Surprisingly, leaves damaged mechanically by a pattern wheel and having the same extent of herbivore damage had lower emissions of both major and minor compounds in comparison to control plants, particularly in comparison to herbivore wounded leaves (Figs. 2a and 2b).
A plug-in hybrid can lower emissions of carbon dioxide and smog-causing gases.
The EPA's more stringent standards include lower emissions of nitrogen oxides, sulphur dioxide, soot and mercury.
Such increased use of gas also reduces emissions of other pollutants; compared with burning coal, combustion of natural gas results in lower emissions of sulphur dioxide (SO2), nitrogen oxides (NOX) and gas also emits almost no particulate matter.
Compared with conventional gasoline cars, they offer lower emissions of the kind that contribute to global warming but lag behind in emissions of smog-forming pollutants -- though filtration technology is improving.
A bill intended to lower emissions of greenhouse gases, introduced last week by Senator Joseph I. Lieberman, independent of Connecticut, and Senator John W. Warner, Republican of Virginia, sets goals that would be virtually impossible to achieve without new nuclear plants.
Ultimately, we must do more with less – produce more food on the same amount of land, with less water, fertilisers and pesticides, as well as achieve lower emissions of greenhouse gases.
Only companies with that kind of scale, Mr. Marchionne argues, will be able to bear the expense of developing new technologies, especially as governments demand higher fuel efficiency and lower emissions of the gases that contribute to global warming.
With his address, Mr. Bush essentially provided his answer to an international treaty intended to lower emissions of carbon dioxide and other heat-trapping gases that his administration rejected in March.
It says that poorer nations have a "right to economic development" and that their wealthier counterparts ought to help them develop technologies that would produce lower emissions of heat-trapping gases.
