Earth on Fire: The Overheating Planet

Earth on Fire: The Overheating Planet

Google+ Badge

Follow EStar by email

NOTE ON POPULAR POSTS

The reason some popular posts are tagged ‘no title’ is not because they have no title—they all do—but because the old Blogger embedded the title at the top of text, and the new software does not see that. You can see the titles in capitals at the start of each snippet. (It would be nice if Blogger introduced an upgrade program that could fix this little problem.)

Popular Posts

Thursday, 21 October 2010

HUMAN EFFECT ON NITROGEN RISKS GLOBAL DAMAGE

An authoritative study published in the October 8 issue of Science magazine (the publication of the American Association for the Advancement of Science) sounds the alarm over what humans are doing to the Earth's nitrogen cycle.

Micro-organisms have been controlling the cycle since life began on the planet. With life evolving around it, nitrogen became both an essential nutrient and a major regulator of climate.

The study in Science (pages 192-196, Vol 330, Oct 8 2010) reviews the major changes there have been to the nitrogen cycle throughout the Earth's history. Most of the time they coincided with the arrival of new organisms that provided new metabolic pathways.

But the last century has seen humans push the biological nitrogen cycle into a very different stage. Adding large amounts of fixed nitrogen in the form of fertiliser chokes out aquatic life that relies on run-off, and significantly increases the amount of NO2 in the atmosphere ( a greenhouse gas 300 times more potent than CO2).

Micro-organisms may one day restore balance in the nitrogen cycle that they helped shape for billions of years, but humans must change their behaviour, or risk causing irreversible changes to life on Earth.