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For more information on these science news and feature story tips, please contact the public information officer at the end of each item at (703) 292-8070. Editor: Bill Noxon Contents of this News Tip:
SCIENTISTS DEMONSTRATE NEW NEED TO PRESERVE BIODIVERSITYEcologist Peter Morin and Rutgers University colleagues have found an important new role for biodiversity: linking diversity of species to ecosystem predictability. Funded by the National Science Foundation (NSF), Morin, graduate student Jill McGrady-Steed and postdoctoral fellow Patricia Harris discovered that the predictability of ecosystems is linked to their biodiversity. A paper detailing results of their research is published in the November 13 issue of Nature. Using a community of microbes to act as a model system, the team examined whether loss of species caused a decline in ecosystem function. By simulating species loss from an initially diverse community, researchers were able to find out how loss of biodiversity influenced various ecosystem functions, including resistance to invasion and decomposition of organic material. "The experiments have shown that species richness can buffer an ecosystem against the effects of external factors," says Morin. Adds McGrady-Steed, "Ecologists have long been concerned about the potential consequences of reduced biological diversity in natural systems. Our research shows that various 'ecosystem services' decline as biodiversity declines." The study's findings suggest that in ecosystems with moderate loss of species, remaining species can compensate for those that have been lost. But there is a limit to this compensation: ecosystems with an excessive loss of biodiversity show definite reduced functioning. [Cheryl Dybas] R&D SPENDING EXCEEDS EXPECTATIONSU.S. research and development (R&D) expenditures in 1995-97 grew faster than the U.S. economy as a whole, reflecting steep increases in industry spending, according to a new NSF Data Brief. Total 1997 R&D spending in the U.S. will reach $205.7 billion according to current projections reported in the NSF brief. The projection represents a 6.5 percent increase over the $193.2 billion spent in 1996 (before adjustment for inflation). The 1996 figure is a 5.6 percent increase in R&D over 1995, which was 8.6 percent higher than 1994. Adjusting for inflation, U.S. R&D increased by 3.8 percent in 1997, 3.2 percent in 1996, and 5.9 percent in 1995. Industry has provided the greatest share of total support for R&D since 1980, with $133.3 billion projected for all of 1997 -- a 7.3 percent increase in real terms over 1996. Of these funds, nearly all ($130.6 billion) will be devoted to R&D performed by industry itself, with the remaining $1.7 billion invested in academic R&D and $1.0 billion going to R&D performed by nonprofit organizations. In contrast, federal R&D support in 1997 ($62.7 billion) is expected to decline 2.7 percent in real terms from 1996. Since 1990 the federal share of national R&D spending has dropped steadily, rendering for 1997 the lowest share (30.5 percent) reported in NSF's 45-year-old R&D data series. See the data brief at the NSF-Science Resources Studies division web page: http://www.nsf.gov/sbe/srs/stats.htm [George Chartier] CARBON, NOT SULFATE, PREVAILS IN POLLUTED D.C. AIRIn the first direct measurements of aerosols over the highly polluted U.S. Eastern Seaboard, scientist Peter Hobbs of the University of Washington and his colleagues have found that carbon particles outnumber sulfates. Hobbs' research was through the NSF-supported National Center for Atmospheric Research in Boulder, Colorado. Carbon aerosol particles are thought to increase global warming by absorbing solar radiation, while sulfate particles are thought to have a cooling effect by reflecting incoming sunlight back into space before it reaches the lower atmosphere. Aerosols include dust, other particles, and very small droplets; their sources are natural, human, or both. In recent years, researchers have become more aware of these aerosols' effects on climate, but many uncertainties remain about what, where and how strong are the effects. Using research aircraft, Hobbs took measurements of the size and optical properties of aerosol particles in polluted air extending over the Atlantic Ocean east of a 200-mile urban corridor centered in Washington, D.C. The carbon he found in the atmosphere was partly elemental carbon (soot) from the burning of forests and the inefficient use of fossil fuels. He also found organic carbon, some from industrial emissions and some from natural sources such as ocean gases. "The findings came as a surprise," says Hobbs. To find out whether these results are specific to the research area or more universal, he said further "measurements are needed in other urban airsheds." [Cheryl Dybas]
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