• Rising Seas Threaten Bay Marshes
  
• Tropical Forests Release Carbon Dioxide
  
• Agriculture, Interior Form Joint Fire Council
  
• Alcoa Grant Supports Forest Protection
  
• Not All Forest Clearings are Created Equal
  
• Compost Center Emissions Targeted for Cleanup
  
• Supercritical Carbon Dioxide Could Clean Hazardous Wastes
  
• Ultrasound Scrubs Water Filters
  
• Industry: U.S. Could Tap Vast Geothermal Energy Sources
  

Rising Seas Threaten Chesapeake Bay Marshes

Almost all coastal marshes along the Chesapeake and Delaware Bays could disappear before 2100, if the sea level continues to rise at present rates or the higher rates predicted by climate models, the new study suggests.

Loss of these marshes would be devastating, the researchers say, due to its effect on the food chain, water quality, and the amount of carbon that would be released into the oceans and atmosphere. Marshes act as carbon sinks, holding it in soils and vegetation and preventing the release of carbon dioxide gas.

The study, by Professor Michael Kearney and colleagues, appears in the April 16 issue of "Eos," a publication of the American Geophysical Union.

Kearney and his colleagues developed a new technique based on satellite images, aerial photography and field surveys. The model measures reflectance from the marsh's soil or sediment layer, its vegetation, and the water, in order to determine its Marsh Surface Condition Index (MSCI), which tracks the overall health of the marsh.

A key benefit of the MSCI is that it helps scientists focus on the role of long term sea level rise, without regard to annual variations caused by heavy storms and other short term events.

In the Chesapeake Bay, the greatest degradation of marshes has occurred in the middle portion of its eastern shore at Blackwater Wildlife Refuge. Marshes in the upper reaches of both bays are less degraded than the middle and lower reaches because they are recharged by sediments carried by rivers.

Impoundments that limit stream flows into the Delaware Bay from New Jersey have led to greater degradation of marshes on that shore than on the opposite Delaware shore.

From 1984 to 1993, the area of degraded marshes in Delaware Bay increased from 25 percent to 54 percent of total marshland, especially on the New Jersey shore. About 70 percent of marshland in both estuaries has now been affected, the researchers said.

Kearney noted that the processes affecting Chesapeake and Delaware Bays could also be at work in other parts of the Atlantic coast. If more marshes disappear, coastal ecosystems could be devastated, and the sediments now held by the marshes would erode into coastal waters.

Tropical Forests Release Carbon Dioxide

The findings suggest that such forests may not be as effective at absorbing excess CO2 as some scientists have believed.

The international research team calculated that a total of 900 million metric tons (about two trillion pounds) of carbon is given off by tropical forest waterways around the world each year. That number is comparable to, for example, about a fifth of the carbon dioxide generated each year by human activities such as deforestation and burning fossil fuels.

U.S. and Brazilian researchers use floating chambers to measure the flux of carbon dioxide from waters of the forest in the central Amazon basin. (Photo courtesy University of Washington)

The new calculations were made possible by a program, sponsored by the National Aeronautics and Space Administration (NASA), that gave the researchers access to detailed radar imagery available only in the last few years. That data was used in conjunction with river measurements from 13 expeditions to the Amazon in the 1980s and 1990s.

Many global carbon models come up short when using numbers that measure carbon dioxide in the air in and just above tropical forests. In contrast, Richey and his colleges said that with the new numbers for waterways, the amount of carbon dioxide absorbed by tropical forests is about the same as that being released.

"The land water connection appears to be far more important than anyone thought," Richey said.

Richey and his group determined that 20 percent of the carbon being released from streams and rivers was from aquatic processes, while the other 80 percent originated in the forest's soil and leaf litter.

As the material decomposes and is eaten by organisms including insects and fish, carbon dioxide is release from surface waters. The resulting "river breath," as Richey termed it, turns out to be a downstream movement of carbon from the forest.

"If you want to know where carbon from today's tropical forest goes, look a thousand kilometers downstream in 20 or 30 years," Richey said.

Agriculture, Interior Form Joint Fire Council

The council was formed in response to expanded federal fire efforts and new fire risk reduction strategies. The two federal agencies now employ 17,633 firefighters, up by more than 5,000 in the past two years, and coordinate hundreds of air tankers, fire engines and other heavy equipment.

The council includes land management officials from both departments, including the under secretary of Agriculture for natural resources and the environment and the chief of the U.S. Forest Service; the directors of the National Park Service, the Bureau of Land Management, and the U.S. Fish and Wildlife Service; the assistant secretary for Indian affairs and the chief of staff to the Interior Secretary.

"The objective of this council is to provide a coordinated seamless management structure to all aspects of wildland fire policy," said Agriculture Secretary Ann Veneman.

The council will work with state, local and tribal officials on wildland fire management policies, which may include reducing fuel loads on wildlands near populated areas. Some of the more controversial tactics sometimes authorized under the National Fire Plan include clearing underbrush and logging small trees.

After fires occur, the council will coordinate with state partners and local communities to help restore landscapes, rebuild communities, invest in projects to reduce fire risk and assess the economic needs of areas damaged by fire.

"This agreement formalizes the efforts already underway at Agriculture and Interior to coordinate our wildland fire management strategies and to ensure implementation of the National Fire Plan," Interior Secretary Gale Norton said. "Drought conditions are an indication that we could have an active season."

Last month, the federal Office of Management and Budget (OMB) released $348 million for Forest Service wildfire management and fire suppression.

"The release of these funds will have an immediate impact on the Forest Service's ability to coordinate the National Fire Plan as we move into the spring and summer months," said Idaho Governor Dirk Kempthorne. "Until OMB made these funds available, critical elements of our fire prevention strategy were not being funded and delays of high priority timber, hazardous fuel and construction projects were imminent."

Alcoa Grant Supports Forest Protection

The five forests are the mangrove forests of Brazil's Amazon basin, Meili Snow Mountain in China's Yunnan Province, the Blue River watershed in Indiana, Mexico's Ajos-Bavispe National Forest and government owned forests of Pennsylvania. The Alcoa Foundation is the charitable arm of aluminum giant Alcoa.

The grant will fund efforts by The Nature Conservancy and its local partners to protect forest ecology while ensuring that the development needs of local communities are met. Alcoa Foundation's grant will support ecoregional planning and community involvement, public education and outreach, land acquisition and stewardship of the sites.

"By supporting conservation related organizations like The Nature Conservancy, and programs that address crucial environmental challenges, Alcoa Foundation reinforces our commitment to conservation and sustainability," said Kathleen Buechel, president and treasurer of Alcoa Foundation. "These grants also complement Alcoa's goals of being a fully sustainable enterprise that makes the world a better place because of our activities."

In Brazil, the Alcoa grant will help provide conservation training to the managers of all protected areas along the Amazon River from Maranhão to Amapá. In the Blue River watershed of southern Indiana, Alcoa Foundation is supporting the launch of the Forest Bank, a market oriented approach to encouraging private landowners to harvest their timber using ecologically sound practices.

In China, the funds will support a project to cut the household consumption of fuel wood by 75 percent in the next 10 years by developing a range of alternative energy initiatives, such as micro-hydro, fuel efficient stoves, passive solar and biogas. The collection of wood for cooking and heating threatens forests around Meili Snow Mountain, and is a hardship to local women who bear the heavy burden of wood gathering.

Alcoa Foundation's support will help protect biological corridors linking isolated mountain top protected areas in Mexico's Ajos-Bavispe National Forest and Wildlife Refuge, one of the oldest protected areas in the Mexican state of Sonora.

In Pennsylvania, Alcoa Foundation is supporting the Conservancy's work to develop conservation plans and strategies for protecting forest areas and encouraging sustainable timber management practices on government owned lands.

"The Conservancy and Alcoa Foundation share a strong desire to make sure our conservation efforts improve the quality of life for the local communities involved," said Nigel Homer, acting director of Corporate Partnerships for the Conservancy. "Alcoa Foundation's support of these programs will help ensure that these communities will enjoy the benefits of majestic and diverse forest systems for many years to come."

Not All Forest Clearings are Created Equal

The study suggests that farming may make bird nests more vulnerable to predation by squirrels and other animals.

Amanda Rodewald, assistant professor of wildlife ecology in Ohio State's School of Natural Resources, found that forests with agricultural clearings in them had a lower diversity of bird species and fewer birds than forests in which pockets of tree cover had been cleared by timber harvesting.

"A farm patch in the forest may be more damaging to birds than a clearing left by just the felling of trees," said Rodewald, who did the study in collaboration with Richard Yahner, a professor of wildlife ecology at Penn State University. The researchers published their work in a recent issue of the journal "Ecology."

Rodewald said the results of the study could help forest managers make better decisions on strategies for conservation and forest management.

"Some parks and forests will allow small agricultural openings within them. Those are the types of management policies that we need to start reconsidering," Rodewald said. "It's not enough to say there are a lot of forests, so the birds in them will be fine. We have to look at land uses right next to the forested zone."

Rodewald and Yahner studied 10 forests central Pennsylvania, all about the same size. Five had farm patches in them while the remaining five had clearings left by timber harvesting.

The researchers surveyed bird populations inside the forests during the breeding seasons between 1997 and 1999, identifying individual nests and observing the activity of birds inside them.

"The first time we looked into a nest, we would make notes about the number of eggs inside," Rodewald said. "In subsequent observations, we would either find that the eggs had hatched successfully and the chicks were developing feathers - getting ready to fly out - or that the nestlings were gone and the nest had been destroyed. In the second case, we knew that the nest had most likely been visited by a predator."

After accounting for the differences in the amount of disturbance within each forest, Rodewald and her colleague found that nesting success in forested landscapes disturbed by farming was about two and a half times lower than in those disturbed by timber harvesting.

Rodewald said the most likely reason for the adverse impact of agriculture on nesting success was that the farm patches were somehow helping nest predators to thrive.

"Maybe the predators are getting supplemental food from these agricultural openings," Rodewald said. "Maybe it just helps them survive the winter, so you end up with higher populations of predators each year."

Compost Center Emissions Targeted for Cleanup

"Composting benefits the environment by recycling and reducing solid waste," said Barry Wallerstein, executive officer of the South Coast Air Quality Management District (AQMD). "However, the region's composting industry lacks air pollution controls and is a significant source of smog forming volatile organic compounds.

"Each industry must do its part to help us achieve clean air," Wallerstein added. "We have identified several effective and technically feasible pollution controls that could significantly reduce emissions from composting facilities."

AQMD presented a technology assessment of pollution controls for the compost industry to its Governing Board on Friday. The Board is scheduled to adopt the measure by this fall.

The rule would affect about 75 industrial composting and related facilities in the region, including:

• facilities that compost wood, leaves and grass, known as green waste
• co-composting facilities that combine green waste with sewage sludge, livestock manure or food waste
• chipping and grinding operations that process green waste for use as a landfill cover, biomass fuel or mulch

The AQMD is proposing to require dust controls and emissions filters for new composting facilities, and may require similar measures for existing facilities in the future. About 200 facilities would be exempt from the proposed rule, including community composting sites and plant nurseries.

Together, the region's composting facilities emit a total of 6.8 tons per day of volatile organic compounds (VOCs) and 4.7 tons per day of ammonia, according to studies conducted by the AQMD and other agencies. In comparison, the region's oil refineries emit a total of about nine tons per day of VOCs.

VOCs and ammonia are produced during composting when organic materials decompose. VOCs combine in the atmosphere with nitrogen oxides from combustion sources to form ozone. Ozone damages deep lung tissue and may be linked to long-term health effects.

Ammonia combines with oxides of nitrogen and sulfur oxides to form nitrate and sulfate particles, a component of particulate pollution. Particulate pollution degrades visibility and has been linked to increased hospital admissions and even premature deaths.

Supercritical Carbon Dioxide Could Clean Hazardous Wastes

A research team at the U.S. Department of Energy's Los Alamos National Laboratory is developing an environmentally friendly method for using supercritical carbon dioxide (CO2) and water to clean up contamination. In early tests, the technique removed almost all of the contaminants from materials exposed to the mixture.

The researchers believe the technique could be used to extract contaminants from containers and other types of waste generated by workers in laboratories and industrial plants. That would reduce the amount of wastes headed for hazardous waste landfills.

The Los Alamos team worked with a mixture of supercritical carbon dioxide and water, modified with the addition of a polyether. Their results were presented today at the 2002 meeting of the American Chemical Society.

By itself, supercritical CO2, which is CO2 under pressure and at a certain temperature, dissolves a number of materials, but now metal ions, said Los Alamos research team leader Mark McCleskey. But the only known way to use CO2 to extract metal ions was by combining it with a special kind of molecule known to combine with certain kinds of metals, a method with limited applications.

The Los Alamos team combined supercritical CO2 with an inert polyether that stabilizes water. They used the mixture, known as a microemulsion, to extract copper and europium from filter paper, wood, cement and activated carbon, recovering about 98 percent of the contaminants.

"We found that the metals targeted for extraction concentrated in the nanodroplets of water in the microemulsion, allowing us to separate the metals from the contaminated materials easily," McCleskey said. "In addition, the properties of this microemulsion allow penetration even into small pores of contaminated materials usually not accessible to bulk water."

Microemulsions are useful for extracting metals from waste, he explained, because the amount of water required is proportional to the amount of contaminant being removed, not to the amount of waste to be cleaned.

"The result is that grams of contaminants can be captured with just a few milliliters of water," McCleskey said.

Ultrasound Scrubs Water Filters

"If water treatment plants could clean water with membrane filters, they could minimize the cost, safety and disposal issues associated with the use of harsh chemicals," said Harold Walker, assistant professor of civil and environmental engineering and geodetic science at Ohio State.

Walker and colleague Linda Weavers, also an assistant professor, described their ultrasonic cleaning technique April 10 in a poster at the annual American Chemical Society meeting.

As an alternative to chemicals, researchers are studying ceramic membrane filters - honeycomb like networks of tiny channels separated by thin ceramic films or membranes. When water flows through the channels, the membranes act as sieves to catch contaminants such as clay, iron oxide, bacteria and viruses.

Over time, the membranes become clogged with contaminants and must be cleaned.

Based on recent research showing that sound waves can form and collapse bubbles inside a liquid, releasing heat and energy, Weavers and Walker decided to test whether collapsing bubbles could clean a ceramic filter. The engineers submerged a filter in water containing latex and silica particles to mimic the contaminants found in water treatment.

They used an ultrasonic probe to vibrate the water at 20 kilohertz, or 20,000 vibrations per second - a low frequency obtainable with typical ultrasound equipment. The 20 kilohertz vibrations caused bubbles for form and collapse, and kept the ceramic filter clean.

"The bubbles seemed to scour the surface of the filter," Weavers said. "Where the bubbles collapsed, tiny water jets formed and flushed away the contaminants."

Though the engineers are still not certain exactly how the process works, Weavers suspects that the jets sprang from vibrational nodes - locations along the surface of the filter where ultrasonic waves merge together and magnify each other.

With ultrasound as a cleaning method, water treatment plants would not have to remove filters to clean them, Walker said. Loosened contaminants would wash away in an exhaust flow separate from the clean water.

"If you left the ultrasound running, you could clean a filter while it was still in use, and keep it from ever getting clogged in the first place," Weavers added.

Industry: U.S. Could Tap Vast Geothermal Energy Sources

Geothermal energy production has expanded 50 percent over the past decade and is now serving over 47 million people worldwide, the GEA said today. At the beginning of the century, 21 countries produced electricity using their geothermal resources, or heat from the earth.

But geothermal production in the U.S. and Europe has shown just a slight increase, while other countries have had much larger gains. Over the last decade, geothermal production in Indonesia quadrupled, Japan almost tripled its geothermal power, and production from geothermal sources doubled in the Philippines, now meeting 25 percent of the country's total electricity needs.

In contrast, there has been almost no growth in total U.S. geothermal energy production in the past decade.

"But this could change," said Karl Gawell, executive director of GEA. Measures being considered in Congress could bring on a new geothermal power boom in the U.S., he explained.

"If Congress acts to support renewable energy, we could see a return to the double digit annual growth that occurred in the '80s," Gawell said.

The GEA highlighted two Senate energy bill provisions: the production tax credit and renewable portfolio standard.

The Senate bill would expand the production tax credit to new geothermal facilities. This tax provision is credited with fueling the growth of the wind industry in the U.S., but is not now available to other renewable technologies. The Senate has also adopted a national renewable portfolio standard that would require power generators to produce 10 percent of their electricity from renewable resources by 2020.

"The progress made over the past decade is good news for the earth's environment, but just the beginning of what we could do if governments placed greater emphasis on developing their geothermal and other renewable energy resources, particularly the U.S. government," Gawell said.

The GEA says that geothermal resources have the potential to support 80,000 megawatts of power using today's technology, which would meet the electricity needs of 865 million people.

"The heat of the earth is an enormous resource that we have just begun to tap," said Gawell.