November 2007, Vol. 19, No.11


High-Tech Tools Tackle Agricultural Management

 New tools developed by U.S. Agricultural Research Service (ARS) scientists are helping farmers and managers make better-informed decisions by assessing the economic and ecological outcomes of different management practices. Understanding the incentives that lead farmers to embrace conservation could help program developers, researchers, and policy-makers transfer conservation technology more successfully, according to an ARS news release.

Profitable environmental management relies on a variety of factors, and balancing economic and ecological interests can be challenging, ARS states. To assist managers in this task, Jason Bergtold, an economist at the ARS National Soil Dynamics Laboratory in Auburn, Ala., is working with colleagues to develop two user-friendly tools — an economic model and a farm payment calculator. The Conservation Systems Learning Tool model predicts how profitable various crops will be under different management systems. The Crop Profitability Calculator evaluates how such factors as conservation incentive payments and practices influence the profitability of crop enterprises.

Bergtold’s research also investigates whether conservation practices are being accepted, maintained, or intensified, and why. He and his colleagues have nearly completed a study that examines how such factors as demographics, farm characteristics, management practices, and personal beliefs influence southeastern U.S. farmers who could qualify for economic support by adopting conservation practices, according to the news release.

Jerry Whittaker, a hydrologist in the ARS Forage, Seed, and Cereal Research Unit in Corvallis, Ore., is helping develop a two-model system to evaluate conservation practices. First, an economic model chooses different management decisions, such as the amount of chemicals to apply. Then that information is fed into the second model to evaluate the environmental effects of different economic decisions.

Whittaker is also speeding up economic analysis with a massive, custom-made parallel computer called a “Beowulf cluster.” This is a very large, very fast, problem-solving computer — or rather, a cluster of inexpensive computers linked via Ethernet.

For more information, contact Whittaker at or Bergtold at, or read an article on the research in the July 2007 issue of Agricultural Research magazine at

Scientists Convert Poultry Litter Into Bio-Oil

Foster Agblevor, associate professor of biological systems engineering at the College of Agriculture and Life Sciences at Virginia Polytechnic Institute and State University (Blacksburg, Va.), is leading a team of researchers in  developing transportable pyrolysis units that will convert poultry litter into bio-oil. The bio-oil, according to a university news release, will provide a cost-effective disposal system while reducing environmental effects and biosecurity issues.

Agblevor is working with poultry growers to test technology that would convert poultry litter to three value-added byproducts — pyrodiesel (bio-oil), producer gas, and fertilizer. The pyrolysis unit heats the litter until it vaporizes. The vapor is then condensed to produce the bio-oil, and a slow-release fertilizer is recovered from the reactor. The gas then can be used to operate the pyrolysis unit, making it a self-sufficient system, the news release notes.

The bio-oils had relatively high nitrogen content, ranging from 4% to 7% by weight, very low sulfur content — less than 1% by weight — and were very viscous. The char yield ranged from 30% to 50% by weight, depending on the source, age, and composition of the poultry litter. The char also had high ash content, ranging from 30% to 60% by weight, depending on the age and source of litter.

The research is part of a concentrated effort by the university research team, Virginia Cooperative Extension specialists and agents, conservation organizations, state agencies, and private industry to determine the most effective means to support the agricultural community and manage the excess nutrients in the Shenandoah Valley. The research is being funded by a $1 million grant from the Chesapeake Bay Targeted Watershed Program of the National Fish and Wildlife Foundation (Washington, D.C.).

Contact Agblevor at  

Extreme Weather Monitoring Boosted by Space Sensor

The first soil-moisture maps with a spatial resolution of 1 km (0.6 mi) are available online for the entire southern African subcontinent. As soil moisture plays an important role in the global water cycle, these maps, based on data from the European Space Agency (ESA; Paris) Envisat satellite, will lead to better weather and extreme-event forecasting, such as floods and droughts, according to an ESA news release.

“Predicting when and where floods are likely to happen is becoming more and more important,” said Geoff Pegram of the University of KwaZulu–Natal (Durban, South Africa). “Although we cannot prevent floods, we can anticipate them and hopefully get people out of the way.”

Despite its importance for agricultural planning and weather forecasting, there has been a lack of soil-moisture information in Africa because of the high costs of in situ measurement networks, according to ESA. In addition, unlike satellite observations, point-based measurements are often not sufficient to provide an overall picture over large areas that may be effectively used in models.

The ESA-backed SHARE (Soil Moisture for Hydrometeorological Applications in the Southern African Development Community Region) project, funded through ESA’s Data User Element, is the first to demonstrate that spaceborne synthetic aperture radar instruments can deliver soil-moisture data of high spatial (1 km or 0.6 mi) and temporal (less than 1 week) resolution.

The SHARE project team combines expertise in soil-moisture remote sensing from Austria’s Vienna University of Technology with specialists in hydrometeorological applications from the University of KwaZulu-Natal.

SHARE concluded its preoperational stage last month and will now seek funding and support from African organizations.

Water Stars in Film Competition

 Water played a starring role in a short film competition called “The Intelligent Use of WaterTM,” which was held this fall. According to sponsor Rain Bird Corp. (Azusa, Calif.), the competition gave filmmakers the opportunity to showcase their talents and bring about a greater awareness of the need for water conservation.

Filmmakers were invited to create a narrative, documentary, animated, experimental, or student-made film exploring approaches and ideas to intelligently manage and efficiently use water. While the competition drew many filmmakers, Rain Bird, a manufacturer and provider of irrigation products and services, said that professionals in the water field also were invited to share their expertise.

“Our panel of judges shares our steadfast belief that the solution to the world’s current and future water scarcity problems lies in the education, mobilization, and involvement of the public,” said Dave Johnson, Rain Bird’s corporate marketing director. “The competition enables people to exercise their influence and raise awareness of this important issue while providing a public forum for supporting, discovering, and showcasing filmmaking talent.”

Judges ranged from cinematic professionals, such as representatives of the American Cinema Foundation (Los Angeles) and the American Film Institute (Los Angeles), to experts in the water field, such as Linda Adams, secretary of the California Environmental Protection Agency and former director of the California Department of Water Resources; and Robert Glennon, a professor at the University of Arizona’s (Tucson) Rogers College of Law and author of Water Follies: Groundwater Pumping and the Fate of America’s Fresh Waters.

The winner, announced in October, was not available at press time. For more information, see

Sunspot Abundance Linked to Heavy Rains in East Africa

A new study reveals correlations between plentiful sunspots and periods of heavy rain in East Africa. Intense rainfall in the region often leads to flooding and disease outbreaks, according to a news release issued by the American Geophysical Union (AGU; Washington, D.C.).

The analysis by a team of U.S. and British researchers shows that unusually heavy rainfalls in East Africa during the past century preceded peak sunspot activity by about 1 year. Because periods of peak sunspot activity, known as solar maxima, are predictable, so too are the associated heavy rains that precede them, the researchers propose.

The work counters previous research that found no connection between sunspot cycles and rainfall in East Africa.

“With the help of these findings, we can now say when especially rainy seasons are likely to occur, several years in advance,” said paleoclimatologist and study leader Curt Stager of Paul Smith’s College (Paul Smiths, N.Y.). Forewarned by such predictions, public health officials could ramp up prevention measures against insectborne diseases long before epidemics begin, he added.

The sunspot–rainfall analysis appeared in the Aug. 7 Journal of Geophysical Research — Atmospheres, an AGU publication.

Stager and colleagues offer several reasons why sunspot peaks may affect rainfall. In a simple scenario, increased solar energy associated with sunspots heats both land and sea, forcing moist air to rise and triggering precipitation.

While sunspot peaks augur extraordinarily wet rainy seasons, heavy rains also are possible at other times, Stager acknowledges. However, most of the rainiest times, Stager said, are consistently coupled with the predictable rhythms of sunspot peaks. And, to be forewarned is to be forearmed, AGU notes.
For more information, contact Stager at