Norwegian Wood For The Ages: 'Mummified' Pine Trees Found

Norway’s wet climate seems perfect for encouraging organic matter to rot – particularly in Sogndal, located on Norway’s southwestern coastline, in one of the most humid, mild areas of the country. In fact, with an average of 1541 millimetres of rain yearly and relatively mild winters, Sogndal should be an environment where decomposition happens fast. Not so.

“We were gathering samples of dead trees to reconstruct summer temperatures in western Norway, when our dendrochronological dating showed the wood to be much older than expected”, says Terje Thun, an associate professor at the Norwegian University of Science and Technology’s (NTNU) Museum of Natural History and Archaeology. Thun conducted the work with his colleague Helene Løvstrand Svarva.

From a time before the Black Death

“We were astounded to find fresh wood in trees that started to grow in the late 1200s and had died almost 500 years ago, which is much older than we originally expected. Somehow they have kept from decomposing for several centuries in this humid climate”, Thun says. “This is quite extraordinary - I would go as far as to call it sensational.”

Thun says that when a pine tree dies, it secretes a great deal of resin, which deters the microorganisms needed for decomposition. “Nevertheless, preventing the natural breakdown of the wood for centuries is quite a feat”, he says. Thun is one on Norway’s leading dendrochronology experts. Dendrochronology is the dating of trees.

Used in mummification

Resin was one of the ingredients used in Ancient Egypt for mummification, so its conservation abilities have been known for millennia. However, that trees could “self-mummify” in such a humid climate for centuries was new to the NTNU scientists.

“Many of the trunks we dated turned out to have seeded in the early 1200s, and had lived for more than 100 years at the time of the Black Death around 1350”, Thun says. “That means that the dead wood has ‘survived’ in nature for more 800 years without breaking down.”

It seems there truly is something good about Norwegian wood.

Genetic Map For Cowpea Accelerates Development Of New Varieties

Cowpea provides food that complements starchy staple crops such as corn, cassava, sorghum and millets to offer a well-rounded diet, much as beans and other grain legumes complement maize- and rice-based diets in Latin America and other places. Due to its hardy nature, cowpea plays a key role in sustaining food security for both people and their livestock.

But breeding new cowpea varieties with desirable traits, such as disease resistance, pest resistance and drought tolerance, is a time-consuming and laborious process that can take a decade from concept to release.

A challenge facing cowpea breeders, therefore, is how to accelerate the production of new and improved cowpea varieties in order to both meet the needs of a growing world population and provide the productivity gains needed by farmers to improve their economic standing.

Now a team of scientists at the University of California, Riverside has responded to this challenge by developing a high-density "consensus genetic map" of cowpea that accelerates conventional breeding severalfold and facilitates the production of new varieties of not only cowpea but also other legumes, particularly soybean and common bean (near relatives of cowpea).

To build the map, the scientists first modified and then applied advanced genetic tools developed from human genome investigations that only recently have been applied to a few major crop plants.

"The consensus map is a consolidation of six individual genetic maps of cowpea, and is far more representative of the cowpea genome than earlier maps," said team leader, Timothy Close, a professor of genetics in the Department of Botany and Plant Sciences. "We now have a reliable, powerful tool that marks a paradigm shift in crop-breeding technology."

Study results appear Oct. 13 in the online early edition of the Proceedings of the National Academy of Sciences.

The consensus genetic map of cowpea is a dense and detailed roadmap of its genome (a genome is a complete genetic blueprint). The map has approximately 1000 molecular markers throughout the genome. The markers, which are like signposts directing a motorist to a destination, are associated with traits desired for breeding and used to more deliberately design and assemble new superior varieties.

"All you need is a marker near a gene of interest," explained team member Philip Roberts, a professor in the Department of Nematology, who currently leads UCR's Bean/Cowpea and Dry Grain Pulses Collaborative Research Support Program — a highly successful project, supported by the U.S. Agency for International Development, that has assisted African institutes in developing improved cowpea varieties. "With a marker-based map we can look into any trait desired in cowpea. The resolution of the map is such that we can accurately locate the position of genes that are contributing in a major way to various traits we'd like to see built into new cowpea varieties."

Close explained that cowpea is closely related to soybean at the genome level, allowing for the kind of cross referencing that would have been unfeasible without the consensus genetic map.

"A good number of genes are conserved across species," he said. "By looking at a marker on a cowpea chromosome, we can cross reference it to information on, say, the soybean genome, based on the DNA sequences of the marker. This facilitates knowledge transfer between these species, so advances made in cowpea can be translated into valuable information for soybean, and vice versa. The result is a tremendous acceleration in marker development to support the breeding process."

Cowpea, which originated in Africa, also is commonly referred to as southern pea, blackeye pea, crowder pea, lubia, niebe, coupe or frijole. In the United States, cowpea is popular in the south, where it is known as black-eyed peas and other names. California primarily grows the blackeyed cowpea type.

"It took us nearly ten years to breed 'California Blackeye No. 50,' our newest blackeye cowpea variety for California growers, using conventional breeding methods," said Jeff Ehlers, a specialist in the Department of Botany and Plant Sciences with more than 20 years of experience conducting genetic research on cowpea in California and Africa. "With the new technologies and map information now at hand this could have been done in half this time. The new consensus map will greatly expand our ability to locate valuable genes and incorporate them into new varieties."

UCR is host to a collection of more than 5,000 cowpea varieties from around the world. These genetically diverse varieties offer a treasure-trove of genes of potential value to breeders seeking to build better cowpea varieties.

UCR researchers have been providing assistance to African scientists for several decades. In the late 1970s, Anthony Hall, a professor emeritus of crop physiology in the Department of Botany and Plant Sciences, pioneered research on cowpea at UCR. His research on cowpea physiology contributed to a deeper understanding of the legume's adaptation to drought, heat and poor soils, and his efforts with several African breeders helped develop highly successful varieties in Senegal, Sudan and Ghana. He also led the effort to establish a genetic map for cowpea, published in 1997.

Close, Roberts and Ehlers were joined in the research by UCR's Wellington Muchero, the first author of the research paper, and Ndeye Diop, both of whom are postdoctoral researchers and hail from Africa, as well as Prasanna Bhat, Raymond Fenton, Steve Wanamaker, and Marti Pottorff. Other coauthors on the research paper are Sarah Hearne and Christian Fatokun of the International Institute of Tropical Agriculture, Nigeria, and Ndiaga Cisse of the Senegalese Institute of Agricultural Research.

The two-year research effort was funded by the Generation Challenge Program (GCP) through a grant to the GCP from the Bill and Melinda Gates Foundation, and from the U.S. Agency for International Development-funded Collaborative Research Support Program.

Impacts of Global Biofuel Boom Remain Murky

A U.N. panel said today that biofuels' effects on air and water have not been sufficiently explored despite growing global production.

The U.N. Environment Programme's report concludes that so-called lifecycle assessments must go beyond calculating greenhouse gas emissions and consider how agricultural production of feedstocks affect the acidification and nutrient loading of waterways.

"The available knowledge from life-cycle-assessments ... seems limited, despite the fact that for those issues many biofuels cause higher environmental pressures than fossil fuels," the report says.

"From a representative sample of [lifecycle] studies on biofuels, less than one third presented results for acidification and eutrophication, and only a few for toxicity potential (either human toxicity or eco-toxicity, or both), summer smog, ozone depletion or abiotic resource depletion potential, and none on biodiversity," it adds.

The study is the second major report this month calling for greater research on the environmental effects of producing ethanol and other renewable transportation fuels.

A Government Accountability Office report released Oct. 2 said Congress should require U.S. EPA to consider a wider range of environmental effects when deciding which fuels are eligible under the federal biofuels use mandate (E&ENews PM, Oct. 2).

The topic is one of many covered in the broad UNEP survey of issues surrounding "sustainable" production and use of biofuels and notes wide variation in greenhouse gas emissions reductions and increases that biofuels can spur.

It warns that some biofuels production methods can cause large increases in greenhouse gas emissions, such as clearing Indonesian rainforest to grow palm plantations for biodiesel.

The study examines options for lessening the effects of expanding agricultural production prompted by fuels, such as using currently marginal or degraded land for fuels feedstock production.

The report is the product of UNEP's International Panel for Sustainable Resource Management.

"Biofuels are neither a panacea nor a pariah but like all technologies they represent both opportunities and challenges," Achim Steiner, U.N. undersecretary-general and UNEP executive director, said in a statement.

"Therefore a more sophisticated debate is urgently needed which is what this first report by the Panel is intended to provide," he added. "On one level, it is a debate about which energy crops to grow and where, and also about the way different countries and biofuel companies promote and manage the production and conversion of plant materials for energy purposes -- some clearly are climate friendly while others are highly questionable."

Biofuels use in the United States and elsewhere has grown considerably in recent years. Global ethanol production tripled between 2000 and 2007 from 17 billion to more than 52 billion liters. Biofuels still provide 1.8 percent of transportation fuels globally.

Growth in biofuels production and use is driven by mandates in many countries. The United States expanded its federal biofuels mandate in a 2007 law to reach 36 billion gallons by 2022, with up to 15 billion gallons coming from corn ethanol and the balance from so-called advanced biofuels like cellulosic ethanol.

However, these next-wave fuels have not yet reached commercial-scale production, although a number of projects are under development.

 Smithsonian researchers working in Colombia's Cerrejón coal mine have unearthed the first megafossil evidence of a neotropical rainforest. Titanoboa, the world's biggest snake, lived in this forest 58 million years ago at temperatures 3-5 C warmer than in rainforests today, indicating that rainforests flourished during warm periods.
"Modern neotropical rainforests, with their palms and spectacular flowering-plant diversity, seem to have come into existence in the Paleocene epoch, shortly after the extinction of the dinosaurs 65 million years ago," said Carlos Jaramillo, staff scientist at the Smithsonian Tropical Research Institute. "Pollen evidence tells us that forests before the mass extinction were quite different from our fossil rainforest at Cerrejón. We find new plant families, large, smooth-margined leaves and a three-tiered structure of forest floor, understory shrubs and high canopy."
Historically, good rock exposures and concentrated efforts by paleontologists to understand the evolution of neotropical rainforests—one of the most awe-inspiring assemblages of plant and animal life on the planet—have been lacking. "The Cerrejón mining operation is the first clear window we have to see back in time to the Paleocene, when the neotropical rainforest was first developing," said Scott Wing, a paleontologist from the Smithsonian's National Museum of Natural History.
Some of the more than 2,000 fossil leaves, including the compound leaves and pods of plants in the bean family and leaves of the hibiscus family are among the oldest, reliable evidence of these groups. This was the first time that the plant families Araceae, Arecaceae, Fabaceae, Lauraceae, Malvaceae and Menispermaceae, which are still among the most common neotropical rainforest families, all occurred together.
Many newcomers to modern rainforests remark that the leaves all look the same, a reasonable observation given that most have smooth margins and long "drip-tips" thought to prevent water from accumulating on the leaf surface.
S. Joseph Wright, senior scientist at STRI, has noted that all of the areas in the world today with average yearly temperatures greater than 28 C are too dry to support tropical rainforests. If tropical temperatures increase by 3 C by the end of this century as predicted in the 2007 report of the Intergovernmental Panel on Climate Change, "We're going to have a novel climate where it is very hot and very wet. How tropical forest species will respond to this novel climate, we don't know," said Wright.
Based on leaf shape and the size of the cold-blooded Titanoboa, Cerrejón rainforest existed at temperatures up to 30-32 C and rainfall averages exceeded 2500 mm per year.
But Titanoboa's rainforest was not as diverse as modern rainforests. Comparison of the diversity of this fossil flora to modern Amazon forest diversity and to the diversity of pollen from other Paleocene rainforests revealed that there are fewer species at Cerrejón than one would expect. Insect-feeding damage on leaves indicated that they could have been eaten by herbivores with a very general diet rather than insects specific to certain host plants.
"We were very surprised by the low plant diversity of this rainforest. Either we are looking at a new type of plant community that still hadn't had time to diversify, or this forest was still recovering from the events that caused the mass extinction 65 million years ago," said Wing. "Our next steps are to collect and analyze more sites of the same age from elsewhere in Colombia to see if the patterns at Cerrejón hold, and study additional sites that bracket the Cretaceous mass extinction, in order to really understand how the phenomenal interactions that typify modern rainforests came to be."