1 / 9

Biogeochemical Cycling – Fall 2010

Biogeochemical Cycling – Fall 2010. Theme Modern Changes in the Nitrogen Cycle. Friday Discussion Group Discussion Leader: Priya Ganguli 12 November, 2010. N 5 th most abundant element in solar system Essential for synthesis of nucleic acids and proteins

jason
Download Presentation

Biogeochemical Cycling – Fall 2010

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Biogeochemical Cycling – Fall 2010 Theme Modern Changes in the Nitrogen Cycle Friday Discussion Group Discussion Leader: Priya Ganguli 12 November, 2010

  2. N 5th most abundant element in solar system • Essential for synthesis of nucleic acids and proteins • For every 100 atoms of C in cells, need 2 to 20 atoms of N • Biogeochemistry of N primarily oxidation-reduction and microbially mediated • Secondarily influenced by long-term cycling through geosphere • N2 largely unavailable to organisms • NO3- and HN4+ (fixed forms) often limit primary productivity in both marine & terrestrial ecosystems

  3. Nitrogen Fixation prokaryotes in bacterial and archaeal domains reduce N2 gas to ammonium ion (NH4+)

  4. nitrate (NO3-) reduction coupled to anaerobic oxidation of Corg • N2 gas • (denitrification) • or • NH4+ • (dissimilatory nitrate reduction to ammonium) (DNRA) electron acceptors from Baker MA, Dahm CN, Valett HM, 2000

More Related