Leaves Reveal Fossil Fuel Emissions
By chemically analyzing corn leaves, scientists in the US were able to deduce how much carbon dioxide from fossil fuels was in the air. This might be a simple and inexpensive way to track how and where such emissions are distributed in the atmosphere.
Researchers led by James Randerson at the University of California at Irvine chose corn because it is grown in many areas and, as an annual, provides a clear retrospective view of only that year of growth. They dried the leaves and converted them into graphite, which they analyzed in a mass spectrometer for radiocarbon content (14C). Since fossil fuels no longer contain measurable concentrations of 14C, the scientists were able to see how much of the carbon stored in plant tissue through photosynthesis came from corresponding emissions and use this to calculate their share of the carbon dioxide content in the air.
Their method should help to better understand emission patterns and changes in the atmosphere and thus better regulate fossil combustion processes, says Susan Trumbore from the research team. You can use it to directly measure the emission of carbon dioxide, which contributes to global warming. (af)