scandinavia and Canada.

Besides large power plants, the number of smaller, dedicated co-generation plants that yield both power and heat in a highly efficient manner is on the rise.

Picture: dedicated energy crops, like Miscanthus x giganteus, are increasingly used as a fuel for power generation in the UK. Credit: Farmers Weekly Interactive.
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Research: site-specific nitrogen applications can increase profitability when fertilizer prices are high

With recent increases in grain and fertilizer prices, even small changes in management may significantly impact profit, as researchers report in Agronomy Journal. Varying the rate of crop production inputs such as fertilizer and seed makes intuitive sense, as farmers have long observed differences in crop yield in various areas of a single field. The availability of spatial yield information from combines equipped with yield monitors has provided a good resource for improved management.

So, optimizing inputs to match yield potential of different areas within fields may increase profit and reduce the environmental impact associated with over-application of fertilizer or pesticides. With recent substantial increases in grain and fertilizer prices, even small changes in management may have the potential to significantly impact profit from a field.

Scientists with the University of Nebraska-Lincoln (UNL) compared an approach to site-specific nitrogen and seed density management for irrigated maize, based on soil properties and yield potential zones, to whole field uniform management based on current University of Nebraska best management practices (BMPs).

The researchers wanted to know if the site-specific approach could increase yield or nitrogen-use efficiency (the amount of grain produced per kilogram of nitrogen applied), and the effect of site-specific management on profitability. The study was conducted on two irrigated maize fields in Nebraska in 2003 and 2004 -- a total of four site-years.

Four treatments were then compared each year in field length strips, evaluating uniform management of nitrogen and seed density (current BMP), variable nitrogen rate plus uniform seed density, uniform nitrogen rate plus variable seed density, or both variable nitrogen rate and seed density. The variable nitrogen rate was based on yield potential within each zone, spatial patterns of soil organic matter within each zone, and zone-average residual soil nitrate-nitrogen values, using the University of Nebraska recommendation algorithm for maize.

Yield levels in both years generally followed the order of historical yield zones, though at Site 1 in 2003 average grain yields were not different among yield zones. Uniform nitrogen and seed density management resulted in high yields for all four site years, and site-specific management strategies resulted in no or small yield increases. Only at Site 1 in 2003 were there small but statistically significant yield increases with variable rate nitrogen management. There were no significant effects of seed density on yield, nor any interactions between seed density and nitrogen rate.

Fertilizer nitrogen use efficiency (NUE) was high in all site-years and well above national averages. NUE was particularly influenced by the amount of residual nitrate-nitrogen present in the soil profile prior to planting. At Site 1, NUE tended to be highest with the strategy that combined variable rate nitrogen with uniform seed density. At Site 2 in 2003, there was no advantage to variable rate nitrogen in NUE, while in 2004 a variable rate strategy which applied more nitrogen in high-yielding areas of the field resulted in the highest NUE:
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At Site 1 in 2003, variable rate nitrogen management increased the gross economic return above fertilizer costs. However, for the other three site-years, there were no significant effects of site-specific management on profitability.

The conclusion of the study was that, using the strategies the researchers selected, they could not demonstrate consistent significant economic benefits to site-specific management. One site-year did indicate an economic benefit to site-specific management, but this was before costs associated with collecting and analyzing site-specific information were included. However, this economic analysis was conducted using 2004 values of grain and fertilizer.

With significant increases in the price of fertilizer and the value of grain in 2007 and 2008, the value of using site-specific management is likely to have increased for those locations where site-specific management has a significant impact on yield, NUE, or both.

The researchers believe variable rate nitrogen application will be most profitable in situations with relatively wide maize to nitrogen fertilizer price ratios, and where a significant yield increase over uniform management is likely. They found little benefit to variable seed density, likely due to plasticity in yield components in response to different plant populations. Site-specific adjustment of seed density in irrigated environments is probably best applied to areas of known low yield potential in order to reduce seed cost.

References:

J. L. Pinga, R. B. Fergusonb, and A. Dobermannc, "Site-Specific Nitrogen and Plant Density Management in Irrigated Maize", Agronomy Journal, 100:1193-1204 (2008), DOI: 10.2134/agronj2007.0174

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Wednesday, September 03, 2008

World's largest biomass plant running on chicken manure online in the Netherlands


Today, Gerda Verburg, Dutch Minister of Agriculture, Environment and Food Quality, opened the world's largest biomass power plant running exclusively on chicken manure. The €150 million project is owned and operated by multi-utility company Delta, cooperative DET, ZLTO and Austrian Energy & Environment A.G. (a consortium including Siemens Nederland N.V.) The facility will deliver renewable electricity to 90,000 households. The biomass power plant solves a key environmental problem in the Netherlands: managing the vast excess stream of chicken manure, which, until today, had to be processed at a high cost.

The biomass power plant will utilize approximately 440,000 tons of chicken manure, roughly one third of the total amount produced each year in the Netherlands. Many European countries, including the Netherlands, suffer under an excess of different types of animal manure that pollute the environment. Costly methods are used to avoid it being spread out over land, to process it or to avoid creating the excess in the first place. Using the manure as a carbon-neutral energy source has become the most efficient, environmentally-friendly, and cost-effective of all management options.

Interestingly, the biomass power plant is more than merely "carbon neutral". If the chicken manure were to be spread out over farm land, it would release not only CO2, but also methane, a very potent greenhouse gas. By using the manure for power generation, the release of methane is avoided.

The biomass power plant - unique because it exclusively burns chicken manure - has a capacity of 36.5MW, and will generate more than 270 million kWh of electricity per year. The facility is located on the Moerdijk in Zeeland, and will serve approximately 90,000 households.
Generating renewable and sustainable energy requires innovation. Innovating is costly and time-consuming, but important to make the transition from fossil to renewable fuels. The biomass power plant is one of the strategic components of our energy mix, which includes a wide range of renewable sources, as well as nuclear power. This diverse energy mix is needed to meet the ever increasing demand for electricity, but for us, building a smart and clean fuel sourcing strategy is more than meeting the consumer's demand, it is a matter of meeting our social obligations. - Peter Boerma, CEO Delta
The cooperative "Duurzame Energieproductie Pluimveehouderij (DEP)" (Sustainable Energy Production in the Poultry Sector) brings the chicken manure to the power plant. DEP has a member base of 629 poultry farmers, 70% of them operating in the south of the country. The power plant offers the poultry farmers an environmentally friendly, structurally sound and commercially interesting option enabling them to manage their production of chicken manure.

The Netherlands produces approximately 1.2 million tons of chicken manure per year. Until now, 800,000 tons of this amount was processed abroad, at high costs. One third of this amount will now be used in the biomass power plant. The ashes from the combustion of the manure are rich in phosphorus and kalium, and will be sold as a fertilizer with a high added value:
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The most obvious question many people in Moerdijk raised is whether the large amounts of chicken manure, when transported to and processed in the power plant, would leave a stench. The engineers who built the facility took care to address this issue: all the manure is transported in airtight trucks and is only released for processing once the trucks have entered an air lock in the fuel processing area.

The power plant's construction began on august 28, 2006 and cost €150 million. The facility provides jobs to 25 people. The project is the result of a cooperation between Delta, the cooperative DEP, Zuidelijke Land- en Tuinbouworganisatie (ZLTO) and Austrian Energy & Environment A.G.

These partners, alongside regional and national government in the Netherlands, are now looking into building similar biomass power plants to deal with other excess streams of manure.

References:
Delta: Van mest naar stroom - September 3, 2008.

Omroep Brabant: Verburg opent biomassacentrale Moerdijk [video and podcasts] - September 3, 2008.



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Australia: new positive biochar results, concept on political agenda


According to the New South Wales Department of Primary Industries (NSW DPI), scientists have found more positive results which reinforce the potential of ‘biochar’ to revolutionise climate mitigation and adaptation in Australian agriculture. Researchers found a 150% increase in maize yield when poor soils were amended by biochar. Because of these and other major benefits, biochar has reached the political agenda, with Minister for Primary Industries Ian Macdonald saying that it is a possible saviour for Australia’s carbon-depleted soils, and has multiple greenhouse gas benefits. A first project to assess the feasibility of building a renewable energy power plant that simultaneously yields electricity with negative emissions and biochar has been initiated.

Researchers from the NSW Department of Primary Industries (NSW DPI) continue to unlock the potential of biochar, which is a charcoal-like product that is the residue of a renewable energy production process called slow-pyrolysis. Products like paper mill waste, green waste, animal manures or other biomass can be recycled by heating to 550 degrees Celsius in the absence of oxygen, generating energy and biochar.

Adding biochar to soil not only provides an economical way to sequester carbon, but also has soil health benefits which will help farmers adapt to climate variability and increase productivity. Minister Macdonald said a number of scientific projects within NSW DPI were researching biochar, testing its value as a soil amendment and developing it as a tool for climate change mitigation.
Biochar holds particular potential for long-term carbon sequestration, improving soil health and water holding capacity, and further reducing emissions of greenhouse gases associated with fertiliser application. Recent studies have found a 150 per cent increase in corn yield when biochar is applied at the rate of 20 tonnes to the hectare. - Ian MacDonald, Minister of Primary Industries
NSW DPI scientists are working on placing an economic valuation on biochar to promote commercial production and application of the product. They are undertaking a scoping study for a slow-pyrolysis plant on the north coast of NSW. The study is in collaboration with BEST Energies Australia, Ballina Council and the Department of State and Regional Development.

The study is a feasibility assessment for building a facility in the Northern Rivers region as a commercial demonstration and will include a preliminary economic analysis. If adopted within NSW, slow-pyrolysis plants could take biomass waste from urban and rural areas converting it into valuable products (energy and biochar) for use in agriculture and forestry:
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Minister Macdonald also recognised the contribution of DPI scientists Lukas Van Zwieten, Stephen Kimber, Annette Cowie, Yin Chan and BP Singh who contributed to the book, Biochar for Environmental Management. The book will be launched at an international conference next month.

The scientists

The NSW DPI scientists working on biochar form a team of experts in soil science, carbon sequestration, agroecology, forestry and climate change.

Dr Lukas Van Zwieten is a Senior Research Scientist with NSW Department of Primary Industries, located at Wollongbar Agricultural Institute since 1995. Recent work on biochar is Internationally Acclaimed and won the 2007 World Environment Day Award “Meeting the Greenhouse Challenge.” Biochar research also received a Commendation from the NSW Premier’s Public Sector Awards. The research directly supports production of renewable energy and climate change mitigation through C sequestration in soil, increased crop production and reduced emissions of soil greenhouse gases into the atmosphere.

Dr Steve Kimber is part of the Environmental and Agricultural Health team at Wollongbar.
He joined NSW Agriculture in 1997 as an Environmental Scientist (pesticides) and has undertaken research in reducing off-site movement of pesticides, enhanced pesticide degradation and contaminated site risk assessment. He has over 15 years scientific research experience in the degradation and movement of pesticides, and in analytical residue chemistry. He is currently carrying out research on the benefits of biochar amendment to soils, in particular, the influence of biochar on greenhouse gas emissions.

Dr Annette Cowie is a Senior Research Scientist in DPI’s Science and Research Division. She leads the New Forests research program in the Forest Resources Research unit. The New Forests program demonstrates and quantifies environmental services from planted forests, particularly in the areas of carbon sequestration, salinity mitigation and land rehabilitation. Dr Cowie has a background in soil and plant science and her personal research program focuses on key aspects of greenhouse science: documenting greenhouse mitigation benefits of forestry systems for carbon sequestration and production of biofuel; management of soil carbon, including soil amendment with biochar to sequester carbon and enhance productivity; and development of greenhouse accounting systems for emissions trading. Dr Cowie is the Australian National Team Leader for IEA Bioenergy Task 38 “Greenhouse gas balances of biomass and bioenergy systems”, and has recently become Co-leader of the International Task Group.

Dr Yin Chan has been a principal research scientist of Department of Primary Industries since 1996 carrying out research in the area of soil physics, soil structure, soil physical fertility. He joined NSW Agriculture* in 1979 and has undertaken state-wide research on identifying and amelioration of soil physical problems of agricultural soils of the NSW, working closely with agronomists in the Department. Research projects taken include: understanding the processes of soil structural degradation, identification of physical limiting factors limiting crop production in NSW soils, their amelioration with the use of gypsum, lime, and improved management practices in terms of more suitable tillage practices, better rotation, incorporation of pasture phase, conservation tillage, ecology of earthworm and role in agroecosystems. As many of the soil physical constraints are directly related to declining soil organic carbon levels of many NSW soils, Yin Chan's current research projects - which involve farming system experiments in different parts of the State - concern the effect of management practices on (i) soil organic carbon dynamics and sequestration mechanisms (quantity & quality i.e. different carbon fractions); (ii) soil structure and soil organic carbon relationship (iii) improvement of soil biological activities, particularly the earthworms (iv) beneficial use of recycled organics in agriculture.

Dr Bhupinderpal Singh joined Forest Resources Research in August 2005 as a Research Officer and is currently working as a Research Scientist since August 2006. Dr Singh works in the New Forests group. This group quantifies environmental services from planted forests, particularly in the areas of carbon sequestration, salinity mitigation and land rehabilitation. Dr Singh's research focuses on quantifying: (i) biochar-carbon stability and greenhouse mitigation benefits of biochar application to soil; (ii) tree and soil respiration and their responses to climate change factors (such as elevated CO2, water availability); and (iii) in-situ non-CO2 (N2O, CH4) greenhouse gas emissions and their drivers, as well as soil C stock changes, during the transition from pasture to plantation forests in Australia. He is particularly interested in application of isotopes (especially 13C, 15N) to gain insights into soil organic C and N dynamics and belowground carbon cycling processes in Australian forest ecosystems.

Image: biochar field trials at the NSW DPI agricultural research station in Wollongbar. Pictured is Dr Lucas Van Zwieten.

References:

NSW Department of Primary Industries: Biochar revolution to benefit climate and agriculture - September 2, 2008.



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Tuesday, September 02, 2008

Scientists find signals of climate 'tipping points' in the past - relevance for carbon-negative energy

In the Earth’s history, periods of relatively stable climate have often been interrupted by sharp transitions to a contrasting state. For instance, glaciation periods typically ended suddenly. About 34 million years ago the Earth’s long lasting tropical state in which most recent life forms evolved, shifted abruptly and irreversibly to a cooler state with ice caps. This shift is known as the "Greenhouse-Icehouse-Transition". Scientists long suspected that such sharp transitions - called "Abrupt Climate Change" (ACC) events - might be related to tipping points where positive feedback mechanisms lead to self-propelling change. They have now found typical warning signals that preceded the onset of such ACC events in the past. The findings are highly relevant to the current debate about how to mitigate climate change, and to the question of whether we should prepare for ACC.

The threat of ACC events is very important to the bioenergy community, because it is widely recognized that only biomass-based energy systems are capable of mitigating such potential cataclysms. Scientists from the Abrupt Climate Change Strategy group (ACCS) were tasked to develop several scenarios and technological pathways that show how we can deliver carbon-negative energy which rapidly takes CO2 out of the atmosphere and brings us back to pre-industrial atmospheric CO2 levels - possibly our only shot at reversing approaching ACC events without radically powering down our societies (previous post). Carbon-negative bioenergy yields negative emissions, whereas all other energy technologies result in more carbon dioxide ending up in the atmosphere (illustration, click to enlarge). Even a rapid shift to carbon-neutral energy technologies would not suffice to reverse the threat of ACC.

To describe the tipping points which cause ACC events, researchers often use the example of the ice-albedo feedback. If ice caps melt, more sunlight is absorbed by the darker surface that is exposed. This causes further warming. Eventually, a rapid warming process that is irreversible and self-sustaining occurs. Although such mechanisms are well known, it was difficult so far to determine whether these feedbacks were strong enough to cause "tipping points".

A team of Dutch and German scientists around Marten Scheffer from Wageningen University and Hermann Held from the Potsdam Institute for Climate Impact Research has now analyzed the geological records of eight ancient events of abrupt climate change. These are the end of the greenhouse Earth, the end of the Younger Dryas, the Bølling-Alleröd-Transition, the desertification of North Africa and the ends of four glaciation periods.

In an article in the current online edition of the Proceedings of the National Academy of Sciences the researchers now report that sharp climatic shifts in the past were systematically preceded by subtle alterations in fluctuation patterns. These alterations are proven to be characteristic of systems approaching tipping points. This finding supports the theory that the sharp climatic shifts in the past have happened as the Earth system went over critical thresholds where self-catalyzing change pushed it further towards a contrasting state.

The demonstration of tipping points has implications for the thinking about current climate change, the authors state. The well known projections by the Intergovernmental Panel on Climate Change (IPCC) are based on the assumption of rather linear change:
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But although some feedbacks in the Earth system may dampen change, the new results imply that we should also consider the possibility that the climate will cross a tipping point after which changes will be amplified and end up in abrupt alterations.

Whether climate as a whole is now approaching a tipping point is difficult to judge with the new techniques. This is because human influence is simply too fast to generate data records long enough for the detection method. However, for certain parts of the climate system the method may be readily applicable to predict future abrupt change.

References:
Vasilis Dakos, Marten Scheffer, Egbert H. van Nes, Victor Brovkin, Vladimir Petoukhov, and Hermann Held, "Slowing down as an early warning signal for abrupt climate change", PNAS early online publication, September 2008 [not yet online].

P. Read and J. R. Lermit, "Bio-energy with carbon storage(BECS): a sequential decision approach to the threat of abrupt climate change" [*.pdf], Energy, November 2005, vol. 30, no14, pp. 2654-2671

Biopact: Research warns 'dangerous climate change' may be imminent - carbon negative bioenergy now - May 31, 2007

Biopact: Carbon-negative bioenergy making headway, at last - June 06, 2008


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Biofuels and biopharmaceuticals meet: scientists develop safe and inexpensive alternative to antibiotics in production of biotech products

Researchers at Sweden's Karolinska Institute and at the Royal Veterinary College (RVC) in London have developed a system that eliminates the need for antibiotics and resistance genes in the engineering of industrial and medical products. The method involves safer, less costly alternatives and is well suited for industrial production of many types of biofuels and biopharmaceuticals. The research has been published as an open access article in BMC Biotechnology.

Antibiotic resistance genes are widely used for selection of recombinant bacteria for use in biotechnology, but their use risks contributing to the spread of antibiotic resistance, particularly as biotechnology products move into the environment and the clinic. In particular, the practice is inappropriate for some intrinsically resistant bacteria and in vaccine production, and costly for industrial scale production. Non-antibiotic systems are available, but require mutant host strains, defined media or expensive reagents.

Gene targeting is the insertion of DNA into specific sites or genes within the genome of selected cells in order to alter gene expression for a particular purpose.

While working on gene targeting in bacteria, the researchers discovered that a well-known interaction between a cell membrane synthesis gene and the biocide triclosan could be exploited for strain selection. Surprisingly, triclosan selection performs better than conventional antibiotic selection:
We think this simple technology is well suited for industrial scale fermentations that produce a range of valuable products, including bio-fuels and bio-pharmaceuticals. More importantly, the new system is relatively safe and inexpensive, because the gene is native in all bacteria and triclosan is approved for use in many household applications. - Dr Liam Good, Royal Veterinary College and lead researcher on the project
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The new cloning vector, pFab, enabled selection by triclosan at 1 μM. Interestingly, pFab out-performed the parent pUC19-ampicillin system in cell growth, plasmid stability and plasmid yield. Also, pFab was toxic to host cells in a way that was reversed by triclosan. Therefore, pFab and triclosan are toxic when used alone but in combination they enhance growth and plasmid production through a gene-inhibitor interaction.

The fabI-triclosan model system thus provides an alternative plasmid selection method based on essential gene over-expression, without the use of antibiotic-resistance genes and conventional antibiotics.

The research was carried out with Dr Shan Goh of the Department of Cell and Molecular Biology of the Karolinska Institute, Stockholm.

References:
Shan Goh and Liam Good, "Plasmid selection in Escherichia coli using an endogenous essential gene marker", BMC Biotechnology 2008, 8:61, doi:10.1186/1472-6750-8-61.


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South Korea Minister: "biomass most important of all renewables"

It is very rare for a policy maker to explicitly say which of the future energy sources he thinks will be the most important. Most politicians would prefer to remain technology neutral. But in South Korea, Knowledge & Economy Minister Lee Yoon-Ho was asked the question by parliament, requiring him to make a choice. His answer: biomass and bioenergy will be "the most important and useful amongst new sources of renewable energy for a significant time in the future".

The minister made the remarks on Tuesday in a plenary session of the parliamentary committee on knowledge and economy. Lee was answering Grand National Party lawmaker Kang Yong-seok’s questions on the efficiency of renewable energy sources.

The minister compared renewable technologies such as solar, wind, small hydro and biomass . The latter clearly stood out, even though Lee Yoon-Ho gave no list of reasons as to why he thinks this is so.

There are some obvious advantages to bioenergy, though, making his choice rather self-evident:
  • biomass offers reliable baseloads, as it is stored solar energy; other renewables are intermittent and thus rely on an outside source of energy in order to deliver energy round the clock. Currently, there are no efficient energy storage options for wind or solar
  • biomass is the only renewable energy source capable of providing renewable heat in an efficient manner (co-generation, district heating, household boilers); in many highly developed countries (like South Korea) heating is both the most difficult as well as the sector with the biggest need for renewable energy
  • biomass can make use of existing infrastructures, such as coal and gas power plants and their fuel handling infrastructures, as well as gas pipelines and coal supply chain infrastructures
  • biomass can be physically transported and traded, because it is stored solar energy. This makes it possible to plan and optimise energy production at sites that need reliable baseloads and where there is a lack of space for other renewables. Trading biomass also allows power producers to import fuels from countries where the production would yield major environmental or social benefits, or from places where a low-cost supply is available.
  • a single source of biomass can be converted into a wide range of products, from green platform chemicals to liquid, gaseous and solid fuels; this flexibility gives energy crop growers a range of strategic options which can maximise value
  • energy crops can help to restore the environment; they can be grown to perform key ecosystem services, such as curbing erosion and desertification, re-greening deforested areas, restoring soil health, and most importantly, sequestering carbon
  • biomass can become carbon-negative, that is, systems can be designed that actively remove CO2 from the atmosphere (by geosequestering biogenic CO2 or by sequestering biochar in soils); all other renewables on the contrary remain carbon-positive over their lifecycle
  • last but not least, biomass is by far the least costly of all renewables, easing the economic challenge of making a transition to clean energy and making it possible to serve the poor, who are always the first to suffer under higher energy prices
Obviously, the story of renewable energy is not one of pitting one technology against another one. On the contrary, renewables can be coupled to each other, and, with biomass delivering strong baseloads, replace all our fossil fuel based energy production in an affordable and efficient way [entry ends here].

Picture: Miscanthus x giganteus pellets, used in power plants in Europe.
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Monday, September 01, 2008

Carbon emissions from thawing permafrost could be larger than previously thought

The thawing of permafrost in northern latitudes, which greatly increases microbial decomposition of carbon compounds in soil, will dominate other effects of warming in the region and could become a major force promoting the release of carbon dioxide and thus further warming, according to a new assessment [*.pdf] in the September 2008 issue of BioScience.

The study, by Edward A. G. Schuur of the University of Florida and an international team of coauthors, more than doubles previous estimates of the amount of carbon stored in the permafrost: the new figure is equivalent to twice the total amount of atmospheric carbon dioxide. The authors conclude that releases of the gas from melting permafrost could amount to roughly half those resulting from global land-use change during this century.

Schuur and his colleagues refine earlier assessments by considering complex processes that mix soil from different depths during melting and freezing of permafrost, which occur to some degree every year. They judge that over millennia, soil processes have buried and frozen over a trillion metric tons of organic compounds in the world's vast permafrost regions.

The relatively rapid warming now under way is bringing the organic material back into the ecosystem, in part by turning over soil. Some effects of permafrost thawing can be seen in Alaska and Siberia as dramatic subsidence features called thermokarsts (pictures, click to enlarge).

The researchers acknowledge many difficulties in estimating carbon dioxide emissions from permafrost regions, which hold more carbon in the Arctic and boreal regions of the Northern Hemisphere than in the Southern Hemisphere. Data are limited, and emissions are influenced by the amount of surface water, topography, wildfires, snow cover, and other factors. Thawing, although believed to be critical, is hard to model accurately:
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Some warming-related trends in Arctic regions, such as the encroachment of trees into tundra, may cause absorption of carbon dioxide and thus partly counter the effects of thawing permafrost. But Schuur and colleagues' new assessment indicates that thawing is likely to dominate known countervailing trends.

References:

Edward A. G. Schuur et. al. "Vulnerability of Permafrost Carbon to Climate Change: Implications for the Global Carbon Cycle", BioScience, September 2008 / Vol. 58 No. 8.

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Sunday, August 31, 2008

Scientists discover key to cold tolerance in corn - longer growing season, growth in colder regions possible for tropical crops

Demand for corn - the world's number one feed grain and a staple food for many - is outstripping supply, resulting in large price increases that are forecast to continue over the next several years. Part of the reason for this state of things is the heavy reliance of the U.S. biofuels industry on corn. However, if this crop's intolerance of low temperatures could somehow be overcome, then the length of the growing season, and yield, could be increased at present sites of cultivation and its range extended into colder regions.

Drs. Dafu Wang, Archie Portis, Steve Moose, and Steve Long in the Department of Crop Sciences and the Institute of Genomic Biology at the University of Illinois may have made a crucial breakthrough on this front, as reported in the September issue of the journal Plant Physiology. Interestingly, their discovery goes beyond corn and may make it possible to breed highly productive food and energy crops like sugar cane in such a way that they can grow at higher latitudes.

Plants can be divided into two groups based on their strategy for harvesting light energy: C4 and C3. The C4 groups include many of the most agriculturally productive plants known, such as corn, sorghum, and sugar cane. All other major crops, including wheat and rice, follow the C3 pathway. C4 plants differ from C3 by the addition of four extra chemical steps, making these plants more efficient in converting sunlight energy into plant matter.

Until recently, the higher productivity achieved by C4 species was thought to be possible only in the warm environments of the tropics and the subtropics. So while wheat, a C3 plant, may be grown into northern Sweden and Alberta, the C4 grain corn, essentially a tropical plant, cannot. Even within the American Corn Belt and despite record yields, corn cannot be planted much before early May and as such is unable to utilize the high sunlight of spring.

Recently a wild C4 grass related to corn, Miscanthus x giganteus, has been found to be exceptionally productive in cold climates and has therefor drawn attention as a bioenergy crop (previous post). The Illinois researchers set about trying to discover the basis of this difference, focusing on the four extra chemical reactions that separate C4 from C3 plants.

Each of these reactions is catalyzed by a protein or enzyme. The enzyme for one of these steps, Pyruvate Phosphate Dikinase, or PPDK for short (see ribbon diagram, click to enlarge), is made up of two parts:
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At low temperature these parts have been observed to fall apart, differing from the other three C4 specific enzymes. The researchers examined the DNA sequence of the gene coding for this enzyme in both plants, but could find no difference, nor could they see any difference in the behavior of the enzyme in the test tube. However, they noticed that when leaves of corn were placed in the cold, PPDK slowly disappeared in parallel with the decline in the ability of the leaf to take up carbon dioxide in photosynthesis. When Miscanthus leaves were placed in the cold, they made more PPDK and as they did so, the leaf became able to maintain photosynthesis in the cold conditions. Why?

The researchers cloned the gene for PPDK from both corn and Miscanthus into a bacterium, enabling the isolation of large quantities of this enzyme. The researchers discovered that as the enzyme was concentrated, it became resistant to the cold, thus the difference between the two plants was not the structure of the protein components but rather the amount of protein present.

The findings suggest that modifying corn to synthesize more PPDK during cold weather could allow corn, like Miscanthus, to be cultivated in colder climates and be productive for more months of the year in its current locations. The same approach might even be used with sugar cane, which may be crossed with Miscanthus, making improvement of cold-tolerance by breeding a possibility.

Image: ribbon diagram of the enzyme Pyruvate Phosphate Dikinase, which, the scientists found, plays the key role in the exceptional cold tolerance of Miscanthus. Credit: Theoretical and Computational Biology Group, The Laboratory of Molecular Biology, University of Cambridge.

References:
Dafu Wang, Archie R. Portis, Jr, Stephen P. Moose, and Stephen P. Long, "Cool C4 Photosynthesis - Pyruvate Pi Dikinase Expression and Activity Corresponds to The Exceptional Cold Tolerance of Carbon Assimilation in Miscanthus x giganteus", Plant Physiol. First published on June 6, 2008; DOI: 10.1104/pp.108.120709

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