From soil to atmosphere more than expected
2005/09/01 Elhuyar Zientzia Iturria: Elhuyar aldizkaria
Nitrogen oxides from fires and burning fossil fuels are highly polluting. They are one of the agents of ozone near the earth. This ozone is harmful to health and plants.
They have now analyzed the origin of nitrogen oxides at the University of Washington, USA, based on data collected by the ESA satellite, Remote Sensing 2. Researchers have been surprised to see that 22% of the nitrogen oxides in the atmosphere occur in the soil. 64% is generated in the use of fossil fuels and the remaining 14% in fires. That is, much more is generated than expected in the soil.
Precisely when the rainy season begins in equatorial Africa and in the middle latitudes of the Northern Hemisphere it is at the beginning of summer when the greatest release of nitrogen oxides occurs. It seems that moisture and sweet temperatures stimulate soil bacteria. As a result, nitrogen begins to be processed and the gas released by this activity is detectable by satellites.
The territories that most release nitrogen oxides are the African area of the Sahel, the central US, the plains of northern Asia, much of India and southwest Europe. Except for saheles, agriculture is responsible for the production of so many nitrogen oxides. The presence of bacteria in the fields is abundant in the soil, aggravated by the use of fertilizers.
