мелкие козявки
May. 23rd, 2011 12:00 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png)
Agriculture alone contributes about 2.4x10^12 mol N /year because of cultivation-induced nitrogen fixation. Fossil fuel combustion generates another 1.8x10^12 mol/yr. Together, anthropogenic sources contribute double the natural rate of terrestrial nitrogen fixation, and they provide around 45% of the total fixed nitrogen produced annually on Earth.
http://www.sciencemag.org/content/330/6001/192.short
http://www.sciencemag.org/content/330/6001/192.short
no subject
Date: 2011-05-24 07:23 am (UTC)